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Suggested Citation:"Mexico." National Research Council. 1993. Sustainable Agriculture and the Environment in the Humid Tropics. Washington, DC: The National Academies Press. doi: 10.17226/1985.
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Mexico

Arturo Gómez-Pompa, Andrea Kaus, Juan Jiménez-Osornio, David Bainbridge, and Veronique M. Rorive

In tropical Mexico and throughout the nation, deforestation is not only an ecologic concern but also an indicator of much wider social, political, and economic factors. It is the result of ecologic conditions combined with land use patterns as well as human decisions and the consequent actions on the tropical environment. These decisions are influenced by internal and external social and environmental factors, from local land tenure to national politics and from local soil conditions to widespread natural disasters. This profile briefly reviews the social and economic contexts in which deforestation occurs and discusses land use patterns, forest resources and rates of deforestation, and sustainable resource management.

Arturo Gómez-Pompa is a professor of botany and plant sciences at the University of California, Riverside, California, and is director of the University of California Institute of Mexico and United States; Andrea Kaus is codirector of Groundworks International, Inc., Riverside, California; Juan Jiménez-Osornio is a professor of ecology and coordinator of the Tropical Natural Resources Management and Conservation Program at the Autonomous University of Yucatán, México; David Bainbridge is restoration ecologist in the Biology Department at San Diego State University, San Diego, California; and Veronique M. Rorive is research assistant to Arturo Gómez-Pompa at the University of California, Riverside, and codirector of Groundworks International, Inc., Riverside, California.

Suggested Citation:"Mexico." National Research Council. 1993. Sustainable Agriculture and the Environment in the Humid Tropics. Washington, DC: The National Academies Press. doi: 10.17226/1985.
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THE SOCIAL AND ECONOMIC CONTEXT
Past Population and Land Use in the Mexican Tropics

Demographic change in Mexico from the time of contact with Europeans to the present has been a subject of study and debate by many scientists and scholars. Cook and Borah (1980) estimated that the native Indian population of Central Mexico in 1518 was 25.1 million people. Yet, by 1620 only 750,000 people remained. Diseases and war had reduced the population to a fraction of its former size.

The depopulation of Mexico after conquest by the Europeans was followed by the introduction of large-scale agricultural activities in the tropical forests. Cattle ranching, in particular, has become a major factor in the economy and ecology of present-day Mexico. The replacement of traditional tropical land use practices with techniques and agricultural models imported from temperate zones and Western European experience has led to cultural degradation along with the loss of biologic and genetic diversity.

The food production systems found in pre-Hispanic times were more efficient than the systems found there today. In pre-Hispanic times, intensification of agricultural production was well developed. According to Gliessman et al. (1983), Gómez-Pompa (1987a), Siemens (1983), and Turner (1974), the principal subsistence systems known to have existed were shifting agriculture (probably very intensive with short rotations and carefully managed fallows), tree orchards (including cacao with leguminous trees), different types of extensive and diverse forest gardens, terraces, and intensive hydraulic agriculture in lowlands and swamps.

The most notable examples of intensive hydraulic systems in the archaeological record are the raised fields of the Maya lowlands. These are thought to have provided a highly sophisticated agricultural system based on intensive human labor combined with the efficient use of water and renewable biological resources (Denevan, 1970; Gliessman et al., 1983; Gómez-Pompa and Jiménez-Osornio, 1989; Siemens and Puleston, 1972). The ancient Maya also hunted and gathered in the noncultivated areas and may have managed the mature vegetation to improve the level of production from forest resources.

Despite discrepancies and gaps in the available data, it is increasingly evident that present-day rural lands once contained urban centers and human populations larger than those supported today by modern land use practices. Furthermore, areas now considered to be “virgin ” forest or “pristine” ecosystems were previously inhabited

Suggested Citation:"Mexico." National Research Council. 1993. Sustainable Agriculture and the Environment in the Humid Tropics. Washington, DC: The National Academies Press. doi: 10.17226/1985.
×

and, in many cases, still support indigenous populations and their traditional forms of agriculture (Gómez-Pompa and Kaus, 1992).

At present, Mexico has millions of farmers who belong to more than 50 ethnic groups, each with their own language, traditions and land use practices. Loss of the cultural diversity once found in the tropical forests means a loss of the opportunity to understand and learn from the experiences of others who live and work in tropical regions (Bennett, 1975). The value of traditional land use practices for agricultural development and conservation efforts under current socioeconomic conditions is often underestimated because of two principal myths: (1) the myth that the campesino (peasant) or Indian is ignorant of “modern” problems (Redford, 1990; Wilken, 1987); and (2) the myth that shifting cultivation is the sole cause of deforestation (Repetto, 1990).

Tropical deforestation occurs as a result of Western, indigenous, and mestizo land use practices. However, much can be learned from the failures as well as the successes. Traditional land use practices, that is, the techniques developed over generations in a given region, provide examples of time-tested experiments of human ingenuity in linking the natural and social environments. The added benefit is that these practices are not rigidly fixed and can adjust to and even alter environmental trends based on farmers' predictions and evaluations of future change.

Present Socioeconomic Trends in Mexico

In Mexico there are several nonecologically based trends that both contribute to tropical deforestation and indicate the need to create incentives that will alter the present predominance of unsustainable land use policies and practices. This situation is not only critical for reasons of environmental degradation but also for the well-being of Mexico's citizens.

At present there is a low density of inhabitants in the tropical regions of Mexico in comparison with estimations of the densities during the pre-Hispanic era. According to the latest census by the Instituto Nacional de Estadística Geografía e Informática (INEGI), the population of Mexico was 81,140,922 in 1990 (National Institute of Statistics, Geography and Information, 1990a). The World Bank (1990), however, estimated that Mexico had a population of 87,262,000 in 1990. The estimates of the World Bank were based on 1980 census figures; and the newest INEGI census produced figures that cannot be explained, for example, a decrease in the population of the Federal

Suggested Citation:"Mexico." National Research Council. 1993. Sustainable Agriculture and the Environment in the Humid Tropics. Washington, DC: The National Academies Press. doi: 10.17226/1985.
×

FIGURE 1 The urban and rural populations of Mexico, from 1940 to 2000, as estimated.

District from 8,831,079 to 8,236,960 inhabitants, which is highly unlikely.

According to INEGI (1990a), the population of Mexico increased sixfold during the twentieth century, from 13,607,272 to 81,140,922 inhabitants, and continued increases are projected in the future (Figure 1 ). These population increases will likely add to the already increasing population density in tropical regions of Mexico.

According to Cabrera (1988), the debate on population growth dates back to the early 1960s. In 1963, the Bank of Mexico produced the first long-term projections of population growth and the potential impact on various economic areas, particularly the agricultural sector. In the early 1970s the Mexican government reacted by proposing the General Law on Population, which was approved in 1973. The law stated the need to regulate population growth to obtain a just and equitable distribution of the benefits of economic and social development. This was the beginning of the family planning programs of the Mexican government, whose goals in 1977 were to diminish population growth to 1 percent annually by the end of the century. The programs were well received. By 1988, annual population growth had been reduced to 2 percent. The goal of 1 percent annual population growth by the year 2000 appears to be feasible.

More than one-third of the present population of Mexico, however, is less than 15 years old, and the labor force (those 15 to 64

Suggested Citation:"Mexico." National Research Council. 1993. Sustainable Agriculture and the Environment in the Humid Tropics. Washington, DC: The National Academies Press. doi: 10.17226/1985.
×

years of age) continues to grow at a rate of 3.5 percent per year (Ministry of Finance and Public Credit, 1991) requiring at least 800,000 new jobs each year. Since neither opportunities nor jobs are being provided by the agricultural sector in rural areas, many workers migrate to the major urban centers. The industrial sector has been unable to employ this growing work force. In 1988 unemployment reached a level of 24.5 percent (6.5 million people were unemployed and 20.1 million people were employed) (Calva, 1988).

Forty-five percent of the agricultural population of southeastern Mexico can be classified as infrasubsistence farmers, that is, those who do not produce enough food to sustain their own households. An inadequate food supply in Mexico is not a matter of inadequate food production. It is related to unequal income distributions and flawed food distribution policies. Mexico has initiated many efforts to address the constant problems of unequal food distribution and poor living conditions in rural areas. Yet, they have not solved the underlying discrepancies in income and wealth distribution.

One of the key components for a sustainable land use strategy in a peasant economy is food self-sufficiency, allowing, at the very least, for a family to sustain itself on the same plot of land over time (Calva, 1988; Comisión Económica para la America Latina, 1982, Cordera and Tello, 1981; Toledo et al., 1985). In the early 1980s, the Mexican government initiated SAM (Sistema Alimentario Mexicano [Mexican Nutrition System]), a program for food self-sufficiency. The main objective of SAM was to make Mexico self-sufficient in basic grain production within 2 years. This was possible, given that funds were available for credit, fertilizers were provided, no constraints were placed on the use of livestock pastures for growing crops, and the producers were able to make a good profit. The program was so successful in terms of production that the country was not prepared for the surplus. Thousands of metric tons of maize spoiled because of a lack of storage capacity in Veracruz or were used as fodder for cattle. In 1982, however, a combination of late rains and the devaluation of the Mexican peso reduced the grain yield and the ability of the government to invest heavily in the program. The program was terminated with the change in Mexican presidents in the same year (Riding, 1989).

Results of the SAM program show that distribution, storage, and access to land suitable for crop production are more important for low-income families than is increased production for improving the lives of people in Mexico. The experience of SAM also shows the potential capacity of agricultural lands and Mexican farmers to produce food surpluses if farmers are given sufficient means and incentives. The failure of the SAM program shows the dependence of

Suggested Citation:"Mexico." National Research Council. 1993. Sustainable Agriculture and the Environment in the Humid Tropics. Washington, DC: The National Academies Press. doi: 10.17226/1985.
×

adequate land use strategies on the social, economic, and political factors that exist external to the region of production.

Food production for external markets is different from production of basic commodities for use by farm households, and they must be examined from different perspectives. In much of Mexico, local peasant farmers do not concentrate on producing basic items like maize and beans, but produce specialty items like fruits and vegetables for a market that demands a wide range of products. The present infrastructure in Mexico cannot deal with the development of small-scale production of various specialty items because of transportation, storage, processing, marketing, and credit limitations, although small-scale production is an integral part of the peasant economy and a starting point for building equity into agricultural systems.

There was some concern in the past that Mexico's need to be self-sufficient in food production would take away from its ability to export agricultural products. However, these two forms of land use and priorities represent two types of production that commonly use different types of land. They need not be mutually exclusive. In Mexico's agricultural boom of the early 1960s, 1,549,577 ha (13.7 percent of the cultivated land at that time) was used to grow crops for export. By 1979, this amount had dropped to 1,224,697 ha, at the same time that Mexico lost its self-sufficiency in food production. In fact, over the past 2 decades, Mexico has increasingly relied on food imports rather than internal production. From 1966 to 1987, average maize imports increased 17-fold (from an average of 157,103 metric tons between 1966 and 1970 to 2,821,860 metric tons between 1983 and 1987). Wheat imports, on the other hand, increased nearly 300-fold (from an average of 1,157 metric tons between 1966 and 1970 to 345,501 metric tons between 1983 and 1987) (Calva, 1988).

A new trend in Mexico is to advocate food self-reliance. The objective is to produce 75 to 80 percent of the basic grains (maize, rice, and wheat) within Mexico (Calva, 1988). Mexico has the agricultural capacity for increased internal production without losing export potential (a considerable amount of land now used for livestock grazing could also be used to grow crops for export) (Table 1). However, little new agricultural land is available for extensive production. A 1987 evaluation by the Secretary of Agriculture and Hydraulic Resources of Mexico shows that Mexico has an agricultural reserve of 9.5 million ha and a total of 32.7 million ha with agricultural potential (Calva, 1988). Half of the 9.5 million ha is forested; the other half is used for cattle grazing. More than half (5.2 million ha) of this total is in the humid tropics and would require drainage and irrigation for agricultural use.

Suggested Citation:"Mexico." National Research Council. 1993. Sustainable Agriculture and the Environment in the Humid Tropics. Washington, DC: The National Academies Press. doi: 10.17226/1985.
×

TABLE 1 Area Planted for Consumption and Export Crops, 1960–1979

 

Area (in hectares)

Year

Human Consumption

Export

Forage

1960

9,163,406

1,549,577

320,266

1965

12,033,043

1,458,733

567,265

1971

12,270,642

1,174,372

1,325,813

1979

9,919,403

1,224,697

2,508,991

SOURCE: Calva, J. L., ed. 1988. Crisis Agrícola y Alimentaria en México: 1982–1988. México, D.F.: Fontamara 54.

The potential for improved production still exists for land that is already in agricultural use. Food self-reliance can be obtained by increasing the level of production per ha without using any more land. Maize production alone could be increased from 1.6 to 3.2 metric tons/ha by using already available technologies. These higher yields do not necessarily require increases in purchased or nonrenewable inputs, as the high production from some traditional farming systems shows (Wilken, 1987). Often, better knowledge is the only thing required to obtain better yields. A. Turrent and associates from the National Institute of Forestry, Agriculture and Animal Husbandry Research (INIFAP) have shown increased productivity from local farmers' fields through the use of simple technologies and techniques such as alley cropping, terracing, intercropping, and in situ postharvest seed conservation.

Past efforts for improved production in Mexico have not considered the various production components of Mexican small farms. Labor-intensive practices such as terrace construction, intercropping, soil improvement by nonchemical means, pest management, or simple irrigation techniques that rely on hand-carried water are often over-looked (for a full discussion of these methods, see Wilken, 1987). The female sector of the work force is typically forgotten or undervalued, even though the household economy often depends on their contribution to child care, gardening, small livestock production, firewood collection, food processing and preparation, and carrying water. Also overlooked is the value of the work done by children and elderly members of the household, whose contributions through experience or basic labor can be important for the family. However, the lack of recognition of traditional farming techniques, the contributions of various household members, or even self-sufficiency is not the only

Suggested Citation:"Mexico." National Research Council. 1993. Sustainable Agriculture and the Environment in the Humid Tropics. Washington, DC: The National Academies Press. doi: 10.17226/1985.
×

TABLE 2 Contribution of Natural Renewable Resources to the Gross National Product (GNP), 1987

Sector

Valuea

Percentage of GNP

Agriculture

242,419

5.06

Animal husbandry

132,945

2.77

Silviculture

20,616

0.43

Hunting and fishing

15,460

0.32

Wood industry

37,953

0.79

Paper products and printing industry

61,303

1.28

a Millions of 1980 pesos.

SOURCE: Department of Agriculture and Hydraulic Resources. 1987.Inventario Cartográfico de Recursos Agropecuarios y Forestales yClasificación Agrológica Estatal Sobre Frontera Agrícola y Capacidad de Uso del Suelo. Mexico, D.F.: Secretaryof Agriculture and Hydraulic Resources.

gap in present and past efforts to alleviate problems of low levels of agricultural production and poverty in the Mexican tropics. None of the programs will improve without the participation of farmers in the decisions that affect their work and living conditions or without their direct control of production (Chambers et al., 1989).

The agricultural sector remains an important contributor to the Mexican economy, but it is underdeveloped (Table 2). Forestry has played a very minor role in the economy, but it could contribute more if it were developed to its full potential and properly managed for its long-term production capability. In 1989, forestry 's contribution was only 1.9 percent of the gross national product (GNP). Wood production has been maintained at a level of 9 million m3/year, which is only 23 percent of the potential level of production by a recent estimate (Comisión Nacional Forestal, 1988). At the same time, Mexico has imported an average of US$228 million of wood products per year over the past 10 years (Comisión Nacional Forestal, 1988).

Land Use

The present socioeconomic trends in the agricultural sector of Mexico coupled with increasing environmental degradation indicate the urgent need for alternatives in resource management. These alternatives should provide for the basic needs of peasant households

Suggested Citation:"Mexico." National Research Council. 1993. Sustainable Agriculture and the Environment in the Humid Tropics. Washington, DC: The National Academies Press. doi: 10.17226/1985.
×

without depleting the natural resources on which both the households and the national economy rely. The resource management options available in the Mexican humid tropics are similar to those available in other tropical regions of the world and are dependent on the land area that is to be managed, the available capital and infrastructure, and knowledge of the available technologies and potential markets.

In tropical Mexico, as in other tropical countries, two types of agricultural producers can be found on either end of a gradient ( Table 3): (1) a large group of infrasubsistence farmers who practice traditional agriculture on small parcels of land, mainly for their own subsistence, and (2) a much smaller group of farmers who run large businesses that produce goods for regional, national, and international markets. CEPAL (1982) refers to these producers as peasant agriculture and commercial agriculture, respectively. Farmers who practice agricultural methods between these two extremes are called transitional farmers.

Peasant agriculture is practiced by 88 percent of the farmers on 57 percent of the country's agricultural lands. It relies primarily on household labor. Within the peasant agricultural sector, infrasubsistence farmers make up 45 percent of the agricultural producers in tropical Mexico. On average, their parcels are less than 4 ha. In contrast, commercial producers represent only 2 percent of the agricultural sector in the southeastern states of Mexico and hold 21 percent of the agricultural lands in that region, with average parcel sizes of more

TABLE 3 Types of Agricultural Producers (in Percent)

Producer Type

Number of Producers

Agricultural Area

Work Days in the Field (per year)

Infrasubsistence

55.7

10.8

29.6

Subsistence

16.2

11.1

13.4

Stationary

6.5

7.4

6.1

Excedentaries

8.2

27.5

9.2

Transitional

11.6

22.4

28.4

Small business

1.1

7.2

5.7

Medium-sized business

0.4

5.0

2.6

Large business

0.3

8.6

5.0

Suggested Citation:"Mexico." National Research Council. 1993. Sustainable Agriculture and the Environment in the Humid Tropics. Washington, DC: The National Academies Press. doi: 10.17226/1985.
×

NOTE: “Number of producers” is not stated in whole numbers because many of these producers must be classified in more than one of these categories.

SOURCE: Comisión Económica de la America Latina. 1982. Economía Campesina y Agricultura Empresarial. México, D.F.: Siglo XXI Editores.

TABLE 4 Types of Agricultural Producers, by State (in Percent)

State

Infra-subsistence

Subsistence

Stationary

Surplus

Transitional

Small Business

Medium-Sized Business

Large Business

Campeche

59.0

22.9

4.6

6.0

6.2

0.7

0.3

0.3

Quintana Roo

90.4

2.4

0.4

0.3

6.1

0.3

0.1

Tabasco

25.3

21.6

14.8

27.9

8.4

1.2

0.5

0.3

Veracruz

39.2

16.1

9.5

13.0

19.9

1.5

0.5

0.3

Yucatán

82.4

7.2

1.8

1.5

5.8

0.5

0.3

0.5

SOURCE: Comisión Económica de la América Latina. 1982. Economía Campesina y Agricultura Empresarial. México, D.F.: Siglo XXI Editores.

Suggested Citation:"Mexico." National Research Council. 1993. Sustainable Agriculture and the Environment in the Humid Tropics. Washington, DC: The National Academies Press. doi: 10.17226/1985.
×

than 12 ha (Table 4). They also have rights to 42 percent of the irrigated lands, whereas the peasant agricultural sector has rights to only 10.4 percent of the irrigated lands (Comisión Económica de la América Latina, 1982; Volke Haller and Sep úlveda González, 1987). Although the irrigated districts have attracted agriculturalists, there has also been a general trend of migration out of the region. One contributing factor is that the mechanization of agriculture associated with large-scale irrigated agriculture has replaced hand labor (Cabrera, 1979).

For the development of sustainable agricultural systems that integrate the concepts of agroecology with available information on alternative cropping systems, an agricultural model based on small-scale farmers who farm small parcels of land would have excellent potential. Small-scale producers already play an important role in export crop production in the Mexican humid tropics. For example, most coffee producers are not large-scale landholders, although coffee is a lucrative export crop (Nolasco, 1985). Sixty percent of the coffee plantations in Mexico are between 1 and 5 ha, and coffee plantations of this size account for 31 percent of the total area devoted to coffee plantations and 30 percent of total coffee production (Mexican Institute of Coffee, 1974).

Scherr (1985) noted that in the 1970s the average size of cacao farms in Tabasco was less than 3 ha. The parcel size is dependent on the availability of family labor and has likely averaged from 4 to 6 ha for centuries (Scherr, 1985). A frequent strategy of cacao and coffee growers is to have an interim phase of subsistence crop production while waiting for the cacao harvest. A sociodemographic survey of Tabasco showed that only 30 percent of the farmers planted cacao alone; the remainder planted maize, bananas, coconut or sugarcane, or included cattle production. Farmers with less than 2 ha of land were more likely to produce cacao alone or to grow only maize as a secondary crop (Scherr, 1985).

Improved production and self-sufficiency among small-scale landholders hold the potential for reducing destructive agricultural practices in tropical areas of Mexico. The agricultural practices of small-and large-scale landholders and long-term residents as well as recent immigrants contribute to the real and potential destruction of tropical forests. However, the greatest population concentration is found among small-scale landholders and recent colonists (immigrants who have claimed land they settled on). People in these two groups are often blamed for causing deforestation and for practicing unsustainable agricultural techniques. They also represent the people with the least means and support for improving their agricultural practices. Yet,

Suggested Citation:"Mexico." National Research Council. 1993. Sustainable Agriculture and the Environment in the Humid Tropics. Washington, DC: The National Academies Press. doi: 10.17226/1985.
×

they could be an underestimated ally in the use of sustainable agricultural systems and conservation practices in the humid tropics.

Small-scale farmers have much to gain from programs that enhance their self-sufficiency in food production and the security of their land tenure. In turn, long-term residents have much to contribute to current research on sustainable agriculture based on their intimate knowledge and experience with the land and on both their successes and failures with different techniques or crops. However, the means for sustainable agriculture are not attainable for the majority of these farmers. Credit, infrastructural support (for example, equipment, machinery, transportation), and adequate technology and information are usually not available; and those government credit, development, or agricultural programs that do exist often advocate unsustainable land use practices. Most small-scale farmers are more concerned about short-term production practices with the means available to them than about investing capital or labor in unpredictable and uncertain high-yield, technology-intensive practices. Sustainable agricultural systems need to be designed so that the small-scale farmers of Mexico can be included in the efforts to halt tropical deforestation. However, sustainability is not confined only to ecologic continuity; sustainable agricultural systems must also be economically viable and culturally acceptable if they are to be supported by the majority of the small-scale farmers. New initiatives must also take into consideration income and land distribution inequities along with insecure land tenures. Failure to take these factors into account led to the high social cost of the green revolution's technological package. Despite dramatic increases in food production, the green revolution provided greater benefits for the large-scale producers and landholders and provided few benefits for the small-scale farmers (Dahlberg, 1990; Perelman, 1976).

An emphasis on production, a belief in the neutrality of technology, and a poor accounting of the environmental and social costs have encouraged the replacement of ecologically complex farming systems with extensive monocultural systems. Plant breeding efforts that focus on grain have neglected a wide range of products that small-scale farmers need, such as thatch and fodder. Increases in crop yields generally require irrigation and high levels of fertilizer inputs (Stewart, 1988). The high-yielding crop varieties that respond well to high inputs of fertilizer and water are often less pest and drought resistant than traditional varieties, and their cultivation, combined with the overuse of chemical pesticides, leads to the emergence of new pests as a result of the elimination of natural predators (Perelman, 1976; Van den Bosch, 1980).

Suggested Citation:"Mexico." National Research Council. 1993. Sustainable Agriculture and the Environment in the Humid Tropics. Washington, DC: The National Academies Press. doi: 10.17226/1985.
×

The development of these extensive monocultural systems has also had profound effects on small-scale landholders and farm laborers, many of whom have been displaced by land consolidation and mechanization. For small-scale farmers, the new seeds and technological inputs are expensive. Farmers often apply for rural credit from banks or aid from government programs, increasing the risk of the agricultural venture for the household while transferring control to the bank or the government.

Control over land use by small-scale farmers is further complicated by the nature of land tenure in Mexico. At present, the principal forms of land tenure are federally owned land, private properties, ejidos, and comunidades. Comunidades are the least common, referring to villages whose usufruct rights (the legal right to use and enjoy the fruits or products belonging to somebody else) have been restored for land used before the Mexican Revolution (1910–1920). Ejidos are the most common form of land tenure and refer to lands where the usufruct rights have been given to a collective of Mexican citizens as part of the land reform established after the Mexican Revolution (Sanderson, 1984; Yates, 1981). The land itself, however, remains the property of the Mexican government. Private properties with land areas that exceed the amount established by the Mexican Constitution are also at risk of expropriation by the government, usually for redistribution to landless peasants as ejidos. Ejidos may be worked individually or collectively, but the responsibility for the ejido, in terms of management and administration, is collective. The stability of the entire ejido system has been thrown into doubt with the remarkable and unanticipated government regulatory changes of 1991 that allow the sale of ejido land and use of ejido land as collateral for loans. The full implications of these changes will not be apparent for some time but the goal has been to increase efficiency in agricultural production.

The ejidatarios (the beneficiaries of ejidal grants) must maintain the productive use of their land in order to retain their right to use it; however, they often do not have the capital or infrastructure to do so. No credit or income is gained from conservation practices, despite the fact that many ejidos are in marginal, nonarable environments where conservation practices are necessary for the sustainability of the ecosystems and agricultural production. Instead, the incentives, opportunities, and loans offered by government programs, private landowners, or entrepreneurs advocate unsustainable practices for their short-term gain at the ejidatarios's and land's expense.

A new type of agricultural revolution is needed to benefit the small-scale farmers of Mexico. Without changing the overall objec-

Suggested Citation:"Mexico." National Research Council. 1993. Sustainable Agriculture and the Environment in the Humid Tropics. Washington, DC: The National Academies Press. doi: 10.17226/1985.
×

tive to produce food for all, the emphasis needs to be on equity and distribution, self-sufficiency, and sustainable land use practices rather than on higher levels of food production. In addition, these efforts need to take into consideration small-scale farmers' needs and aspirations and integrate their knowledge of the agricultural capacity of the local area with conventional scientific research and technological applications. Many traditional practices on rainfed parcels could enhance present research efforts to increase the agricultural capacity of nonirrigated land without degrading the environment. The emphasis must be on sustainable use and land tenure security for the land already under cultivation and the inhabitants already in residence. The pressure to clear the remaining tropical forests will not diminish as long as the surrounding land continues to lose its ability to provide for its poorest inhabitants and as long as those inhabitants are at risk of displacement by extensive land use systems such as cattle ranching. For these reasons, the agricultural capacities of cleared and degraded lands need to be increased or restored, as do the value of small-scale farmers' production and their role in caring for the land for the next generation.

THE FOREST RESOURCES AND DEFORESTATION

The tropical forests of Mexico occur in the coastal lowlands along the Pacific coast between the states of Sinaloa and Chiapas and along the Caribbean Sea from Quintana Roo to the coastal states on the Gulf of Mexico (Table 5 and Table 6). Ecologists have described the forests in the tropics of Mexico and have classified them as several different types (Table 7). The vegetation types in the lowlands range from low thorny tropical forests (less than 10 m high) to the tall evergreen rain forests (more than 30 m high). In the highlands, the vegetation ranges from the tropical cloud forests to the low evergreen tropical forests, also known as elfin forests.

The majority of tropical forests that remain in Mexico can be found on ejidal lands or federal property (Table 8 and Table 9). The states of Campeche, Quintana Roo, Yucatán, and Tabasco were chosen for this analysis because they are not mountainous and contain only tropical forests. The extent of forests on private or government property can be deduced from the data in Table 10. The distinction between private and government property is important because strategies for conservation and sustainable development may be very different for these two main types of land ownership—private and ejidal.

Strategies for developing sustainable land use practices for the tropical forest area of Mexico should be focused on the ejidal lands.

Suggested Citation:"Mexico." National Research Council. 1993. Sustainable Agriculture and the Environment in the Humid Tropics. Washington, DC: The National Academies Press. doi: 10.17226/1985.
×

TABLE 5 Area Covered by High and Medium-Sized Tropical Forest Trees, by State (in Thousands of Hectares)

 

Area (ha)

State

Higha

Mediumb

Campeche

100

2,700

Chiapas

800

1,100

Quintana Roo

350

1,200

Oaxaca

300

500

Veracruz

80

300

Tabasco

10

40

Total

1,640

5,840

a More than 30 m in height.

b 10–30 m in height.

SOURCE: Comisión Nacional Forestal. 1988. Hacia un Programa de Acción Forestal Tropical en México. Propuesta para la Conservación y el Desarrollo de las Selvas del Sureste. México, D.F.: Secretary of the Agrarian Reform, Secretary of Agricultureand Hydraulic Resources, and Secretary of Urban Development and Ecology.

They include more of the forestland and represent the greater challenge for the sustainable development of forestlands in Mexico. Nonetheless, the private lands should not be ignored; improved management practices that include the conservation of ecosystems, flora, and fauna may increase the profitability of these lands while providing conservation benefits.

In this discussion two tropical forest types are relevant: the tall evergreen forests (evergreen forests taller than 30 m) and the tall or medium-height semideciduous forests (forests with some deciduous species taller than 15 m) (Pennington and Sarukhán, 1989). These are the most abundant forests and are the most threatened by agricultural activities. All other forest types cover less land area, although they may be more important from a conservation perspective (Rzedowski, 1978). However, conventional means of protecting areas (for example, parks, reserves, refuges) are more applicable for preservation of these areas than is the development of better systems of conservation and sustainable use.

The state of Chiapas is considered to be one of the greatest centers of biodiversity in northern tropical America because of the quantity (50 percent) of tall tropical forests that remained in 1988 (Toledo, 1988). In the southeastern states of Mexico (21 percent of the country), for example, there are some 7.7 million ha of tropical forests,

Suggested Citation:"Mexico." National Research Council. 1993. Sustainable Agriculture and the Environment in the Humid Tropics. Washington, DC: The National Academies Press. doi: 10.17226/1985.
×

TABLE 6 Forest Area by State and Vegetation Type (in Thousands of Hectares)

 

Area (ha)

State

High Tropical Forestsa

Medium-Sized Tropical Forestsb

Campeche

126

2,836

Chiapas

866

1,226

Colima

0

98

Guerrero

0

244

Hidalgo

0

11

Jalisco

0

161

Michoacan

0

320

Nayarit

0

320

Oaxaca

53

921

Puebla

0

124

Quintana Roo

462

1,206

San Luis Potosi

0

5

Sinaloa

0

980

Tabasco

61

179

Tamaulipas

0

6

Veracruz

513

357

Yucatán

0

298

Total

2,114

9,292

NOTE: Data presented here are based on data from studies done between 1965 and 1987.

a More than 30 m in height.

b 10–30 m in height.

SOURCE: Department of Agriculture and Hydraulic Resources. 1989.México Forestal en Cifras. 1987. México, D.F.: Secretary of Agriculture and Hydraulic Resources.

from which 1.214 million m3 of forest products are produced each year and from which 7 million m3 of firewood is obtained for consumption each year (Comisión Nacional Forestal [National Forestry Commission], 1988). Most of the forests in that region are not well preserved, however (Table 11). The most important remnants of high tropical evergreen forests are found in the Lacandon forest of Chiapas, including the region of Marquéz de las Comillas on the border with Guatemala, where a battle to save the remaining forests is being fought. At present, the winners are cattle ranching and secondary vegetation (Table 11). On the other hand, Campeche contains 46 percent of the medium-size forests and Tabasco has been totally deforested in the last few decades.

Suggested Citation:"Mexico." National Research Council. 1993. Sustainable Agriculture and the Environment in the Humid Tropics. Washington, DC: The National Academies Press. doi: 10.17226/1985.
×
A Definition of Deforestation

The various definitions of deforestation have a lot to do with the different estimates and perceptions of the process (Grainger, 1984; Lugo and Brown, 1981; Melillo et al., 1985). One view refers to the conversion of mature (older) forest ecosystems to less diverse ecosystems, which may mean the loss of pristine forests or virtually undisturbed forests. These mature forest ecosystems contain the greatest biodiversity in the tropics.

A second definition of deforestation includes the conversion of any forest ecosystem to nonforest ecosystem. This includes the conversion of secondary forests, agroforestry lands, and forest plantations to nonforest ecosystems, such as grasslands or other treeless agricultural systems. The concern is more for the known and potential roles that forest ecosystems play—in soil conservation, provision of forest products, and the earth's carbon dioxide balance—than for the roles they play in conserving biodiversity. This second type of deforestation is usually less important in the humid tropics, since it can be reversed in many cases. Forested land cleared for shifting agriculture can again become forest in a few years.

Evaluation of deforestation is difficult, however, because most studies are done by using aerial photographs or satellite images, and the distinction between the two types of deforestation given above is difficult to make by using aerial photographs or satellite images. The only clear distinction that can be made is that between forested and

TABLE 7 Ecosystems of Mexico for 1500 and 1985

 

Total Area of Mexico (%)

Ecosystem

1500

1985

Percent Change

High and medium-sized tropical forests

15

3

−80

Low tropical and thorn forest

14

20

+43

Pine-oak forest

20.4

15

−26

Mesophyll forest

0.5

0.1

−80

Pasture / grasslands

10

15

+50

Desert

40

47

+18

Suggested Citation:"Mexico." National Research Council. 1993. Sustainable Agriculture and the Environment in the Humid Tropics. Washington, DC: The National Academies Press. doi: 10.17226/1985.
×

NOTE: High tropical forests, more than 30 m in height; medium-sized tropical forests, 10–30 m in height.

SOURCE: Fundación Universo Veintiuno. 1990. Desarrollo y Medio Ambiente en México. Diagnóstico, 1990. México, D.F.: Friedrich Ebert Stiftung.

TABLE 8 Ejidal Land in Mexico

     

Area (in hectares)

State

Area of State (km2)

Number of Ejidos

Ejidal Land

Agriculture

Forests

Grasslands and Secondary Forest

Cities, Roads, etc.

Campeche

50,812

344

3,115,750

339,722

1,651,522

1,092,536

31,970

Quintana Roo

50,212

270

2,743,286

339,352

1,698,890

703,825

1,219

Tabasco

25,267

694

1,011,991

232,189

94,684

568,080

117,038

Yucatán

38,402

718

2,162,147

561,450

270,168

1,071,637

258,892

SOURCE: National Institute of Statistics, Geography, and Information(Instituto Nacional de Estadística Geografía e Informática). 1990a. XI Censo General de Población y Vivienda. Aguascalientes, México: Instituto Nacional de Estadística Geografía e Informática.

Suggested Citation:"Mexico." National Research Council. 1993. Sustainable Agriculture and the Environment in the Humid Tropics. Washington, DC: The National Academies Press. doi: 10.17226/1985.
×

TABLE 9 Distribution of Tropical Forests by State, 1987 (in Thousands of Hectares)

 

Area (ha)

State

High Tropical Forestsa

Medium-Sized Tropical Forestsb

Campeche

100

2,700

Chiapas

800

1,100

Quintana Roo

350

1,200

Oaxaca

300

500

Veracruz

80

300

Tabasco

10

40

Yucatán

200

Sinaloa

700

Nayarit

300

Michoacan

250

Guerrero

200

Jalisco

100

Puebla-Queretaro

100

Hidalgo

10

San Luis Potosi

5

Tamaulipas

5

Total

1,640

7,710

a More than 30 m in height.

b 10–30 m in height.

SOURCE: Comisión Nacional Forestal. 1988. Hacia un Programa de Acción Forestal Tropical en México. Propuesta para la Conservación y el Desarrollo de las Selvas del Sureste. México, D.F.: Secretary of the Agrarian Reform, Secretary of Agricultureand Hydraulic Resources, and Secretary of Urban Development and Ecology.

unforested lands, that is, the degree of forest cover. The process is also complicated by the rapid succession rate that is possible in the humid tropics. Within 10 to 15 years, it is possible to develop a forest that is dominated by secondary-growth trees on cleared land (Gómez-Pompa and Vázquez-Yanes, 1981). The process is continuous in these areas, and the changes through time can be dramatic (Estrada and Estrada, 1983). For these reasons, deforestation and reforestation figures should be considered as approximations. Ground surveys are essential for more accurate assessments of the nature and type of deforestation and the changes in species composition that are occurring. In this profile, deforestation rates are mostly derived from the literature and include both types of deforestation described above. The information available from these sources is sufficient to evaluate the degree of conversion and to estimate the rates of deforestation.

Suggested Citation:"Mexico." National Research Council. 1993. Sustainable Agriculture and the Environment in the Humid Tropics. Washington, DC: The National Academies Press. doi: 10.17226/1985.
×

TABLE 10 Ownership of Tropical Forests in Selected Tropical States (in Hectares)

State

Total Area of Tropical Forests (1970)a

Ejido Forests (1988)b

Private Ownership and Estate Communities

Campeche

2,642,000

1,651,522

990,478

Quintana Roo

3,358,000

1,698,890

1,659,110

Tabasco

358,000

94,684

263,316

Yucatán

454,000

270,168

1,245,832

NOTE: Data are calculated from vegetation map and land use map produced by Annex 2.1 in Secretaria de Programación y Presupuesto. 1981. Carta de vegetación y uso actual del suelo esc. 1:100,000. In Atlas Nacional del Medio Físico. México, D.F: Secretaría de Programación y Presupuesto.

a SOURCE: Toledo, V. M., J. Carabias, C. Toledo, and C. González-Pacheco. 1989. La Producción Rural en México: Alternativas Ecológicas. Número 6. México, D.F.: Siglo XXI Editores.

b SOURCE: National Institute of Statistics, Geography, and Information. 1990b. México, D.F.: El Sector Alimentario en México. Instituto Nacional de Estadistico. Geograria e Inform ática and Comisión Nacional de Alimentación.

Current Estimates of Deforestation

Although Mexico is always included in the list of countries with the most rapid rates of deforestation, precise data to support this claim do not exist. The best-known source to date has been a report of the Food and Agriculture Organization (FAO) of the United Nations and United Nations Environment Program (UNEP) (1981), which places Mexico third in Latin America with a deforestation rate of approximately 500,000 ha/year from 1981 to 1985.

Toledo's estimates (1988), which are probably the best available, challenged the FAO and UNEP estimates, arguing that the growth rate of cattle grazing areas and the expansion of the agriculture frontier is much greater than the FAO and UNEP figures suggest. Using the information from the 1980 census (Toledo, 1988) and inventories of land use and cattle grazing, Toledo projects a deforestation rate of about 1.1 million ha/year. If the areas destroyed by forest fires and forestlands cleared for new agricultural activities are added, defores-

Suggested Citation:"Mexico." National Research Council. 1993. Sustainable Agriculture and the Environment in the Humid Tropics. Washington, DC: The National Academies Press. doi: 10.17226/1985.
×

TABLE 11 Changes in Land Use in the Lacandon Rainforest of Chiapas

 

Area in ha (percent of total area)

Land Use

1973

1981

Percent Change

Well-conserved vegetation

76,526 (35)

−100

Secondary vegetation

59,963 (26)

141,500 (65)

148

Agriculture

67,388 (31)

32,700 (15)

−52

Cattle ranching

43,500 (20)

100

SOURCE: Department of Agriculture and Hydraulic Resources. 1984.Comisión del Plan Nacional Hidráulico. Desarrollo Rural Integrado de la Selva Lacandona. México, D.F.: Secretary of Agriculture and Hydraulic Resources.

tation could reach 1.5 million ha/year, which is 3 percent of the total forestland in Mexico (Toledo, 1988).

The current total forest area in Mexico is unknown. In the 1970s, Mexico had 80 million ha of basically unperturbed forest (Toledo, 1988). If Toledo's estimates are correct, the total forest area of approximately 80 million ha in the 1970s was reduced to 65 million ha by 1990 and will drop to 35 million ha by the end of the century if the trend is not slowed, stopped, or reversed.

Of its total land area, Mexico has 30,870,555 ha of tropical forests (INEGI, 1990b). They include forests that range from low deciduous tropical forests to tall evergreen tropical forests. There are, however, different estimates of the forested area and the deforestation rate in Mexico, as follows:

  • Rzedowski (1978) estimated that 90 percent of the forests in the lowland humid tropics of Mexico were eliminated by the 1970s.

  • According to Toledo et al. (1985), these forests probably occupied 15 million ha—approximately 8 percent of the total land area of Mexico —in the past.

  • The best-known figures are those published in 1990 by the World Resources Institute (WRI). The data is based on the and other reports (Food and Agriculture Organization and United Nations Environment Program, 1980, 1981, 1988; Lanly, 1982, 1989). According to these reports, in 1980 the forest resources of Mexico covered 48,350,000 ha, including 46,250,000 ha of closed-canopy forests and 2,100,000 ha of open-canopy forests. The annual deforestation rate was 615,000 ha, or 1.3 percent of the total forest. The average annual area reforested was only 28,000 ha/year in the 1980s (World Resources Institute, 1990).

  • According to the Tropical Forest Action Plan for Mexico (Comisión Nacional Forestal, 1988), there was 37 million ha of forested areas in Mexico between 1986 and 1987, which was nearly 11 million ha less than in 1980. Of these, 9.3 million ha is tropical forest. Of this area, 6 million ha is considered productive, with potential for exploitation. The other 3.3 million ha has an ecologic rather than an economic value and includes parks, reserves, and other protected areas.

Suggested Citation:"Mexico." National Research Council. 1993. Sustainable Agriculture and the Environment in the Humid Tropics. Washington, DC: The National Academies Press. doi: 10.17226/1985.
×

TABLE 12 Land Use in Humid and Subhumid Tropics in Mexico, 1981 (in Hectares)

Ecological Zone

Total

Agriculture

Forests

Cattle Grazing

Uses

Combined Others

Humid tropics

20,144,137

20,143,445

11,696,263

3,789,220

724,972

1,213,000

Subhumid tropics

32,576,050

32,575,823

14,578,467

2,867,426

6,594,553

788,000

Total

52,720,187

52,719,268

26,274,730

6,656,646

7,319,525

2,001,000

NOTE: Data are abstracted from the VI General Agricultural, Cattle and Ejidal Census, 1981.

SOURCE: Toledo, V. M., J. Carabias, C. Toledo, and C. González-Pacheco. 1989. La Producción Rural en México: Alternativas Ecologiás. No. 6. México, D.F.: Siglo XXI Editores. Taken from Annex 6.1, p. 293.

Suggested Citation:"Mexico." National Research Council. 1993. Sustainable Agriculture and the Environment in the Humid Tropics. Washington, DC: The National Academies Press. doi: 10.17226/1985.
×

No reliable figures for the forests in the Mexican humid tropics can be found, but combining the values of humid and subhumid forests from Table 12, more than 26 million ha of tropical forests existed in 1981, nearly half of the forested land in Mexico at that time. This estimate may be misleading because the deforestation rate has been faster in the tropics than in the other climatic regions of Mexico. By using Toledo 's (1988) indirect method, it can be estimated that the number of cattle in the tropical states of Campeche, Chiapas, Quintana Roo, and Tabasco increased markedly since the 1970s to the 1980s. The deforestation cycle of lumber or mineral extraction followed by colonization, land acquisition, and conversion to pasture for cattle is well known in Mexico (Gómez-Pompa, 1987b). For this reason, an increase in the number of cattle entering the tropics implies that the deforestation rate in tropical areas is greater than the deforestation rate in all of Mexico.

The area deforested in the states of Chiapas, Tabasco, Campeche, and Quintana Roo between 1984 and 1989 was approximately 1 million ha of a total forested area of approximately 20 million ha, an average annual loss of 167,000 ha of forest. This is in contrast to Toledo 's (1988) estimate of 1.5 million ha per year for the entire forested area of Mexico (200 million ha). The states considered here make up one-tenth of the country's total area (20 million ha), and the deforestation rate in the tropics (5 percent) is slightly higher, yet it is consistent with those for the country as a whole (4.5 percent). Although these calculations need to be checked against aerial photography or satellite images, they correspond well with more qualitative estimates and document the amount of deforestation in the Mexican humid tropics.

If these estimates are correct, the small remnants of tropical forests that existed in Tabasco, Veracruz, and Oaxaca in the late 1970s have vanished. This conclusion can only be confirmed if reliable forest inventories are undertaken. An indirect way to document environmental change would be to ask people, who live and routinely travel in these areas, about changes in the forest cover over time.

The loss of species in the humid tropics is also debatable, since no reliable inventories or national biological surveys exist. Toledo

Suggested Citation:"Mexico." National Research Council. 1993. Sustainable Agriculture and the Environment in the Humid Tropics. Washington, DC: The National Academies Press. doi: 10.17226/1985.
×

(1988) suggests that deforestation along with selective extraction of rare plant species for the international market has led to the extinction of at least 17 species and that 477 species are currently endangered. This represents 17 percent of the flora of Mexico.

Causes of Deforestation

Deforestation is the consequence of many processes and actions. The predominant factors, which are described in detail below, include cattle ranching, colonization projects, forest fires, disputes over tree ownership and land tenure, national security, local farming and intensive commercial agriculture, timber exploitation, and road building and other engineering works.

CATTLE RANCHING

Cattle ranching has been the most important cause of deforestation (Table 13) (Denevan, 1982; Myers, 1981; Shane, 1980). In Mexico, the following are some of the avenues and incentives by which forests are converted to pastures for cattle grazing (Denevan, 1982):

  • Direct clearing,

  • Contracted shifting cultivation,

  • Contracted deforestation,

  • Land consolidation,

  • Small ranches,

  • Large ranches,

  • Land tenure (in Mexico, by law, there is a maximum number of hectares of agricultural or cattle land that can be allotted to any one person),

  • Economic viability of the land,

  • Poor understanding of environmental processes and actions,

  • Inadequate enforcement of regulations for environmental protection,

  • National markets,

  • U.S. and international markets,

  • National financial incentives, and

  • International financial incentives.

Cattle raising activities have been a key factor in deforestation for several reasons:

  • There is an open market (national and international) for beef products, which creates increased incentives for conversion of forests to pasture land.

  • Cattle ranching is a relatively simple operation that can be managed by only a few people per hectare and administered from a distant location.

  • Lines of credit for cattle ranching are available and offered as incentives.

  • Cattle ranching enterprises are given preferential treatment in government regulations and protected by the government.

  • A long cultural tradition—with roots in Spain and Portugal—identifies cattle ranchers as persons of status and respect, regardless of their actual production and profit.

Suggested Citation:"Mexico." National Research Council. 1993. Sustainable Agriculture and the Environment in the Humid Tropics. Washington, DC: The National Academies Press. doi: 10.17226/1985.
×

TABLE 13 Grazing Areas and Cattle in Chiapas

Year

Number of Head

Grazing Area (ha)

Variation in Grazing Area from Previous Year

1982a

3,391,839

4,409,391

1983a

3,422,141

4,448,783

39,392

1984a

3,056,998

3,974,097

1985

3,072,954

3,994,840

20,743

1986

3,104,083

4,035,308

40,468

1987

3,150,644

4,095,837

60,529

1988b

2,942,103

NOTE: Total area of Chiapas is 7,441,500 ha.

a SOURCE: Instituto Nacional de Estadística Geografía e Informática. 1990b. El Sector Alimentario en México. México, D.F.: Instituto Nacional de Estadística Geografía e Informática and Comisión Nacional de Alimentación.

b SOURCE: Instituto Nacional de Estadística Geografía e Informática. 1990c. Anuario Estadístico del Estado de Chiapas. México, D.F.: Instituto Nacional de Estadística Geografía e Informática.

COLONIZATION PROJECTS

The perception of tropical forested areas as agricultural frontiers has strongly influenced development policies in Mexico (Department of Agriculture and Hydraulic Resources, 1987; Parsons, 1976; Partridge, 1984). At one time, many deforested lands were federal lands that the government used to alleviate the need for land by landless peasants (Gómez-Pompa, 1987b).

The new areas of colonization are “prepared” for the peasants by use of government funds (frequently backed by loans from international banks) that give concessions for valuable wood to selected con-

Suggested Citation:"Mexico." National Research Council. 1993. Sustainable Agriculture and the Environment in the Humid Tropics. Washington, DC: The National Academies Press. doi: 10.17226/1985.
×

tractors. These contractors construct or use the roads paid by the government, “mine” the wood, and sell it on the national market. In the past, the wood was also sold on the international market.

The areas granted to the campesinos are the ones where the valuable wood has already been extracted. Land that is not distributed to potential ejidatarios is signed over to a forest-clearing contractor through the National Commission of Deforestation of the federal government. By this process, many new lands also fall into private hands or are left unassigned. Squatters take temporary possession of unassigned lands for subsistence agricultural activities. The land is later converted to private land, primarily for cattle ranching. At times, the beneficiaries are the squatters, but more frequently they are influential people—state governors, military officials, local political strongmen, and “city cattlemen” (those who run cattle ranching operations from urban areas).

FOREST FIRES

Natural and anthropogenic forest fires also contribute to deforestation in the Mexican humid tropics. A fire in Chiapas during 1982 burned 600,000 ha, and another in Quintana Roo in 1988 burned 1,200 ha (L ópez Portillo et al., 1990).

Fire is often the cheapest, most efficient tool available to small-scale farmers for clearing an area for agriculture. Farmers can be divided into two main categories: those who have legal rights to their property and those who do not (Gómez-Pompa, 1987b). The first group usually uses fire as part of their shifting cultivation activities. They have detailed knowledge of when and how to use the fire, how to burn the slash and the fallen trees, and the necessary techniques to guide and control the fire. It is rare for a forest fire set by shifting cultivators to extend outside the area of the forest that has been cut.

Agriculturalists without legal rights to the land realize that the area does not belong to them and that there is a high probability that they will lose it. Therefore, their burning is done with little care or foresight. These farmers are usually newcomers to the area and have limited knowledge of management that is appropriate for the area. Their primary goal is simply to produce enough food for their families to survive. The clearing of trees provides a “cleaned ” area for the cattle ranchers when the colonizers abandon or are evicted from the land. Forest burning by shifting cultivators has received most of the publicity and blame for deforestation. The International Rice Research Institute (1992) claims that shifting cultivation accounts for

Suggested Citation:"Mexico." National Research Council. 1993. Sustainable Agriculture and the Environment in the Humid Tropics. Washington, DC: The National Academies Press. doi: 10.17226/1985.
×

an estimated 30 percent of deforestation in Latin America; but government policies and the interests of cattle ranchers are behind this process.

PROBLEMS OF TREE OWNERSHIP AND LAND TENURE

One of the most neglected issues with regard to deforestation is tree and forest ownership and land tenure. Tree ownership is a long tradition in many non-Western cultures, but it is not well recognized or accounted for in development programs. According to Fortmann and Bruce (1988:5),

Most forestry and agroforestry initiatives are based either on the premise that rural people will plant trees or that they will preserve and protect trees planted by someone else including the government. However, people do not preserve, protect or plant trees nor allow others to, if doing so is costly to them personally. Tree species planted by government offices are unlikely to have a high survival rate on private or community land.

Home gardens, consisting of tropical forest trees, are often the only forested areas left. These trees are planted, maintained, managed and protected by the people in whose household gardens the trees grow. The key component of the home gardens is that they belong to the household, and household members select and manage the trees they want.

Who, ultimately, has the tenure rights to the forests? Local inhabitants of the forest have always believed that the forest “belongs” to them because they have the same rights to use it as their parents and grandparents had before them. However, they are now learning that the land and its resources belong to the nation and that the government is empowered to give concessions for timber extraction or other uses to outsiders. In Mexico, this forest tenure conflict has been resolved by applying a fee per hectare or per volume of wood that is paid by concessionaires to individuals or communities as forest rights. This is usually only a token offering when compared with the value of the tropical woods on the national and international markets.

NATIONAL SECURITY

Mexico has cleared extensive areas of forest on its border with Guatemala to facilitate colonization of those areas. These colonies form a human shield to protect and buffer the country from political refugees fleeing the Guatemalan army.

Suggested Citation:"Mexico." National Research Council. 1993. Sustainable Agriculture and the Environment in the Humid Tropics. Washington, DC: The National Academies Press. doi: 10.17226/1985.
×
AGRICULTURE

Some large-scale agriculture projects and the consequent clearing of large tracts of land have been of importance in the Mexican tropics. The only extensive agricultural system involved in discussions of deforestation is shifting agriculture. However, it should not be assumed that shifting agriculture is a cause in deforestation; rather, it should be considered a silvicultural technique when it is practiced under the appropriate conditions (for details see Gómez-Pompa et al., 1991; Ramakrishnan, 1984). Shifting cultivators who have ample knowledge of local conditions and species, skilled labor, and a commitment to long-term maintenance of their families and communities may also play a key role in the implementation of sustainable resource management practices.

INTENSIVE COMMERCIAL AGRICULTURE

Intensive commercial agriculture plays a minor role in deforestation when one considers the total land area covered. It typically involves commercial farming—usually perennial bush and tree crops—on permanent fields (Denevan, 1982). The major crops grown on these fields include coffee, cacao, rubber, sugarcane, pineapple, cotton, coconut, and mango. During the late 1800s, considerable areas were cleared for henequen (a fiber used to make binder twine). The amount of land used to grow avocado, melon, pineapple, watermelon, coconut, lemon, mango, orange, and banana was 372 ha in 1970 and 503 ha in 1980. Total production of these crops was 3.98 and 6.32 million metric tons in 1970 and 1980, respectively.

TIMBER EXPLOITATION

The valuable tropical woods of Mexico have already been largely depleted. For example, only in the remote and inaccessible areas—which are rarely found—is it possible to find mahogany. The contribution of timber exploitation to deforestation is not so much from the select logging of valuable trees as from the roads timber exploitation creates and the secondary damage that results from harvesting the desired species. Therefore, the starting point of deforestation is timber extraction, which is followed by the clearing of the remaining trees for agricultural fields by incoming landless peasants. These fields eventually become grasslands or secondary forests.

Suggested Citation:"Mexico." National Research Council. 1993. Sustainable Agriculture and the Environment in the Humid Tropics. Washington, DC: The National Academies Press. doi: 10.17226/1985.
×
ROAD BUILDING AND OTHER ENGINEERING WORKS

Another cause of deforestation is the opening of new roads for oil exploration, lumber extraction, communication, or domination. Roads allow improved access to forested lands for colonizers.

Protected Areas

The protected areas of Mexico did not include tropical forest areas until the late 1970s. At present, the total area of protected closed forests has been estimated to be 360,000 ha (World Resources Institute, 1990). In 1989, Mexico had six biosphere reserves—Sian Ka'an, Montes Azules, El Cielo, Sierra de Manatlán, Mapimí, and Michilía—encompassing 1,288,454 ha, and 47 protected areas (excluding the Marine and Coastal protected areas) covering 5,582,625 ha (World Resources Institute, 1990). A recent survey (Ecosfera, 1990) showed a total of 308 protected areas in the Maya region. Seven percent of the total land area is under some form of protection as parks, reserves, or refuges. However, designation as a protected area does not necessarily ensure that it will be protected. The areas that are actually protected, in terms of the prevention of deforestation in core or buffer zones, is considerably below 7 percent.

SUSTAINABLE RESOURCE MANAGEMENT

Sustainable resource management activities range from gathering forest products at one extreme to a conventional agricultural system that is energy and petrochemical intensive at the other. Many of the changes and improvements that have or will be developed and tested will be of value to farmers across this full spectrum.

A Definition of Sustainability

There is no universally accepted definition of sustainable resource management. Some definitions are philosophically based, others address economic issues, whereas others specify management practices. Resource management can be said to be economically sustainable when supply matches demand and reasonable profits are made; ecologically sustainable when practices are environmentally sound and enhance rather than degrade the natural resource base; and culturally sustainable when farmers, families, communities, and the fabric of rural life remain viable. (For a more detailed discussion of the many different concepts and practices, see Bainbridge and Mitchell, 1988.)

Suggested Citation:"Mexico." National Research Council. 1993. Sustainable Agriculture and the Environment in the Humid Tropics. Washington, DC: The National Academies Press. doi: 10.17226/1985.
×

Although economics and ecologic sustainability are often the only components discussed in sustainable resource management, a definition that also includes cultural sustainability is better because the maintenance of a viable culture, although perhaps the most challenging element, is in many ways the most important one. Farmer's knowledge, effort, and investment of energy and time are critical to sustainable resource management, and in return for their efforts they should be able to anticipate a better future. The family, the community, transportation links, and suppliers are also essential for sustainable resource management.

The ecologic basis for sustainability is also critical. If the ecologic foundation deteriorates, there is little chance of maintaining a long-term production capability. Although some restoration efforts have been successful, the rehabilitation costs can be many times higher than the immediate economic return. Therefore, it is much easier to avoid ecologic decline than to reverse it.

Environmentally sound production practices will help to bring real production costs down and improve profitability. This can provide farm families and communities with the incomes they need to survive and provide the stability needed to improve rural services—education, health care, transportation, utilities, and water.

Sustainable resource management can be achieved with existing equipment and facilities, conventional crops, and traditional markets. It requires more accurate knowledge and precise management of on-farm and off-farm resources to minimize production costs, maximize production efficiency, improve quality and grade of products, and reduce adverse environmental impacts. Improved planning and marketing will more closely match production to demand and will enable farmers to retain a larger share of retail cost rather than lose much of the value of their products to middlemen—transporters, distributors, storage, and retailers.

Small-scale subsistence farmers are concerned with sustaining their households, usually under severe economic constraints. Whereas large-scale commercial farmers are concerned with maximizing profits, small-scale farmers are often more concerned with minimizing risk. For each type of farmer, the importance and consequences of sustainability will be different. For subsistence farmers, a sustainable agriculture system must include self-sufficiency in the production of food and a variety of other products they and their household need (for example, firewood); sustainability for commercial farmers implies continued profitability through the extensive production of foods or commodities for sale to large markets. Each type of farmer usually allocates a wide range of resources—time, labor, and capital—very efficiently in

Suggested Citation:"Mexico." National Research Council. 1993. Sustainable Agriculture and the Environment in the Humid Tropics. Washington, DC: The National Academies Press. doi: 10.17226/1985.
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pursuit of these goals. Revising incentives and benefit structures to reward sustainable practices can lead to the rapid adoption of new technologies for both subsistence and commercial farmers.

The international food and commodity markets are highly competitive, and government interventions and regulations distort prices and production in most countries. Prices of commodities are often subsidized at levels above competitive world prices, and commodities purchased by the government under these programs may be dumped in the world market and sold at prices far below the actual cost of production. Improving the accounting practices to include environmental costs, for example, erosion and land degradation, would do much to improve resource production and move production to areas where it is most efficient economically and ecologically.

Agricultural sustainability must be addressed not only from the personal perspective of the farmer's needs and resources but also from the national perspective of the country's needs and resources. Many small-scale solutions will eventually combine to contribute to global agricultural sustainability.

Sustainable Resource Management Practices in the Mexican Humid Tropics

An evaluation of sustainability can be made for virtually any resource management practice in the humid tropics of Mexico, from extensive cattle ranching on cleared forestlands to cattle production in feedlots, or from the manual labor of shifting agriculture to equipment-intensive timber production (Table 14). Sustainability is not inherent in scale, labor input, or management intensity, but rather reflected in the combined effects of many aspects of a particular agricultural system. The application of biodegradable pesticides by peasants without suitable protection (respirators and protective clothing) and management of contaminated containers and waste material cannot be considered sustainable because of the high risk to human health. Yet this same material could be used in a sustained manner if the materials were carefully controlled and the users and community were properly protected. In terms of shifting agriculture, short fallow periods are likely to be unsustainable as soil fertility gradually declines; but shifting agriculture with a sufficient fallow period (often 10 to 15 years) can be maintained indefinitely as the leguminous trees and shrubs restore soil fertility. Raised field beds in swampy areas could be sustainable, but only with a corresponding master hydraulic plan to regulate water quality and water levels.

The sustainability of any agricultural system can be enhanced by

Suggested Citation:"Mexico." National Research Council. 1993. Sustainable Agriculture and the Environment in the Humid Tropics. Washington, DC: The National Academies Press. doi: 10.17226/1985.
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TABLE 14 Comparison of Four Primary Production Systems

Production System

Annual Production

Value (millions of 1986 pesos/yr)

Number of Jobs Created

Characteristics

Shifting agriculture

180,000 metric tons of maize

1,800

50,000

High number of nonsalaried jobs; provides subsistence to high numbers of people; if done well, has high conservation and ecologic values

Cattle ranching

7,800 metric tons of cattle

4,600

300

Low number of jobs generated; benefits a reduced number of people; low conservation or ecologic values

Potential forest production

200,000 m3 unprocessed trunks

6,000

3,500

Potential for new production jobs; increased monetary rewards for owners; trunks high conservation and ecological values if done properly

Sustainable agriculture

Potential for generating productive jobs, capitalization of farmers, if done properly; has high ecological value

SOURCE: Modified from Comisión Nacional Forestal. 1988. Hacia un Programa de Acción Forestal Tropical en México. Propuesta para la Conservación y el Desarrollo de las Selvas del Sureste. México, D.F.: Secretary of the Agrarian Reform, Secretary of Agricultureand Hydraulic Resources, and Secretary of Urban Development and Ecology.

using appropriate techniques. In some cases this may require the use of organic fertilizers; in others, chemical fertilizers. It may also include biologic controls instead of chemical pesticides. In some systems intercropping and rotations might be appropriate, whereas in other systems several combinations of mixed cropping in time and space may be appropriate. It is often easier to balance energy and nutrient demands and flows in mixed cropping systems that include animals and poultry than it is to balance those with only plants.

Some agricultural systems are easier to make sustainable than others, but those systems may not meet the basic needs of the household or the nation. For example, the extractive uses often mentioned as an option for forest reserves may provide limited resources for a few people but not for a larger population. Each agricultural system has its idiosyncracies and should be treated differently. It is more

Suggested Citation:"Mexico." National Research Council. 1993. Sustainable Agriculture and the Environment in the Humid Tropics. Washington, DC: The National Academies Press. doi: 10.17226/1985.
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challenging to develop sustainable systems for an area with 500 people per km2 than it is for an area with only 5 people per km2. An appropriate set of management strategies and practices (for example, crop selection, markets, inclusion of large or small livestock, and labor requirements) must be developed for each agricultural system, although there may be some overlap between related production systems in similar environmental settings.

This leads to the larger problem of developing and managing the biosphere in a sustainable manner. The pollution of air, land, and water; the depletion of biological diversity; and increased deforestation indicate that modern society has not mastered resource management (McNeeley et al., 1990). The loss of biodiversity will not be solved by recommendations for sustainable agricultural approaches or major reforestation programs because the loss of biodiversity and other problems in the biosphere are affected by the cumulative effect of individual actions and responses to the economic and political incentives for clearing and using forested land. The reports and programs are essential, but they must be linked and related more directly to market incentives and factors that influence individual decision making at the most basic level of the smallest farm and family plot.

Lessons from Traditional Resource Management

There are already many traditional resource management approaches that can help in the search for sustainable agricultural production in Mexico (Altieri, 1987; Wilken, 1987). The relationship between traditional cropping practices and the control of pests—both insects and weeds—has been discussed in numerous articles (Altieri and Merrick, 1987; Gliessman et al., 1981). Management of organic matter (mulches, compost, and manures) helps to conserve nutrients, as do traditional methods of soil and water conservation (Wilken, 1987).

Many of these practices can be improved with scientific knowledge and technology and should be considered in the development of viable alternatives. It is essential, however, to begin with a detailed understanding of the motivations, practices, and needs of the local people. Only then can appropriate technologies begin to be developed. This is in contrast to the typical approach, by which the technology is developed first, without considering the cultural aspects.

It is also important to acknowledge environmental constraints. Traditionally, enormous expenditures have been made to fit the environment to the crop. The growing recognition of a wide range of useful crops (local, traditional, and global), however, makes it in-

Suggested Citation:"Mexico." National Research Council. 1993. Sustainable Agriculture and the Environment in the Humid Tropics. Washington, DC: The National Academies Press. doi: 10.17226/1985.
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creasingly easy to select a crop that fits the environment. In addition, more research is needed to explore the wide range of potential products that can be extracted from the tropical forests of Mexico.

One of the most striking features that has emerged from research in the humid tropics of Mexico is the importance of human intervention and management in the development of the forests in that region, which were previously considered untouched, pristine, and certainly unmanaged (Gómez-Pompa and Kaus, 1990). These traditional agroforestry systems are valuable resources that have been developed and refined over the centuries. They are invaluable knowledge banks for understanding and improving tropical forestry management and should be studied before they disappear. Some traditional systems have been studied (Alcorn, 1984, 1990; Flores Guido and Ucan Ek, 1983; Gómez-Pompa, 1987a; Nations and Komer, 1983), but much remains to be learned.

THE LOWLAND MAYA

An alternative approach to tropical forest management, described in this profile, has been shaped by on-going work with Maya groups in Mexico (Gómez-Pompa, 1987a; Gómez-Pompa and Bainbridge, 1991), whose ecologically sophisticated forest management practices have provided many important lessons based on long-term experience with the surrounding ecologic and sociocultural systems. The ecologic complexity of the Maya forests is clear, both in the numbers of species and in their temporal and spatial arrangement (Gómez-Pompa, 1987b; Rico-Gray et al., 1988). Many Maya farmers have detailed knowledge of plants and soils and the regeneration process, which they use in their management of trees and forests.

Evidence from archeological and historical research suggests that in ancient times, agroforestry (combining trees that provide food, fodder, medicine, and building materials with annual and perennial crops, animals, and poultry) may have provided much of the basic needs of people in the densely populated regions of the Yucatán Peninsula. Forest management by the Maya included a variety of methods and techniques, many of which are still practiced. They do not, however, practice the integrated systems believed to have existed in pre-Hispanic times (Gómez-Pompa, 1987a). Past and present Maya agroforestry consists of the protection, cultivation, selection, and introduction of trees in the milpas, fallows, plantations, natural forests, forest gardens (a combination of trees, annual crops, and animals within a limited area around the house), as well as protected forest networks along trails, cenotes (sink holes in limestone with a pool at

Suggested Citation:"Mexico." National Research Council. 1993. Sustainable Agriculture and the Environment in the Humid Tropics. Washington, DC: The National Academies Press. doi: 10.17226/1985.
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the bottom, found especially in Yucatán), and towns (Gómez-Pompa, 1987a; Gómez-Pompa and Kaus, 1987, 1990; Lundell, 1938).

One of the most striking features of present day Maya towns is the abundance of useful trees in the forest gardens: approximately 60 to 80 species in a family plot and some 100 to 200 species in a village (Herrera Castro, 1990). The trees of the forest gardens provide building materials, firewood, food and beverages, medicine, and fodder. Many of the more common trees are the same species found in the surrounding natural forests, although new species—such as papaya, guava, banana, lemon, orange, and other citrus fruit trees—have also been incorporated. Both indigenous and exotic species of herbs, shrubs, vines, and epiphytes grow in the patches of sunshine on the ground or in the shade of the trees. Useful wild species that appear in managed areas are often not weeded out and become established in these gardens. The importance of forest gardens in Yucatán can be calculated as follows. Approximately 25 percent of the Yucatán population has a forest garden. The average plot size is 400 m2. Thus, the combined forest area of these gardens may be more than 25,000 ha, adding almost 10 percent to the forested area of Yucat án.

The Maya also plant or protect trees along the edges of or scattered throughout their agricultural fields. Many of these trees are nitrogen-fixing species (for example, Acacia spp., Leucaena spp., Mimosa spp.), and the abundance of these species may reflect centuries of human selection and protection (Flores Guido, 1987). These nitrogen-fixing trees provide most of the nitrogen required to maintain soil fertility under intensive high-yield cultivation practices.

The use of leguminous trees as shade trees for cacao was a pre-Hispanic practice that is now used on coffee plantations (Cardós, 1959; Jim énez and Gómez-Pompa, 1981). Shaded coffee plants produce fewer coffee beans on an annual basis, yet the shade adds many years to the useful life of the coffee plants.

Other agroforestry techniques are also incorporated into the management of milpas, including the selection and protection of useful individual plants on the site selected for cultivation. The protected species are determined by the interest, knowledge, and needs of the farmer, a factor that helps to explain the high level of biodiversity found on fallow lands and older (20 to 50 years) secondary forests. Even the manner in which trees are cut affects the survival of the forest. If regrowth is allowed to begin from a high trunk (coppicing), the survival rate is improved and is a key factor in the succession process. Although only about 10 percent of the trees may be coppice starts, they may account for more than 50 percent of the biomass during the recovery phase (Illsley, 1984; Rico-Gray et al., 1988).

Suggested Citation:"Mexico." National Research Council. 1993. Sustainable Agriculture and the Environment in the Humid Tropics. Washington, DC: The National Academies Press. doi: 10.17226/1985.
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The conservation of strips of forest along trails and surrounding milpas is also important. This strip probably plays an important role in the regeneration of fallow lands (Remmers and de Koeyer, 1988), provides valuable shade on the trails, and interlinks fragments of the forest so that wildlife has access to all parts of a forest. Studies by Thomas Lovejoy in the Amazon have shown that links between patches of forest increase the effective size of the forest and help to maintain species diversity. They may also play a critical role in maintaining deer, birds, and other game, which are valuable food sources for Maya hunters.

Although some researchers (Abrams and Rue, 1988; Morley, 1946) contend that the collapse of the Maya was caused by misuse of the environment, recent research (Barrera-Vázquez, 1980; Bowers, 1989) supports Thompson 's (1954) earlier suggestion that the collapse of the Maya resulted from increased hostilities and warfare. Trees would be vulnerable to intense warfare. Present-day practices that are similar to those used by the Maya during the pre-Hispanic era indicate that sustained use of the tropical forest would have been possible for a long period of time.

The regeneration of the ecosystems of the Maya area after successive abandonments, the last one occurring after the Spanish conquest, was possible only because seed banks existed in the managed and protected natural ecosystems of the area (Gómez-Pompa et al., 1972), and land use did not cause irreparable harm to the soils.

THE LACANDON MAYA

The forest management of the Lacandon Maya incorporates many of the same practices incorporated by the Yucatec Maya. In the midst of the forest can be found complex agroforestry systems that may include 75 crop species, including fruit trees, in multicanopied single hectare plots (Nations and Komer, 1983). The plot is repeatedly harvested until it is engulfed by the forest, and then a new milpa plot is started.

THE HUASTEC MAYA

The Huastec Maya of northeast Mexico manage the humid forest in a manner that combines commercial and subsistence production (Alcorn, 1984). As many as 300 species may be found in a plot that provides food, construction materials, fuelwood, fodder, medicine, and chemicals. The forest plots are an important adjunct to the agri-

Suggested Citation:"Mexico." National Research Council. 1993. Sustainable Agriculture and the Environment in the Humid Tropics. Washington, DC: The National Academies Press. doi: 10.17226/1985.
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cultural enterprise and buffer the farmer against market fluctuations and failures of single crops.

Lessons from Development and Conservation Programs

Several different programs for small-scale producers on mostly nonirrigated lands were implemented in the past.

PLAN PUEBLA

The most important project of this type was Plan Puebla, which was initiated in 1967. The plan recommended the following components as part of a sustainable agricultural system: increased use of chemical fertilizers, timely application of fertilizers, and carefully determined densities of different races of maize. Plan Puebla provided credit and advice and was successful in improving maize productivity, which went from 1,330 kg/ha in 1967 to 3,000 kg/ha in 1981 (Volke Haller and Sepulveda-González, 1987).

An evaluation of this plan after 15 years, however, showed that the complete system was adopted by only 0.8 percent of the producers, and in turn, 0.6 percent decided not to follow any of the suggested techniques (González-Pacheco, 1983). Fifty-seven percent of the producers adopted only 30 to 70 percent of the techniques recommended by Plan Puebla.

It is important to examine the reasons producers had for not following the techniques recommended by Plan Puebla because they represent many of the points that need to be addressed in future recommendations for sustainable agricultural techniques. The principal ones mentioned by Volke Haller and Sepulveda-González (1987) are as follows:

  • Lack of knowledge of the new technology;

  • Greater economic risk from using the recommended technology;

  • Aversion to the credit needed to obtain the recommended technology and the paperwork needed to apply for credit;

  • Deficiencies in the insurance included with the loan (insurance usually does not pay in case of natural disasters);

  • Delays in fertilizer deliveries;

  • Competing opportunities for income outside the field of agriculture;

  • Small field sizes (the smaller the field, the lower the adoption of the technology); and

Suggested Citation:"Mexico." National Research Council. 1993. Sustainable Agriculture and the Environment in the Humid Tropics. Washington, DC: The National Academies Press. doi: 10.17226/1985.
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  • Other causes, such as the age, education, and family size of the producer and the complexity of the technology.

Gladwin (1976) stressed that the critical factors that limited the adoption of one recommendation of the program were not necessarily the critical factors that limited the adoption of other recommendations. For instance, fertilizer use was limited by credit ineligibility, whereas different planting techniques to increase plant populations were not adopted because of the lack of knowledge of the specific recommendations.

TROPICAL CHINAMPAS

Another case worth reviewing is the transfer of chinampa (agricultural production in raised fields surrounded by water) technology to the tropical lowlands of Tabasco and Veracruz during the 1970s. Although experience was gained from this project, the transfer was successful only in the pilot demonstration plots. The structure (raised fields) of the technology was transferred to the swamps of Tabasco (the Camellones Chontales project), but the agricultural component was not (Gómez-Pompa and Jiménez, 1989). This was mainly because the need to intensify agricultural activities was not identified by the farmers, the time required to maintain the system was much more than the time normally devoted to agricultural activities by local farmers, the lack of markets for the proposed products provided little incentive for its adoption, and no credit was available to the farmers.

One of the most important reasons that the majority of small-scale farmers gave for not adopting new technologies or new crops was frequently ignored: the uncertainty of the market. These farmers were aware of the experiences of other small-scale farmers who embarked on projects that left them in debt or with products they could not sell. Technologies that may improve the productivity of the fields without the risk of putting the farmer into debt would likely have more followers than would technologies that are capital intensive.

SECONDARY FORESTS OF VERACRUZ

Because most of the tropical rain forest in Mexico has disappeared, it is important to use and manage secondary forests so they may provide a wide range of agricultural products—from vegetables to timber. In situ experimental research on secondary forest has been

Suggested Citation:"Mexico." National Research Council. 1993. Sustainable Agriculture and the Environment in the Humid Tropics. Washington, DC: The National Academies Press. doi: 10.17226/1985.
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undertaken in Uxpanapa, Veracruz, where the secondary vegetation has been used as a substrate for newly introduced, valuable species (del Amo, 1991). A variety of agroforestry systems have been evaluated, including a diverse milpa and an enriched 11-year-old secondary forest (acahual). The project demonstrated that use of combinations of various types of crops and arrangements—in patches—of different systems like diversified milpa, orchard, and agroforestry are possible alternatives for the Veracruz region.

Tropical Forest Action Plan (PAFT)

Mexico has joined an international effort headed by FAO to develop a worldwide Tropical Forestry Action Plan. Several versions of an action plan for Mexico (Plan de Acción Forestal del Trópico [PAFT]) have been produced by the undersecretary of forestry of the Secretary of Agriculture and Hydraulic Resources of Mexico (Comisión Nacional Forestal, 1988). PAFT follows the same unsuccessful lines that Mexico has been using for some time: calling for the management of forest resources without specifying what type of management or what will ensure the plan' s continuation after the initial funding for development is gone.

The first draft of PAFT is discussed here because of the amount of effort and the resources that may be allocated to it. Several points of the first draft of the proposed action plan can be criticized:

  • PAFT recommends the establishment of forest plantations without specifying the species, areas, or techniques that should be used and, most important, without the participation of the private sector or local communities.

  • The conservation of genetic resources could be a significant contribution from PAFT, but the plan does not specify how this will be done or who will be responsible for protecting genetic resources.

  • There are no specifications for collaboration with the research institutions or nongovernmental organizations that made PAFT a reality.

  • The strengthening of education and research is a necessary and fundamental action, but the action plan provides no guidelines on how this will differ from the education and research elements of the present programs in agriculture, forestry, agroforestry, or resource management, which are inadequate.

  • No opportunities for independent research organizations have been created, even though several such organizations and institutions have ongoing tropical forest research projects.

Suggested Citation:"Mexico." National Research Council. 1993. Sustainable Agriculture and the Environment in the Humid Tropics. Washington, DC: The National Academies Press. doi: 10.17226/1985.
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  • PAFT proposes to undertake the inventories needed for planning, but there is no mention of the relationship of PAFT with other development plans in the agriculture, animal husbandry, or oil exploration sectors. The need for coordination and development of a land use system with enforced zoning is not discussed; yet, without this, the inventories are of little use except for monitoring deforestation.

  • The development of roads as a result of the recommendations of the action plan will only contribute to more deforestation—a common consequence of development programs.

  • The project includes the temperate pine-oak forests of the Sierra de Juárez (Oaxaca).

  • In the past, the treatment of “sick” forest stands, known as “forest health” activities (“sanidad” forestal) has received large financial expenditures, although there is little scientific basis for the forest health program. Inclusion of forest health in PAFT seems dubious.

  • The identification of rare and endangered plants and animals is of great importance, but PAFT does not indicate that this be will accomplished or what will be done with the information if identification is accomplished.

  • The restoration of lands deforested by shifting agriculture seems the most appealing project, but PAFT provides no information on how this will be accomplished or what role the shifting cultivators would have in the plan. The same applies to the management of secondary forests proposed by PAFT.

  • The establishment of pilot projects for the integral management of natural resources also has great potential and has been tried several times in the recent past. There is no information as to why these pilot projects should succeed while others have failed.

The Tropical Forest Action Program (PROAFT), a new tropical forest action plan, which will attempt to rectify these problems, is currently under way in Mexico.

Sustainable Food and Commodity Production

An ecologic approach to food and commodity production is important to the tropical environment in Mexico because it is essential to develop food production systems that depend less on inputs, particularly import inputs (for example, reliance on outside production). Many of the traditional cultural practices commonly used by local farmers may contain important ecologic attributes that contribute to sustainable agricultural yields. The problems that small-scale producers face, however, have made many traditional practices inappro-

Suggested Citation:"Mexico." National Research Council. 1993. Sustainable Agriculture and the Environment in the Humid Tropics. Washington, DC: The National Academies Press. doi: 10.17226/1985.
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priate for the sustained production to meet current market demands. Nevertheless, Gliessman et al. (1983) and Gómez-Pompa (1978) have provided good examples of how the strengths of traditional agricultural systems can be retained in a system that is modified to meet contemporary needs.

Sustainable food production can be tailored to fit each unique situation. A sustainable low input system with intensive hand labor may share a few characteristics with a high-input highly mechanized system in the same area with both having a limited impact on the environment. The hard labor-intensive system may rely on biological fertilizers (for example, organic matter and fallow) while the highly mechanized input system may rely on carefully placed chemical fertilizers with more limited use of organic fertilizer—yet, if each is done well, they may be equally sustainable, technically.

Agroforestry for Mexico

Despite recent advances in tropical forest ecology and forest management, deforestation continues virtually unabated. Reforestation efforts are insignificant and the area of humid tropical forest under management that will maintain productivity and profitability is growing slowly, if at all. Improving forest management is perhaps the best and only hope for saving and restoring the tropical forests of the Mexican humid tropics, maintaining the productivity of these often fragile lands, and improving the quality of life for the residents of those areas.

The loss of tropical forests in the Mexican humid tropics is more than an ecologic tragedy. Tropical forests play an important role in regional and global scales in ecologic and economic terms. Ecologically, tropical forests are a primary factor in the carbon dioxide balance in the atmosphere. Economically, they contain many species of economic importance (timber, fruits, nuts, gums, medicines, understory plants, birds, and animals). Thousands of yet undiscovered or unstudied species have potential economic value, including species with future value for genetic engineering.

For the humid tropics of Mexico and Central America, agroforestry is receiving attention as a method of resource management that efficiently uses resources and that is environmentally positive (Adelhelm and Kotshci, 1985; Alcorn, 1984, 1990; Gómez-Pompa, 1987a; Lagemann, 1982; Nations and Komer, 1983; Vergara and Briones, 1987), but it will take time to develop skilled agroforesters. There are few people adequately trained in this field to teach new practitioners and even with adequate support, it may take 10 years to provide a sufficient

Suggested Citation:"Mexico." National Research Council. 1993. Sustainable Agriculture and the Environment in the Humid Tropics. Washington, DC: The National Academies Press. doi: 10.17226/1985.
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number of practitioners and instructors to meet the demand. The rapid increase in interest and promotion of agroforestry has not yet been accompanied by well-funded interdisciplinary research to better understand how traditional agroforestry systems work, how to improve the methods of teaching agroforestry, and how to improve demonstration and development projects.

Agroforestry research is, by necessity, slow and complex (Cannell and Jackson, 1985). This makes the study of traditional agroforestry systems extremely valuable. The lessons that have been learned from successful and failed agroforestry systems are equally important.

The advantages and the potential of the complex, traditional types of forest management are clear for the humid tropics (Bene et al., 1977), but forest management has not been improved. Although numerous factors account for the disparity between the promise and reality of agroforestry, ignorance is the greatest problem (Bainbridge, 1987a). The complex forest management practices that must be used do not fall under either conventional forestry or agricultural systems. As a result, they were ignored until recently (see, for example, Winterbottom and Hazelwood [1987] and Shepherd and Stewart [1988]).

Most of the research in traditional forestry management in the humid tropics of Mexico has been done by anthropologists and ethnobotanists. The International Center for Research on Agroforestry (ICRAF) was established in 1977, but a comprehensive work program for the center was not developed until 1982 (Lundgren and Raintree, 1982), and the location of ICRAF (Nairobi, Kenya) has led to an emphasis on Africa. Work in other areas of the world, such as the humid tropics of Mexico, has been very limited.

Although the Centro Agronómico de Investigación y Enseñanza (CATIE) (Costa Rica) has been active and effective with limited resources, it has not been able to effectively contribute to the improvement of resource management in Mexico and other Latin American countries with tropical forests. It is most unfortunate that a comprehensive plan for preserving traditional knowledge and for developing education programs, demonstration plots, research programs, and data bases for the many ecosystems and cultures of the humid tropics of Mexico has not been developed.

In addition to the traditional methods of forest management in the Mexican humid tropics, there are many potentially valuable methods and crops from comparable humid tropical zones. One of the most promising of these combines strips of trees with agricultural crops (alley cropping). The most common trees for these alley cropping systems are fast-growing, multipurpose, nitrogen-fixing trees that, through root symbioses, make atmospheric nitrogen available to the

Suggested Citation:"Mexico." National Research Council. 1993. Sustainable Agriculture and the Environment in the Humid Tropics. Washington, DC: The National Academies Press. doi: 10.17226/1985.
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tree and, subsequently, to other plants and crops) (Torres, 1983; Wilson et al., 1986; Yamoah and Burleigh, 1990). These systems provide fuelwood, building materials, and fodder while they increase and maintain the productivity of the agricultural crops and provide other ecologic and environmental benefits including slope stabilization, erosion control, and habitat for wildlife (Ehui et al., 1990).

Sustainable Livestock Production

Because cattle ranching has been the most important cause of deforestation (Denevan, 1982; Myers, 1981; Shane, 1980), cattle production must be improved on lands where the forest has been removed. Sufficient work has been done to suggest some of the possibilities for sustainable livestock production in the humid tropics (Murgueitio, 1988, 1990; Preston and Leng, 1987). The rapid growth of fodder trees, including nitrogen-fixing species, makes it possible to improve cattle production with trees (Preston and Murgueitio, 1987). Unpublished work from researchers at the Postgraduate College of Chapingo in Veracruz indicate that aquatic plants and other nonconventional plants can be used as fodder for cattle. The Australians have adapted ruminant microflora to better utilize Leucaena spp. (Reid and Wilson, 1985).

Sustainable Management of Biodiversity

A sustainable approach for the conservation of biodiversity in tropical forests is to protect forests from human actions that threaten diversity. One alternative would be to use protected areas where the ecosystems are managed and used rather than just preserved.

PROTECTED AREAS AND BUFFER ZONES

Protected areas are not islands but, rather, areas within larger ecologic and social systems. Management of these areas requires continual adjustment to external social, political, and economic pressures; otherwise, they run the risk of being engulfed by unsustainable practices. This type of management could include the selective and careful extraction of valuable woods, prescribed burning of land, hunting, ecotourism, even forest restoration, provided that it is done in a manner that will enhance the ecosystem's sustainability. If local people are to protect these areas, they should be provided with jobs and benefits, whether directly through employment in management work (protection and restoration) or more indirectly (through tourism or

Suggested Citation:"Mexico." National Research Council. 1993. Sustainable Agriculture and the Environment in the Humid Tropics. Washington, DC: The National Academies Press. doi: 10.17226/1985.
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reserve support) and improved access to resources essential to survival (for example, fuelwood and food) (McNeely, 1988). Integrating the needs of these people into reserve management plans is not only challenging but also essential. Local people cannot, and should not, be expected to bear the cost of conservation.

PRESERVING BIODIVERSITY IN MANAGED AREAS

Other approaches to protecting plant biodiversity might include identifying new markets for rare landraces or traditional crop varieties, subsidies to farmers who cultivate important landraces, or support for more traditional methods of species protection in botanical gardens and gene banks (Altieri and Merrick, 1987). These alternatives might provide jobs and resources for a limited number of local people.

STRATEGIES FOR IMPROVING RESOURCE MANAGEMENT

Improvement of resource management systems to protect and restore the humid tropical forests will require a variety of strategies and programs involving policy, research, education, demonstration, and implementation. These strategies and policies offer the best hope for conserving the existing forests, improving management of the existing forests, promoting reforestation, and improving living conditions for the local people. If they are ignored, the forest area will decline, extraction of forest products from biologically and culturally rich areas will continue, invaluable species and traditional knowledge will be lost, and poverty levels among the local people will increase. As Janzen (1988:243) stated, “Restriction of conservation to the few remaining relatively intact habitat patches automatically excludes more than 90 percent of tropical humanity from its direct benefits; restoration is most needed where the people live.”

It is a mistake to continue to underestimate the skills and knowledge of the local people. In many cases they have managed the forests in a sustainable manner for hundreds of years. If Mexico fails to adopt an ecologic and cultural approach to sustainable resource management, funding and energy will be expended to protect forest areas with little hope for success. Present conservation management approaches continue to ignore the fact that the forests were, are, and will continue to be inhabited. A wiser approach is needed to protect the needs of both the environment and the people and should involve the local inhabitants in the protection and management of the environment.

Suggested Citation:"Mexico." National Research Council. 1993. Sustainable Agriculture and the Environment in the Humid Tropics. Washington, DC: The National Academies Press. doi: 10.17226/1985.
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Policy

The following are some suggestions related to policy issues for improving sustainable resource management in the Mexican humid tropics.

  • A Policy Prospectus Is Needed A policy statement that explicitly states the importance of sustainable management in resource planning for the humid tropics of Mexico is needed for the areas of agriculture, forestry, and associated land-use practices.

  • Incentives for Sustainable Land Use Are Needed Sustainable land management will develop only if it is profitable in economic and social terms and only if people receive a benefit from doing what is appropriate for long-term use (Carpenter, 1989; Murray, 1989). Research should include an evaluation of tax policies and possible incentives to promote long-term planning for sustainable agricultural practices, which often provide large profits over the long-term but low immediate returns. As Repetto (1990) observed, institutional factors often drive the system toward ecologic and economic disaster.

The results can be striking when local people are involved in the planning process and receive immediate benefits. For example, Haitians voluntarily planted more than 5 million trees on their own land in the first 2.5 years of a project that incorporated local people into the planning process (Murray, 1989). Success was attributed to more than just profitability. Project planners consciously tried to introduce trees that could be integrated into the farmers' existing cropping systems, which is important for ensuring the acceptance of any innovation (Evans, 1988). The rapid expansion of intercropping in China, from 20,000 ha intercropped with Paulownia trees in 1973 to more than 1.5 million ha in 1988, was made possible by an equally well-designed program (Zhaohua, 1988).

This effort should also include the development of incentives for the sustainable management of tropical forests. This is the best way to ensure the survival of large areas of forest. Methods and techniques are available; long-term commitments by government and private industry are needed.

  • Incentives to Conserve Biodiversity Are Needed Initiatives for conserving biodiversity and for small-scale farmers to use sustainable resource management practices should be developed and promoted. These incentives should include actions that improve the quality of life for people in the local communities.

Three-way alliances for conservation and sustainable agriculture could be established. In these alliances, the central party is the com-

Suggested Citation:"Mexico." National Research Council. 1993. Sustainable Agriculture and the Environment in the Humid Tropics. Washington, DC: The National Academies Press. doi: 10.17226/1985.
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munity or local people integrated with a second party consisting of a research organization (private or governmental). The third party would be a funding agency (governmental or nongovernmental) that would facilitate and support the activities. Through such an alliance, long-term agreements to protect small or large areas in small-scale farming communities could be established.

  • New Policies for Conserving Biodiversity Are Needed A working network of reserves based on the biologic importance of different areas needs to be established. Although most reserves have been placed where a large piece of less disturbed forest exists or an important archeological site or place of beauty can be found, the importance of the biodiversity of various regions has rarely been taken into account. Areas of special biodiversity must be identified and protected.

A new network of protected areas and protected agricultural systems needs to be developed to conserve important landraces of cultivated plants, especially plant material related to the major food crops: such as maize, cassava, and beans. The sustainability of future production may depend on this.

Ex situ genetic banks of valuable, rare landraces and other important crop relatives should be established.

Management plans for all existing reserves should be prepared. These should be designed to conserve the biodiversity, to favor its enrichment, to follow and guide natural changes, and to allow for experimentation.

In the conservation of biodiversity, incentives should be developed for the participation of the private sector and those who own large areas of land. One option is to use tax breaks. This may encourage the creation of small to large reserves in Mexico as well as provide financing. In addition, those who own large areas of land need to take responsibility for the potential effects of their own agriculture and ranching activities on the land they own and on the ecosystems that surround their land.

More attention and research needs to be focused on buffer zones (areas surrounding or adjacent to important protected areas). Well-managed buffer zones could provide models for the integration of conservation and sustainable land use practices to other regions of Mexico.

  • Institutional Barriers Need To Be Broken Studies of the humid tropical forests of Mexico should include a detailed review of institutional needs and limitations, so that projects can proceed with minimal interference and maximum support from government regulatory

Suggested Citation:"Mexico." National Research Council. 1993. Sustainable Agriculture and the Environment in the Humid Tropics. Washington, DC: The National Academies Press. doi: 10.17226/1985.
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and administrative programs (local to national scale). This review should include the needs and limitations of government departments, owners of large areas of land, and land managers. It should also take into account the market system for tropical forest products, from the producer to eventual retail outlet; the commercial sector, including alternatives to rain forest products; schools; religious groups; and the economic community (banks and lenders, etc.).

  • Local Land and Tree Tenure Considerations Need To Be Reviewed One of most important and sensitive issues in resource management is the insecurity of land tenure. Even if resource management systems protect the soil, conserve nutrients, and provide food and income, farmers have little or no motivation to invest in agricultural activities with long-term benefits unless there is some certainty of reaping the benefits (Fortmann, 1985). In some areas, tenants risk eviction if they improve the land they farm; if the land becomes too productive, the landlords may claim it and farm it themselves (for further information on tenure, see Fortmann and Bruce, 1988; Fortmann and Riddell, 1985; Labelle, 1987; Raintree, 1987a). The separate problems of security for the ejido, ejidatarios' households, and ejidal lands need to be examined to develop policies that are not contradictory and that are specific to the needs of people in different regions.

Research

Research is needed in many areas. The following are strategies for improving future research.

  • Traditional Knowledge Should Be Documented by Working with Local People and Communities Because it may prove to be difficult to match the ecologic and cultural adjustments achieved by traditional farmers after centuries of trial and error, the development of detailed data on traditional agroforestry systems is of paramount importance, especially since detailed knowledge of the local environment is vanishing along with the forests (Gómez-Pompa, 1987b; Gómez-Pompa and Bainbridge, 1991; Raintree, 1982; Raymond, 1990). This research should involve multidisciplinary teams and must include the people from the local communities involved. Multidisciplinary, mixed-gender teams of local students, faculty, and international collaborators are preferred for the development of detailed information on the full ecologic and cultural complexities of these systems. The decision-making processes of farmers should be an important part of this research. Gladwin (1976, 1979, 1983) has laid the groundwork for an appraisal of why farmers and foresters plant and harvest specific crops and why they do or do not accept recommended changes.

Suggested Citation:"Mexico." National Research Council. 1993. Sustainable Agriculture and the Environment in the Humid Tropics. Washington, DC: The National Academies Press. doi: 10.17226/1985.
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The need to include indigenous peoples in research and development programs has been emphasized in numerous case studies and reports on the process of development (Richards, 1985). The lack of this kind of input places in question the sustainability of any introduced change, despite the best intentions of those involved in development (Chambers, 1987). Although it is often assumed that people will accept an innovation because “it is good for them,” to succeed, a program must meet the real and perceived needs of the people involved and fit the social and cultural setting (Leeger, 1989). Research done in collaboration with local people provides the groundwork for successful development and demonstration projects.

The successes and the failures of traditional agricultural systems must be evaluated. The objective is to understand the ability of a given agroecosystem to meet environmental and sociocultural needs in a given region. The integration of experienced folk knowledge with conventional scientific knowledge of agricultural, silvicultural, and cattle production systems can serve as a powerful base for designing improved agroecosystems and assessing the potential for technology transfer.

  • Research Incentives that Include Basic and Applied Management Considerations, Farmer-to-Farmer Exchanges, and Farmer-Managed Research Should Be Developed The case study approach is one of the best ways to teach agroforestry and to encourage agroforestry research (Bainbridge, 1990a,b; Huxley, 1987). In academic settings, the system for meritorious recognition should be restructured to ensure that research solutions for real-world problems are given at least as much consideration as peer-reviewed journal articles. The role of farmers in this work must be expanded because farmers are often excellent teachers and extension workers (Gómez-Pompa and Jiménez-Osornio, 1989; Springborg, 1986) and are often better able to discuss issues and give demonstrations than are extension agents and researchers.

  • Support for Long-Term Research Should Be Increased The short-term nature of most research programs discourages and impedes agroforestry research. Typical funding cycles of 1, 3, or (more rarely) 5 years are incompatible with agroforestry research projects that may take 10, 20, 50, or more years. The importance of long-term funding has been recognized in only a few programs, most notably the Long-Term Ecological Research Program of the National Science Foundation (Callahan, 1984).

  • Support for Long-Term Monitoring Should Be Provided It is difficult to plan a research program without accurate information of current and past land use and environmental trends. The monitoring of

Suggested Citation:"Mexico." National Research Council. 1993. Sustainable Agriculture and the Environment in the Humid Tropics. Washington, DC: The National Academies Press. doi: 10.17226/1985.
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the social, economic, and ecologic variables that are thought to contribute to the deforestation process is needed. The human component in environmental monitoring is often forgotten, even though social and ecologic factors are obviously mutually driven and intertwined. This implies that not only inventories of flora, fauna, soils, and air quality be collected over time but also corresponding temporal data on human population and distribution, land use, and market patterns for economically valuable natural resources be collected as well. It requires accounting for environmental subsidies (for example, soil erosion and declining soil fertility). The information could be integrated and computerized in a geographic information system data base that could be used as a basis for future planning and recommendations.

  • A Regional Data Base of Multipurpose Tree Species Should Be Developed Creation of a regional data base of tree species, particularly multipurpose trees, deserves special priority. Multipurpose trees are of particular value in sustainable resource management for both subsistence and market production activities (Bainbridge, 1987b; Von Carlowitz, 1984). For example, the bread nut tree (Brosimum alicastrum) is a widespread species with multiple uses (food, fodder, and fuel) in the humid tropics of Mexico. It is thought to have been a vital food resource of the ancient Maya (Puleston, 1982) and may again return to prominence as a vital part of sustainable agricultural systems for the humid tropics (Pardo-Tejeda and Sánchez-Muñoz, 1980).

  • A Regional Data Base of Nitrogen-Fixing Tree Species Should Be Developed A data base of nitrogen-fixing trees, which are effectively used in traditional agroforestry systems and of special value in maintaining fertility and restoring degraded lands needs to be developed (Flores Guido, 1987; Ngambeki, 1985; Virginia, 1986).

  • A Regional Network of Resource Research Groups and Institutions Should Be Established A regional network of research groups and institutions modeled after the regional cooperative research and food production program known as Precodepa (Regional Cooperative Potato Program [see Niederhauser and Villarreal, 1986]) should be established. Precodepa 's emphasis has been on building national research capabilities to provide a regional base of specialization and to transfer technology along with distributing shared information. This has enabled each participating country to take control of the program in their country and take pride in the achievements. Precopeda has been effective in maximizing the benefits gained from the limited funding for potato research. Funds are competitively allocated regionally, allowing specialization in various aspects of potato produc-

Suggested Citation:"Mexico." National Research Council. 1993. Sustainable Agriculture and the Environment in the Humid Tropics. Washington, DC: The National Academies Press. doi: 10.17226/1985.
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tion and utilization in different countries along with excellent distribution of shared information.

Forest management and information also need to cross over sociopolitical boundaries. Regional networking increases the effectiveness of research and allows more information and progress to be obtained from the limited funding available (Piñeiro et al., 1987). Inclusion of nongovernmental organizations is of special importance because their contributions to solutions to the problems of deforestation and sustainable resource management have proportionally been far greater than the funding they receive.

Education

The following are strategies for improving education in sustainable resource management.

  • Local Farmers Should Be Included as Teachers in Educational Efforts The knowledge and wisdom of local farmers need to be included in educational curricula and resource management studies (Gómez-Pompa and Kaus, 1992). This knowledge has been ignored by experts, and this has been a persistent problem in both agriculture and forestry research and extension (Bainbridge, 1987a).

  • Educational Programs that Encompass the Full Range of Resource Management Issues and Address Integrated Resource Management Should Be Developed Schools of agriculture, veterinary medicine, human medicine, anthropology, biology, engineering, and economics should be involved in and include resource management issues.

Agroforestry systems, which are not part of conventional forestry or agricultural systems, are often considered primitive and have been ignored. Instead, intensive high-input systems have been emphasized despite their repeated failures. In many cases, these high-input systems perform poorly while local people continue to survive with long-established (but unstudied) agroforestry systems with native trees.

The educational systems of the United States and Mexico have emphasized a narrow vision of forestry that prepares students for intensive industrial production of monocultures (for example, pine and eucalyptus trees) but that ignores agroforestry applications (Bainbridge, 1987a). In the index of the major North American forestry journal, the Journal of Forestry, for example, there was not a single listing for agroforestry in 1990. Most agroforesters have remedied the failures of the United States and Mexican educational systems by working with farmers who use traditional agricultural sys-

Suggested Citation:"Mexico." National Research Council. 1993. Sustainable Agriculture and the Environment in the Humid Tropics. Washington, DC: The National Academies Press. doi: 10.17226/1985.
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tems—a necessary step but one that could be much more valuable with appropriate training in the classroom.

The educational systems in both the United States and Mexico must be revised to introduce the complexity and interaction of ecologic and cultural systems (Bainbridge, 1985, 1990b; Bawden et al., 1984; Chowdry, 1984). This has become much easier with the development of educational materials at ICRAF (for example, see Zulberti, 1987) and CATIE (Major et al., 1985), but there is still a shortage of material in Spanish. There is little or no information in the Maya language or in a pictorial format suitable for use by the people, many of whom are illiterate, who are expected to do the hands-on work or adopt the proposed forestry or agricultural programs. In addition, most of the education represents urban perceptions of the environment and neglects rural knowledge, experience, needs, and aspirations (Gómez-Pompa and Kaus, 1990).

  • Information About Different Approaches for Sustainable Resource Management in the Tropics, from Shifting Agriculture to Grain-Fed Cattle Ranging, Needs to Be Disseminated The public needs to understand that virtually all food and natural resource production practices can be sustainable if the correct approach is used. Pollution is not necessarily a synonym for modern agriculture, and traditional agriculture is not a synonym for low productivity. The conventional myths of agriculture, forestry, and conservation need to be dispelled before public pressure will lead to policies and practices that are appropriate to the realities of working and caring for the land.

Demonstration Projects

The following are suggestions for demonstration projects of sustainable resource management in the Mexican humid tropics.

  • Demonstration Projects Need to Be Developed in Local Communities Demonstration projects should be one of the first priorities for future funding. There is no shortage of potential sites, but there is a lack of trained personnel. Demonstration projects can provide much needed training in project management. Janzen's effort to reforest the Guanacaste National Park in Costa Rica (Murphy, 1987) is a worthy model. Many projects with scopes and visions similar to those of Janzen's project are needed in the humid tropics of Mexico.

By necessity, the development and testing of agroforestry systems for the humid tropics of Mexico must begin before all the desired information on tree species and traditional agroforestry prac-

Suggested Citation:"Mexico." National Research Council. 1993. Sustainable Agriculture and the Environment in the Humid Tropics. Washington, DC: The National Academies Press. doi: 10.17226/1985.
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tices is available. Fortunately, as has been learned in ecologic studies, it is possible to make advances without a complete understanding of each component of the agroecosystem. Agroforestry development and implementation are rarely simple, and new tools may have to be developed to properly consider the complex ecologic and social factors involved (Raintree, 1982, 1987b).

  • Natural Forest Management Projects Should Be Developed There are no large areas of managed tropical forests in Mexico. Although the management of natural forests is an important alternative that has been neglected in most tropical areas (Gómez-Pompa and Burley, 1991), there are methods for doing it (Schmidt, 1991). These methods could be demonstrated on small private and government-owned forests.

  • Plantation Designs Should Be Improved and Tested The establishment of tree plantations by private groups is also suggested to meet the demand for wood products. Research in this area is also of great importance. Trees are as challenging to grow as other agricultural crops and merit long-term research efforts to improve tree production and marketing and protection of trees from pests and diseases.

  • Restoration Reserves Should Be Established Experimental reserves for the restoration of biodiversity are needed (Bainbridge, 1990b) as are research and information on the restoration of degraded or impoverished tropical ecosystems. The degraded ecosystems are predominant, yet they hold great potential for the future. Restoration reserves should include sound agricultural, silvicultural, and animal husbandry activities that are compatible with sustained use of the area's resources. This research is challenging and the magnitude of the task should not be underemphasized. Although it is not possible to state that the full complex community of the humid tropical rain forest can be restored, many important species and functions of the forest can be reestablished in areas that are now degraded and very unproductive.

Implementation of Sustainable Resource Management

High priority should be given to the ejido (peasant) sector of the Mexican population. These rural populations may better understand new sustainable approaches of resource management because of their firsthand experience with similar, traditional agricultural practices. This should include education, extension activities, financing, marketing, and in particular, in-situ research. It is strongly suggested

Suggested Citation:"Mexico." National Research Council. 1993. Sustainable Agriculture and the Environment in the Humid Tropics. Washington, DC: The National Academies Press. doi: 10.17226/1985.
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that any activity in this sector involve local people because without their participation the program is bound to fail. Use of the alliance approach outlined above for the conservation of biodiversity would also be a good strategy. This calls for a new green revolution of small-scale agricultural landholders. The rewards could be extraordinary.

The following are suggestions for implementing sustainable resource management.

  • Development-Oriented Projects with Local People Should Be Developed In addition to demonstration projects done on a local level, larger development-oriented projects for the protection and restoration of humid tropics must also be established. Experience has demonstrated that expert recommendations for development are often of little value to local people because the recommendations commonly reflect the goals of the experts, not the local people whose needs are complex and who are adverse to risk (Edwards, 1989). It is essential to determine what people are doing and using, what they need and want, and why (Gómez-Pompa and Bainbridge, 1991; Gómez-Pompa and Jiménez-Osornio, 1989; Jecquire, 1976; Raintree, 1987b; Retiere, 1988). Improved tropical forestry management cannot be imposed from above or abroad. It must be developed by working with local communities and people.

  • Participation of Women in Education, Research, Extension, and Development Should Be Increased The role of women is important and should not be ignored or neglected (Charlton, 1984; Fortmann and Rocheleau, 1985; Rocheleau, 1988). In some countries, more than half of the agricultural labor force is composed of women and from 40 to 80 percent of agricultural products are produced by women (Boulding, 1977; Howell, 1978). There are few data on the contributions of women to resource management in Mexico. It is known that women are very active in food production (commonly in the homegarden), in raising small livestock and poultry, and in gathering fuelwood. Their importance is greater than these data imply, however.

  • Rural Appraisal or Evaluation Forms Should Be Developed and Survey Materials Should Be Made Available to Researchers, Educators, and Communities so that They Can Understand Existing Practices and Land Use Allocations and Develop More Sustainable Management Packages The AFRENA (Agroforestry Research Network for Africa) survey (Scherr, 1987) is a useful starting point for development projects, but it should be augmented with more detailed ethnobotanical, ecologic, and cultural surveys.

Suggested Citation:"Mexico." National Research Council. 1993. Sustainable Agriculture and the Environment in the Humid Tropics. Washington, DC: The National Academies Press. doi: 10.17226/1985.
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Farmers are “inventive, but development agencies rarely harness this inventiveness because they misunderstand the nature of both the agriculture and the politics of communities where food production is a major interest ” (Richards, 1985:192). Intimate knowledge of a community and its culture is a prerequisite to any work that is intended to aid that community (de Wilde, 1967). To be successful the project must meet local needs, fit the local environment, and provide sufficient benefits so that action will be taken (Murray, 1989). If these requirements are met, the techniques will spread.

  • A Program to Help Local Communities Plan and Implement Appropriate Development Programs Should Be Developed Working with local people, information on planning and implementing appropriate development programs could then be used to develop a set of management goals and objectives. These would include economic (cash crops), subsistence (food, fodder, medicine), and environmental objectives. Planning should include long-term (10-, 20-, 50-, 100-year) objectives and project future demands based on population growth (Gómez-Pompa and Bainbridge, 1991). To reduce the risk from such activities, emphasis should be given to native species and, preferably, local ecotypes in mixed stands rather than monocultures. Ecologic succession can be used to reduce the cost and uncertainty of establishing a program in harsh and difficult environments (Khoshoo, 1987).

  • Innovative Investment Programs Should Be Developed Access to credit or capital is often the factor that limits improvements in resource utilization. Loans or small grants (less than US$200) may be catalysts for change, as the innovative small-loan program of the Grameen Bank in Bangladesh has shown (Yunus, 1990). Targeting investments to remove infrastructural constraints (for example, transport and storage problems) may be more important than making investments at the farm level. One way to stimulate diversified activities is to connect campesinos with markets (Brannon and Baklanoff, 1987) or to help develop local markets.

Plan for Success

If sustainable agriculture options are successfully implemented (as they can be), secondary problems may arise. For example, if farmers are successful, they may build up their equity and begin efforts to increase the size of their farms. If this demand for new lands is not met by converting existing grazing lands, it will put additional pressure on the few remaining forested lands and on farmland operated by less productive farmers. It will be important to develop

Suggested Citation:"Mexico." National Research Council. 1993. Sustainable Agriculture and the Environment in the Humid Tropics. Washington, DC: The National Academies Press. doi: 10.17226/1985.
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and implement policies carefully to restrict the use of forested lands for agricultural expansion and to establish policies that will encourage the use of grazing lands for agriculture. Cattle production can easily be accommodated by using more efficient cattle feeding methods (Caesar, 1990; Preston, 1990).

Another possible consequence of a successful transition to sustainable resource management may be more efficient systems that require less hand labor, therefore providing more opportunities for the family to find other jobs in more urban areas. This trend may need to be addressed by government policies that will improve opportunities for displaced farmers or their children to obtain education or jobs or both in towns and cities. Many of these jobs may be provided by new processing and manufacturing facilities that use new forest products.

SUMMARY

These are the priorities for reversing current trends of deforestation and the use of unsustainable agricultural practices in the Mexican humid tropics. They are many and complex, and there is no single answer to the deforestation problem.

The best solutions are with small-scale farmers who have the experience, know the terrain, and have the most to gain. The responsibility of the nonrural sector—researchers, educators, industry, funding agencies, governments, and policy makers—lies in developing the infrastructure necessary to solve the problems. This will include better information, education, research, technological assistance, and credit incentives that help farmers build equity. The rural sector cannot respond to opportunities in the market without the means to adjust their production levels in terms of equipment, labor, market access, and knowledge. Investment in small-scale farmers at this very basic level, coupled with preparation for the consequences, can bring deforestation into check and can make agricultural practices in the Mexican humid tropics sustainable.

ACKNOWLEDGMENTS

The authors thank Silvia del Amo, Marlene de la Cruz, José Gonzalez, Steve Mitchell, Edward O. Plummer, and William W. Wood, Jr., for comments and suggestions on the first draft of this report. Reports from research undertaken under the Maya Sustainability Project (which is sponsored by the MacArthur Foundation) were used to supplement the available literature.

Suggested Citation:"Mexico." National Research Council. 1993. Sustainable Agriculture and the Environment in the Humid Tropics. Washington, DC: The National Academies Press. doi: 10.17226/1985.
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Sustainable Agriculture and the Environment in the Humid Tropics Get This Book
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Rain forests are rapidly being cleared in the humid tropics to keep pace with food demands, economic needs, and population growth. Without proper management, these forests and other natural resources will be seriously depleted within the next 50 years.

Sustainable Agriculture and the Environment in the Humid Tropics provides critically needed direction for developing strategies that both mitigate land degradation, deforestation, and biological resource losses and help the economic status of tropical countries through promotion of sustainable agricultural practices. The book includes

  • A practical discussion of 12 major land use options for boosting food production and enhancing local economies while protecting the natural resource base.
  • Recommendations for developing technologies needed for sustainable agriculture.
  • A strategy for changing policies that discourage conserving and managing natural resources and biodiversity.
  • Detailed reports on agriculture and deforestation in seven tropical countries.
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