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.



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Sustainable Agriculture and the Environment in the HUMID TROPICS 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.

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Sustainable Agriculture and the Environment in the HUMID TROPICS 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

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Sustainable Agriculture and the Environment in the HUMID TROPICS 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

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Sustainable Agriculture and the Environment in the HUMID TROPICS 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

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Sustainable Agriculture and the Environment in the HUMID TROPICS 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

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Sustainable Agriculture and the Environment in the HUMID TROPICS 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.

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Sustainable Agriculture and the Environment in the HUMID TROPICS 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

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Sustainable Agriculture and the Environment in the HUMID TROPICS 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

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Sustainable Agriculture and the Environment in the HUMID TROPICS 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

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Sustainable Agriculture and the Environment in the HUMID TROPICS 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.

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Sustainable Agriculture and the Environment in the HUMID TROPICS 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,

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