Below are the first 10 and last 10 pages of uncorrected machine-read text (when available) of this chapter, followed by the top 30 algorithmically extracted key phrases from the chapter as a whole.
Intended to provide our own search engines and external engines with highly rich, chapter-representative searchable text on the opening pages of each chapter. Because it is UNCORRECTED material, please consider the following text as a useful but insufficient proxy for the authoritative book pages.
Do not use for reproduction, copying, pasting, or reading; exclusively for search engines.
OCR for page 21
Soil and Water Quality: An Agenda for Agriculture 1 Soil and Water Quality: New Problems, New Solutions Since 1970, agricultural policymakers have been confronted with a new and vexing set of problems. Water quality problems resulting from the presence of nutrients, pesticides, salts, and trace elements have been added to an historical concern for soil erosion and sedimentation. Economic problems in the 1980s intensified concern about the loss of family farms and rural development issues. Maintaining the ability of U.S. agriculture to compete in international markets became a central tenet of agricultural policy, and agriculture became a central issue in international trade talks (e.g., General Agreement on Tariffs and Trade). At the same time profound structural changes were occurring in the agricultural sector and new technologies were changing the face of agricultural production. The search for solutions to these different but related problems has dominated debate over agricultural policy. SOIL AND WATER QUALITY PROBLEMS Soil and water quality problems caused by agricultural production practices are receiving increased national attention and are now perceived by society as environmental problems comparable to other national environmental problems such as air quality and the release of toxic pollutants from industrial sources. Severe soil degradation from erosion, compaction, or salinization can destroy the productive capacity of the soil and exacerbate water pollution from sediment and agricultural chemicals. Sediments from eroded croplands
OCR for page 22
Soil and Water Quality: An Agenda for Agriculture interfere with the use of waterbodies for transportation; threaten investments made in dams, locks, reservoirs, and other developments; and degrade aquatic ecosystems. Nutrients accelerate the rate of eutrophication of lakes, streams, and estuaries; and nitrogen in the form of nitrates can cause health problems if ingested by humans in drinking water. Pesticides in drinking water can become a human health concern and have been suggested to disrupt aquatic ecosystems. Salts can be toxic at high enough levels and can seriously reduce the uses to which water can be put. In some areas, toxic trace elements in irrigation drainage water have caused serious damage to fish, wildlife, and aquatic ecosystems. Soil Quality Renewed concern about soil erosion led to major new initiatives in the 1985 Food Security Act (PL 99-198; also known as the 1985 farm bill) (Table 1-1). For the first time, to be eligible for farm program benefits, agricultural producers were required to implement a soil conservation plan for their highly erodible croplands. A conservation plan was required for highly erodible land converted to cropland, and Congress also established the Conservation Reserve Program to pay producers to take highly erodible land out of production. Sheet and rill erosion remains an important problem, causing soil degradation on about 25 percent of U.S. croplands (Figure 1-1). Other forms of erosion—such as wind, gully, and ephemeral gully erosion—are also important and, if quantified, would expand the reported area of cropland on which erosion causes soil degradation. Conservation Compliance and Sodbuster, which are provisions of the 1985 Food Security Act, should result in substantial reductions in erosion caused by both wind and water. If these provisions are fully implemented and if the conservation practices remain in place, the United States will have taken a large step toward solving a soil erosion problem that has plagued U.S. agriculture since settlement by Europeans began. Even as major strides toward erosion control are being taken, however, new concerns about the soil resource are emerging. Compaction is increasingly noted as a factor that degrades soils and reduces crop yields, but no comprehensive data on the extent or severity of compaction are available. Salinization of soils, particularly in the western part of the United States, is causing serious and often irreversible damage where it is occurring (Table 1-2 and Figure 1-2). Investigators are also concerned about more subtle forms of soil degradation, such as declining levels of organic matter in the soil and
OCR for page 23
Soil and Water Quality: An Agenda for Agriculture TABLE 1-1 U.S. Department of Agriculture and U.S. Environmental Protection Agency Soil and Water Quality Programs Program Description U.S. Department of Agriculture Programs Conservation Reserve Program Provides annual rental payments to landowners and operators who voluntarily retire highly erodible and other environmentally critical lands from crop production for 10 years. Conservation Compliance Program Requires that producers who produce agricultural commodities on highly erodible cropland implement approved erosion control plans by January 1, 1995, or lose eligibility for USDA agricultural program benefits. Sodbuster Program Requires that producers who convert highly erodible land to cropland for the production of agricultural commodities do so under an approved erosion control plan or forfeit eligibility for USDA agricultural program benefits. Swampbuster Program Bars producers who convert wetlands to agricultural commodity production from eligibility for USDA agricultural program benefits, unless USDA determines that conversion would have only a minimal effect on wetland hydrology and biology. Agricultural Conservation Program Provides financial assistance to farmers for implementing approved soil and water conservation and pollution abatement practices. Conservation Technical Assistance Provides technical assistance by the Soil Conservation Service through county Conservation Districts to producers for planning and implementing soil and water conservation and water quality improvement practices. Great Plains Conservation Program Provides technical and financial assistance in Great Plains states to producers who implement total conservation treatment of their entire farm or ranch operation. Small Watershed Program Provides technical and financial assistance to local organizations for flood prevention, watershed protection, or water management. Resource Conservation and Development Program Assists multicounty areas in enhancing conservation and water quality, wildlife habitat and recreation, and rural development. Rural Clean Water Program An experimental program that ends in 1995 that provides cost-sharing and technical assistance to producers who voluntarily implement best-management practices to improve water quality. Extension Provides information and recommendations on soil and water quality practices to landowners and operators, in cooperation with the Soil Conservation Service and county Conservation Districts.
OCR for page 24
Soil and Water Quality: An Agenda for Agriculture Program Description Water Bank Program Provides annual rental payments for preserving wetlands in important migratory waterfowl nesting, breeding, or feeding areas. U.S. Environmental Protection Agency Programs Nonpoint Source Pollution Control Program Requires states and territories to file assessment reports with EPA identifying navigable waters where water quality standards cannot be attained or maintained without reducing nonpoint source pollution. States must also file management plans with EPA identifying steps that will be taken to reduce nonpoint source pollution in those waters identified in the state assessment reports. Grants are available to states with approved management plans to help implement nonpoint source pollution control programs. National Estuary Program Provides for identification of nationally significant estuaries threatened by pollution, preparation of conservation and management plans, and federal grants to prepare the plans. Clean Lakes Program Requires states to submit assessment reports on the status and trends of lake water quality, including the nature and extent of pollution loading from point and nonpoint sources, and methods of pollution control to restore lake water quality. Financial assistance is provided to states to prepare assessment reports and to implement watershed improvements and lake restoration activities. Regional Water Quality Programs Provides for cooperation between EPA and other federal agencies to reduce nonpoint source pollution in specified regional areas such as the Chesapeake Bay Program, the Colorado River Salinity Control Program, the Gulf of Mexico Program, and the Land and Water 201 Program in the Tennessee Valley region. Wellhead Protection Program Requires each state to prepare and submit to EPA a plan to protect from pollution, including from agricultural sources, the water recharge areas (areas where water leaching below the land surface replenishes the groundwater supplies tapped by wells) of wells that supply public drinking water. Coastal Zone Program Requires the implementation of enforceable management measures to protect coastal zones from nonpoint source pollution. SOURCE: Adapted from U.S. Department of Agriculture, Economic Research Service. 1989. Conservation and water quality. Pp. 21-35 in Agricultural Resources: Cropland, Water, and Conservation Situation and Outlook. Report No. AR-16. Washington, D.C.: U.S. Department of Agriculture.
OCR for page 25
Soil and Water Quality: An Agenda for Agriculture FIGURE 1-1 Percentage of land eroding by sheet and rill erosion at greater than the soil loss tolerance level. Minor land includes farmsteads, strip mines, quarries, gravel pits, borrow pits, permanent snow and ice, small built up areas, and all other land uses that do not fit into any other category. Source: Derived from U.S. Department of Agriculture, Soil Conservation Service. 1989. Summary Report: 1987 National Resources Inventory. Statistical Bulletin No. 790. Washington, D.C.: U.S. Department of Agriculture. the attendant degradation of soil structure, the soil's water-holding and nutrient-holding capacities, and biological activity (Larson and Pierce, 1991). The effect of soil degradation on carbon dioxide emissions is also receiving greater attention (Lal and Pierce, 1991). Water Quality Even as the 1985 Food Security Act was being debated, policymakers began to recognize that the intensification of agricultural production that gained speed in the 1970s was leading to a new set of environmental problems. Clark and colleagues (1985), for example, reported that sediments in U.S. waterways caused $2.2 billion in damage every year.
OCR for page 26
Soil and Water Quality: An Agenda for Agriculture TABLE 1-2 Cropland and Pastureland Soils Affected by Saline or Sodic Conditions Thousands of Hectares Region Total Affected Soils Total Cropland or Pastureland Percent Affected Northeast 0 10,562 <1 Appalachia 1 16,681 <1 Southeast 12 12,348 <1 Lake States 1,118 21,797 5 Corn Belt 158 47,623 <1 Delta 328 13,796 2 Northern Plains 8,110 41,198 20 Southern Plains 2,000 27,973 7 Mountain 6,075 20,516 30 Pacific 1,821 11,085 16 Other 6 1,082 <1 Total 19,630 224,659 9 NOTE: ''Other" refers to Hawaii and the Caribbean region. SOURCE: Adapted from U.S. Department of Agriculture, Soil Conservation Service. 1989. The Second RCA Appraisal: Soil, Water, and Related Resources on Nonfederal Land in the United States. Washington, D.C.: U.S. Department of Agriculture. Nitrates, pesticides, salts, and trace elements were increasingly reported in the nation's lakes, rivers, and groundwater bodies. These new concerns for the broader environmental effects of agricultural production led to increased attention to agriculture as a source of nonpoint source pollution problems in the 1987 amendments to the Federal Water Pollution Control Act (PL 100-4) and the 1990 Coastal Zone Act Reauthorization Amendments (PL 101-508), as well as to new initiatives in the 1990 Food, Agriculture, Conservation and Trade Act (PL 101-624; also known as the 1990 farm bill) (Tables 1-1 and 1-3). Surface Water Quality Agricultural production has been identified as a major source of nonpoint source pollution in U.S. lakes and rivers that do not meet water quality goals (Figure 1-3). Nutrients (nitrogen and phosphorus) and sediments, major pollutants closely associated with agricultural production, affect surface water quality in the United States (Figure 1-3) and loadings of these pollutants have increased in agricultural watersheds (R.A. Smith et al., 1987). Pesticides have also been reported in surface waters, often at high concentrations in the spring following pesticide application to
OCR for page 27
Soil and Water Quality: An Agenda for Agriculture FIGURE 1-2 Farm production regions used in this report. Alaska and Hawaii are included in the Pacific region. crops (Baker, 1985; Thurman et al., 1991), although the mean annual concentrations were low. The total loadings of nutrients and pesticides into estuaries such as the Chesapeake Bay have become serious problems (U.S. Environmental Protection Agency, 1990a). In the western United States, the pollution of surface waters with salts in waters drained from irrigated agricultural lands has become both a national and an international problem (National Research Council, 1989a). The long-standing concern about salt damage from irrigated agriculture has now been augmented with concerns about the delivery of toxic trace elements such as selenium (National Research Council, 1989a). Groundwater Quality Agricultural chemicals are also being detected in groundwater bodies. Nitrates have been widely reported in both shallow and deep aquifers, although rarely at levels exceeding health standards (Holden et al., 1992; Power and Schepers, 1989; U.S. Environmental Protection Agency, 1988, 1990b). Pesticides have been found less frequently and at much lower levels than nitrates, usually at concentrations below human health standards (Holden et al., 1992; U.S. Environmental Protection Agency, 1990b), although pesticides have been found at greater concentrations in surficial aquifers (Hallberg, 1989a).
OCR for page 28
Soil and Water Quality: An Agenda for Agriculture TABLE 1-3 New Initiatives in the 1990 Food, Agriculture, Conservation and Trade Act Initiative Description Conservation Compliance, Sodbuster, and Swampbuster Programs Potential penalties for violating provisions of these programs increased to include loss of eligibility for Agricultural Conservation Program, Emergency Conservation Program, Conservation Reserve Program, Agricultural Water Quality Protection Program, Environmental Easement Program, and assistance under the Small Watersheds Program. USDA is given more flexibility in assessing penalties. Conservation Reserve Program Provides for the extension of enrollment of land into the Conservation Reserve Program until 1995 and establishes priority areas for the enrollment of lands in Chesapeake Bay, Great Lakes, and Long Island Sound regions. Wetland Reserve Program Creates a new Wetland Reserve Program to offer long-term easements to producers who restore wetlands or who protect riparian corridors and critical wildlife habitats. Agricultural Water Quality Protection Program Provides for annual incentive payments to producers who implement a USDA-approved water quality protection plan. Incentive payments are for 3 to 5 years in duration and require the producer to keep records of the inputs used, yields achieved, and results of well water tests, soil tests, or other tests for each year in which incentive payments are received. Environmental Easement Program Provides for long-term protection of environmentally sensitive lands or to reduce water pollution by offering long-term or permanent easements to producers who retire lands already enrolled in the Conservation Reserve Program, in the Water Bank Program, or lands in riparian areas, critical wildlife habitats, or other environmentally sensitive areas that, if cropped, would prevent a producer from complying with state of federal environmental goals. SOURCE: U.S. Department of Agriculture, Economic Research Service, Resources and Technology Division. 1991. Conservation and water quality. Pp. 23-41 in Agricultural Resources: Cropland, Water, and Conservation Situation and Outlook. Report No. AR-23. Washington, D.C.: U.S. Department of Agriculture.
OCR for page 29
Soil and Water Quality: An Agenda for Agriculture FIGURE 1-3 Sources and types of nonpoint source pollution in affected U.S. rivers and lakes. Source: A. E. Carey. 1991. Agriculture, agricultural chemicals, and water quality. Pp. 78-85 in Agriculture and the Environment: The 1991 Yearbook of Agriculture. Washington, D.C.: U.S. Government Printing Office.
OCR for page 30
Soil and Water Quality: An Agenda for Agriculture Environmental Risks The damage to agricultural productivity caused by soil degradation and the effects of drinking water contaminated with nitrates, pesticides, salts, or trace elements on human health have, to date, been the driving forces behind the increased concerns over soil and water quality. More recently, however, the pervasive effects of human activities, particularly agricultural activities, on ecosystems and the ecological risks of these activities have received more attention. The effects of sediment, pesticide, nutrient, salt, and trace element loads on aquatic ecosystems may, in the long-term, prove to be more important than their potential effects on human health. In surface water and groundwater, levels of these pollutants that are below human health standards may still be high enough to damage ecosystems. Assessment of the ecological risks of soil and water quality degradation may increasingly become the yardstick used to measure the damage caused by soil and water quality degradation (U.S. Environmental Protection Agency, Science Advisory Board, 1990). SEARCH FOR SOLUTIONS The expansion of environmental issues on the agricultural agenda has led to calls for a reassessment of agricultural production practices and for the development of sustainable production systems that are environmentally sound as well as profitable (Harwood, 1990; Madigan, 1991; National Research Council, 1989b). Development of policies and programs that can be used to change agricultural production practices, however, has not proved easy. Factors Influencing Solutions Each year U.S. food and fiber producers make millions of individual decisions that ultimately affect soil and water quality. Producers do not, however, make these decisions in a vacuum. They are influenced by their personal situations, the quantity and quality of the resources and technologies to which they have access, market prices, agricultural policies, environmental regulations, the use rights producers hold for the resources on their property, and the recommendations producers receive from public- and private-sector experts. Figure 1-4 shows how the market environment, agricultural policies, environmental regulations, and private- and public-sector recommendations influence producers' decisions (Creason and Runge, 1990).
OCR for page 31
Soil and Water Quality: An Agenda for Agriculture Figure 1-4 Interactions of factors that influence producers' decisions. Source: J. R. Creason and C. F. Runge. 1990. Agricultural Competitiveness and Environmental Quality: What Mix of Policies Will Accomplish Both Goals? St. Paul: University of Minnesota, Center for International Food and Agricultural Policy. Each of these influences signals to producers the commodities they should produce and the technologies they should use. These choices, in turn, influence the farm's impact on the environment. This interaction of signals makes a policymaker's job difficult. It is not often clear how a change in policy will ultimately affect the decisions that producers make. Worries about the potential for trade-offs between protecting soil versus water, protecting surface water versus groundwater, and reducing loadings of nitrates versus loadings of pesticides have also confounded the policy making process. The multiplicities of potential objectives and best-management practices suggested to address those objectives have also made the choice of policies seem complicated. Simple recommendations that call for increased residue cover to reduce erosion or that suggest the installation of grassed waterways are no longer adequate to deal with the broader environmental problems facing agricultural producers.
OCR for page 32
Soil and Water Quality: An Agenda for Agriculture State and Local Government Policies The policies made by local and state governments are increasingly important factors. Local and state governments have often taken the lead in developing new programs and approaches for dealing with soil and water quality problems. Integrating the activities of various levels of government with various federal agencies has become an increasingly important element of environmental policy for agriculture. Characteristics of the Agricultural Sector The agricultural sector is too often discussed as if it were a homogeneous collection of uniform farms managed by similar producers. Many policies and programs are also based on the assumption of a "typical" producer. SOIL CONSERVATION IN COON CREEK, WISCONSIN In the early 1930s the Coon Creek Basin in southwestern Wisconsin was designated the first Soil Erosion Control Demonstration Area in the United States. The area is marked by steep slopes and narrow valleys, with relief of about 135 m (430 feet). The productive soils were formed from loess (an unstratified calcareous silt that overlies various sedimentary rock units on the steep slopes) and alluvial deposits. Settlers arrived in about 1850, and land clearing and cultivation continued until about 1900. In the early 1930s, when the soil conservation program began, the area showed the effects of 80 years of poor land management. At that time the soils were both degraded and eroded. The levels of sediments from sheet, rill, gully, and channel erosion were more than the streams could transport: more than 2 m (6 feet) of sediment was deposited in one 10-year period (McKelvey, 1939). The area was characterized by rectangular fields on steep slopes, up-and-down plowing of slopes, poor crop rotations, lack of cover crops, and overgrazed and eroding pastures and woodlands. Erosion, compaction, and depletion of organic matter and nutrients had degraded soil quality. Active rills and gullies were widespread, and the channels of the small upland tributary streams were entrenched and eroding. Studies here and in the general region showed that the conversion to agricultural land use was accompanied by increased flooding as well as erosion and sedimentation. The hydrologic changes, in turn, also caused major changes in the physical or geomorphic characteristics of the stream channels (Knox, 1977). The conservation demonstration project instituted widespread land treatment measures. The project increased the use of contour tillage and contour strip-cropping, instituted longer rotations with various cover crops, and
OCR for page 33
Soil and Water Quality: An Agenda for Agriculture In reality, farms differ in the commodities they produce, their soil quality, and their topography. Ownership patterns differ, too. Beef cattle farms are often small-scale, part-time farm operations with only a few head of cattle, whereas poultry enterprises tend to resemble vertically integrated industries ("vertically integrated" refers to an industry in which a single company provides the control) (Reimund and Gale, 1992). Cash grain farms most closely match the popular perception of agriculture: family farms run by owner-operators (Reimund and Gale, 1992). Just as farms are diverse, producers are also a diverse set of people who have a variety of goals: profit maximization, minimization of management time, maintenance of a certain life-style, protection of personal independence, desire to obtain a certain social status, and observation of a particular environmental or religious ethic. In addition, producers have different levels of skills, different levels of access to resources, and different sources of information. Such differences—particularly incorporated manure and crop residues into the soil. By the 1970s, when the area was reinvestigated by researchers from the U.S. Geological Survey, the conversion was complete and conservation tillage was being introduced as well (Trimble and Lund, 1982). Even with these changes, aggregate land use had changed little since 1930; the proportion of land in row crops, cover crops, and pastureland had changed little. Land management, however, had improved dramatically. The calculated erosion rates decreased by more than 75 percent, from more than 3,400 metric tons/km2 (15 tons/acre) in 1934 to about 720 metric tons/km2 (3 tons/acre) in 1975. The linear extent of gullies was reduced by 76 percent, with medium and large gullies nearly eliminated by 1978 (Fraczek, 1988). Trimble and Lund (1982) also systematically studied sedimentation rates in sediment basins and along the bottomlands of streams. Sediment deposition rates decreased by 98 percent or more from 1936 to 1945. Although erosion and sedimentation rates were still greater in the 1970s than before settlement and cultivation, the soil conservation programs greatly reduced erosion and sedimentation. Rills and gullies had mostly disappeared. The improved land management and soil quality increased water infiltration, decreasing runoff, reducing peak runoff and flood flows, and decreasing the erosion potential of streams as well. The area is a good example of the changing concerns for water quality and the need for improvements in input efficiency and input management approaches. In the 1990s, some watersheds in this area have been established as demonstration areas for Wisconsin's Nutrient and Pest Management Program and some areas have been designated atrazine (a pesticide) management areas, to focus on more recent concerns for nitrogen, phosphorus, and pesticide impacts on groundwater and surface water quality.
OCR for page 34
Soil and Water Quality: An Agenda for Agriculture when coupled with the differences in farm characteristics—can mean considerable differences in the reasons why producers choose to adopt or reject new farming systems (Nowak, 1992). TIME TO MOVE AHEAD Much has changed since 1970. The 1985 Food Security Act, the 1987 amendments to the Federal Water Pollution Control Act, the 1990 Coastal Zone Act Reauthorization Amendments, and the 1990 Food, Agriculture, Conservation and Trade Act produced a combination of new programs and mandates that can be used to address soil and water quality problems. Accelerated research has improved understanding of the physical, chemical, and biological processes that determine how agricultural systems affect soil and water quality. Experimentation with new production technologies and farming systems by researchers and producers has produced a wealth of information on the applicabilities and efficacies of innovative farming systems. Many of the mandates, programs, and knowledge needed to move ahead with an expanded agenda of soil and water quality improvement are available. What is needed is consensus on the broad objectives that the mandates, programs, and knowledge should achieve. This report is intended to help achieve that consensus.
Representative terms from entire chapter: