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Soil and Water Quality: An Agenda for Agriculture (1993)

Chapter: 3 A Systems Approach to Soil and Water Quality Management

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Suggested Citation:"3 A Systems Approach to Soil and Water Quality Management." National Research Council. 1993. Soil and Water Quality: An Agenda for Agriculture. Washington, DC: The National Academies Press. doi: 10.17226/2132.
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3
A Systems Approach to Soil and Water Quality Management

The preceding chapter defined four broad opportunities that should be pursued by national policies to prevent soil degradation and water pollution. These opportunities are to (1) conserve and enhance soil quality as the first step toward environmental improvement; (2) increase nutrient, pesticide, and irrigation use efficiencies in farming systems; (3) increase the resistance of farming systems to erosion and runoff; and (4) make greater use of field and landscape buffer zones. Realizing those opportunities depends on the ability and willingness of producers to change their management and production practices. Producers, however, do not make isolated changes in these practices. A change in one production or management practice affects other components of the farming system that producers manage. Programs and policies that pursue these four opportunities, therefore, should also incorporate a systems perspective.

LINKAGES AMONG OBJECTIVES

Inherent links exist among soil quality conservation, improvements in input use efficiency, increases in resistance to erosion and runoff, and the wider use of buffer zones. These links become apparent only if investigators take a systems-level approach to analyzing agricultural production systems. The focus of such an analysis is the farming system, which comprises the pattern and sequence of crops in space and time, the management decisions regarding the inputs and production practices that are used, the management skills, education, and objectives

Suggested Citation:"3 A Systems Approach to Soil and Water Quality Management." National Research Council. 1993. Soil and Water Quality: An Agenda for Agriculture. Washington, DC: The National Academies Press. doi: 10.17226/2132.
×

of the producer, the quality of the soil and water, and the nature of the landscape and ecosystem within which agricultural production occurs. An integrated systems approach is necessary for the development of policies and programs to accelerate the adoption of farming systems that are viable for producers, that conserve soil quality, and that do not degrade water quality (Jackson and Piper, 1989).

LINKAGES AMONG PROGRAMS

A broad range of programs at the local, state, and federal levels seek to solve the environmental problems associated with agricultural production.

FARMING SYSTEM PLANNING

Development of an integrated farming system plan begins with an inventory of farm resources. This inventory is meant to provide the data to answer some of the following questions:

  • Are there opportunities to improve pest, nutrient, or soil management through crop rotation?

  • Are there livestock enterprises on the farm or nearby farms from which animal manures might be collected and used as nutrient inputs?

  • What amount of pest control inputs have been used in the past?

  • How are irrigation applications scheduled?

  • Are land ownership or lease arrangements an obstacle to changes in farm management?

  • Does the producer participate in U.S. farm programs?

  • Does the equipment inventory allow or hinder the capability to improve tillage practices and residue management?

  • How soon is tillage, application, or other capital equipment scheduled for replacement?

  • How aware are producers of problems in their operations?

  • What are producers' perceptions of the risks involved in changing their current farming systems?

Once a general picture of the farm enterprise emerges, more detailed information on production practices needs to be assembled. Often, records of input use, soil tests, crop yields, and other data are not available and must be constructed as completely as possible from memory to answer the following questions:

  • What is the crop rotation history on a field-by-field basis?

  • Are credits for the nitrogen fixed by legumes taken when making fertilizer applications?

  • Has manure routinely been applied only to a small, particular area?

  • Have particular pest problems been associated with a particular field, a particular area within a field, or a particular crop or cropping sequence?

  • What do soil analyses indicate about the relative soil quality and soil fertility between fields?

Suggested Citation:"3 A Systems Approach to Soil and Water Quality Management." National Research Council. 1993. Soil and Water Quality: An Agenda for Agriculture. Washington, DC: The National Academies Press. doi: 10.17226/2132.
×

Ribaudo and Woo (1991) reported that various erosion control measures have been adopted by 17 states, nutrient control measures by 17 states, pesticide control measures by 16 states, land use control measures by 3 states, and input taxes by 4 states. A similar diversity of programs exists at the federal level (see Tables 1-1 and 1-2 in Chapter 1).

All of these local, state, and federal programs have specific objectives that address soil erosion; nutrient, pesticide, or irrigation water management; and protection of wetlands or other environmentally sensitive lands. The objectives of one program can conflict with, complement, or reinforce the objectives of other programs at the farm level, where the programs are ultimately implemented. Such inconsistency between the

  • Have fertilizers and nutrient management been used on a field-by-field basis or uniformly across the farm?

  • What have been the crop yields from individual fields?

At this stage improvements can begin. These might range from conservation plan improvements to input adjustments based on the results of soil tests. Fields or parts of fields where manure has been applied or legumes grown can be targeted for detailed soil sampling so that the producer can appropriately adjust fertilizer inputs.

Further refinements can be made by assessing the soil resources within each field since the soils within a field can vary dramatically. Adjustments to, for example, tillage practices and the inputs used can increase both the economic and environmental performance of the field. Fertilizer applications, for example, should be different on the top of a hill than on the side of a hill. Particular weed problems are often associated with microclimatic conditions related to the different soils located in different parts of the landscape. The yield potential can be much different on different soils in the same field; adjusting the inputs to the parts of the field with different yield potentials can increase input use efficiency.

The progression from whole-farm analysis to field-by-field and intrafield improvements is a process that takes place in steps. The producer can stop the process at any stage at which the increased cost of refined management is too high or information is not yet available to move to the next step. Movement from step to step requires better information management and improvements in the skills of the producer. Typically, implementation of such improved management requires development of a multiyear plan, which involves improved on-farm data collection, management alterations, and improved record keeping. Full implementation may be delayed until capital investment in new equipment or facilities is feasible, because of a multiyear crop rotation, or until the producer's experience with the new farming system removes doubts about its efficacy and allows the producer to overcome a perceived risk of economic loss resulting from implementation of the new farming system. In some instances, the plan is best implemented on a portion of the farm, side by side with the producer's normal management system, to increase confidence that the recommended changes will in fact work.

Suggested Citation:"3 A Systems Approach to Soil and Water Quality Management." National Research Council. 1993. Soil and Water Quality: An Agenda for Agriculture. Washington, DC: The National Academies Press. doi: 10.17226/2132.
×

objectives of different programs is most likely to occur when programs promote narrow technical solutions for individual problems. Multiple programs that promote different technical solutions to different problems at the farm level increase the chance for incompatibility. The linkages between program objectives become clearer if a systems approach is used to integrate activities at the local, state, and federal levels.

ADVANTAGES OF FARMING SYSTEMS APPROACH

Use of the farming system rather than individual best-management practices as the foundation for efforts to improve soil and water quality pays off in five ways:

  1. addresses resource and enterprise variability;

  2. provides a basis for targeting programs and financial support where improved soil and water quality is most needed;

  3. provides a basis for coordinating local, state, and federal programs;

  4. increases the chances of exploiting opportunities to simultaneously improve financial and environmental performance; and,

  5. increases the flexibility to adapt programs and policies to changing resource or market conditions.

Variability

Directing national policy toward solutions that improve soil and water quality has been made more difficult because of the geographic variability in the resources and enterprises that characterize agricultural production systems in the United States. This difficulty is exacerbated by the need to integrate the activities of local, state, and federal programs. A systems approach can be based on management principles that are applicable to the variable conditions of different farming systems and different regions. National-level programs can be based on-farming system plans that can be developed by using uniform criteria. Such uniform criteria can provide a more rigorous basis for determining whether producers or programs are meeting their objectives.

Targeting

Farming systems can be analyzed at regional scales to set national priorities. Analyzing nutrient inputs and outputs at regional scales, for example, is an effective way to target those regions where improvements in nutrient management are most likely. Figure 3-1 provides a regional breakdown of the balance between nutrient inputs and outputs

Suggested Citation:"3 A Systems Approach to Soil and Water Quality Management." National Research Council. 1993. Soil and Water Quality: An Agenda for Agriculture. Washington, DC: The National Academies Press. doi: 10.17226/2132.
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Figure 3-1 Proportion of national nitrogen and phosphorus inputs and balances contributed by each farm production region. Nitrogen and phosphorus balances are the differences between total nitrogen and phosphorus inputs and the nitrogen and phosphorus removed with the harvested crop or in crop residues. See the Appendix for a full discussion of the methods used to estimate nitrogen and phosphorus inputs, outputs, and mass balances.

Suggested Citation:"3 A Systems Approach to Soil and Water Quality Management." National Research Council. 1993. Soil and Water Quality: An Agenda for Agriculture. Washington, DC: The National Academies Press. doi: 10.17226/2132.
×

by farm production region. Directing efforts to improve nutrient management to those regions with the greatest balance of inputs over outputs is a first step toward targeting. This kind of analysis can be done at the farm, watershed, regional, or state level to further refine targeting efforts. Similar analyses could be conducted for irrigation water, pesticides, and other inputs.

Incorporating a farming system perspective, into targeting can also help identify those farming systems within those geographically defined priority areas that should be the focus of attention. Programs could be directed at farming systems that, because of their management or location, cause a disproportionate share of soil and water quality problems. The focus of targeting, then, would shift from defining geographic regions to identifying the opportunities to change farming systems within priority areas.

Integration

Farming systems analysis provides a way to integrate the objectives of environmental programs at the local, state, and federal levels. A farming systems approach, for example, helps to make clear the relationship between programs to reduce erosion and programs to improve nutrient management. The impacts of individual programs on-farming systems could be determined prior to implementation, and redundant or conflicting elements could be identified early in the policy design and implementation process.

Win-Win Opportunities

Systematic analysis of input use, cropping systems, and tillage practices increases the likelihood that opportunities to simultaneously improve financial and environmental performance will be identified. Accounting for on-farm resources, such as nutrients from legumes or manures, can lead to improvements in nutrient management that reduce costs as well as improve soil and water quality. Similarly, a more integrated approach to analysis of weed problems can identify weedy spots in fields that need special treatment, while pest control expenditures for other parts of the field can be reduced.

Win-win opportunities also exist for program managers. A farming system approach will result in recommendations that are more appropriate to specific farms, eliminate inconsistent and conflicting recommendations, and direct the attention of program managers to those clients most in need of technical assistance. Such an approach promises

Suggested Citation:"3 A Systems Approach to Soil and Water Quality Management." National Research Council. 1993. Soil and Water Quality: An Agenda for Agriculture. Washington, DC: The National Academies Press. doi: 10.17226/2132.
×

to increase the effectiveness of programs and the efficiency with which recommendations can be implemented by producers.

Adaptability

The same systems approach that is used at the enterprise level can be extended to the multiple-farm, landscape, watershed, or regional scales to direct targeting and program evaluation. Table 3-1, for example, presents the types of information and analyses that can be used at various scales to guide soil and water quality programs.

FARMING SYSTEM AS UNIT OF ANALYSIS AND MANAGEMENT

The farming system should be the unit of analysis and management used to direct local, state, and federal programs to protect soil and water quality.

Environmental programs to protect soil and water quality should be evaluated on the basis of the effects of the recommended management and production practices on the total farming system. Changes in the management of farming systems rather than the adoption of individual best-management practices should be the goals of environmental programs. The linkages among soil quality, input use, erosion and runoff, and buffer zones can be managed only at the farming system level. Similarly, the linkages among different local, state, and federal programs are best understood by analyzing how these programs affect farming systems. Failure to recognize and manage these inherent linkages increases the likelihood that trade-offs between protecting soil versus water quality, protecting surface water quality versus groundwater quality, or reducing the loadings of one pollutant versus another will impede progress toward overall improvements in soil and water quality.

Integrated Farming System Plans

Integrated farming system plans are the best mechanism available now for implementing a farming systems approach at the farm level. The current array of soil and water quality programs provides an opportunity to incorporate an integrated farming systems approach into U.S. Department of Agriculture (USDA) and U.S. Environmental Protection Agency (EPA) soil and water quality improvements efforts. The multiplicity of practices, objectives, and plans associated with these initiatives is a good example of the need for integrated farming system plans to coordinate the activities of different programs and agencies at the farm level.

Suggested Citation:"3 A Systems Approach to Soil and Water Quality Management." National Research Council. 1993. Soil and Water Quality: An Agenda for Agriculture. Washington, DC: The National Academies Press. doi: 10.17226/2132.
×

TABLE 3-1 Application of Farming System Approach at Different Geographic Scales

Geographic Scale

Farming System

Physical Resource Data

Socioeconomic Data

Inventories and Analyses

Farm Production Regions

Dominant farming systems in multistate regions characterized by similar soils, hydrology, and commodities produced

Soils, climate, and water availability

Income, production costs, and structure of commodity markets and agricultural sector

National Resources Inventory (SCS), production practices, costs of production, yields (ERS, NASS, Bureau of the Census), water quality monitoring (USGS, EPA, and state monitoring systems)

State or Regional Subdivisionsa

Farming systems characterized by similar pattern of crop or livestock production, e.g., cash grain, cash grain-beef-hogs, or irrigated potatoes

Distribution of highly erodible land, indicators of soil quality, and surface water and groundwater quality monitoring

Fluctuations in commodity and input prices, capital requirements, off-farm employment opportunities, land tenure

Regional nutrient, pesticide, and irrigation mass balances; geographic information systems; hydrologic models; variability in production practices among producers; and segmentation of producers into target markets for program delivery

Farm

Pattern of input use, crop rotations, and livestock production in both space and time

Soil mapping, indicators of soil quality, drainage, and existing conservation plans

Producer attitudes, skills, goals; available equipment, capital and labor; land ownership; and participation in federal agricultural programs

History of soil test results, crop and livestock production, pest problems, irrigation scheduling, input use, and tillage practices

Field

Within-field patterns of pest problems, moisture, and fertility and culture practices

Soil testing keyed to soil mapping units; within-field history of nutrient, pesticide, and irrigation use; and identification of localized pest or fertility problems

Field or production unit efficiency, e.g., yield goals versus historical yields achieved, costs per kilogram of commodity produced, and year-to-year variability in costs and returns

Use of soil tests, soil maps, enterprise records of yields, pest problems, and input use to adjust production practices to variations in soils, drainage, or landscape position within the field

NOTE: SCS, Soil Conservation Service, USDA; ERS, Economic Research Service, USDA; NASS, National Agricultural Statistics Service, USDA; USGS, U.S. Geological Survey, U.S. Department of the Interior; EPA, U.S. Environmental Protection Agency.

a State and regional subdivisions could include, for example, watersheds, major land resource areas, crop reporting districts, or other regions.

Suggested Citation:"3 A Systems Approach to Soil and Water Quality Management." National Research Council. 1993. Soil and Water Quality: An Agenda for Agriculture. Washington, DC: The National Academies Press. doi: 10.17226/2132.
×

The development and implementation of approved integrated farming system plans should be the basis for delivery of educational and technical assistance, should be the condition under which producers become eligible for cost-sharing dollars, and should be the basis for determining whether producers are complying with soil and water quality programs.

Current programs, whether voluntary or nonvoluntary, are all based on a conservation planning approach. Plans are required for Conservation Compliance, Water Quality Incentive Program, the Integrated Farm Management Program option, and different elements of USDA's water quality initiatives. In addition, contracts that specify the practices that the producer should follow are required for the Conservation Reserve Program and for Agricultural Conservation Program cost-sharing agreements. Similar conditions of use and management are established in easements under the Wetland Reserve Program. Other plans will be required to comply with provisions of the 1990 Coastal Zone Management Act Reauthorization Amendments (PL 101-508).

It is possible that a single producer could be required to implement

  • a conservation compliance plan stipulating erosion control measures for those fields that are highly erodible;

  • a cost-sharing agreement with the Agricultural Stabilization and Conservation Service of USDA stipulating the management practices required to maintain a specific structure, such as a terrace or grassed waterway, for which the producer receives cost-sharing dollars;

  • a water quality plan tied to receipt of incentive payments under the Water Quality Incentives Program; and, increasingly,

  • a nutrient management plan to meet the requirements of state water quality regulations.

The effectiveness of these programs and plans will be increased if they are based on a single integrated farming system plan that balances multiple objectives and ensures that single-objective best-management practices designed to reduce erosion, improve nutrient and pest management, or improve the management of irrigation water, for example, are not working at cross purposes.

The objectives of conservation efforts are multiple; the traditional concern for reducing soil erosion has been combined with the need to reduce loadings of nutrients, pesticides, salts, and sediments to surface water and groundwater. Encouraging or requiring the adoption of single-objective best-management practices is no longer a sufficient basis for soil and water quality programs at the farm level.

Integrated farming system plans that address (1) conservation and enhancement of soil quality, (2) increased input use efficiencies, (3)

Suggested Citation:"3 A Systems Approach to Soil and Water Quality Management." National Research Council. 1993. Soil and Water Quality: An Agenda for Agriculture. Washington, DC: The National Academies Press. doi: 10.17226/2132.
×

increased resistance of soil to erosion and runoff, and (4) field and landscape buffer zones are needed if the multiple objectives of improving soil and water quality are to be met and trade-offs are to be minimized.

The Soil Conservation Service of USDA is beginning to use integrated farming system plans through its proposed Resource Management System. The Soil Conservation Service proposed that resource management systems address multiple objectives and the best-management practices that can be integrated into a farming system plan to improve soil and water quality.

The first step toward implementing a farming systems approach to improving soil and water quality should be to replace current single-objective plans required to receive financial assistance through the Agricultural Conservation Program, Water Quality Incentives Program, and other programs with integrated farming system plans.

Receipt of cost-sharing dollars should be conditional on the development of an integrated farming system plan that clearly specifies how the

WIN-WIN OPPORTUNITIES: A SYSTEMS APPROACH ON A PENNSYLVANIA DAIRY FARM

Lanyon and Beegle (1989) studied a 56-ha (138-acre) dairy farm in central Pennsylvania as a model for whole-farm planning to improve nutrient management. The farm is a good example of how a farming system approach can improve soil, water quality, and profitability.

Lanyon and Beegle calculated nutrient balances using the producer's records of crop yields; the amounts of fertilizer and manure applied; sales of crops, milk, and livestock; and the amount of livestock feed purchased. Nutrient budgets for individual fields revealed that substantial reductions in the amount of nitrogen, phosphorus, and potassium were possible if inputs from manure were properly credited. The data for one corn field, for example, revealed that manure provided 277 percent as much phosphorus and 463 percent as much potassium as was removed by the corn crop. Application of purchased sources of these nutrients, except for starter fertilizers, could be suspended. The amounts of phosphorus and potassium applied to the alfalfa field were less than those removed by the crop, but soil tests revealed very high levels of phosphorus and potassium in the soil and supplementary applications of phosphorus and potassium to alfalfa were not needed. The use of on-farm supplies of nitrogen, phosphorus, and potassium from manure and legumes reduces production costs and the potential for losses of nutrients to surface water or groundwater.

The results for the nitrogen, phosphorus, and potassium balances in the livestock unit suggest that improvements in manure collection and manure storage facilities could substantially increase the efficiency with

Suggested Citation:"3 A Systems Approach to Soil and Water Quality Management." National Research Council. 1993. Soil and Water Quality: An Agenda for Agriculture. Washington, DC: The National Academies Press. doi: 10.17226/2132.
×

cost-sharing practice or structure supports implementation of the farming system plan. Implementation of the farming system plan, in addition to maintenance of the cost-sharing practice or structure, should be required as a condition of the cost-sharing agreement. The planning and implementation requirements for the Water Quality Incentives Program already approach this recommendation.

In the long-term, the implementation of an integrated farming system plan should be required for producers in regions where soil and water quality problems are severe regardless of their participation in federal farm programs.

About 55 million ha (135 million acres) of U.S. cropland (about 32 percent of all U.S. cropland) will be subject to Conservation Compliance erosion control plans if producers want to receive federal farm program benefits. Full implementation of Conservation Compliance plans on these lands should help to improve soil quality and increase the soil's resistance to erosion and runoff. Soil and water quality benefits from implementation of these compliance plans could be much more comprehensive, however,

which producers can use the nutrients in manure. Purchased feed contributed substantially to the total nutrient flow in the farm. The nitrogen, phosphorus, and potassium supplied to the livestock enterprise from on-farm sources alone, however, provided 125 percent of the nitrogen, 87 percent of the phosphorus, and 186 percent of the potassium accounted for in livestock products and manures, suggesting that there may be substantial opportunities to refine the composition of livestock feed.

The systematic analysis of this dairy farm revealed that the best means of improving environmental and financial performance are to

  • make better use of on-farm nutrient sources by redistributing nutrients to fields on the basis of soil test results, nutrient application history and crop history;

  • make better use of on-farm nutrient sources by improving manure collection and storage to reduce manure losses from the barnyard; and

  • refine the feed composition, which would perhaps reduce the need for purchased feeds.

Implementation of a single best-management practice, increased soil testing, or construction of manure storage facilities, for example, would address only one component of what is required to improve nutrient management on the dairy farm. The effectiveness of soil testing or manure storage facilities will be greatly increased if they are part of a more comprehensive nutrient management approach. It is the nutrient management approach, not the practices adopted, that determine success. Similarly, it is the management approach, as reflected in an integrated farming system plan, that should be the basis of efforts to improve soil and water quality.

Suggested Citation:"3 A Systems Approach to Soil and Water Quality Management." National Research Council. 1993. Soil and Water Quality: An Agenda for Agriculture. Washington, DC: The National Academies Press. doi: 10.17226/2132.
×

if they were based on integrated farming system plans that address input use efficiency and buffer zones in addition to soil erosion.

Even if fully implemented, compliance mechanisms will not rectify all soil and water quality problems because they cover only selected crops and producers (Ribaudo, 1986) and address erosion only from highly erodible lands. Evidence also suggests that compliance mechanisms, as they currently are designed and implemented, may not address many important water quality problems (Ribaudo and Young, 1989). Compliance plans, as they are currently required, do not address compaction, salinization, or other forms of soil degradation. Nutrient, pesticide, and irrigation management plans are also not addressed under Conservation Compliance plans, and the 68 percent of cropland not under Conservation Compliance plans may include important sources of soil degradation and water pollution.

Erosion control on highly erodible lands alone, while important, will not adequately control loadings of nutrients, pesticides, salts, and sediments to surface water and groundwater. Programs need to be targeted at problem areas and at problem farms (see section later in this chapter for a discussion of targeting). Croplands other than, or in addition to, those that are highly erodible will have to be included in these programs. Similarly, producers other than, or in addition to, those participating in federal farm programs will have to be added. An integrated approach that addresses all four components of the farming system (soil quality, input use efficiency, resistance to erosion and runoff, and buffer zones) will be needed.

Rigorous Planning Standards

Rigorous planning standards are needed to increase the confidence that implementation of integrated farming system plans will result in real improvements in soil and water quality. Such standards are needed whether voluntary or nonvoluntary approaches to the development and implementation of integrated farming system plans are used.

USDA and the EPA should convene an interagency task force to develop planning standards that can be used as the basis for implementation of the Resource Management System by the Soil Conservation Service of USDA and as guidance for state governments that meet the requirements of the Federal Water Pollution Control Act (PL 100-4) and the 1990 Coastal Zone Management Act Reauthorization Amendments (PL 101-508).

Integrated farming system plans to improve soil and water quality should, at a minimum, specify how recommended farming practices (1)

Suggested Citation:"3 A Systems Approach to Soil and Water Quality Management." National Research Council. 1993. Soil and Water Quality: An Agenda for Agriculture. Washington, DC: The National Academies Press. doi: 10.17226/2132.
×

conserve or enhance soil quality, (2) increase input use efficiency, (3) increase resistance to erosion and runoff, and (4) incorporate field and landscape buffer zones into the farming system. A large body of information and models are already available to establish more rigorous standards for these criteria. That body of research should be used to prepare and evaluate integrated farming system plans.

Soil Quality

Standards for soil quality have not yet been developed, although efforts are under way in the Soil Conservation Service and the U.S. Forest Service of USDA to develop such standards (see sections on soil quality in this chapter and in Chapter 5 for a full discussion). As a starting point, the following indicators of soil quality should be used as standards to evaluate the effects of implementing the farming practices that are recommended for an integrated farming system plan: nutrient availability, amount of organic carbon, amount of labile carbon, texture, water-holding capacity, structure, maximum rooting depth, salinity, acidity, and alkalinity.

Input Use Efficiency

The criteria needed to evaluate input use efficiency vary depending on whether nutrients, pesticides, or irrigation water is being addressed (see sections on input use efficiency in this chapter and in Chapters 6 to 8 and 10 and 11 for a full discussion). Considerable experience has been gained in the last few years in preparing nutrient, pesticide, and irrigation management plans. Several states have already developed best-management practices and plans for nutrients, pesticides, and irrigation water. In addition, knowledge gained from the Management Systems Evaluation areas project (an interagency effort to evaluate the effect of agricultural management practices on water quality) can provide information from which to develop standards for input management plans. The management measures developed to implement the 1990 Coastal Zone Management Act Reauthorization Amendments are another source of information. Information available from these sources should be assembled to develop uniform criteria that can be applied to nutrient, pesticide, and irrigation management plans.

Resistance to Erosion and Runoff

Erosion prediction models such as the universal soil loss equation and the revised universal soil loss equation can predict the effects that

Suggested Citation:"3 A Systems Approach to Soil and Water Quality Management." National Research Council. 1993. Soil and Water Quality: An Agenda for Agriculture. Washington, DC: The National Academies Press. doi: 10.17226/2132.
×

Water runoff from a cotton field, having passed through the grass hedge (behind the agronimist), is recorded on a hygrographic chart. Credit: Agricultural Research Service, USDA.

residue management, cover crops, and other measures have on increasing the resistance of farming systems to erosion and runoff. These models are sufficient for comparing the relative effectiveness of recommended measures to increase resistance to erosion and runoff (see the section on resistance to erosion and runoff in this chapter and in Chapter 9).

Buffer Zones

Four criteria—size, location, species selection, and vegetative management—are most important for evaluating the effectiveness of field-scale buffer or vegetative filter strips (see sections on buffer zones in this chapter and in Chapter 12). A substantial body of research and experience with vegetative filter strips within or bordering crop fields is accumulating. Models such as GRAPH (Lee et al., 1989) and GRASSF (Barfield et al., 1979; Hayes et al., 1979) have been developed to predict the amount of sediment and nutrient trapping in vegetative filter strips. This information can be used to establish criteria for size, location, species selection, and management of field-scale buffer strips. The U.S.

Suggested Citation:"3 A Systems Approach to Soil and Water Quality Management." National Research Council. 1993. Soil and Water Quality: An Agenda for Agriculture. Washington, DC: The National Academies Press. doi: 10.17226/2132.
×

Forest Service has produced specific guidelines for riparian buffer zone planning, design, and maintenance (Welsch, 1991). These guidelines call for three zones, each under a different management system depending on distance from the stream and the intensity of use of adjacent uplands.

Need for Performance Standards

Integrated farming system plans that specify a combination of production and information management practices are the best tools available now to guide efforts to prevent soil degradation and water pollution. In the long-term, however, standards based on more quantitative estimates of soil degradation and water pollution caused by farming practices are needed. These standards are needed to ensure that soil and water quality goals are met and that unnecessary requirements are not imposed on producers.

In some cases of industrial pollution, polluters are required to meet performance standards based on water quality criteria applied to their discharges or to the water body that receives those discharges. Polluters are allowed to discharge a certain level or load of pollutants; or, in other cases, groups of polluters work together to achieve a given level of ''receiving water" quality. In either case, water quality goals and the obligations of the polluters are unambiguous. Moreover, the performance standard approach that requires achieving a specified water quality standard rather than specifying the control technology that should be used allows polluters to develop innovative strategies for achieving compliance.

It is difficult to apply a performance standard approach to nonpoint source pollution in general and to agricultural nonpoint source pollution in particular (Abler and Shortle, 1991; Foran et al., 1991; Roberts and Lighthall, 1991). It is difficult to measure pollutant outputs from specific farm fields, and it is difficult to identify pollutants from specific areas in a degraded water body. The alternative to performance standards is a "design standard" approach. In a design standard approach, polluters come into compliance by implementing a set of approved practices. This is the approach taken in the 1990 Coastal Zone Management Act Reauthorization Amendments (PL 101-508), which requires the development of an enforceable program of management measures to control nonpoint source pollution in coastal areas.

The drawback of design standards, including integrated farming system plans, is that they do not guarantee the achievement of a given level of soil or water quality. Moreover, design standards can be

Suggested Citation:"3 A Systems Approach to Soil and Water Quality Management." National Research Council. 1993. Soil and Water Quality: An Agenda for Agriculture. Washington, DC: The National Academies Press. doi: 10.17226/2132.
×

confining, limiting the options of a producer to improve the environmental performance of a production system.

In the short-term, design standards, such as the integrated farm management planning standards discussed here, are the best that can be done with current models and data. There is an urgent need, however, to develop a performance standard approach for improving the environmental performance of farming systems. Developing such an approach requires several steps to quantify how the agricultural management practices used on a field affect the water quality in the problem water body or aquifer. First, the lowest level of sediment, nutrient, pesticide, salt, and trace element output that can be achieved with current best-management practices in different parts of the United States needs to be determined. The current Management Systems Evaluation Area network of sites should be able to provide these data for many parts of the country. Second, there is a need for models capable of depicting edge-of-field and bottom-of-the-root-zone pollutant outputs on a field-by-field basis. Model development toward this end is proceeding slowly and may need to be stimulated (see below). Once these steps are taken, researchers can begin to evaluate agricultural nonpoint source pollutant outputs against water quality discharge and can begin to develop receiving water quality criteria on a field-by-field and watershed-by-watershed basis.

Use of Models

Substantial advances have been made in mathematical modeling and computer simulation modeling of agricultural nonpoint source pollution problems that can help develop standards for integrated farming system plans. These modeling efforts range from simple conceptual mass balances to sophisticated research models.

Purposes, Advantages, and Limitations of Modeling

Investigators have used models to evaluate the extent of water pollution caused by management practices as well as to simulate water quality improvements under alternative management scenarios. Sensitivity analyses on model parameters and coefficients may identify which management practices would yield the greatest net change in soil or water quality. Modeling and models are not, however, a panacea for problem solving; they serve only as tools. Models typically reflect the model builder's perception of the problem and not necessarily that of the agronomic researcher or the resource manager. A model developed for site-specific conditions often cannot be used as a generic model, and

Suggested Citation:"3 A Systems Approach to Soil and Water Quality Management." National Research Council. 1993. Soil and Water Quality: An Agenda for Agriculture. Washington, DC: The National Academies Press. doi: 10.17226/2132.
×

vice versa. The precise and unambiguous language of mathematics and computer science is used in models, but in reality, models are only a substitute for the behavior of real-world systems.

Furthermore, some research models that are finely tuned require extensive input and model coefficients that are not normally measured and that are difficult or extremely costly to obtain. Simple mass balance models typically do not have the requisite characteristics to provide simulations over shorter time scales (for example, daily or monthly) or spatial scales (for example, hectares). Despite these problems, models may serve as valuable tools when properly applied and when proper recognition is given to the underlying assumptions and specificity.

Models of Nonpoint Source Pollution

A wide array of models address agricultural nonpoint source pollution. Many of them have been calibrated and validated with soil columns in the laboratory and intensively monitored plots in the field. Fewer models have been validated under field conditions with or without cropping. In a few instances, a given model has been tested at several localities or several models have been tested comparatively on a monitored field site.

A concerted effort is being made to develop or modify currently available models to assess agricultural nonpoint source pollution problems in cropping systems. For instance, Hanks and Ritchie (1991) promoted the use of computer models as a partial substitute for experimental research to determine agronomic recommendations. In addition, many states have now developed geographic information systems for natural resource inventory and management.

The Committee on Ground Water Modeling Assessment (National Research Council, 1990) assessed the development and use of ground water containment models for scientific and regulatory applications. That committee concluded that there is a range of capability in modeling fluid flow but had some concerns about the reliability of these models. Although prototype models exist for the reactivity and transport of contaminants, they have not yet been developed for use in practice (for example, regulatory applications).

A similar overall assessment of agricultural nonpoint source pollution models has not been made, other than to identify research needs. However, there is a growing body of literature about the utility of models that consider climate, soils, and crops for agricultural applications. The potential for improved and accurate agronomic simulation models is anticipated in the near future, and their role in assessing the

Suggested Citation:"3 A Systems Approach to Soil and Water Quality Management." National Research Council. 1993. Soil and Water Quality: An Agenda for Agriculture. Washington, DC: The National Academies Press. doi: 10.17226/2132.
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effect of alternative farming systems on agricultural nonpoint source pollution problems is expected to become increasingly valuable.

On-Farm Record Keeping

The first step toward implementing a farming systems approach is to develop information on a field-by-field basis. Many of the data needed to develop and implement integrated farming system plans are available only if producers keep good records of their management practices and yields.

Record keeping should be an essential component of integrated farming system plans.

The lack of good information about the farming operation can be a serious impediment to the development of integrated farming system plans. At a minimum, all producers should be encouraged to keep records of the inputs and tillage practices used, crop sequence, and crop yields on the field or enterprise level. Record keeping should be mandatory when integrated farming system plans are the basis on which financial assistance is received or for ensuring compliance with soil or water quality laws. Record keeping during and after the implementation of an integrated farming system plan is critical for providing the steady flow of information needed to evaluate and adjust the farming system plan. The systems established to manage the flow and analysis of information are as important or more important than the specific management practices specified in the plan. The development of record keeping systems that link agronomic and financial decisions should be a high priority. Policies that encourage or mandate the collection and use of information by the producer may, in the long-term, prove to be more effective than encouraging or mandating the use of best-management practices.

Record keeping has important benefits for the producer as well as governments. Record keeping is essential for refining enterprise management to increase profits. The information needed to manage a farm operation to maximize profit, if properly organized, will complement the information needed to improve soil and water quality. Collection and organization of this information is a way to improve profitability as well as soil and water quality.

Developing Capacity at the Local Level

Providing the technical assistance to develop and implement integrated farming system plans will tax the current capabilities of federal,

Suggested Citation:"3 A Systems Approach to Soil and Water Quality Management." National Research Council. 1993. Soil and Water Quality: An Agenda for Agriculture. Washington, DC: The National Academies Press. doi: 10.17226/2132.
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state, and local government agencies. The development of the capacities of both the public and the private sectors to deliver technical assistance to farmers should be a primary goal of agricultural environmental policy.

Public-Sector

The Soil Conservation Service, in cooperation with the Cooperative Extension Service, should undertake an accelerated training effort targeted at federal, state, and local government personnel and at producers to develop and implement integrated farming system management plans.

The technical capacities of county Soil Conservation Service, Agricultural Stabilization and Conservation Service, county Soil and Water Conservation Districts, and other personnel to develop and implement integrated farming system plans are variable. Expertise at the local level has been developed primarily to provide technical assistance for erosion control. The capacity to develop and implement integrated farming system plans requires broader technical understanding of input management, the transport of agricultural chemicals to water bodies, and the economics of farm planning. Training programs are urgently needed to develop this expertise at the local level.

Private-Sector

Mechanisms should be developed to augment public-sector efforts to deliver technical assistance with nonpublic-sector channels and to certify the quality of the technical assistance provided through these channels.

Development and implementation of integrated farming system plans at the farm level can be facilitated by public-sector programs—through the Cooperative Extension Service, the Soil Conservation Service, Soil and Water Conservation Districts, and the Agricultural Stabilization and Conservation Service; but many of the services needed to assist producers are increasingly provided by the private-sector. Table 3-2, for example, shows the results of a survey conducted by American Farmland Trust to determine the sources of information producers use to make tillage, fertility, or weed and insect control decisions. Five hundred farmers in Washington state, California, Minnesota, Illinois, and Georgia were surveyed. Fertilizer, herbicide, or insecticide dealers; other farmers; and family members stand out as the most important sources used by the surveyed farmers. Public-sector sources of information were relatively untapped, at least directly, by these farmers when making their decisions.

Suggested Citation:"3 A Systems Approach to Soil and Water Quality Management." National Research Council. 1993. Soil and Water Quality: An Agenda for Agriculture. Washington, DC: The National Academies Press. doi: 10.17226/2132.
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TABLE 3-2 Ranking of Information Sources by Surveyed Farmers

 

Percentage of Farmers Ranking Source as First or Second Most Importanta

 

Tillage

Fertility

Weed and Insect Control

Information Source

First

Second

First

Second

First

Second

CES staff

8

5

8

3

9

6

CES publications, meetings, or field days

5

4

4

5

3

5

SCS or CD staff

2

3

<1

1

0

<1

SCS or CD publications, meetings, or field days

1

2

1

2

<1

<1

ASCS staff

2

2

1

1

1

0

ASCS publications, meetings, or field days

1

1

1

1

0

<1

Staff and publications of other public agencies

1

1

1

1

<1

1

Farm organization staff

2

2

2

2

2

1

Fertilizer dealer

28

9

56

16

18

6

Herbicide or insecticide dealer

5

14

2

12

40

18

Fertilizer or pesticide applicator

1

2

<1

4

3

4

Other farmers

17

20

8

23

6

27

Family member

10

13

8

10

6

9

Nonprofit, educational, or environmental organization

1

1

<1

1

0

<1

Farm magazines, journals, and radio and television programs

8

13

2

12

2

11

Other

5

1

5

3

4

2

No response

5

10

1

1

NA

NA

NOTE: CES, Cooperative Extension Service, USDA; SCS, Soil Conservation Service, USDA; ASCS, Agricultural Stabilization and Conservation Service, USDA; CD, county Soil and Water Conservation District; NA, not available.

a Mean of reported percentages of farmers surveyed in Whitman County, Washington; Butte County, California; Renville County, Minnesota; Livingston County, Illinois; and Dooly County, Georgia.

SOURCE: Adapted from J. D. Esseks, S. E. Kraft, and L. K. Vinis. 1990. Agriculture and the Environment: A Study of Farmer's Practices and Perceptions. Washington, D.C.: American Farmland Trust.

Suggested Citation:"3 A Systems Approach to Soil and Water Quality Management." National Research Council. 1993. Soil and Water Quality: An Agenda for Agriculture. Washington, DC: The National Academies Press. doi: 10.17226/2132.
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Although private-sector service-oriented programs have proved successful for producers of specialty crops in the Southeast and Pacific regions, there has been relatively little development of such services for use by producers of the major commodity crops such as corn, wheat, and soybeans. The private-sector may require some encouragement to develop the willingness and capability to deliver these services. Quality control and quality assurance are also needed to ensure that the technical assistance delivered by the private-sector is adequate. Spiker and colleagues (1990), for example, found it difficult to determine whether the use of soil tests affected rates of fertilization because of the widely varying nutrient and fertilizer recommendations and applications that follow testing. Efforts to develop certification procedures and to increase the capacities of nonpublic-sector channels should go hand in hand.

TARGETING PROBLEM AREAS AND FARMS

The importance of targeting—that is, attempting to direct technical assistance, educational efforts, financial resources, or regulations to those regions where soil and water quality improvements are most needed, or to those farm enterprises that cause a disproportionate portion of soil and water quality problems—is difficult to overstate. Finding ways to target programs to well-defined regions and farm enterprises has become even more important as the problems that these programs address has expanded from soil erosion to water quality. The need for refined targeting has been made more urgent as federal, state, and local policymakers have struggled to stretch sometimes shrinking budgets to keep up with the increasing list of items on the environmental problem agenda.

Chapter 2 recommended an ambitious set of objectives for a national effort to improve soil and water quality, and the previous section of this chapter emphasized the need to expand efforts at the farm level by taking a systems approach to soil and water resource management. Such an expanded agenda cannot be implemented unless it is targeted at well-defined problems and farm enterprises. The inability or unwillingness to target policies, whether voluntary or nonvoluntary, only at areas where the need to improve soil and water quality is greatest or only at those farm enterprises responsible for soil and water quality damages is a major obstacle to efforts to make soil and water quality programs more effective.

Targeting of programs to regions and farm enterprises where those programs are most needed requires information about soil degradation,

Suggested Citation:"3 A Systems Approach to Soil and Water Quality Management." National Research Council. 1993. Soil and Water Quality: An Agenda for Agriculture. Washington, DC: The National Academies Press. doi: 10.17226/2132.
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water pollution, and producers' production practices. Ideally, the decision to target programs at particular regions or enterprises should be based on an

  • articulation of national or state goals for soil and water quality;

  • identification of regions where the benefits from achieving the goals per dollar invested are greatest;

  • identification of the linkages among farm practices, soil quality, and water quality; and

  • identification, within a targeted region, of those enterprises that contribute to the problem as well as their barriers to changing their farming systems.

Figure 3-2 illustrates how this information could be arrayed three-dimensionally to identify those regions and producers at which programs should be targeted. The highest priority for programs to change farming systems would be where soil and water quality degradation and the potential to improve producer's management are greatest.

Unfortunately, the data needed to construct the three-dimensional targeting scheme proposed in Figure 3-2 often are not available. The need to improve targeting, however, is urgent, and new approaches are needed to identify the regions and enterprises that should receive the greatest attention. The information available for guiding targeting efforts will, most likely, always be less than ideal. It is urgent that means be found to move ahead with the information that is available now. The targets identified by using this information may not be as refined as policymakers and program managers might like, but even crude targeting will help reduce the costs and increase the effectiveness of current programs to improve soil and water quality.

Soil and Water Quality Monitoring

Most efforts to target programs where they are most needed have been based on identifying those geographic regions where soil degradation and water pollution are most severe. These efforts have produced considerable amounts of information that could be used by policymakers and program managers to target soil and water quality programs at better-defined geographic regions. This information, however, has been collected by different agencies and for different purposes and has been based on different measures of soil or water quality. This information needs to be assembled and synthesized to identify priority regions.

The Secretary of USDA and the Administrator of EPA should undertake a coordinated interagency effort to identify regions or watersheds that should be the

Suggested Citation:"3 A Systems Approach to Soil and Water Quality Management." National Research Council. 1993. Soil and Water Quality: An Agenda for Agriculture. Washington, DC: The National Academies Press. doi: 10.17226/2132.
×

FIGURE 3-2 Conceptual diagram of three-dimensional targeting.

highest priorities for federal, state, and local programs to improve soil and water quality.

Federal, state, and local governments have identified priority areas for various soil and water quality problems and for various programs to improve soil and water quality. A few of these efforts are described below.

Soil Quality

The USDA has developed criteria and data to identify highly erodible lands, that is, lands that are most vulnerable to accelerated rates of

Suggested Citation:"3 A Systems Approach to Soil and Water Quality Management." National Research Council. 1993. Soil and Water Quality: An Agenda for Agriculture. Washington, DC: The National Academies Press. doi: 10.17226/2132.
×

erosion if they are not properly managed. The definition of these lands has been central to the implementation of Conservation Compliance, Conservation Reserve Program, and Sodbuster. Although erosion alone does not address all of the forces affecting soil quality (see Chapters 2 and 5 for a full description), the distribution of highly erodible land should be an important criterion used to identify priority regions. The extent of salinization of soils has also been monitored by the Soil Conservation Service as well as by state governments and international organizations. These data are also available to help define priority regions. As discussed in Chapters 2 and 9, the volume and energy of runoff from agricultural lands are closely related to but are not the same as rates of erosion. The Soil Conservation Service and the Agricultural Research Service should assemble the data and models available now to identify agricultural lands that should be included as priority areas based on the expected volume and energy of runoff caused by a lack of proper management.

Water Quality

Several efforts have been made by federal agencies and state and local governments to identify priority areas for water pollution control. The EPA is currently assembling data from assessments of nonpoint sources of water pollution that were conducted by each state under the provisions of the 1987 amendments to the Federal Water Quality Protection Act (PL 100-104) and is expected to use these data to identify priority areas for the control of nonpoint source pollution of surface waters. Similarly, the USDA identified 74 hydrologic unit areas to receive priority attention under the USDA's water quality initiative (Mussman, 1991). Congress has also identified the Chesapeake Bay watershed and the Great Lakes watershed as priority areas for water pollution control and, through the 1990 Coastal Zone Management Act (PL 100-508), it has mandated that watersheds that contribute to degradation of coastal wetlands and estuaries should be priorities for water pollution control. It is essential that the definition of priority areas under these programs be coordinated, and the data used to define these areas should be used to help define national priorities for soil and water quality improvements.

Monitoring Production Practices

The benefits of targeting efforts on the basis of soil and water quality data that define where resource damages are most severe are widely

Suggested Citation:"3 A Systems Approach to Soil and Water Quality Management." National Research Council. 1993. Soil and Water Quality: An Agenda for Agriculture. Washington, DC: The National Academies Press. doi: 10.17226/2132.
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accepted. The benefits, however, of using data on producers' production practices and enterprise characteristics have often been overlooked. Adding the third dimension—information on production practices and enterprise characteristics (Figure 3-2)—to the process of identifying targets will help in three ways: by identifying problem farms within priority areas identified by soil and water quality criteria alone, by identifying changes in the management of farming systems that should be sought within priority areas, and by identifying the barriers to adoption of improved farming systems that need to be overcome.

Problem Farms

The Secretary of USDA and the Administrator of EPA should initiate a multiagency effort to assemble currently available data on production practices and enterprise characteristics to identify problem farms within priority areas for soil and water quality improvements.

Although systematic data on production practices, input use, and management systems are scarce, those studies that are available clearly suggest the benefits of targeting programs to those farm enterprises that cause the most damage to soil and water quality. Padgitt (1989) found, for example, that about 25 percent of the Iowa farmers surveyed applied fertilizer at a level of 28 kg/ha (25 lb/acre) above recommended levels. Similarly, Schepers and colleagues (in press) found that 14 percent of the land in the Central Platte Natural Resource District in Nebraska that they studied received nitrogen in excess of 100 kg/ha (89 lb/acre) of the recommended amounts. Other investigators have also found that some producers apply excessive nutrients: Hallberg and colleagues (1991) report on Iowa, and Bosch and colleagues (1992) report on two regions of Virginia.

Setia and Magleby (1988) found that targeting conservation tillage practices to the 4,452 ha (11,000 acres) that cause the most damage within the targeted watershed could reduce the cost of improving water quality from $139,000 to between $9,000 to $32,000 for each percentage point reduction in the amount of sediments. Targeting the farms that contribute the largest nutrient loadings in the watershed could reduce cost of improving water quality from $151,000 to between $11,000 and $43,000 for each percentage point reduction in nutrient loads. Similarly, Lee and colleagues (1985) found that directing improvement efforts to critical areas within a targeted watershed could reduce costs of improving water quality 5- to 10-fold.

In 1985, USDA's Agricultural Research Service and Economic Research Service concluded an analysis of the previous years' targeting

Suggested Citation:"3 A Systems Approach to Soil and Water Quality Management." National Research Council. 1993. Soil and Water Quality: An Agenda for Agriculture. Washington, DC: The National Academies Press. doi: 10.17226/2132.
×

efforts. Nielson (1986), drawing on that analysis, recommended that USDA concentrate its efforts on problem farms. The study indicated that few county Agricultural Stabilization and Conservation committees gave such targeting high priority.

Data from the studies mentioned above demonstrate the importance of recognizing that there are problem farms, that is, farm enterprises that because of their location and production practices and management techniques cause more soil and water problems than others. It is just as important to recognize that many farms cause no problems at all and that some are probably improving soil and water quality. Targeting programs at the set of farms that are responsible for most soil and water quality degradation will reduce the cost and increase the effectiveness of soil and water quality programs. Targeting can also prevent placing unnecessary burdens on those producers who are not causing damages and recognize those producers who are making positive contributions to improving soil and water quality.

Monitoring Progress

Tracking changes in production practices provides a way to monitor programs in the absence of adequate soil and water quality monitoring. Nutrient mass balances, for example, can be calculated and monitored in the absence of adequate data on nutrient loadings to surface water or groundwater. Over time, improvements in nutrient management should be indicated by changes in the relative proportion of nutrient inputs and their balance with crop outputs (see Hallberg et al. [1991] for examples of programs in Iowa). This approach can be linked to existing or planned soil and water quality monitoring to further refine targeting and program evaluation. Gianessi and colleagues (1986), for example, used a large data base that described discharges to the nation's waters from approximately 32,000 point and 80,000 nonpoint sources to identify regions that would show significant improvement in phosphorus concentrations as a result of upland erosion control. As such data bases become available and better refined, they can be combined with nutrient mass balance information to identify those regions where potential water quality benefits from improved farming systems are the greatest.

Changes in the use and distribution of irrigation water, pesticides, tillage systems, or other farming system components could also function as measures of success in improving farming systems. In a survey of Iowa, Duffy and Thompson (1991) showed that 88 percent of corn and soybeans were cultivated an average of 1.3 times, indicating a significant

Suggested Citation:"3 A Systems Approach to Soil and Water Quality Management." National Research Council. 1993. Soil and Water Quality: An Agenda for Agriculture. Washington, DC: The National Academies Press. doi: 10.17226/2132.
×

potential to reduce herbicide use through banding rather than broadcast applications. Yet, the survey indicates that banding is used only on about 15 percent of the land planted in corn and soybeans.

Refine Strategies to Change Producer Behavior

Analysis of data on production practices and enterprise characteristics when programs are being designed is essential for adapting national policies to local realities as the national policies are implemented (Rogers, 1983). Analysis of production practices and enterprise characteristics helps program managers understand the diversity of reasons that may account for a producer's decision not to adopt an improved farming system (Nowak, 1983, 1985; Nowak and Schnepf, 1987). When local program personnel begin to understand this diversity, they can begin to make use of program implementation tools that match the diversity of reasons for producers' nonadoption of management practices (Kelly, 1984; Lake, 1983).

An example of such an approach is provided by the Farm Practices Inventory (FPI) developed in Wisconsin. The FPI measures specific crop nutrient behaviors on a corn field identified by the respondents as being the most productive in that year. It also measures differences, if any, between the most productive and other corn fields. In addition, it contains an inventory of pesticide use and management practices, livestock inventories and manure management practices, and a series of items that measure farmstead design (for example, wells, storage, and waste disposal). The FPI also has a knowledge ''test" that measures the levels of knowledge and perception of the major attributes of a series of recommended practices. Finally, it measures a limited set of farm, personal, and communication items. The FPI was designed to meet three objectives in natural resources management in Wisconsin:

  • provide an accurate assessment of the agronomic behaviors of producers in Wisconsin relative to the patterns of nutrient and pesticide management;

  • segment target audiences, design appropriate educational strategies, and provide direction for allocating limited fiscal resources; and

  • evaluate the effectiveness of soil and water quality programs and actions.

Analysis of production practices and enterprise characteristics are needed before programs are implemented. Knowledge of prevailing agronomic practices and producers' belief systems, knowledge levels, and other characteristics helps in designing improved farming systems

Suggested Citation:"3 A Systems Approach to Soil and Water Quality Management." National Research Council. 1993. Soil and Water Quality: An Agenda for Agriculture. Washington, DC: The National Academies Press. doi: 10.17226/2132.
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that are relevant to the producers affected by the problem (Grunig et al., 1988). This type of knowledge can be used to determine exactly

  • what farm management and production practices contribute to soil and water quality degradation;

  • what changes in management are suitable given existing knowledge levels, the nature of current farming practices, and the flexibility to invest human capital or fiscal resources in new practices; and

  • what information and assistance mechanisms currently have high credibility and use among target populations.

Answers to these questions prior to program implementation will allow a level of targeting that is not now being used.

Regional and National Data Collection

Full implementation of an integrated approach to planning and directing programs to prevent soil degradation and water pollution will only be possible if information of the appropriate density and quality is available. Providing this information will require coordinated efforts at local, state, and national levels.

Concerted efforts at the state and local levels should be undertaken to collect new data and find ways to link data that is already collected for other purposes to provide the foundation for more integrated approaches to preventing soil degradation and water pollution.

In many cases, existing data are not well suited to integrated approaches to program planning and direction. National data on soil and water resources such as the National Resources Inventory provide useful information for large regional scales but are not dense enough for use in the county, watershed, or smaller scale applications required to implement a systems approach at the local level. Data available at the local level, such as that found in soil surveys, are often difficult to link with other data sets that have been assembled for different purposes, such as participation in federal farm programs or cropping histories assembled by county offices of USDA's Agricultural Stabilization and Conservation Service.

The lack of systematic data on production practices is a particularly serious obstacle to targeting, monitoring, and designing soil and water quality programs. When such information is available, it is often not geographically based or linked to physical information about soil and water quality degradation. This lack of linkage between relevant natural resource data, production practices, and socioeconomic data limits the

Suggested Citation:"3 A Systems Approach to Soil and Water Quality Management." National Research Council. 1993. Soil and Water Quality: An Agenda for Agriculture. Washington, DC: The National Academies Press. doi: 10.17226/2132.
×

ability to realize improved targeting and program direction from an integrated approach based on- farming systems (Fletcher and Phipps, 1991).

Geographic information systems (GISs) have the potential to greatly increase the usefulness of existing and provide new data to implement a systems approach to soil and water resource programs (Fletcher and Phipps, 1991). GISs are designed to collect, manage, analyze, and display data spatially; they can be used in combination with other models as a way to enhance targeting, planning, and directing programs.

For example, Prato and coworkers (1989) used a GIS to assemble and retrieve physical measures of erosion. The GIS was linked with a linear programming model to determine an economically efficient system for reducing pollution. The water quality effects of such economically efficient solutions were evaluated by using the Agriculture Nonpoint Source Model. A farm practices inventory obtained economic data that were combined with a microcomputer budget management system and an erosion planning model (Figure 3-3). Ultimately, the researchers designed a resource management system that would obtain the most income while making the desired reductions in pollutants. Reports by Tim (1992) and Hamlett and colleagues (1992) are also good examples of the potential to use GIS to target problem watersheds.

The collection of data and the development of GISs will greatly increase the ability to implement integrated approaches at the state and local levels. Similar improvements in data collection, particularly the collection of systematic data on production practices, are needed to implement a systems approach to developing and directing national policy.

The Economic Research Service, the National Agricultural Statistics Service, and the Soil Conservation Service should assemble currently available information to provide baseline information about production practices and agronomic behaviors.

The ability to target and direct programs is seriously constrained by the lack of comprehensive and representative data on the production practices and agronomic behaviors of agricultural producers. Few comprehensive and representative data are available on producers' nutrient, pesticide, and irrigation water management practices. Better, but still limited, information on tillage systems and erosion control practices is available. This lack of information makes it difficult to set realistic goals, identify the changes in farming practices that should be sought through environmental programs, or evaluate how effective programs have been and what remains to be done.

Suggested Citation:"3 A Systems Approach to Soil and Water Quality Management." National Research Council. 1993. Soil and Water Quality: An Agenda for Agriculture. Washington, DC: The National Academies Press. doi: 10.17226/2132.
×

FIGURE 3-3 Use of a geographic information system to target and direct soil and water quality programs. AGNPS, agriculture nonpoint source model; USLE, universal soil loss equation; EROPLAN, erosion planning model; MBMS, microcomputer budget management system; RMSs, resource management systems. Source: T. Prato, H. S. R. Rhew, and M. Brusuen. 1989. Soil erosion and nonpoint source pollution control in an Idaho watershed. Journal of Soil and Water Conservation 44:323-328. Reprinted with permission from © Journal of Soil and Water Conservation.

The Economic Research Service, the National Agricultural Statistics Service, and the Soil Conservation Service should assemble all currently available data on production practices and agronomic behaviors. This information, if assembled in one place, would be very helpful for the direction of policy. The effort to assemble these data would also be the first step toward identifying the gaps in current data collection that need to be filled.

Suggested Citation:"3 A Systems Approach to Soil and Water Quality Management." National Research Council. 1993. Soil and Water Quality: An Agenda for Agriculture. Washington, DC: The National Academies Press. doi: 10.17226/2132.
×

The Economic Research Service, the National Agricultural Statistics Service, and the Soil Conservation Service, in coordination with the Bureau of the Census, should develop, test, and implement ongoing surveys of production practices and agronomic behaviors.

The Economic Research Service and the National Agricultural Statistics Service are expanding current surveys of production practices. It is essential that such surveys continue over time to allow monitoring of changes in production practices. The value of production practice and agronomic behavioral data will be greatly enhanced if they can be linked to soil and water quality problems. The return on the current investment in data collection would be much greater if methods were developed to geographically link the data already collected in current and ongoing surveys. Such linkage should have as its goal improved policy formulation and implementation, particularly targeting.

The topographically integrated geographic encoding and referencing (TIGER) system, developed by the U.S. Bureau of the Census, could serve as a model for integrating agricultural census and farming system data with various land and water resource data bases. In addition, this spatial data base could contain information on factors such as the primary and secondary types of farming systems, the production activities that cause the most soil degradation or water pollution, the use of remedial production practices, and other factors that may influence the implementation of policies.

IMPLEMENTING A SYSTEMS APPROACH

USDA, EPA, and state and local programs provide important opportunities to implement a systems approach to preventing soil degradation and water pollution. These programs, however, will have to be restructured and redirected, in some cases, to implement a systems approach. Increasing the resistance of farming systems soils to erosion and runoff has historically been the overriding objective of USDA soil and water conservation programs. More emphasis is now being placed on protection of water quality in USDA programs. Tables 1-1 and 1-2 in Chapter 1 list the soil and water quality programs administered by the USDA, and the new initiatives passed as part of the 1990 Food, Agriculture, Conservation and Trade Act (PL 101-624). New USDA programs such as the Water Quality Incentives Program, the Wetland Reserve Program, and the Environmental Easement Program signal the increasing importance of water quality in USDA programs.

The EPA's programs are also increasingly affecting agriculture (see

Suggested Citation:"3 A Systems Approach to Soil and Water Quality Management." National Research Council. 1993. Soil and Water Quality: An Agenda for Agriculture. Washington, DC: The National Academies Press. doi: 10.17226/2132.
×

"Most important and least done about it" (February 6, 1936). Credit: Courtesy of the J.N. "Ding" Darling Foundation.

Suggested Citation:"3 A Systems Approach to Soil and Water Quality Management." National Research Council. 1993. Soil and Water Quality: An Agenda for Agriculture. Washington, DC: The National Academies Press. doi: 10.17226/2132.
×

Table 1-1). In 1990, states began implementing the management plans they were required to prepare under section 319 of the 1987 amendments to the Federal Water Pollution Control Act (PL 100-4) (U.S. Environmental Protection Agency, 1992). The 1990 Coastal Zone Management Act Reauthorization Amendments (PL 101-508) require states to develop nonpoint source control programs within the coastal zone. The state programs are required to include enforceable policies and mechanisms to implement pollution control practices, called management measures. Seven management measures—including erosion and sediment control, wastewater and runoff control from confined animal facilities, nutrient management, pesticide management, grazing management, and irrigation water management—will have direct effects on agricultural production in the coastal zone (U.S. Environmental Protection Agency, Office of Water, 1993).

State nonpoint source control programs, coastal zone programs, and the initiatives in the 1990 Food, Agricultural, Conservation, and Trade Act are important opportunities to address all four objectives proposed in this report: conserving and enhancing soil quality, improving input efficiency, increasing resistance to erosion and runoff, and making greater use of field and landscape buffer zones. Improved management of nutrients, pesticides, animal waste, or irrigation water is listed as an objective in all 16 demonstration projects and 74 hydrologic unit area projects that are part of USDA's Water Quality Initiative (U.S. Department of Agriculture, Working Group on Water Quality, 1991). These initiatives, along with the Water Quality Incentives Program represent a significant new commitment by the USDA to improve input management. Implementation of the management measures under 1990 Coastal Zone Act Reauthorization Amendments will also address the need to improve input management, and EPA's Office of Water (1982) reports that 24 percent of the management activities included in state nonpoint source pollution management plans address agricultural sources of pollution. The Wetland Reserve Program and the Environmental Easement Program created in the 1990 Food, Agriculture, Conservation and Trade Act are clear opportunities to make greater use of field and landscape buffer zones.

Limited Funding

Funding for these initiatives, however, has been limited. Significant new commitments of general revenues to agricultural soil and water quality programs have been made since 1985. Figure 3-4 shows that expenditures by USDA and related state and local programs have

Suggested Citation:"3 A Systems Approach to Soil and Water Quality Management." National Research Council. 1993. Soil and Water Quality: An Agenda for Agriculture. Washington, DC: The National Academies Press. doi: 10.17226/2132.
×

Figure 3-4 Conservation expenditures by the U.S. Department of Agriculture (USDA) and related state and local programs, 1983 to 1990. CRP, Conservation Reserve Program: Source: U.S. Department of Agriculture, Economic Research Service. 1990. Conservation and Water Quality. Pp. 28–41 in Agricultural Resources: Cropland, Water, and Conservation Situation and Outlook Report. Report No. AR-19. Washington, D.C.: U.S. Department of Agriculture.

increased 2.5-fold to more than $3.4 billion since 1986. Almost all of the increase in expenditures, however, was for the Conservation Reserve Program. Spending for other purposes increased much less.

In 1991, $51 million was provided by a grant through the EPA to help states implement plans to control nonpoint source pollution from all sources (U.S. Environmental Protection Agency, Office of Water, 1992). Only part of those funds were expended to control agricultural sources of pollution. The Agricultural Water Quality Protection Program was implemented under the Agricultural Conservation Program as a cost-shared practice called the Water Quality Incentives Program. The program is expected to expend $6.8 million in 1992 (U.S. Department of

Suggested Citation:"3 A Systems Approach to Soil and Water Quality Management." National Research Council. 1993. Soil and Water Quality: An Agenda for Agriculture. Washington, DC: The National Academies Press. doi: 10.17226/2132.
×

Agriculture, 1992). Expenditures for water quality incentives are about 3.5 percent of total Agricultural Conservation Program expenditures in 1992 and projected to be 8 percent in 1993. Limits on the amount of cost-share dollars that can be received by an individual producer participating in the Agricultural Conservation Program may, at times, be too low to cover a substantial share of the cost of adopting improved management practices. The Wetland Reserve Program was budgeted about $46 million expenditures in 1992 to enroll about 50,000 acres, and was budgeted for $160.9 million in fiscal year 1993 to enroll 381,000 acres (U.S. Department of Agriculture, 1992). Congress, however, failed to appropriate any funds in fiscal year 1993 for the Wetland Reserve Program. No funds have been budgeted for the Environmental Easement Program.

The historical emphasis on controlling erosion and runoff remains the focus of programs to control soil degradation and water pollution from agricultural production. In 1991, for example, 62 percent ($111.5 million) of the expenditures for cost-sharing the implementation of best-management practices in the Agricultural Conservation Program were for erosion control (U.S. Department of Agriculture, Agricultural Stabilization and Conservation Service, 1992). Seventeen percent ($30.5 million) of the cost-share expenditure was for water quality improvement, and about $15.9 million of cost-share expenditure for water quality was for one practice—agricultural waste control facilities (U.S. Department of Agriculture, Agricultural Conservation and Stabilization Service, 1992). Technical assistance provided by the Soil Conservation Service to producers is the single largest expenditure of federal funds for agricultural programs and totaled about $427 million in 1991 (U.S. Department of Agriculture, 1992). About 10 percent or $44 million of technical assistance was allocated to the implementation of the water quality initiative (U.S. Department of Agriculture, 1992). Most of the technical assistance provided by the Soil Conservation Service to producers since passage of the 1985 Food Security Act has been dedicated to helping producers determine whether their croplands are subject to Conservation Compliance, Sodbuster, or Swampbuster and to helping producers plan and implement conservation practices required under these programs (U.S. Department of Agriculture, 1992).

More money has been invested in the Conservation Reserve Program and the Wetland Reserve Program than all other conservation programs combined (U.S. Department of Agriculture, 1992). The Conservation Reserve Program was budgeted $1,642.1 million in 1992 to enroll another 1.1 million acres (U.S. Department of Agriculture, 1992).

Suggested Citation:"3 A Systems Approach to Soil and Water Quality Management." National Research Council. 1993. Soil and Water Quality: An Agenda for Agriculture. Washington, DC: The National Academies Press. doi: 10.17226/2132.
×
New Sources of Funds

Taxes on nutrient or pesticides inputs or reallocation of commodity program expenditures should be explored as ways to increase the funding available to support and sustain soil and water quality improvement programs over the long-term.

Substantial reallocation of existing funds or a significant new source of funds will be needed if current initiatives and programs are to comprehensively address soil quality, input efficiencies, resistance to erosion and runoff, and field and landscape buffer zones. Reallocation of existing funds to priority areas will help supply the funds required to undertake the more intensive and refined efforts needed to improve farming systems. New sources of funds, however, will be needed to sustain these efforts over the long-term. Relatively low taxes on nutrient and pesticide inputs or transfers of funds from commodity programs have the potential to generate large new sources of revenue.

Table 3-3 lists the 1992 expenditures for agricultural soil and water quality programs administered by USDA and EPA. Annual expenditures on technical assistance are less than 10 percent of annual expenditures for either pesticides or fertilizers on major commodity crops and 3 percent of Commodity Credit Corporation expenditures. All Agricultural Conservation Program expenditures for cost-sharing agreements with producers are about 3 percent of expenditures on either fertilizers or pesticides and about 1 percent of Commodity Credit Corporation expenditures. Expenditures for the Water Quality Incentives Program in 1992 represented only 0.1 percent of expenditures for either pesticides or fertilizers and 0.03 percent of Commodity Credit Corporation expenditures.

Special consideration should be given to revenue sources such as taxes on agricultural chemicals, fuel, heavy tractors, moldboard plows, irrigation water, and other inputs that can be related to soil and water quality degradation from agricultural production practices or to transfers from Commodity Credit Corporation programs to soil and water quality programs.

These sources should be explored as ways to generate the new funds needed to sustain soil and water quality programs. One percent ($128 million) of the annual 1990 expenditures of $12.8 billion on pesticides and fertilizers, for example, is more than 65 percent of the total 1992 expenditures on cost-sharing under the Agricultural Conservation Program, and more than 18 times the total 1992 expenditures on the Water Quality Incentive Program.

New sources of funds will be needed to implement and sustain efforts

Suggested Citation:"3 A Systems Approach to Soil and Water Quality Management." National Research Council. 1993. Soil and Water Quality: An Agenda for Agriculture. Washington, DC: The National Academies Press. doi: 10.17226/2132.
×

TABLE 3-3 Expenditures for Soil and Water Quality Programs as a Percentage of Expenditures on Pesticides, Synthetic Fertilizers, and Commodity Programs

 

Expenditures as Percentage of Spending on:

Program

Pesticidesa

Fertilizersa

Commodity Programsb

USDA programsb

Soil Conservation Service technical assistance

8.0

7.0

3.0

Agricultural Conservation Program

All Cost-Share Spending

3.0

3.0

1.0

Water Quality Incentive Program

0.1

0.1

0.03

Conservation Reserve Program

30.0

24.0

10.0

Wetland Reserve Program

0.8

0.6

0.3

EPA programsc

Nonpoint Program Grants

0.9

0.7

0.3

a The 1990 farm production expenditures for pesticides and for fertilizers and lime (pesticide, $5,727 million; fertilizers and lime, $7,137 million) were taken from U.S. Department of Agriculture, Economic Research Service and National Agricultural Statistics Service. 1992. Statistical indicators—farm income. Pp. 58–61 in Agricultural Outlook. Rockville, Md: U.S. Department of Agriculture.

b Estimated fiscal year 1992 expenditures in U.S. Department of Agriculture. 1992. 1993 Budget Summary. Washington, D.C.: U.S. Department of Agriculture. (Soil Conservation Service Technical Assistance, $478.0 million; Agricultural Conservation Program Cost-Share, $194.4 million; Water Quality Incentives Program, $6.8 million; Environmental Conservation Acreage Reserve Program, $1,786 million; Conservation Reserve Program, $1,740 million; Wetland Reserve Program, $46.4 million; commodity programs, Commodity Credit Corporation, $18,300 million).

c Fiscal year 1991 expenditures ($51 million) in U.S. Environmental Protection Agency. 1992. Managing Nonpoint Source Pollution: Final Report to Congress on Section 319 of the Clean Water Act (1989). Washington, D.C.: U.S. Environmental Protection Agency.

to protect soil and water quality. Soil and water quality programs may achieve greater continuity if they are funded through a mixture of both general revenues and new revenues generated by taxes on agricultural inputs.

Suggested Citation:"3 A Systems Approach to Soil and Water Quality Management." National Research Council. 1993. Soil and Water Quality: An Agenda for Agriculture. Washington, DC: The National Academies Press. doi: 10.17226/2132.
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How can the United States meet demands for agricultural production while solving the broader range of environmental problems attributed to farming practices? National policymakers who try to answer this question confront difficult trade-offs.

This book offers four specific strategies that can serve as the basis for a national policy to protect soil and water quality while maintaining U.S. agricultural productivity and competitiveness. Timely and comprehensive, the volume has important implications for the Clean Air Act and the 1995 farm bill.

Advocating a systems approach, the committee recommends specific farm practices and new approaches to prevention of soil degradation and water pollution for environmental agencies.

The volume details methods of evaluating soil management systems and offers a wealth of information on improved management of nitrogen, phosphorus, manure, pesticides, sediments, salt, and trace elements. Landscape analysis of nonpoint source pollution is also detailed.

Drawing together research findings, survey results, and case examples, the volume will be of interest to federal, state, and local policymakers; state and local environmental and agricultural officials and other environmental and agricultural specialists; scientists involved in soil and water issues; researchers; and agricultural producers.

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