Assessment of Conservation Benefits Derived from Conservation Practices in the United States

摘要

The United States Department of Agriculture (USDA) is quantifying the environmental benefits from implementing conservation practices used by private landowners across the United States. The Conservation Effects Assessment Project (CEAP) will assess conservation practices including conservation buffers, erosion control, wetland construction and restoration, establishment of wildlife habitat, management of grazing lands, tillage, nutrient and pest management, and irrigation and drainage water measures. CEAP is focusing on developing approaches, methodologies, and databases that produce scientifically credible estimates of environmental benefits of applying conservation. The initial data comes from direct landowner surveys on historic natural resourceinventory (NRI) points that have been a part of USDA conservation assessment for nearly thirty years. These NRI points provide the statistical frame for the model computations. An area sample frame is used to capture the diversity of the resource base (climate, soils, landscape). USDA developed a farmer survey to collect the field-level information to model and assess the effects of conservation practices. Included in the direct landowner survey (nearly 20,000 NRI points) are data gathering questions that depicts the land management (tillage, cropping, agrichemical applications). By micro-simulation modelling using a combination of historic NRI information, farmer surveys, and physical computer process modelling (EPIC/APEX/SWAT) we are able to statistically account for environmental benefits that have been derived, and in the future could be derived, by establishing specific conservation measures. From these assessments USDA will be better prepared to develop future conservation programs that answerthe questions about quantifiable benefits and economical efficiency of implementing certain conservation practices to solve specific conservation resource concerns and meet the USA environmental and resource goals. The ultimate goal of CEAP is to reportbenefits in terms of recognizable outcomes such as cleaner water, more efficient use of irrigation water, and changes in soil quality that will result in more sustainable and profitable production over time. The current primary focus is on water qualityand quantity and soil quality. Results from the first two years of survey data analyses will be presented. What are the most effective interventions — conservation practices, alternative farming systems, land use changes, or hydrologic restorations - toachieve specific environmental benefits? Where such interventions should be placed on the landscape? How can we evaluate and monitor the conservation benefits in terms of cleaner, more abundant water and soil health?