A conceptual model and indicators for assessing the ecological condition of agricultural lands

As part of an environmental monitoring and assessment effort, we developed a conceptual model for measuring and assessing the condition and sustainabi lity of agroecosystems. An agroecosystem is a field, pasture, or orchard an d the associated border areas. We focused on ecological sustainability and defined the goals for agroecosystems in terms of the values people place on them. The purpose of an agroecosystem is to produce food and fiber. Other desired outcomes can be considered as goals for the larger landscape and th e rest of the world, and they sometimes function as constraints on producti on. Condition is defined by agroecosystem productivity and the degree to wh ich farmers use management and stewardship practices that conserve and prot ect valued natural resources in the landscape and the rest of the world. An agoecosystem in good condition is productive and is managed to conserve va lued resources. Sustainability is the maintenance of good condition over ti me. We developed indicators that link system condition and sustainability t o societal values and goals. These indicators measure productivity, managem ent practices that promote sustainability at the agroecosystem scale, and m anagement practices that promote sustainability at landscape and global sca les. Our initial efforts focused on annually harvested herbaceous crops; ho wever, the concepts we used can be adapted to other plant and livestock sys tems. Our conceptual approach may be used to evaluate the effectiveness of several major programs now being implemented, including the USDA's Environm ental Quality Incentive and Conservation Reserve Programs.