Elements of sustainable agriculture

A nearly infinite number of dimensions must be considered if productivity o f an agroecosystem is to be sustained indefinitely. In many cases, the most limiting element may determine the future sustainability of the system and set the context in which management decisions, including those involving n ematodes, must be made. Some examples of critical elements that may change over time include human population size, water, fossil fuel energy, nitroge n, carbon dioxide. salinity, economics, and amount of cropland. The implica tions of these factors in future nematode management strategies are discuss ed briefly. The multiple dimensions affecting the sustainability of an agro ecosystem parallel the dimensions of the ecological niches of the organisms involved, but include a number of human-imposed dimensions (political, soc ial, economic, and management practices) as well. A variety of complex prob lems, some with conflicting solutions, must be addressed in the planning an d design of agroecosystems sustainable for future generations.