Living Systems


Sustainable Agricultural Production

Technical Applications

Summary

Sustainable agricultural systems address the development of environmentally sound, productive, economically viable and socially desirable agriculture. The stability and sustained fertility of the soil depend on prevailing soil-climate conditions and on the effects of human activity.

Characteristics

There are strict limits to the extent of human influence over soil substrates, ground, soil and surface water, and the resident flora, fauna and micro-organisms which are essential to productive agriculture. The preservation of arable land must continually meet the challenges of desertification, deforestation, salinization, soil degradation and soil erosion. Regional and global climate change also has the potential to alter the productivity and suitability of many crop systems.

ImpactEconomy

Selective breeding to enhance desirable attributes has been a long-standing hallmark of agricultural R&D. Biotechnology and genetic engineering are facilitating the manipulation of seed stock to create food and fiber crops with selectively enhanced attributes such as drought tolerance or pest resistance. Cereal grains such as wheat and rice are being intensively studied, with traits such as growth cycle, disease resistance and stalk height already well known. Efforts are well underway to improve their resistance to fungal, bacterial, and viral diseases, as well as insects, drought and increased salinity. The preservation of wild seed grain is of continuing importance. Many crops have become highly specialized, whether to enhance crop yield, flavor, or shelf life, but in the process may have become more vulnerable to drought or specific pests or disease. It has frequently proven invaluable to return to historic wild seed to study the basic attributes which may have been "bred-out" in the pursuit of more economically attractive strains. That the resulting monocultures showed reduced tolerance in not problematic under narrowly defined conditions, but when environmental conditions shift significantly (as in the drought experienced in the Midwest in the 1970s and the subsequent corn blight) they can be highly vulnerable. Thus the importance of ancestral seed collections as a "reference resource."

WorldView

Through efforts of the USDA and various land-grant university Departments of Agriculture, the U.S. investment in this area is substantially greater than that of other nations. The published work from Germany and the Netherlands is oriented to production in semi-arid regions such as West Africa. The globally dominant position of the United States in worldwide food production is reflected in the research in this area.