Submitted to: Electronic Publication
Publication Type: Other
Publication Acceptance Date: 8/20/2010
Publication Date: N/A
Interpretive Summary: Agricultural pollution by nutrients is a serious concern. A scientist with the USDA Agricultural Research Service in Watkinsville Georgia assembled an evaluation of the sources and causes of nitrogen loss to the environment in agricultural systems for the Encyclopedia of Environmental Management. High input of N in the current industrialized model of agricultural production often leaves behind a significant amount of inorganic nitrogen, such that loss from leaching, runoff, volatilization, and denitrification can occur. Ecologically based strategies of agricultural production recognize the importance of having sufficient nitrogen for production, but rely on biological cycling among plants, animals, and soil microorganisms and fauna to synchronize the release of organically bound nitrogen into inorganic forms and avoid environmental pollution. Ecological principles of high biological diversity, continuous plant growth and soil cover, and limited soil disturbance can be used in many different climatic and ecological conditions to avoid environmental pollution by excessive nitrogen entering water bodies and air systems. This reference book will give quick access to a description of all pollution problems, their sources and their solutions.
Technical Abstract: Carbon and nitrogen are two key elements of global significance, playing large roles in the production of food, feed, fiber, and fuel for human existence, as well as providing numerous other ecosystem services. Although nitrogen is often a limiting element in natural systems, it can become a polluting element as a by-product of agricultural management due to the many pathways for it to be lost from the point of application (high input of nitrogen fertilizers has occurred during the last half century to achieve high production goals). Nitrogen loss from leaching, runoff, volatilization, and denitrification can pollute water and air resources. The conundrum of agriculture is to get enough of nitrogen without releasing it to the environment. Continuous biological cycling of carbon and nitrogen with conservation or ecologically based agricultural approaches can significantly reduce the environmental pollution with nitrogen. Limiting the time that inorganic nitrogen is present in soil will limit its loss, and this can be achieved by limiting soil disturbance, maintaining continuous plant and residue cover on soil, and creating a diversified cropping system to balance ecological stability.