Environmental, Energetic, and Economic Comparisons of Organic and Conventional Farming Systems

This article explains the sustainable benefits to organic farming."The estimated environmental and health care costs of pesticide use at recommended levels and health care costs of pesticide use at recommended levels in the United States run about $12 billion every year." This is mostly attributed to runoff from ground water in lakes and streams used for irrigation as well as drinking water. Because of the health and environmental concerns attributed to pesticide use on cropland there has been a push toward pesticide free farming or organic farming. "The aim of organic agriculture is to augment ecological processes that foster plant nutrition yet conserve soil and water resources. Organic systems eliminate agrochemicals and reduce other external inputs to improve the environment and farm economics."
"From 1981 through 2002, field investigations were conducted at the Rodale Institute FST in Kutztown, Pennsylvania, on 6.1 ha. The soil at the study site is a moderately well-drained Comly silt loam. The growing climate is sub humid temperature." The field was divided into three equal plots one with "The conventional cropping system", based on synthetic fertilizer and herbicide use, represented a typical cash grain, row crop farming unit and used simple 5-year crop rotation (corn, corn, soybeans, corn, soybeans) that reflects commercial conventional operations in the regions throughout the Midwest." Another third was organic "animal-based cropping". "This system represented a typical livestock operation in which grain crops were grown for animal feed not cash sale... Aged cattle manure served as nitrogen source and was applied at a rate of 5.6 metric tons (t) per ha (dry), 2 years out of every 5, immediately before plowing soil for corn." The third and last plot consisted of "organic legume-based cropping". "This system represented a cash grain operation, without livestock. Like the conventional system, it produced a cash grain crop every year; however, it used no commercial synthetic fertilizers, relying instead on nitrogen-fixing green manure crops as a nitrogen source." The results showed a greater amount of carbon retention within the soil in organic methods than conventional. Less fossil fuel was also used during organic farming then conventional. "Except for the 1999 drought year, the crop yields for corn and soybeans were similar in the organic animal, organic legume, and conventional farming systems." "Two primary problems with the organic system... were nitrogen deficiency and weed competition." The nitrogen deficiency was solved with legume crop cover and because organic farming is limited to biological and mechanical deterrents pest control must be handled based on geographic location. The article describes that organic farming not only provides a sustainable solution but a beneficial one as well "although labor inputs average about 15% higher in organic farming systems (ranging from 7% to 75% higher), they are more evenly distributed over the year in organic farming systems then in conventional farming systems."

Citations:
Environmental, Energetic, and Economic Comparisons of Organic and Conventional Farming Systems.
by: David Pimentel et al.

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