Author
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Lu, Yao |
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Watkins, Kenton - Brad |
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Teasdale, John |
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Abdul Baki, Aref |
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Submitted to: Food Reviews International
Publication Type: Peer Reviewed Journal Publication Acceptance Date: 5/1/2000 Publication Date: N/A Citation: N/A Interpretive Summary: Most crops in Mid-Atlantic states are grown on fields with slopes and soil erosion is a major threat to long-term productivity on agricultural lands. Cover crops combined with reduced tillage could reduce soil erosion and increase profitability. The results of experiments at the Beltsville Agricultural Research Center on fresh-market tomato production indicated that tomatoes grown with hairy vetch mulch produced higher yields and higher profits than those grown with black polyethylene and no mulch. The results of comparative analysis of four reduced-tillage cropping systems at the Sustainable Agricultural Demonstration site indicated that the cover crop system produced the largest average gross margin while the manure system was the most environmentally sound. To evaluate the long-term economic and environmental impacts of incorporating cover crops into grain production systems in mid-Atlantic states, the EPIC model was used to simulate crop yields, pesticide losses, N and P losses, and soil erosion for five cropping systems over a 60-year period. Results indicated tradeoffs exist between competing objectives of increased profitability, reduced soil erosion, and reduced nutrient and pesticide losses into surface water and groundwater supplies. For example, when nitrogen was withheld from the cover crop system, nutrient hazard was reduced but so was profitability. The results will help farmers and extension agents select the most profitable cropping systems that are beneficial to the environment and to the natural resource base. Technical Abstract: Cover crops are an important component of sustainable agricultural practices. Combined with reduced tillage, they could reduce soil erosion, reduce need for inorganic nutrient amendments, improve soil organic content, increase soil water-holding capacity, control pests, reduce weed competition, and reduce need for herbicides. This paper evaluated the profitability and economic risk of sustainable grain and vegetable production using cover crops at the Beltsville Agriculture Research Center in Maryland. Results of experiments on fresh-market tomato production indicated that tomatoes grown with hairy vetch mulch were higher yielding and more profitable than those grown with black polyethylene and no mulch systems. A comparative analysis of four reduced-tillage corn based cropping systems at the Sustainable Agricultural Demonstration site indicated that the cover crop system with corn following hairy vetch produced the largest average gross margin. We also used the EPIC model to simulate the long-term economic and environmental impacts of incorporating cover crops into grain production systems. Results based on a 60-year simulation showed that tradeoffs existed between the competing objectives of increased profitability, lower soil erosion, and reduced nutrient and pesticide hazards to surface and groundwater supplies. A corn/soybean two-year rotation was found to be the most profitable, while the cover crop system and the manure system were found to be the most environmentally sound. Interpretative summary |
