Submitted to: Agronomy Abstracts
Publication Type: Abstract Only
Publication Acceptance Date: October 21, 2001
Publication Date: N/A
Technical Abstract: The USDA-ARS Farming Systems Project is a long-term cropping systems study designed to evaluate the sustainability of regionally-appropriate cropping systems. Seven replicated cropping systems were established in 1996. One of the systems is a synthetic no-till rotation, three of the systems are conventional till rotations with different fertility sources, and three of the systems are organic with different crop rotation lengths. In the summer of 2000, we made an initial assessment of soil quality in the synthetic no-till, one of the synthetic till (conventional fertilizer) and one of the organic cropping systems. The synthetic systems had 2-year, corn-wheat-soybean crop rotations. The organic system had a corn-soybean- wheat rotation with cover crops managed using reduced tillage techniques and with small amounts of broiler litter applied. After five years, the soil in the organic cropping system had greater total carbon and nitrogen, particulate organic matter, water-stable soil aggregates, glomalin, and humic and fulvic acids, and a larger active carbon pool than the synthetic systems. We are currently assessing whether improved soil quality using organic management is due to the use of cover crops or broiler litter by evaluating soil samples taken from the conventional till cropping systems that received broiler litter but no cover crops.