Submitted to: Meeting Abstract
Publication Type: Abstract Only
Publication Acceptance Date: 10/21/1998
Publication Date: N/A
Technical Abstract: No-tillage management reduces soil disturbance and, therefore, may improve soil organic matter, aggregation and hydraulic properties leading to enhanced soil quality and sustained crop production. We determined changes in soil aggregation, soil organic carbon (SOC), carbohydrates, soil microbial biomass (SMBC) and moisture retention in a loam and silt loam soil (Luvisols) managed for 8-16 yr under conventional (CT) and no-tillage (NT). No-tillage under continuous spring cropping resulted in a significant improvement in surface soil structure, water storage, organic matter, and total carbohydrates. Improvement of total soil organic C under NT compared with CT occurred only near the soil surface. Water-stable aggregation improved under NT compared with CT with more soil organic C sequestered within macroaggregates that helped to stabilize these aggregates. Water-stable macroaggregates (> 0.25 mm) and aggregate mean weight diameter were greater under NT throughout the growing season than under CT. Concentration of SOC and SMBC tended to be greatest in macroaggregates and lowest in microaggregates (<0.25 mm). Our results suggest that long-term NT can significantly improve soil structure, and potentially increase SOC sequestration and enhance soil quality.