Submitted to: ASA-CSSA-SSSA Annual Meeting Abstracts
Publication Type: Abstract Only
Publication Acceptance Date: 10/30/2019
Publication Date: 11/10/2019
Citation: Veum, K.S., Kitchen, N.R., Sudduth, K.A. 2019. Soil health after 25 years of conservation management [abstract]. ASA-CSSA-SSA Annual International Conference, November 10-13, 2019, San Antonio, Texas. No. 1514.
Technical Abstract: The Salt River Basin in northeastern Missouri, USA is part of the Central Mississippi River Basin (CMRB) Long-Term Agroecosystem Research (LTAR) network operated by USDA-ARS, and is located in the heart of the Central Claypan Region, designated as Major Land Resource Area 113. In this region, subsurface soil horizons with 45 to 65% clay reduce water in'ltration and impede root growth. Due to the sensitivity of this ecosystem, monitoring and assessment of soil health is critical. The objectives of this study were (1) to compare soil health after 25 years of continuous management under 12 different perennial vegetation and annual cropping systems typically employed in this region, (2) to evaluate the sensitivity and utility of multiple soil health indicators across these management systems, and (3) to examine relationships among multiple soil health indicators. Annual cropping systems included corn-soybean rotations with variable tillage and cover crop management. Perennial vegetation systems included permanent cool- and warm-season grasses and working grasslands (i.e., hay production). Soil samples were obtained in 2016 from the surface (0-5 cm) and subsurface (5-15 cm) layers. Multiple biological, physical, and chemical soil health indicators were measured, including phospholipid fatty acid profiles for microbial community structure, total organic carbon and nitrogen, ß-glucosidase and ß-glucosaminidase enzyme activities, total protein, respiration, mineralizable nitrogen, active carbon, pH, extractable P and K, bulk density, aggregate stability, and particle size. Soil health was further quantified using the Soil Management Assessment Framework (SMAF) to provide an integrated, comprehensive assessment by using scoring algorithms based on site-specific characteristics. Results of this study are expected to demonstrate the strong influence of vegetative cover and living roots on surface soil health, and emphasize the importance of diversified cropping systems that reduce soil disturbance and maximize soil cover.