Assessing Soil Quality of Alternative and Conventional Cropping Systems in SW Minnesota.
(S04-kuratomi865683-oral)
Authors:
M. Kuratomi* - Univ. of Minnesota D.L. Allan - Univ. of Minnesota E. Dyck - Univ. of Minnesota
Abstract:
Crop rotations, tillage intensity and added inputs work together in cropping systems to maintain or degrade soil quality and determine sustainability. This study compared soil quality differences in the 14-year old Variable Input Crop Management Study (VICMS) in Lamberton, MN. VICMS consists of two sites, initially high and low fertility, managed in two crop rotations (2-yr corn-soybean and 4-yr corn-soybean-oat/alfalfa-alfalfa) under four management strategies (minimum inputs (MIN), low purchased inputs (LPI), high purchased inputs (HPI), and organic (ORG)). Soil quality indicators measured included aggregate stability, microbial biomass, mineralizable and total C and N, particulate organic matter, pH and available macronutrients, with bulk density and infiltration rate measured on a subset of plots. Overall, LPI and ORG had the highest soil quality ratings. For the 2-yr rotation, macroaggregates were 25-35% higher in LPI compared to the other management systems, because of reduced tillage intensity. Most measures of labile C and N were higher in ORG compared to other management systems as a result of manure additions. The 2-yr HPI, representing the vast majority of acreage in SW Minnesota, had the lowest soil quality. The 4-yr rotation was less variable and generally had higher soil quality than the 2-yr rotation, due to the soil-improving effects of oats and alfalfa.
Speaker Information: Maya Kuratomi, Univ. of Minnesota, 1991 Upper Buford Circle439 Borlaug Hall, St Paul, MN 551088; Phone: 612-625-3717; E-mail: [email protected]
Session Information: Wednesday, November 5, 2003, 12:55 PM-4:00 PM Presentation Start: 3:15 PM