Redistribution of crop residues during row cultivation creates a biologically enhanced environment for soil microorganisms

Authors

M. Susana Grigera, University of Nebraska-Lincoln
Rhae A. Drijber, University of Nebraska-LincolnFollow
Brian J. Wienhold, University of Nebraska-LincolnFollow

Date of this Version

5-1-2007

Comments

Published in Soil & Tillage Research 94 (2007) 550–554. Copyright 2006 Elsevier B.V. Used by permission.

Abstract

Formation of ridges during row cultivation creates microsites that could enhance spatial heterogeneity of soil properties, such as organic C, and thereby influence soil microbial communities. A study was conducted during 2003 near Shelton, NE, on a corn (Zea mays L.) field mapped using apparent electrical conductivity (ECa). New ridges were built each year with a row cultivator when corn reached the V3–V4 growth stage. Cultivation increased labile C fractions and soil microbial biomass in the row position for all ECa classes. Canonical discrimination analysis showed no clear differences in relative abundance of specific microbial groups among ECa classes or between row and furrow position, except for enhanced mycorrhizal biomass in the row. Microbial biomass responded strongly to changes in C redistribution, but was not accompanied by a significant change in the abundance of specific microbial groups. Labile C fractions (coarse and fine particulate organic matter) and crop residues in diverse stages of decomposition are associated with diverse microbial groups. Thus, row cultivation for weed control creates a biologically enhanced root zone that may improve early season performance of corn.