Submitted to: Meeting Abstract
Publication Type: Abstract Only
Publication Acceptance Date: 10/18/2004
Publication Date: 2/12/2005
Citation: Jung, W., Kitchen, N.R. 2005. Cropping management impacts soil quality indicators for claypan soils [abstract]. 2005 Missouri Natural Resources Conference. February 2, 2005. Lake of the Ozarks, MO.
Technical Abstract: Management practices have the potential to either enhance or degrade soil quality, which in turn impact crop production and the environment. The objectives of this study were to investigate how 13 years of cropping and conservation reserve program (CRP) practices have impacted soil quality indicators for a claypan soil. Soil cores (5.2 cm diameter by 0-7.5 cm, 7.5-15 cm, and 15-30 cm depth) and other in-field measurements were collected from three cropping management systems and one CRP system: (1) minimum-tillage management of a corn (Zea mays L.)-soybean [Glycine max (L.) Merr.] rotation with high agrichemical input (CS1); (2) no-tillage, corn-soybean rotation with high agrichemical input (CS2); (3) no-tillage corn-soybean-wheat (Triticum aestivum L.)-cover crop rotation with reduced agrichemical input (CS3); and (4) continuous cool-season grass and legume with no agrichemical input (CRP). Soil aggregation stability at all three sampling depths was about 40% higher in no-till management systems than on CS1. CRP management more than doubled soil aggregation of the three grain cropping systems. At the shallow sampling depths, no-tillage (CS2 and CS3) increased soil bulk density above that of CS1. The water infiltration rate was higher with CS1 than with CS2 and CS3. At the 0- to 7.5-cm depth, CRP increased soil organic carbon storage by 33% and soil total nitrogen storage by 34%. This study suggests that soil quality, as measured by these indicators, is greatly improved on a claypan soil when managed as CRP. We theorize that the primary reason for this difference comes from growing perennial plants that partition more carbon below ground than do annual grain crops.