ARS | Publication request: WHAT GOVERNS THE CONVERSION OF RESIDUE TO ORGANIC MATTER?

Submitted to: Soil Science Society of America Annual Meeting
Publication Type: Abstract Only
Publication Acceptance Date: October 2, 2003
Publication Date: November 2, 2003
Citation: Pikul Jr, J.L., Johnson, J.M. 2003. What governs the conversion of residue to organic matter?[CD-ROM]. ASA-CSSA-SSSA Annual Meeting Abstracts. Madison, Wisconsin.

Technical Abstract: Soil organic matter (SOM) has important beneficial properties related to soil nutrient availability and soil physical behavior. The state of the soil physical environment is important for maintaining sustained agronomic production, a concept embodied in the presumption that good soil tilth is a precursor to high crop productivity. Interaction between crop and soil management practices and soil condition are often clouded by variability within a system. Of the factors that control the quantity of SOM in agricultural soils, only crop rotation, residue management, and tillage are under control of the land manager. Causal relationships between management and SOM are difficult to extrapolate from one region to another because of differences in soil type, climate, and management norms. The focus of this paper is to ascertain what governs the conversion of crop residue to SOM. The authors provide a review of some important long-term field experiments in North America to illustrate effect of management on quantity of SOM. Soil organic matter levels have decreased in many agricultural soils during the past 100 years and the question remains as to the length of time required to rebuild SOM, or whether rebuilding SOM is feasible under intensive agricultural production.