ARS | Publication request: SOIL PHYSICAL CHARACTERISTICS OF CONTRASTING CROPPING SYSTEMS IN THE GREAT PLAINS: PRELIMINARY FINDINGS

Submitted to: Dynamic Cropping Systems: Principles, Processes and Challenges
Publication Type: Proceedings
Publication Acceptance Date: June 6, 2003
Publication Date: August 4, 2003
Citation: PIKUL JR, J.L., SCHWARTZ, R.C., BENJAMIN, J.G., BAUMHARDT, R.L., MERRILL, S.D. SOIL PHYSICAL CHARACTERISTICS OF CONTRASTING CROPPING SYSTEMS IN THE GREAT PLAINS: PRELIMINARY FINDINGS. DYNAMIC CROPPING SYSTEMS: PRINCIPLES, PROCESSES AND CHALLENGES. 2003. p. 205-209.

Interpretive Summary: 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. Agricultural systems may produce both damaging and beneficial effects on soil physical condition. Little is known about the long-term interaction of crop systems, residue and fertilizer management on soil physical condition. Soil organic matter is linked to fertility and a desirable soil physical state and often has a disproportionate effect on soil physical behavior. Maintenance of soil organic matter seems to be the key to sustaining the soil resource and crop productivity. A multi-location study was conducted during 1999 to 2002 to evaluate a number of physical, chemical, and biological properties associated with assessment of soil quality. The purpose of this report is to present preliminary findings on selected soil physical attributes. We identified no significant cropping system effect on water infiltration for locations having the same tillage operations within the cropping system. Mean weight diameter of soil aggregates (an index of soil aggregate stability) was affected by cropping intensity and tillage. Systems without fallow or systems with reduced tillage had a larger mean weight diameter than systems having fallow or tillage. Tillage resulted in increased, decreased, or unchanged BD near the soil surface, when compared with no tillage, depending on time of year. Measurements of infiltration, mean weight diameter, or soil bulk density made at only one time in a rotation cycle do not convey meaningful information on soil quality because of significant temporal variation in these properties.

Technical Abstract: Agricultural systems may produce both damaging and beneficial effects on soil physical condition. We conducted a multi-location study during 1999 to 2002 to evaluate physical, chemical, and biological attributes of soil quality. Our hypothesis was that increased diversity of cropping system improves soil quality attributes. This report provides preliminary findings of cropping systems effects on water infiltration, aggregate size distribution (expressed as mean weight diameter, MWD), and bulk density (BD). We identified no significant cropping system effect on water infiltration for locations having the same tillage operations within the cropping system. MWD was significantly greater at Bushland and Fargo; locations that have different cropping intensity or no tillage. Tillage resulted in increased, decreased, or unchanged BD near the soil surface, when compared with no tillage, depending on time of year. Measurements of infiltration, MWD, or BD made at only one time in a rotation cycle do not convey meaningful information on soil quality because of significant temporal variation in these properties.