|Arshad, M - AGRI & AGRI-FOOD, CANADA|
|Azooz, R - AGRI & AGRI-FOOD, CANADA|
Submitted to: Soil & Tillage Research
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: May 19, 2003
Publication Date: November 14, 2003
Citation: Arshad, M.A., Franzluebbers, A.J., Azooz, R.H. Surface-soil structural properties under grass and cereal production on a mollic cryoboralf in canada. International Journal of Soil and Tillage Research. 2003. v. 77. p. 15-23. Interpretive Summary: Degradation of soil and water resources with cropping can be a perceived and real problem throughout the world. We evaluated soil indicators of erosion resistance, soil fertility, and biophysical complexity under permanent grass cover and under 3-year wheat crop rotations under no-tillage management. Researchers at Agriculture and Agri-Food Canada in Beaverlodge AB led an 11-year-long evaluation of these systems with soil evaluation expertise from a researcher at the USDA-Agricultural Research Service in Watkinsville GA. Many soil properties were in better condition at the end of 11 years under permanent grass cover than under wheat cropping systems. However, differences were not extremely large, as would typically be observed had the wheat been cultivated with conventional inversion tillage rather than with no tillage. High cereal roduction was achieved without significantly reducing soil quality in wheat cropping systems without fallow. These results suggest two economically viable production alternatives for producers (hay harvest and grain production with no tillage) that would save millions of dollars to tax payers and nature enthusiasts by avoiding environmental degradation of the landscape and its receiving surface waters.
Technical Abstract: Conservation tillage has become a major soil management strategy to reduce soil erosion and improve soil quality, yet the impacts of how crop rotation might alter soil responses to conservation tillage remain poorly described. We compared the effect of perennial grass cover versus annual cropping systems and the effect of the type of break crop in a wheat-based crop rotation system on surface-soil (0-10 cm) structural properties at the end of 10 and 11 years of management. Soil aggregation was at state to resist water erosion more under perennial grass than under annual cropping systems. Soil organic C was higher, but total soil N was lower under perennial compared with annual cropping systems. There were few significant differences in soil-structural properties among the various annual cropping systems, the largest being greater light-fraction C and N under continuous wheat compared with other rotations as a result of higher residue inputs. Despite somewhat lower quality of soil with annual than with perennial cropping systems, high productivity of cereal production can be achieved without dramatic detriment to the soil and the surrounding environment using conservation tillage management without bare fallow.