Paper presented at the 12th North American Agroforesty Conference, which was held June 4-9, 2011 in Athens, Georgia.In Ashton, S. F., S.W. Workman, W.G. Hubbard and D.J. Moorhead, eds. Agroforestry: A Profitable Land Use. Proceedings, 12th North American Agroforestry Conference, Athens, GA, June 4-9, 2011.Incorporation of trees and establishment of buffer are believed to enhance soil quality. Soil enzyme activities and water stable aggregates have been identified as good indices for assessing soil quality to evaluate early responses to changes in soil management. However, studies comparing these parameters for grazing pastures and row crop systems are limited. The objective of this study is to examine the activities of selected enzymes (fluorescein diacetate (FDA) hydrolase, dehydrogenase, [beta]-glucosidase and [beta]-glucosaminidase), the percentage of water stable aggregates (WSA), and soil organic carbon and nitrogen as soil quality parameters for grazed pasture and row-crop systems. The study consisted of four management treatments: grazed pasture (GP), agroforestry buffer (AgB), grass buffer (GB) and row-crop (RC). Soil organic carbon (SOC), total nitrogen (TN) contents and soil bulk density were also determined. Two soil depths (0-10 and 10-20 cm) were analyzed for all treatments for two consecutive years, 2009 and 2010. The row-crop treatment showed significantly lower [beta]-glucosidase and [beta]-glucosaminidase activity and significantly lower WSA compared to all other treatments. The FDA hydrolase activities were not significant in 2009 but were significant in 2010. There were numerical variations of parameters in two years but the pattern was consistent. Surface soil revealed higher enzyme activities and higher WSA than the sub-surface soil. The treatment by depth interactions were significant for [beta]-glucosidase and [beta]-glucosaminidase enzymes in 2009 but the interactions were significant for dehydrogenase and [beta]-glucosaminidase enzymes in 2010. Implications can be made that permanent vegetation will improve soil quality by enhancing organic matter accumulation in the soil and increasing microbial activity with minimum soil disturbance which will have a positive effect on the ecosystems.Bodh Paudel (1), Ranjith Udawatta (1,2), Stephen H. Anderson (1) and Robert Kremer (3) ; 1. Soil, Environmental and Atmospheric Sciences, 302 Anheuser-Busch Natural Resources Building, University of Missouri, Columbia, MO, USA. 2. Center for Agroforestry, 203 Anheuser-Busch Natural Resources Building, University of Missouri, Columbia, MO, USA. 3. USDA-ARS Cropping Systems and Water Quality Unit, University of Missouri, Columbia, MO, USA.Includes bibliographical references
