|Paudel, Bodh -|
|Udawatta, Ranjith -|
|Anderson, Stephen -|
Submitted to: Agroforestry Systems
Publication Type: Abstract Only
Publication Acceptance Date: May 10, 2011
Publication Date: June 4, 2011
Citation: Paudel, B., Udawatta, R., Anderson, S.H., Kremer, R.J. 2011. Soil quality parameters for row-crop and grazed pasture systems with agroforestry buffers. In: Proceedings of 12th Annual North American Agroforestry Conference, June 4-9, 2011, Athens, Georgia. 2011 CDROM. Technical Abstract: Incorporation of trees and establishment of buffers are practices that can improve soil quality. Soil enzyme activities and water stable aggregates are sensitive indices for assessing soil quality by detecting early changes in soil management. However, studies comparing grazed pasture and row crop systems using these indices are limited. The objective of this study is to examine the activities of selected enzymes (fluorescein diacetate [FDA] hydrolase, dehydrogenase, ß-glucosidase and ß-glucosaminidase), aggregate stability (as water-stable aggregates [WSA]), and soil organic carbon and total nitrogen as soil quality indices for grazed pasture and row-crop systems. The study consisted of four management treatments: grazed pasture, agroforestry buffer, grass buffer, and row-crop systems. Two soil depths (0-10 and 10-20 cm) were analyzed for all treatments over two years (2009 and 2010). The row-crop treatment exhibited significantly lower (P less than 0.05) ß-glucosidase and ß-glucosaminidase activities and WSA values compared to all other treatments. FDA hydrolase activity was significantly lower (P less than 0.05) in the row crop system only in 2010. Surface soil revealed higher enzyme activities and higher WSA than the sub-surface soil. The treatment by depth interactions were significant (P less than 0.05) for ß-glucosidase and ß-glucosaminidase activities in 2009 and for dehydrogenase and ß-glucosaminidase activities in 2010. Permanent vegetation in grass buffers and grazed pasture may improve soil quality by enhancing microbial activity, indicated by soil enzymatic activity and aggregate stability, which appear to be effective indicators for detecting soil quality responses to diverse management practices including grazed pastures and agroforestry buffers.