Title: Enzyme Activities as Sensitive Indicators of Changes in Soil Metabolic Functioning in Alternative Management for Continuous Cotton Authors
|Allen, Vivien -|
|Wester, David -|
Submitted to: Meeting Abstract
Publication Type: Abstract Only
Publication Acceptance Date: July 17, 2011
Publication Date: July 21, 2011
Citation: Acosta Martinez, V., Zobeck, T.M., Lascano, R.J., Upchurch, D.R., Allen, V., Wester, D. 2011. Enzyme Activities as Sensitive Indicators of Changes in Soil Metabolic Functioning in Alternative Management for Continuous Cotton[abstract]. Enzymes in the Environment. July 17-21, 2011, Bad Nauheim, Germany. Technical Abstract: Cotton production practices in the Texas High Plains (THP) region have involved monocultures, heavy irrigation, and conventional tillage since 1940, which must have contributed to the soil erosion and degradation observed in soils. Within the past 10 years, alternative cotton cropping management practices have been suggested to endorse reduced tillage, incorporate rotations of cotton with drought tolerant (i.e., sorghum) and legume (i.e., peanut) crops and integrating livestock as a source of organic soil carbon inputs. To determine the overall effectiveness of these alternative management practices, soil enzyme activities must be evaluated because they facilitate metabolic functioning processes such as nutrient cycling and soil organic matter changes. Analyses of soil enzyme activities are relatively inexpensive compared to other biochemical analyses. Our research team evaluated soil enzyme activities involved in C-cycling ( ß-glucosidase and a-galactosidase), N-cycling (L-glutaminase, L-aspartase, ß-glucosaminidase, arylamidase), S-cycling (arylsulfatase) and P-cycling (acid phosphatase, alkaline phosphatase, and phosphodiesterase) contrasted across several different land use and management practices (i.e., Conservation Reserve Program, crop rotations, livestock-crop integrated systems, and continuous cotton) in representative semiarid soils in the THP over a 10 year period. Our research has identified how long it takes for different management practices to impact soil enzyme activities of C, N, P and S cycling compared to continuous cotton depending on the crop used; and enzyme activities have always anticipated changes in other soil properties within the first 10 years of management. Our research in this region demonstrates that enzyme activities should be evaluated in soil quality assessments in order to better understand soil ecosystem function. Different approaches have been used to evaluate changes in enzyme activities, their relationship to other soil properties and to establish their linkages with microbial communities associated to the enzymes activities.