Background/Question/Methods                                                                                                                                                                                

Water and nutrient availability are significant factors limiting agricultural production in semiarid regions including the Texas High Plains.  Efforts to sustain cotton and peanut production in this region have focused on integrating alternate tillage management practices within cotton systems in order to maintain soil health by reducing erosion and irrigation needs, while maximizing soil microbial contributions. Soil microbial functionality with respect to extracellular enzyme activities can have strong impacts on belowground nutrient cycling. Previous research efforts have demonstrated soil enzyme activity positively correlated with soil fertility.  It is important to understand how differing agricultural practices impact soil functionality. In this study, β-glucoaminidase, β-glucosidase, α-galactosidase, phosphodiesterase, and alkaline phosphatase measured to assess soil microbial functional responses to varying tillage and irrigation over different seasons.

Results/Conclusions

Our results suggest that overall, differing seasonal tillage practices had no effect on soil microbial functional diversity with respect to exoenzyme activities of , β-glucoaminidase , α-galactosidase, phosphodiesterase, and alkaline phosphatase.  Conversely, β-glucosidase activity demonstrated a slight response to tillage practies, demonstrating increased activity in response to strip tillage when compared to conventional tillage practices. This may suggest that carbon cycling can be affected by tillage management practices in agro-ecosystems.  Phosphodiesterase displayed a positive response to the late season drought treatment, suggesting that phosphrus cycling is highly dependent on soil moisture availability in the semi-arid cropping systems of the West Texas high plains.