Agricultural management effects on soil health across the US Southern Great Plains

Abstract

Improving soil health is commonly suggested as a way to “buffer” agricultural systems against climate change impacts such as increases in drought, storm severity, and annual temperature. A number of producers in the US Southern Great Plains (SGP) and elsewhere have begun to manage their systems with an emphasis on improving soil health, but adoption of these practices is not yet widespread. There is evidence that soil health management (SHM) has positive effects on soil health that conventional management (CM) does not, but the effects have not been compared to sustainability managed conventional systems, nor have they been quantified using a standard method across regional climatic gradients such as those that characterize the SGP. In this study, we used a network of three pairs of SHM and CM sites at 12 locations in Kansas, Oklahoma, and Texas to test a suite of biological, chemical, and physical soil health indicators. We analyzed differences among these indicators to better understand how SHM and CM fields compared across the region, and to identify potential effects of precipitation and temperature on these differences. We found that responses to management were not uniform across the SGP and that soil health indicators responded primarily to climate, rather than to management practices. These results suggest that soil health responses as a result of SHM may be constrained by other factors, resulting in variations across the landscape that make soil health assessments challenging. Our findings underscore the importance of understanding management and other impacts on soil health when developing realistic land management goals.