2026-08-15 AGRICULTURE ECOSYSTEMS & ENVIRONMENT 2026 406(卷), null(期), (null页)
Livestock grazing is a dominant land use in dryland ecosystems around the world, and grazing can have widely varying impacts on soil carbon dynamics and microbial activity. Interactions between soil organic carbon (SOC) levels and extracellular enzyme activity (EEA) are varied, and the response of each to grazing management is poorly understood. We measured SOC and EEA of eight enzymes in the top 10 cm of soil in a 12-year study of five bovine grazing treatments in semi-arid prairie in eastern Montana, USA. We observed that surface SOC and EEA were more sensitive to initial soil conditions than long-term grazing treatments. Conversely, final SOC and total cellulase activity were positively correlated. Furthermore, change in topsoil SOC over the study was positively correlated with the ratio of carbon- to nitrogen-dissolving hydrolytic enzymes. Despite the lack of grazing management effects on topsoil carbon and soil EEA, we detected complex relationships between SOC and enzyme activities demonstrating the need for further investigation.