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Climate change is disrupting natural processes globally. Grasslands cover as much as 40% of the earth's terrestrial surface and appropriate management could increase the amount of carbon stored in these ecosystems, thereby providing valuable offsets to rising atmospheric carbon dioxide levels.  Presently there is limited knowledge of the underlying mechanisms that may regulate: 1) the dynamics of C cycling in grasslands, and 2) the potential for increasing C sequestration therein. Grazing practices have been shown to strongly influence plant community assemblages, which in turn, have the potential to influence C and nutrient cycling by changing the amount, timing and quality of litter inputs. Moreover, these changes are likely to occur both above and below ground, thus affecting microbial activity. As the proximate drivers of C and nutrient cycling, microbes produce extracellular enzymes responsible for converting organic matter into simpler compounds and making nutrients available for plant uptake. Ultimately, a better understanding of extracellular enzyme activities in the context of plant community change under livestock grazing will improve our understanding of the fate and residence time of C and nutrients in grasslands. We sampled soils in grazed and long-term non-grazed pastures along a biogeoclimatic gradient (~300-500 mm annual precipitation) across Alberta, Canada. Here we compare the activities of cellulase, hemicellulase, ligninase, phosphatase and glucoseaminidase, a suite of enzymes responsible for the break-down of organic substrates in the surface (0-15 cm) and subsurface soil horizons (15-30 cm), and link these to agro-climatic conditions, the presence of livestock grazing, and other soil characteristics. In the long term, our results aim to inform biogeochemical and economic models, as well as land management practices that will increase C sequestration in grasslands.