Grazing induces changes in nutrient transformations by removing aboveground biomass and stimulating microbial activity and the forms and availability of soil nutrients. These changes can lead to changes in plant species composition, which, in the long-term, may affect litter quality, mass and seasonal dynamics of litter inputs. Cycling of nutrients through grazers may increase the readily-mineralizable pool of nutrients at the soil surface where they are more accessible for uptake by plants and microorganisms. Grazing can increase N mineralization at the landscape scale, overriding influences of local topography. Consequently shoots of plant from grazed areas can have greater nutrient concentration than shoots from non-grazed areas.
Grazing can also alter the allocation of energy to the belowground foodweb.
These interactions are extremely important to overall system function. There is a lack of general principles concerning grazing influences on belowground processes, due to the complexity of interactions and the variety of mechanisms that mediate grazing influences. Furthermore, there is a general lack of information on these complex interactions, indicating a need for more research in this area under a variety of experimental settings. One of my research projects addressed grazing influences on nutrient mineralization, and microbial transformations of nutrients and energy in soils. This project is part of a large multi-disciplinary research project examining the influence of cattle stocking density on various ecosystem components in experimental pastures at Buck Island ranch.