Turfgrass Species Selection and Stand Age Effects on Soil Carbon and Nitrogen Dynamics of Indiana Home Lawns.

Turfgrasses have shown potential to sequester carbon (C) in soil, which can mitigate buildup of the greenhouse gas carbon dioxide.  Carbon is stored in soil in various pools of activity ranging from labile to non-labile, and plant species ultimately affects the quantity and rate of change between these C pools.  Permanganate oxidizable carbon (POXC) is a relatively new method that can quantify labile soil C quickly and inexpensively, and has shown a greater sensitivity to management or environmental variation than particulate organic C, microbial biomass C, or soil organic C.  Evaluating turfgrass species, stand age, and soil depth on the various C pools of activity is essential for better understanding C sequestration in turfgrass systems.  Therefore, the objective of this research was to quantify the labile and non-labile soil C pools in mature Kentucky bluegrass (Poa pratensis), tall fescue (Schedonorus arundinaceus), and zoysiagrass (Zoysia japonica) stands varying in age located throughout central Indiana.  Soil samples were collected and classified based on species, age, depth and subsequently analyzed for POXC, total organic C and N, and total C and N.  Results to be discussed.