Do nitrogen budgets explain soil nitrogen mineralization rate differences between oak-pine and northern hardwood stands?
Bonito, Gregory1, Haines, Bruce1, Coleman, David1, 1 ABSTRACT- Nitrogen mineralization rates typically decrease with decreasing temperature. Temperature decreases with increasing elevation. Thus, N-mineralization rates are expected to decrease with increasing elevation. However, soil N-mineralization rates at the Coweeta Hydrologic Lab, N.C. are higher at the highest elevation. Causes of higher N-mineralization rates at the higher elevation have yet to be explained. Alternative hypotheses to explain higher N-mineralization rates at the higher elevation, Northern Hardwoods (NH) compared to the Oak-Pine (OP) include: 1) a mineralization promoter in decomposing herbs, leaf litter or soil of the high elevation, 2) low pH in OP soils inhibiting N-mineralization, 3) differences in total nitrogen pools, 4) low moisture limitation in OP soils, 5) differences in soil texture, and 6) differences in biological communities. Previous studies did not support our N-mineralization promoter hypothesis,
