Impact of Land Use Change On Biogeochemical Cycling In the Florida Panhandle.

The Gulf Coast of Florida has been considered a “hotspot” of population growth and very few studies exist that focus on the impact of land use change on biogeochemical cycling along coastlines.  Previous research in the Florida panhandle has indicated that shifts in land use from pine flatwoods and maritime forests to urban forests increases carbon storage in the top 90 cm of the mineral soil.  Urban forest pine dominated sites can have a forest floor mass of 97 Mg ha^-1, a significantly higher mass than that stored in the forest floor of pine plantations and naturally regenerating forest (33 to 38 Mg ha^-1 , respectively).   The focus of this research is to investigate the impact of land use change on carbon and nutrient cycling by measuring foliar decomposition rates, nitrogen mineralization and microbial biomass over a two year period.   Plots representing five different land use types (pine plantation, urban forest pine dominated, urban forest oak dominated, natural forest pine dominated, and natural forest oak dominated) were blocked across  four soil drainage classifications (very poorly drained, poorly drained, somewhat poorly drained and moderately well drained).  The litter-bag decomposition component is ongoing and decomposition rates for 28 weeks will be presented.  Nitrogen mineralization and microbial biomass measurements began in June 2010.  When significant differences were detected ( August , October and November 2011 collections), urban forests stand out as having higher contents of microbial biomass and higher rates of nitrogen mineralized as nitrate.