Although air pollution and soil heavy metals are higher in New York than in rural sites, litter decomposition rates in oak forests located along an urban-rural gradient were surprisingly faster in urban sites. To determine whether differences in leaf quality contribute to faster decay rates of urban litter, Dr. Carriero will conduct a decomposition experiment on newly fallen oak leaves collected along the gradient and incubated in the laboratory. Since temperature, moisture, and microbial inoculum will be standardized, the experiment will directly assay whether the quality of living oak leaves has been changed enough in cities to result in more rapid decay after leaf fall. Dry weight loss of laboratory-incubated litter will be measured at intervals over a 4-month period. Growth and respiratory activity of fungi and bacteria colonizing litter will also be measured as decay progresses to determine responses to possible differences in leaf quality. An understanding of mechanisms behind the different litter decay rates in urban and rural forests is important since decomposition rates regulate nutrient flows within these ecosystems and influences nutrient availability to plants. The facilities available for conducting this research are first-rate. ***
