Chemical properties of upland forest soils in the Catskills region.

The Catskills forest provides a valuable array of ecosystem services for local and regional populations, including the provision of forest products, wildlife habitats, and high-quality water. These services depend on chemical and biological processes that occur in forest soils. In 2011, we sampled soils in 25 headwater catchments in the Catskills region to quantify the pools of soil nutrients and examine the variation in soil properties in the region. The average soil depth in the 50 excavated pits was 56.6 cm. Average soil mass was 205 kg/m(2). The pools of soil carbon and nitrogen averaged 58.5 and 3.95 Mg/ha, respectively. The thin organic horizons accounted for less than 1% of soil mass, but included 14% of the soil carbon and 11% of soil nitrogen. Catskills forest soils are highly acidic, with mean pH ranging between 3.9 and 4.75. Base saturation was high (>60%) in organic horizons and low (12-31%) in mineral soils. The pool of exchangeable calcium is approximately equivalent to 20 years of calcium export from headwater streams, raising concerns regarding the ability of these catchments to maintain current stream calcium concentrations. The data and samples collected in this study provide a baseline for future soil monitoring in the region.