Influence of Vegetative Succession on Soil Chemistry of the Berkshires

摘要

The study characterizes the chemistry of precipitation, canopy leaching, and stream water as well as analyzing soil properties in a series of successional forest stands in Northwestern Berkshire County, Massachusetts. Dramatic changes occur in the pH of precipitation as it passes through forested ecosystems. Bulk precipitation has a mean pH of around 4.2, whereas streamflow has a mean pH of near 7.0. The pH, Ca, Mg, Na, K, NH4, DOC, NO3, F, Fe, Al, and CEC of soils all show consistent patterns of change with depth and are influenced by parent material and biological processes. The influence of succession on the evolution of soil pH appears to be controlled more by species composition than by age per se. Soils supporting coniferous species, oaks, or red maple usually have lower pH and basic cation concentrations than do soils supporting sugar maple, white ash, or birch species.