Professor Johnson is conducting research on biogeochemical processes in forest ecosystems that were historically impacted by acid rain. He is analyzing soils from 25 watersheds in the Catskill Mountain region of New York for elemental content. Data from those analyses, along with measurements of stream water chemistry and precipitation chemistry will be used to estimate the release of Ca, Mg, K, Na and Si from soil minerals in these watersheds. This project will help to create a more holistic view of forest ecosystem structure and function with respect to water quality protection.