Soil samples were collected from control, and N+P plots from within a set of treatments in Arctic LTER Moist Acidic Tundra plots established in 1989 and in 2006 . At the time of sampling the soil was separated into organic horizon, organic/mineral interface, and the upper 5cm of the mineral soil. In the lab the potential activities of seven hydrolytic enzymes was determined using fluorometric techniques (Saiya-Cork et al. 2002) modified following Steinweg et al(.2012).
Soil aggregate size distribution, aggregate carbon and nitrogen, and light fraction carbon were determined for mineral soils in moist acidic tundra. Soil was sampled in control, and N+P plots of the Arctic LTER Moist Acidic Tundra plots established in 1989 and 2006.
The original focus of this study was an analysis of proteolytic enzyme activity of Alaskan arctic tundra soils, however initial results raised questions regarding the method (Watanabe and Hayano, 1995). Thus, the goals of the study changed to 1) an investigation of the method, and 2) a comparison of enzyme activities of two different soil layers from the arctic tundra.