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).
Data Set Results
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.
Vegetation indices calculated from reflectance spectra collected at Arctic LTER experimental plots at Toolik Lake, Alaska during the 2007-2019 growing seasons.
A spectrophotometer was used to scan the canopy vegetation of ITEX harvest plots. The resulting reflectance spectra were used to calculate several vegetation indices of interest (NDVI, EVI, EVI2, PRI, WBI, Chlorophyll Index). Average values of these vegetation indices for each ITEX harvest plot are presented here. These plots also had biomass harvests performed and were analyzed for leaf area and nitrogen content (see 2003-2009gsharvest.csv, 2003-2009gsharvestLAI-N.csv).
Inorganic Nitrogen and phosphorus were analyzed on snow samples taken from two snow pits near the long-term acrtic LTER mesic acidic tussock experimental plots. The snow layers in each pit were described and sampled separtely with the help of Matthrew Sturm.
A spectrophotometer was used to scan the canopy vegetation of ITEX flux plots. The resulting reflectance spectra were used to calculate several vegetation indices of interest (NDVI, EVI, EVI2, PRI, WBI, Chlorophyll Index). Average values of these vegetation indices for each ITEX flux plot are presented here.