Composite file describing plant, animal, water, and sediment samples collected at various sites near Toolik Research Station (68 38'N, 149 36'W). Sample site descriptors include an assigned number specific to the file, a number that relates the samples to other samples collected on the same date and time (sortchem), site, date, time, and depth. Samples are identified by type, category, and a short description. Data include isotope values, carbon and nitrogen concentrations, and C:N ratios of samples.
Data Set Results
The percent carbon and nitrogen from leaves of shoots harvested from 1m x 1m point frame plots the summer of 2012 at Toolik Lake, Alaska. were measured on a ThermoScientific 2000. For each point frame plot, six shoots were harvested from upper, middle, and low sections of the canopy. The photosynthetic capacity of each shoot was analyzed with a LiCor 6400 infra-red gas analyzer by being run through a light response and A/Ci curve.
Tillers from 24 Eriophorum vaginatum individuals were sampled in late July 2019 to examine differences in percent nitrogen between previously burned (Anaktuvuk River Fire) and unburned tussocks at a nearby unburned control site. At the burned site tussocks exhibiting evidence of rodent grazing were also sampled to separate herbivore effects from those of the fire. From each tussock, 3-4 new leaves were sampled (as indicated by lack of brown tips) and dried at 60°C for 24 hours, before being ground and analyzed for percent nitrogen.
This file contains Eriophorum vaginatum rhizome biomass from a 2017 biomass pluck of previously burned tundra (2007 Anaktuvuk River Fire) and nearby unburned tundra. Rhizome biomass from the pluck was combined with rhizome percent nitrogen estimates (2.47% at the Anaktuvuk River Fire, and 1.05% at the nearby unburned site) to estimate grams of nitrogen per meter squared, to evaluate differences in winter forage quality for the rodent herbivore, Microtus oeconomus. Percent nitrogen estimates were derived from pooled rhizome samples collected from the two sites in late 2018.