del 13C and del 15N ratios were measured for plant and lichen in watertracks in the Toolik Lake drainage and the east facing slope of the Imnavait Creek area. Sampling locations for each species for a specific date were chosen across an elevation gradient starting from the lakeside and leading to ridge crest. The vegetation was dried and analyzed for stable isotopes.
Data Set Results
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.
The data set describes stable carbon and nitrogen isotopes and carbon and nitrogen concentrations from an August 2012 pluck of a fertilization experiment begun in 2006. Fertilization was with nitrogen (N) and phosphorus (P). Fertilization levels included control, F2, F5, and F10, with F2 corresponding to yearly additions of 2 g/m2 N and 1 g/m2 P, F5 corresponding to yearly additions of 5 g/m2 N and 2.5 g/m2 P, and F10 corresponding to yearly additions of 10 g/m2 N and 5 g/m2 P. After harvest, plants were separated by species and then by tissue.
We use a simple model of coupled carbon and nitrogen cycles in terrestrial ecosystems to examine how explicitly representing grazers versus having grazer effects implicitly aggregated in with other biogeochemical processes in the model alters predicted responses to elevated carbon dioxide and warming. The aggregated approach can affect model predictions because grazer-mediated processes can respond differently to changes in climate from the processes with which they are typically aggregated.
We use a simple model of coupled carbon and nitrogen cycles in terrestrial ecosystems to examine how explicitly representing grazers versus having grazer effects implicitly aggregated in with other biogeochemical processes in the model alters predicted responses to elevated carbon dioxide and warming. The aggregated approach can affect model predictions because grazer-mediated processes can respond differently to changes in climate from the processes with which they are typically aggregated.