This file contains the soil profile data for burned and unburned moist acidic tundra sites used to estimate C and N loss from the Anaktuvuk River Fire (2007). These sites were sampled in summer of 2008. Unburned sites were used to develop a method for estimating soil organic layer depth and plant biomass, and for determining the characteristics of unburned soil organic layers. In burned sites, we characterized residual organic soils and used biometric measurements of tussocks to reconstruct pre-fire soil organic layer depth.
Data Set Results
These data were collected in July 2011 for tussocks transplanted in 1980-82 in a reciprocal transplant experiment and harvested in 2011. Important variables are garden name, source population, and dark respiration.
1997 measurements of Leaf area, foliar C and N for 14 sites along a transect down the Kuparuk River basin, North Slope, Alaska.
Above ground plant and below ground stem biomass, percent nitrogen, and percent carbon were measured in the Arctic LTER moist acidic tundra experimental plots. Treatments included control, and nitrogen and phosphorus amended plots for 10 years, and exclosure plots with and without added nitrogen and phosphorus.
Above ground plant and below ground stem biomass, percent nitrogen, and percent carbon were measured in the Arctic LTER dry heath tundra experimental plots. Treatments included control, and nitrogen and phosphorus amended plots for 10 years, and exclosure plots with and without added nitrogen and phosphorus.
Above ground plant and belowground stem biomass was measured in moist acidic and non-acidic tussock tundra experimental sites. Treatments sampled were control plots and plots amended with nitrogen and phosphorus.
Percent carbon, percent nitrogen, del13C and del15N were measured from above ground plant and belowground stem biomass samples from experimental plots in moist acidic and moist non-acidic tundra. Biomass data are in 2000lgshttbm.dat.
Ecosystem-level Carbon dioxide fluxes were measured in two long-term experimental wet sedge tundra sites near Toolik Lake, AK. Experimental treatments at each site included factorial NxP, greenhouse and shade house and were begun in 1985 (Sag site) or in 1988 (Toolik sites). Fluxes were measured on quadrats that were later sampled for biomass and leaf area.
Biomass in wet sedge tundra near the Atigun River crossing of the Dalton Highway, North Slope AK. .There were three harvests; Late May-early June; Late July-early August; Late August-early September. See Shaver and Chapin (Ecological Monographs, 61, 1991 pp.1-31.
Biomass, nitrogen and carbon of plants in the Arctic LTER experimental wet sedge tundra experimental sites, 2001, Toolik Lake, Alaska.. Treatments at each site included factorial NxP, greenhouse and shade house and were begun in 1985 (Sag site) or in 1988 (Toolik sites).
Biomass in tussock tundra near Toolik Lake North Slope AK (68 degrees 38N, 149derees 34W). There were three harvests;Late May-early June; Late July-early August; Late August-early September. See Shaver and Chapin (Ecological Monographs, 61(1), 1991 pp.1-31.
Biomass in shrub tundra near Toolik Lake North Slope AK (68 degrees 38N, 149derees 34W). There were three harvests; Late May-early June; Late July-early August; Late August-early September. See Shaver and Chapin (Ecological Monographs, 61(1), 1991 pp.1-31.
Plant biomass in arctic heath experimental plots. Plots set up in 1989 with nitrogen, phosphorus, nitrogen plus phosphorus and a shade treatment were harvested for above ground biomass. Root mass was also measured on a smaller subsample.
Biomass in heath tundra near Toolik Lake North Slope AK (68 degrees 38N, 149derees 34W). .There were three harvests;Late May-early June; Late July-early August; Late August-early September. See Shaver and Chapin (Ecological Monographs, 61(1), 1991 pp.1-31.
Plant biomass, leaf area, carbon, nitrogen, and phosphorus were measured in three wet sedge tundra experimental sites. Treatments at each site included factorial NxP and at the Toolik sites greenhouse and shade house. Treatments started in 1985 (Sag site) and in 1988 (Toolik sites).
Below ground soil bulk density, carbon and nitrogen was measured at various depth increments in mineral and organic soil layers at three sites at and around the Anaktuvuk River Burn: severely burned, moderately burned and unburned. This data corresponds with the aboveground biomass and root biomass data files: 2011ARF_AbvgroundBiomassCN, 2011ARF_RootBiomassCN_byDepth, 2011ARF_RootBiomassCN_byQuad, 2011ARF_RootBiomassCN_byQuad.
Summarized below ground soil carbon and nitrogen concentrations measured in quadrats at three sites at and around the Anaktuvuk River Burn: severely burned, moderately burned and unburned. This data corresponds with the aboveground biomass and root biomass data files: 2011ARF_AbvgroundBiomassCN, 2011ARF_RootBiomassCN_byDepth, 2011ARF_RootBiomassCN_byQuad, 2011ARF_SoilCN_byDepth.
Above ground plant and below ground stem biomass was measured in the Arctic LTER acidic tussock tundra experimental plots. Treatments included control, nitrogen plus phosphorus amended plots for either 6 or 13 years and vole exclosure plots with or without amends of nitrogen and phosphorus.
Above ground plant biomass and leaf area were measured in a tussock tundra experimental site. The plots were set up in 1981 and have been harvested in previous years (See Shaver and Chapin Ecological Monographs, 61, 1991 pp.1-31).
Percent carbon and percent nitrogen were measured from above ground plant and belowground stem biomass samples from experimental plots in moist acidic and moist non-acidic tundra. Biomass data are in 2001lgshttbm.dat.
Aboveground plant and belowground stem biomass were measured in moist acidic and moist non-acidic tussock tundra experimental plots. Treatments at the acidic site include control and nitrogen (N) plus phosphorus (P) amendments; treatments at the non-acidic site include N, P, N+P, greenhouse warming, and greenhouse+N+P.
Note: Version 8 corrected an error where Carex vaginata was listed twice under treatment of "Nitrogen Phosphorus". The tissues with 8 quadrats were "Greenhouse" treatment.
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 the Multiple Element Limitation (MEL) model to examine the responses of twelve ecosystems - from the arctic to the tropics and from grasslands to forests - to elevated carbon dioxide (CO2), warming, and 20% decreases or increases in annual precipitation.
We use the Multiple Element Limitation (MEL) model to examine the responses of twelve ecosystems - from the arctic to the tropics and from grasslands to forests - to elevated carbon dioxide (CO2), warming, and 20% decreases or increases in annual precipitation.
Climate change is increasing extreme weather events, but effects on high-frequency weather variability and the resultant impacts on ecosystem function are poorly understood. We assessed ecosystem responses of arctic tundra to changes in day-to-day weather variability using a biogeochemical model and stochastic simulations of daily temperature, precipitation, and light. Changes in weather variability altered ecosystem carbon, nitrogen, and phosphorus stocks and cycling rates.
Climate change is increasing extreme weather events, but effects on high-frequency weather variability and the resultant impacts on ecosystem function are poorly understood. We assessed ecosystem responses of arctic tundra to changes in day-to-day weather variability using a biogeochemical model and stochastic simulations of daily temperature, precipitation, and light. Changes in weather variability altered ecosystem carbon, nitrogen, and phosphorus stocks and cycling rates.