Changes in total C and N, d13C and d15N, C:N ratio in green leaves and parts of mosses (for sphagnum, both red and green tips were included) over time since 15NH4 addition in Imnavait watershed.
Data Set Results
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Average conductivity of the epilimnion (0-3m of water depth) found in Toolik Lake during the month of July.
Physical (bulk density, soil thickness) and chemical (total C and N, d13C and d15N) information of soil cores taken from 15N addition plots in Imnavait watershed.
Decadal file describing the physical/chemical values recorded at various lakes near Toolik Research Station during summers from 2000 to 2009. Sample site descriptors include site, date, time, depth. Depth profiles of physical measures collected in situ with Hydrolab Datasonde in the field include temperature, conductivity, pH, dissolved oxygen in both percent saturation and mg/l, SCUFA chlorophyll-a values in both volts and µg/l, and PAR.
Decadal file describing the physical/chemical values recorded at various lakes near Toolik Research Station during summers from 1990 to 1999. Sample site descriptors include site, date, time, depth. Depth profiles of physical measures collected in situ with Hydrolab Datasonde in the field include temperature, conductivity, pH, dissolved oxygen in both percent saturation and mg/l, SCUFA chlorophyll-a values in both volts and µg/l, and PAR.
Decadal file describing the physical/chemical values recorded at various lakes near Toolik Research Station. Sample site descriptors include site, date, time, depth. Depth profiles of physical measures collected in situ with Hydrolab Datasonde in the field include temperature, conductivity, pH, dissolved oxygen in both percent saturation and mg/l, SCUFA chlorophyll-a values in both volts and µg/l, and PAR.
Carbon, nitrogen and phosphorus content in thawed soils are described for four arctic tundra vegetation types located near the Toolik Field Station.
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.
We measured the flux of bulk material and major macronutrients (carbon, nitrogen and phosphorus) from the water column to the benthos in four separate lakes during the summer of 2009. The lakes were chosen to investigate the impacts of disturbance on lake sedimentation. Two of the lakes, Dimple and Perched, were within catchments that were burned by the 2007 Anaktuvuk River wildfire. Two of the lakes, NE-14 and Perched, were receiving elevated sediment loads from thermokarst failures on their shorelines, and Toolik Lake was used as a reference lake.
Data file describing the biogeochemistry of samples collected at various sites near Toolik Lake, North Slope of Alaska. Sample site descriptors include a unique assigned number (sortchem), site, date, time, depth, distance (downstream), elevation, treatment, date-time, category, and water type (lake, surface, soil). Physical measures collected in the field include temperature (water, soil, well water), conductivity, pH, average thaw depth, well height, discharge, stage height, and light (lakes).
Data file describing the biogeochemistry of samples collected at various sites near Toolik Lake, North Slope of Alaska. Sample site descriptors include a unique assigned number (sortchem), site, date, time, depth, distance (downstream), elevation, treatment, date-time, category, and water type (lake, surface, soil). Physical measures collected in the field include temperature (water, soil, well water), conductivity, pH, average thaw depth, well height, discharge, stage height, and light (lakes).
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).
Leaf areas were measured on quadrats harvested in Arctic LTER tussock tundra experimental small mammal exclosures. Treatments included Control, Nitrogen plus Phosphorus with both fenced and unfenced plots. In addition a moist non-acidic tussock tundra site was harvested. Biomass was also measured for each quadrat but is in a separate file.
Nitrogen mineralization was determined on LTER and Sag River tussock tundra using the buried bag method. Yearly bags have been deployed every August since 1990.
Above ground plant biomass was 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(1), 1991 pp.1-31.) This file is the July 26-27, 1984 harvest of the controls and nitrogen + phosphorus treatments.
Since 1983, the Streams Project at the Toolik Field Station has monitored physical, chemical, and biological parameters in a 5-km, fourth-order reach of the Kuparuk River near its intersection with the Dalton Highway and the Trans-Alaska Pipeline. In 1989, similar studies were begun on a 3.5-km, third-order reach of a second stream, Oksrukuyik Creek.
Water chemistry (NO3, NH4, TDN, DON, DOC) from Imnavait watershed along hillslope. Sample waters were either collected by lysimeters, needle with syringe, or extracting soil with water or 1N KCl.
Concentrations of NO3 and NH4 and d15N of NO3 and NH4 collected on resin bags from 15N addition plots along hillslope in Imnavait watershed.
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.
Decadal file describing the water chemistry in various lakes near Toolik Research Station (68 38'N, 149 36'W) during summers from 1990 to 1999. Chemical analyses were conducted on samples from various depths in the sample lakes either once, or multiple times during the spring, summer and fall months (May to September).
Decadal file describing the water chemistry in various lakes near Toolik Research Station (68 38'N, 149 36'W) during summers from 2000 to 2009. Chemical analyses were conducted on samples from various depths in the sample lakes either once, or multiple times during the spring, summer and fall months (May to September).
Note: Corrections were made to Particulate phosphorus values. See version 5 notes.
Decadal file describing the water chemistry in various lakes near Toolik Research Station (68 38'N, 149 36'W) during summers from 1983 to 1989. Chemical analyses were conducted on samples from various depths in the sample lakes either once, or multiple times during the spring, summer and fall months (May to September).
Relative percent cover was measured for plant species on Arctic LTER experimental plots at Toolik field station in moist acidic and non-acidic tundra.
Measures of soil nutrient content (available N and P, Extractable N and P, Total C, N and P), and microbial biomass and activity (exoenzyme activity) were measured for organic and mineral soils on Arctic LTER experimental plots at Toolik field station in moist acidic and non-acidic tundra (organic soils only).
Transplant gardens at Toolik Lake and Sagwon were established in 2014. At each location, 60 tussocks each from ecotypes of Eriophorum vaginatum from Coldfoot (CF, 67°15′32″N, 150°10′12″W), Toolik Lake (TL, 68°37′44″N, 149°35′0″W), and Sagwon (SG, 69°25′26″N, 148°42′49″W) were transplanted. At the reciprocal transplant gardens, ion exchange membranes were used to measure nutrient availability over two time periods: Early season (June) and mid season (July). Membranes were deployed in the field for either 20 or 21 days, depending on travel constraints.
Data file of the biogeochemistry of samples collected at various sites near Toolik Lake, North Slope of Alaska. Sample site descriptors include a unique assigned number (sortchem), site, date, time, depth, distance (downstream from a reference location), elevation, treatment, date-time, category, and water type (lake, surface, soil). Physical measures collected in the field include temperature (water, soil, well water), conductivity, pH, and average thaw depth in soil. Chemical analyses for the sample include alkalinity; dissolved inorganic and organic carbon (DIC and DOC); dissolved gas
Dissolved organic carbon (DOC) was leached from permafrost soils near the Toolik Field Station in the Alaskan Arctic and then characterized for its photochemical properties. Oxygen (O2) consumed from photo-oxidation of permafrost DOC was measured as a function of sunlight wavelength, defined as the apparent quantum yield spectrum of photo-oxidation (O2 consumed per mol photon absorbed by DOC). Carbon dioxide (CO2) produced from photomineralization of permafrost DOC was measured as a function of sunlight wavelength, defined as the apparent quantum yield spectrum of photomineralization (CO2
Dissolved organic carbon (DOC) was leached from permafrost soils near the Toolik Field Station in the Alaskan Arctic and then characterized for its photochemical properties. The radiocarbon (14C) and stable carbon (13C) isotopic compositions of carbon dioxide (CO2) photochemically produced from permafrost DOC were quantified.
Dissolved organic carbon (DOC) was leached from permafrost soils collected from the frozen permafrost layer at five sites underlying moist acidic tussock or wet sedge vegetation, and on three glacial surfaces on the North Slope of Alaska during summer 2018.
Dissolved organic carbon (DOC) was leached from permafrost soils near the Toolik Field Station in the Alaskan Arctic and then characterized for its photochemical properties. The apparent quantum yield of photomineralization (photochemical carbon dioxide, CO2, production) of permafrost DOC was quantified at 309 nm.
Data file describing high frequency (every ~10 minutes), optial sensor-derived chemistry of river water from Oksukuyik Creek near Toolik Field Station, North Slope of Alaska. Data file includes date, time, dissolved organic carbon (DOC) concentration, and nitrate concentration. Sensors (V2 s::can uv-vis spectrophotometers) were continuously deployed from June through August or September and optically determined nitrate and dissolved organic carbon concentrations.
Data file describing high frequency (every ~10 minutes), optial sensor-derived chemistry of river water from Trevor Creek near Toolik Field Station, North Slope of Alaska. Data file includes date, time, dissolved organic carbon (DOC) concentration, and nitrate concentration. Sensors (V2 s::can uv-vis spectrophotometers) were continuously deployed from June through August or September and optically determined nitrate and dissolved organic carbon concentrations.
Data file describing repeated sampling of chemistry of distributed river water from the Kuparuk River, Oksrukuyik Creek, and Trevor Creek watersheds near Toolik Field Station, North Slope of Alaska. Data file includes sampling date, season, sampling point, subcatchment area, and resulting concentrations for a suite of solutes.
We investigated the effect of long-term warming on multiple soil and microbial carbon, nitrogen, and phosphorus pools, and microbial extracellular enzyme activities, with a particular focus on phosphorus, in Alaskan tundra plots underlain by permafrost
Relative percent cover was measured for plant species on Arctic LTER experimental plots at Toolik field station in moist acidic and non-acidic tundra
in greenhouse and control plots. Leaf percent carbon, percent nitrogen and percent phosphorus were collected from dominant species in greenhouse and control plots
on Arctic LTER experimental plots at Toolik field station in moist acidic, non-acidic tundra, wet sedge and shrub
tundra
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(1), 1991 pp.1-31.) This file contains the biomass numbers for each harvested quadrat and per cent carbon and nitrogen and phosphorous summaries for control and fertilized plots.
Soil temperatures at 2 depths, 5 and 10 cm, canopy temperatures and soil moisture at 10 cm were measured in a heath tundra Arctic Long Term Experimental Research (ARC-LTER) site at Toolik Lake Field Station, North slope, Alaska. Air temperature and relative humidity and global radiation were also measured but are presented in another dataset. Only control and nutrient addition (nitrogen plus phosphorus ) treatments plots were measured .