Hourly air temperature, humidity, wind speed, soil temperature and soil water data from the control area of the ITEX tussock tundra snowfence study site
Data Set Results
Hourly data from the Toolik Moist Non-acidic Tussock Experimental plots (MNT). In 1999 a Campbell CR10x data logger was installed in block 2 of the experimental plots. The plots are located on a hillside near Toolik Lake (68 38' N, 149 36'W). Sensors were placed in control and greenhouse sites. Soil temperature profiles are reported in another file (1999-present_MNTsoil).
Hourly air temperature, humidity, wind speed, soil temperature and soil water data from the control area of the ITEX dry heath study site
Hourly air temperature, humidity, wind speed, soil temperature and soil water data from an unmanipulated shrub patch measured from August 6, 2006 to September 12, 2010.
Soil temperature from three locations on the eastern side of the Toolik River where by snow fences were established as part of IPY. This is a study of how soil temperatures at 10 cm and soil moisture change across the summer at our IPY snow fence site .
This is a study of how different snow regimes effect CO2 exchange in tussock tundra and whether there are shifts in ecosystem C cycling when facets of "drift" effects are isolated. The study is part of the IPY program and is aimed at measuring the state of Arctic tundra.
This is a study of how different snow regimes effect CO2 exchange in tussock tundra and whether there are shifts in ecosystem C cycling when facets of "drift" effects are isolated. The study is part of the IPY program and is aimed at measuring the state of Arctic tundra.
The Changing Seasonality of Arctic Stream Systems (CSASN) was active from 2010 to 2012. The CSASN goal was to quantify the relative influences of through flow, lateral inputs, and hyporheic regeneration on the seasonal fluxes C, N, and P in an arctic river network, and to determine how these influences might shift under seasonal conditions that are likely to be substantially different in the future. Point transects were done throughout the sampling season to determine different substrate and cover types on the stream bottom.
The Changing Seasonality of Arctic Stream Systems (CSASN) was active from 2010 to 2012. The CSASN goal was to quantify the relative influences of through flow, lateral inputs, and hyporheic regeneration on the seasonal fluxes C, N, and P in an arctic river network, and to determine how these influences might shift under seasonal conditions that are likely to be substantially different in the future. During the project, well and mini-piezometer samples were collected from various depths near stream channels and analyzed for a variety of nutrients.
The Changing Seasonality of Arctic Stream Systems (CSASN) was active from 2010 to 2012. The CSASN goal was to quantify the relative influences of through flow, lateral inputs, and hyporheic regeneration on the seasonal fluxes C, N, and P in an arctic river network, and to determine how these influences might shift under seasonal conditions that are likely to be substantially different in the future. During the project, background samples were collected from four stream channels and analyzed for a variety of nutrients.
The Changing Seasonality of Arctic Stream Systems (CSASN) was active from 2010 to 2012. The CSASN goal was to quantify the relative influences of through flow, lateral inputs, and hyporheic regeneration on the seasonal fluxes C, N, and P in an arctic river network, and to determine how these influences might shift under seasonal conditions that are likely to be substantially different in the future. Whole Stream Metabolism was calculated using dissolved oxygen, discharge, stage, and temperature measured by sounds deployed in the field.
The (ARCSSTK) did extensive research during 2009-2011 field seasons in Arctic Alaska. Specifically, the ARCSSTK goal Streams goal was to quantify the relative influences of thermokarst inputs on the biogeochemical structure and function of receiving streams. Whole Stream Metabolism was calculated using dissolved oxygen, discharge, stage, and temperature measured by sondes deployed in the field.
Plant available NH4, NO3, and PO4 was determined at three site (LTER Toolik acidic tundra, LTER Toolik nonacidic tundra, and Sagwon acidic tundra) and three community combinations (tussock, watertrack, and snowbed), three times during the season. pH was also determined in July and strong acid phosphorous in August.
Relative percent cover was measured for plant species on Arctic LTER experimental plots at Toolik field station in moist acidic and moist non acidic tussock tundra, and dry heath tundra, and on Sagavanirktok River toposequence plots in tussock and heath tundra.
Relative percent cover was measured for plant species on Arctic LTER experimental plots in moist acidic and moist non-acidic tundra, Toolik Field Station, Alaska, Arctic LTER 1999.
We deployed three eddy covariance towers along a burn severity gradient (i.e. severely-, moderately-, and un-burned tundra) to monitor post fire Net Ecosystem Exchange of CO2 (NEE) within the large 2007 Anaktuvuk River fire scar during the summer of 2008. This data represents the 2009 post fire energy and mass exchange at the severe burn site.
We deployed three eddy covariance towers along a burn severity gradient (i.e. severely-, moderately-, and un-burned tundra) to monitor post fire Net Ecosystem Exchange of CO2 (NEE) within the large 2007 Anaktuvuk River fire scar during the summer of 2008. This data represents the 2012 post fire energy and mass exchange at the moderate burn site.
We deployed three eddy covariance towers along a burn severity gradient (i.e. severely-, moderately-, and un-burned tundra) to monitor post fire Net Ecosystem Exchange of CO2 (NEE) within the large 2007 Anaktuvuk River fire scar during the summer of 2008. This data represents the 2011 post fire energy and mass exchange at the moderate burn site.
We deployed three eddy covariance towers along a burn severity gradient (i.e. severely-, moderately-, and un-burned tundra) to monitor post fire Net Ecosystem Exchange of CO2 (NEE) within the large 2007 Anaktuvuk River fire scar during the summer of 2008. This data represents the 2010 post fire energy and mass exchange at the unburned site.
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.
Relative percent cover was measured for plant species on Arctic LTER experimental plots at Toolik field station in moist acidic and moist non acidic tussock tundra, and dry heath tundra.
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.
We deployed three eddy covariance towers along a burn severity gradient (i.e. severely-, moderately-, and un-burned tundra) to monitor post fire Net Ecosystem Exchange of CO2 (NEE) within the large 2007 Anaktuvuk River fire scar during the summer of 2008. This data represents the 2009 post fire energy and mass exchange at the unburned site.
Relative percent cover was measured for plant species on Arctic LTER experimental plots in moist acidic and moist non-acidic tundra.
We deployed three eddy covariance towers along a burn severity gradient (i.e. severely-, moderately-, and un-burned tundra) to monitor post fire Net Ecosystem Exchange of CO2 (NEE) within the large 2007 Anaktuvuk River fire scar during the summer of 2008. This data represents the first post fire growing season's energy and mass exchange at the moderate burn site.
A spectrophotometer was used to scan the canopy vegetation at four sites near Imnavait Creek each year from 2008 - 2010 by Toolik Lake LTER, Alaska. Reflectance spectra from 310-1130 nm are presented here with information relating the date and site of the scan.
A spectrophotometer was used to scan the canopy vegetation at four sites along Imnavait Creek in the Kuparuk Watershed near Toolik Lake LTER, Alaska. The resulting reflectance spectra were used to calculate average vegetation indices for each site and collection day.
We deployed three eddy covariance towers along a burn severity gradient (i.e. severely-, moderately-, and un-burned tundra) to monitor post fire Net Ecosystem Exchange of CO2 (NEE) within the large 2007 Anaktuvuk River fire scar during the summer of 2008. This data represents the 2010 post fire energy and mass exchange at the moderate burn site.
We deployed three eddy covariance towers along a burn severity gradient (i.e. severely-, moderately-, and un-burned tundra) to monitor post fire Net Ecosystem Exchange of CO2 (NEE) within the large 2007 Anaktuvuk River fire scar during the summer of 2008. This data represents the 2009 post fire energy and mass exchange at the moderate burn site.
Bulk precipitation was collected during summer months (June, July and August) on a per rain event basis at the University of Alaska Fairbanks Toolik Field Station, North Slope of Alaska (68 degrees 37' 42"N, 149 degrees 35' 46"W). Analysis of pH, NH4-N and phosphorus were performed at the field station. NO3-N were frozen and analyzed in Woods Hole, MA
We deployed three eddy covariance towers along a burn severity gradient (i.e. severely-, moderately-, and un-burned tundra) to monitor post fire Net Ecosystem Exchange of CO2 (NEE) within the large 2007 Anaktuvuk River fire scar during the summer of 2008. This data represents the 2012 post fire energy and mass exchange at the unburned site.
Extractable NH4-N and NO3-N (2 N KCl), PO4-P
(0.025 N HCl) and pH (0.01 M CaCl2) were measured on soils from a
transect along the Dalton road. Sites are Gus Shaver flowering sites and
Arctic LTER sites.
We deployed three eddy covariance towers along a burn severity gradient (i.e. severely-, moderately-, and un-burned tundra) to monitor post fire Net Ecosystem Exchange of CO2 (NEE) within the large 2007 Anaktuvuk River fire scar during the summer of 2008. This data represents the 2011 post fire energy and mass exchange at the unburned site.
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.
We deployed three eddy covariance towers along a burn severity gradient (i.e. severely-, moderately-, and un-burned tundra) to monitor post fire Net Ecosystem Exchange of CO2 (NEE) within the large 2007 Anaktuvuk River fire scar during the summer of 2008. This data represents the 2011 post fire energy and mass exchange at the severe burn site.
Quadrats (20cm x 20cm squares) along a line (block) were collected for plant biomass in mesic tussock tundra. In the lab each quadrat was separated into individual species, new and old aboveground and belowground biomass. Two harvests were completed, June and a late July. These are control plots from an experiment setup for a 15N experiment.
Five or six quadrats (20cm x 20cm squares) along a line (block) were collected for plant biomass in mesic tussock tundra. In the lab each quadrat was separated into individual species, new and old aboveground and belowground biomass.
Vegetation indices calculated from reflectance spectra collected at Arctic LTER experimental plots at Toolik Lake, Alaska during the 2007-2019 growing seasons.
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.
Vascular plant species list, by quadrat, for harvests of tussock tundra, wet sedge tundra, dry heath tundra, and a toposequence which also included "shrub/lupine," "riverside willow" and "footslope Equisetum" communities. Includes results of long-term nutrient enrichment, increased temperature, and shade houses in selected tundra types.
Late season thaw depth was measured in the Arctic Long Term Ecological Research (ARC LTER) experimental plots (1981 Moist Acidic Tussock, 1989 Moist Acidic Tussock, 2006 Low Fertilization Moist Acidic Tussock, 1989 Moist Non-acidic Tussock, 1989 Moist Non-acidic Non-tussock and 1989 Wet Sedge tundra) at Toolik Lake, Alaska using a steel thaw probe. Note: for 2017-2018 only 1989 Moist Non-Acidic Tussock Tundra and 2006 Low fertilization Moist Acidic Tussock Tundra were measured. For other sites it has become difficult to distinguish rocks from frozen soil with a steel thaw probe.
Biomass was harvested from six vegetation types along a toposequence on a floodplain terrace of the Sagavanirktok River in the northern foothills of the Brooks Range , Alaska (68degrees 46' N, 148 degrees 51' W 50m). The vegetation sites are; upland tussock tundra, "hilltop heath", a "hillslope shrub-lupine", a "footslope Equisetum", a wet sedge tundra, and a "riverside willow".
Quadrats (20cm x 20cm squares) along a line (block) were collected for plant biomass in mesic acidic tussock tundra. Each quadrat was separated into individual species, new and old aboveground and belowground biomass. The harvest occurred in early July to coincide with a 15N plant and soil harvest.
Quadrats were harvested for aboveground biomass from eight plots within a tussock, watertrack, and snowbed community at 3 sites - acidic tundra near Toolik (site of acidic LTER plots), nonacidic tundra near Toolik Lake(site of non-acidic LTER plots), and acidic tundra near Sagwon. All vascular species were sorted, divided into new and old growth, dried, and weighed. Lichens were separated by genus in all quadrats. In half of the quadrats (n=4), mosses were separated by species. Moss and lichen data are presented by species elsewhere (see 97lgmosslichen.txt).
Leaf area for select species was measured in arctic tundra experimental sites from late June into early August. Measurements were made in acidic and non acidic tussock tundra and in shrub tundra in control and fertilized plots.
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 available NH4, NO3, and PO4 was determined at sites near ARC LTER Toolik acidic tundra and at a toposequence along the floodplain of the Sagavanirktuk River using 2 N KCL and weak HCL extracts. This file complies data collected at different times from 1987 through 2001 and includes initial extracts taken for buried bag method of net nitrogen mineralization.
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 contains the biomass numbers for each harvested quadrat.