This file contains irradiance (PAR) and diffuse light data logged from a beam fraction (BF3) sensor near Toolik Lake, Alaska during the summer of 2012. The data comes from a compilation of automated datalogger readings as well as measurements taken during the field season in conjunction with the Delta-T SunScan wand to measure PAR in tall shrub canopies dominated by Betula nana or Salix pulchra species. The sensor was leveled and mounted to a 2m tripod in each location, and programmed to record instantaneous readings in 30 second to 5 minute intervals.
Data Set Results
"2012_GS_PFandCH_GPS" contains GPS locations of all datalogger, 1m x 1m chamber flux and point frame plots sampled IVO Toolik Field Station in Alaska during the summer of 2012. The sorting variables (YEAR, DATE, SITE, GROUP, PLOT, TREAT, PLOT SIZE) are identical to those in other files with data collected that season. The main purpose of this file is for reference and as an aid in interpretation of data analyses and among-site comparisons.
Within-canopy PAR was measured with a Delta-T SunScan wand every 15 cm from the ground to above the canopy under both direct and diffuse light. The data includes all outputs from the SunScan wand: time of measurement, spread of PAR sensors, total irradiance, total diffuse light, and individual outputs of 64-PAR sensors on the SunScan wand. These measurements were taken for 1m x 1m chamber flux (n=14) and point frame (n=19) plots as well as sites four montitored remotely by PAR sensors located above, within, and below shrub canopies.
Leaf and plant tissue area and mass from shoots harvested from 19 1m x 1m point frame plots near Toolik Field Station, AK during the summer of 2012. Six shoots were harvested from each plot, two from each canopy layer: upper, middle, and low. Each shoot came from a different plant, and the species selected was based on the species dominant in that canopy layer. The leaf area and mass were used to correct A/Ci and light response curves taken on each shoot [data published separately].
Peat cores were collected along the Dalton Highway in 1989 and analysed for percent moisture, percent organic carbon, bulk densitey, del C-13, and radiocarbon content at varying depth intevals throughout the core. Samples were collected to the mineral zone and kept in cold storage until analysis. Samples were collected from 12 sites.
This file contains PAR , relative humidity, and temperature data logged every five minutes from within, below, and above Betula nana and Salix pulchra shrub canopies at two locations near Toolik Lake, Alaska during the summer of 2012. The location of the PAR sensor and dataloggers were co-located with the LTER shrub plots (block 1 and 2), also used for the chamber flux and point frame measurements taken this same year.
Inorganic Nitrogen and phosphorus were analyzed on snow samples taken from two snow pits near the long-term acrtic LTER mesic acidic tussock experimental plots. The snow layers in each pit were described and sampled separtely with the help of Matthrew Sturm.
Phenological stages of deciduous plants were observed at a long term experimental moist acidic tussock tundra site (Arctic LTER) near Toolik Field Station, AK. Also, ITEX maximum growth measurements were recorded on August 19th (moist tussock tundra). Experimental treatments at each site included factorial NxP, greenhouse and shadehouse and were begun in 1989. See 96gspheg.html and 96gsphsg. html for phenological data on evergreen and sedge species.
Soil moisture and temperature were recorded at the Anaktuvuk River burn area during the summers from 2010 to 2013. Six sensors were deployed and measured temperature on half-hourly intervals over the summer and into the fall depending on battery function. Sensors were place in a hexagonal shape around a central datalogger. Note that over time sensor depths changed due to frost heave and other environmental factors. All data contained should be treated as suspect where sensors may have been at surface. These sensors were removed August 20, 2013, no replacement sensors were installed.
Soil moisture and temperature were recorded at the Anaktuvuk River burn area during the summers from 2010 to 2013. Six sensors were deployed and measured temperature on half-hourly intervals over the summer and into the fall depending on battery function. Sensors were place in a hexagonal shape around a central datalogger. Note that over time sensor depths changed due to frost heave and other environmental factors. All data contained should be treated as suspect where sensors may have been at surface. These sensors were removed August 23, 2013, no replacement sensors were installed.
Soil moisture and temperature were recorded at the Anaktuvuk River burn area during the summers from 2010 to 2013. Six sensors were deployed and measured temperature on half-hourly intervals over the summer and into the fall depending on battery function. Sensors were place in a hexagonal shape around a central data logger. Note that over time sensor depths changed due to frost heave and other environmental factors. All data contained should be treated as suspect where sensors may have been at surface. These sensors were removed August 20, 2013, no replacement sensors were installed.
Lake trout were analysed for carbon and nitrogen stable isotope values in 6 Arctic lakes near Toolik Lake at the Arctic LTER in 1987 and 1988. The fish were also analysed for age using otoliths.
This database contains soil and permafrost stratigraphy associated with thermokarst features near Toolik Lake and the Noatak River collected by Torre Jorgenson and Andrew Balser during summers 2009-2011. The Access Database has main data tables (tbl_) for site (environmental), soil stratigraphy, soil physical data, soil chemical data, soil isotopes (ground ice), soil radiocarbon dates, topography and bathymetry, and vegetation cover.
Above ground plant and below ground stem biomass were measured in 2011 from three sites at and around the Anaktuvuk River Burn: severely burned, moderately burned and unburned. These samples were analyzed for carbon and nitrogen concentrations.
A summary of below ground root biomass, carbon and nitrogen concentrations, measured at three sites at and around the Anaktuvuk River Burn: severely burned, moderately burned and unburned.
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.
Above ground plant and below ground stem biomass were measured in 2011 from three sites at and around the Anaktuvuk River Burn: severely burned, moderately burned and unburned. These samples were analyzed for carbon and nitrogen concentrations.
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.
Below ground root biomass was measured by depth increments at three sites at and around the Anaktuvuk River Burn: severely burned, moderately burned and unburned. Roots were also analyzed for carbon and nitrogen concentrations.
Above ground plant and below ground stem biomass were measured in 2011 from three sites at and around the Anaktuvuk River Burn: severely burned, moderately burned and unburned. These samples were analyzed for carbon and nitrogen concentrations.
Zooplankton density in number per liter for all samples collected from arctic lakes near Toolik Lake Field Station (Arctic LTER) in summer from 1983 to 1992 (inclusive). NOTE: The dates for 1992 are WRONG in versions 1 and 2. The original dates were entered in several date formats which resulted in conversion errors.
Zooplankton density in number per liter for all samples collected from arctic lakes near Toolik Lake Field Station (Arctic LTER) in the summer of 1977.
Pool size and d15N values for chloroform-extractable N, extractable-N, and non-extractable N pools. Samples collected in Aug. 2003 from 1st Organic Layer of 15N addition plots in Imnavait watershed.
1st Organic Layer = the upper 10 cm of organic soil or, if the organic layer was < 10 cm thick, the entire layer (e.g., there was never > 4 cm of organic soil at Crest).
Decadal file describing the physical lake parameters recorded at various lakes near Toolik Research Station during summers from 1975 to 1989. Depth profiles at the sites of physical measures were collected in situ. Values measured included temperature, conductivity, pH, dissolved oxygen, Chlorophyll A, Secchi disk depth and PAR. Note that some sample depths also have additional parameters measured and available in separate files for water chemistry and primary production.
Hydrolyzable N pool size and 15N atom % of natural and enriched soils collected from Imnavait watershed in summer of 2005.
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.
Average conductivity of the epilimnion (0-3m of water depth) found in Toolik Lake during the month of July.
Dataset includes rates of benthic gross primary productivity (GPP) in mmol O2/m2/d by irrandiance (I) in uE/m2/s curves and benthic respiration rates in mmol/m2/d from lakes E-5, E-6, Toolik, Fog Lake 2, Horn, Perched and Luna during the summer of 2009-2010.
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.
Methane and carbon dioxide emissions were monitored in control, greenhouse, and nitrogen and phosphorus fertilized plots of three different plant communities. This is the third year of collection data.
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 chlorophyll a and primary production in various lakes near Toolik Research Station (68 38'N, 149 36'W) during summers from 1983 to 1989. Sample site descriptors include an assigned number (sortchem), site, date of analysis (incubation), time, depth and rates of primary production. The amount of chlorophyll a and pheophytin were also measured.
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.
Methane and carbon dioxide emissions were monitored in control, greenhouse, and nitrogen and phosphorus fertilized plots of three different plant communities. This is the second year of collection data.
Methane and carbon dioxide emissions were monitored in control, greenhouse, and nitrogen and phosphorus fertilized plots of three different plant communities.
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.
Decadal file describing the chlorophyll a and primary production in various lakes near Toolik Research Station (68 38'N, 149 36'W) during summers from 2010 to 2020. Sample site descriptors include an assigned number (sortchem), site, date of analysis (incubation), time, depth and rates of primary production. The amount of chlorophyll a and pheophytin were also measured.
Decadal file describing the chlorophyll a and primary production in various lakes near Toolik Research Station (68 38'N, 149 36'W) during summers from 1990 to 1999. Sample site descriptors include an assigned number (sortchem), site, date of analysis (incubation), time, depth and rates of primary production. The amount of chlorophyll a and pheophytin were also measured.
Thaw depth was measured using a steel probe in the Imnavait Creek watershed, near Toolik Lake, Alaska. The thaw grid includes measurements made from the valley bottom (on both sides of the stream), up the hillslope to the hilltop (watershed boundary). The thaw grid is near Imnavait water tracks 7 and 8, and measurements have been made from the 2003 season until present. Two surveys are conducted each summer, on 2 July and on 11 August (plus or minus 1-2 days on either side of those dates).
Yearly file describing the metological conditions on Toolik Lake (named the Toolik Lake Climate station), adjacent to the Toolik Field Research Station (68 38'N, 149 36'W). This is a floating climate station and should not be confused with the Toolik Field Station Climate site (TFS Climate Station or Met Station) which is a terrestrial station (located on land). Note that this land station has been called the "Toolik Main Climate Station", and the station on the lake is located where the main lake sampling site is located so it has also been called the Toolik Lake Main Climate Station.
Yearly file describing the metological data on Lake E5 (Lake E5 Climate station) near the Toolik Field Research Station (68 38'N, 149 36'W). Measurements include air temperature, relative humidity, wind direction, and wind speed..
Thaw depth was measured since 1990 using a steel probe in the Tussock watershed just south of Toolik Lake, Alaska, on a gentle slope dominated by moist, non-acidic tussock tundra. At least two surveys are conducted each summer, on 2 July and on 11 August (plus or minus 1 day).
The Anaktuvuk River Fire occurred in 2007 on the North Slope of Alaska. In 2008, three eddy covariance towers were established at sites representing unburned tundra, moderately burned tundra, and severely burned tundra. Eriophorum vaginatum flowers were counted from annual photographs of each site during peak flowering season (6/17-7/20).
Dissolved organic carbon (DOC) measurements from Toolik Lake Inlet and Toolik Lake main sampling station for 2005-2008. The earliest measurements were in May and with the latest in September.
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).
Stream discharge, stage height, temperature, and conductivity of Toolik Inlet during the 2008 study season.