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
Data file describing the apparent quantum yield of photo-oxidation, photo-mineralization, and photo-stimulated microbial respiration of dissolved organic carbon in water samples collected at various sites near Toolik Lake on the North Slope of Alaska. A synthesis of the data presented here is published in Cory et al. 2013, PNAS 110:3429-3434, and in Cory et al. 2014, Science 345:925-928.
Data file containing optical characterization of colored dissolved organic matter (CDOM). Data include CDOM absorption coefficients, water column light attenuation coefficients, specific UV light absorbance (SUVA254), spectral slope ratio, and fluorescence index from waters near Toolik Lake on the North Slope of Alaska. A synthesis of the data presented here is published in Cory et al. 2013, PNAS 110:3429-3434, and in Cory et al. 2014, Science 345:925-928.
Data file describing the biogeochemistry of samples collected at various sites near Toolik Lake on the North Slope of Alaska. Sample site descriptors include a unique assigned number (sortchem), site, date, time, depth, and category (level of thermokarst disturbance). Physical measures collected in the field include temperature, electrical conductivity, and pH.
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.
Weekly growth of plant species of three growth forms were measured in the ninth year of a long-term experiment at Toolik Field Station. The experimental treatments excluded small and large mammalian herbivores and increased soil nutrients in two arctic Alaskan tundra communities: moist acidic tussock and dry heath. This data set reports the deciduous dwarf shrub species. Please see 2004lggrgram for the tussock-forming and rhizomatous graminoid species growth data.
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.
Foliar nutrients (N, P, K, Ca, Mg, Al) for dominant species on moist acidic and non-acidic tundra, Arctic LTER, Toolik Field Station , Alaska, 1999.
Weekly growth of plant species of three growth forms were measured in the ninth year of a long-term experiment at Toolik Field Station. The experimental treatments excluded small and large mammalian herbivores and increased soil nutrients in two arctic Alaskan tundra communities: moist acidic tussock and dry heath. This data set reports the four graminoid (both tussock and rhizomatous forms) species. Please see 2004lggrbnan for Betula nana (dwarf shrub) growth data.
Foliar and litter nutrients and retranslocation efficiencies (N, P, K, Ca, Mg) for dominant species on moist acidic and non-acidic tundra, Arctic LTER, Toolik Field Station , Alaska, 1999.
These data are from two remote field campaigns in the Noatak National Preserve. Various thermokarst features and their receiving streams were sampled and characterized. A suite of water chemistry (nutrients, major anions and cations, total suspended sediment) and benthic variables (particulate carbon, nitrogen and phosphorus, and chlorophyll-a) were measured at 6 major sites (2 in 2010 and 4 in 2011). There were additional sites sampled for water chemistry above and below thermokarst features in 2011.
Water samples were taken at 5 locations at both I-Minus2 and Toolik River thermokarst sites (10 sampling locations total). A combination of ISCO and manual grab samples were taken depending on the sampling location and year.
Surface organic and mineral soil layers were sampled in retrogressive thaw slump disturbance scars and nearby undisturbed tundra to estmate the influence of this thermo-erosional--thermokarst--disturbance type on soil carbon (C) and nitrogen (N) pools. Within six independent sites, we identified multiple thaw slump scars and determined time after disturbance for each scar by (1) aging the population of tall deciduous shrubs rooted in the mineral soil and (2) by dating the basal layer of the re-accumulating soil organic matter.
The (ARCSSTK) did extensive research during 2009-2011 field seasons in Arctic Alaska. The objective of this data set was to measure the quantity and biodegradability of DOC from headwater streams and rivers across three geographic regions and across four natural ‘treatments’ (reference; thermokarst-; burned-, and thermokarst + burned-impacted streams) to evaluate which factors most strongly influence DOC quantity and biodegradablity at a watershed scale.
The (ARCSSTK) did extensive research during 2009-2011 field seasons in Arctic Alaska. The objective of this data set was to measure the quantity and biodegradability of DOC from headwater streams and rivers across three geographic regions and across four natural ‘treatments’ (reference; thermokarst-; burned-, and thermokarst + burned-impacted streams) to evaluate which factors most strongly influence DOC quantity and biodegradablity at a watershed scale. This table provides physical site characteristics for the locations sampled for stream water biodegradability.
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 Artic Stream Systems (CSASN) was active from 2010 to 2012. The CSASN goal was to quantify the relative influences of throughflow, 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. There were a number of TASCC and Plateau nutrient additions at each sampling location.
The Changing Seasonality of Arctic Stream Systems (CSASN) did extensive arctic stream research from 2010 to 2012. Specifically, 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 determine how these influences will shift under seasonal conditions that are likely to be substantially different in the future. Throughout the project, samples were collected from Benthic Rock Scrubs and Fine Benthic Organic Matter (FBOM).
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. There were a number of TASCC and Plateau nutrient additions at each sampling location.
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 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. There were a number of tracer addition for spiraling curve characterization (TASCC) and Plateau nutrient additions at each sampling location.
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. Throughout the project, samples were collected from Benthic Rock Scrubs and measured for cholorophyll-a and particulate carbon (C), nitrogen (N) and phosphorus (P).
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.
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.
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.
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.
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.
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.
Phenological stages of sedges were observed at a long term experimental moist tussock tundra site and a long-term experimental wet sedge tundra sites near Toolik Lake, 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 96gsphdc.html and 96gsphsg.html for phenological data on deciduous and evergeen species.
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.
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.
Above ground plant and below ground stem biomass was measured 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. Leaf areas were also measured for each quadrat but are in a separate file.
Biomass in tussock tundra experimental plots near Toolik Lake, North Slope, AK (68 degrees 38N, 149derees 34W). There were five harvests in 1983. This file is the May 21-22, 1983 harvest.
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).
This data file contains the data on weights and lengths from retrospective growth analysis of different stem age classes of Betula nana ramets from the LTER Nutrient and Warming manipulations in tussock tundra at Toolik Lake.
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 summaries for control and fertilized plots. Leaf area data is in 2000gsttLA
Above ground plant biomass and leaf area were measured in a moist acidic tussock tundra experimental site. The plots were set up in 1981 and have been harvested in periodical (See Shaver and Chapin Ecological Monographs, 61(1), 1991 pp.1-31. Mack, et al, Nature 2004 431:440-443) This file contains the biomass numbers for each harvested quadrat and per cent carbon and nitrogen summaries for harvests through 2000. Leaf area data is presented in other data files (see http://ecosystems.mbl.edu/arc).
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.
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.