Soil stratification was determined by measuring the vertical thickness of three main strata (surface acrotelm, mid-depth catotelm, and bottom mineral soil) found in organic-rich or peat soils in the Toolik Lake region, North Slope of Alaska. Additional data for each site include dominant vegetation, landscape position, glacial surface, and microtopography.
Data Set Results
Displaying 451 - 479 of 479
Soil cores of 5 cm diameter down to frozen
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 p
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 photodegradation of carboxyl carbon (C) within permafrost DOC was quantified by 13C nuclear magnetic resonance (NMR).
Soils were collected from the frozen permafrost layer (greater than 60 cm below the surface) at six sites underlying tussock or wet sedge vegetation, and on three glacial surfaces on the North Slope of Alaska during the summers of 2015 and 2018. Dissolved organic carbon (DOC) was leached from each permafrost soil and the water chemistry was analyzed.
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.
Eriophorum vaginatum flower counts from annual photographs at the severe, moderate, and unburned Anaktuvuk River, Alaska, USA flux tower sites during
This file contains leaf area index (LAI) measurements from an nitrogen (N), phosphorus (P)
This file contains point-frame measurements from a
Files used to generate the data for figures in:
Rastetter, EB, Kling, GW, Shaver, GR, Crump, BC, Gough, L. Ecosystem Recovery from Disturbance Is Constrained by N Cycle Openness, Vegetation-Soil N Distribution, Form of N Losses, and the Balance between Vegetation and Soil-Microbial Processes. Ecosystems (2020). https://doi.org/10.1007/s10021-020-00542-3.
We deployed three eddy covariance towers along a burn severity gradient (i.e.
We deployed three eddy covariance towers along a burn severity gradient (i.e.
We deployed three eddy covariance towers along a burn severity gradient (i.e.
Stream temperature and discharge measured each summer for Roche Moutonnee Creek and Trevor Creek. Dataloggers measured stream temperature and stream height at regular intervals. Stream height is converted into stream discharge based on a rating curve calculated from manual discharge measurements throughout the season. The principal investigator in charge of the temperature and discharge measurements is Dr. Breck Bowden.
Vegetation (species) abundances were measured from LTER heath tundra herbivore exclosures using the point frame method. This file contains the number of pin hits per species for each subplot.
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 temperature data from the 1989 LTER Moist Acidic Tussock (MAT89) Experimental plots. The logging station was installed in 1990 in block 2 of a four block experimental block design. The plots are located on a hillside near Toolik Lake (68 38' N, 149 36'W). Two replicates depth profiles (10, 20 ,40 centimeters) were installed in each block 2 experimental plots. Frost heaving has caused uncertain depths of measurements for many of the profiles. This data set contains only the control profiles from 2008 to 2020.
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 .
This file contains leaf area index (LAI) based on biomass measurements from an aboveground pluck in the southern portion of the Anaktuvuk River fire scar, and a nearby unburned site in late July 2017. Vegetation was sampled randomly at 10-m intervals along two 100 meter transects at both the burned and unburned sites. Vegetation was sampled within a 10X40 cm quadrat to the mineral layer, and plant material was sorted into new and old aboveground leaf and woody biomass by species.
This file contains maximum plant heights from point frame measurements made in the southern section of the 2007 Anaktuvuk River fire scar, at a severely burned site and a nearby unburned site. Pin-vegetation contact was recorded using a 0.56 m2 frame with 41 evenly spaced sampling points. Data were collected during peak green in summer 2019.
Tillers from 24 Eriophorum vaginatum individuals were sampled in late July 2019 to examine differences in percent nitrogen between previously burned (Anaktuvuk River Fire) and unburned tussocks at a nearby unburned control site. At the burned site tussocks exhibiting evidence of rodent grazing were also sampled to separate herbivore effects from those of the fire. From each tussock, 3-4 new leaves were sampled (as indicated by lack of brown tips) and dried at 60°C for 24 hours, before being ground and analyzed for percent nitrogen.
This file contains Eriophorum vaginatum rhizome biomass from a 2017 biomass pluck of previously burned tundra (2007 Anaktuvuk River Fire) and nearby unburned tundra. Rhizome biomass from the pluck was combined with rhizome percent nitrogen estimates (2.47% at the Anaktuvuk River Fire, and 1.05% at the nearby unburned site) to estimate grams of nitrogen per meter squared, to evaluate differences in winter forage quality for the rodent herbivore, Microtus oeconomus. Percent nitrogen estimates were derived from pooled rhizome samples collected from the two sites in late 2018.
Weather measurements from the Toolk Main weather station, 1989-2019. This data was originally downloaded from the Toolik Field Station Environmental Data Center March 8, 2021.
This climate record was used in Rastetter et al., Science, submitted.
The latest climate data is available at http://toolik.alaska.edu/edc/abiotic_monitoring/data_query.php