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.
Data Set Results
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.
Vegetation indices calculated from reflectance spectra collected at Arctic LTER experimental plots at Toolik Lake, Alaska during the 2007-2019 growing seasons.
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.
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.
A spectrophotometer was used to scan the canopy vegetation of ITEX harvest plots. The resulting reflectance spectra were used to calculate several vegetation indices of interest (NDVI, EVI, EVI2, PRI, WBI, Chlorophyll Index). Average values of these vegetation indices for each ITEX harvest plot are presented here. These plots also had biomass harvests performed and were analyzed for leaf area and nitrogen content (see 2003-2009gsharvest.csv, 2003-2009gsharvestLAI-N.csv).
Soil temperature, moisture content and thaw depth of the ITEX flux survey plots. Survey plots were located in the Toolik Lake LTER fertilization experiment in Alaska; at Imnavait Creek, Alaska; at Paddus, Latnjajaure and the Stepps site near Abisko in northern Sweden; at various sites in Adventdalen, Svalbard; in the Zackenberg valley, Northeast Greenland; at BEO near Barrow, Alaska and at the Anaktuvuk River Burn in Alaska. Measurements were made during the growing seasons 2003 to 2009.
The Anaktuvuk River Fire occurred in 2007 on the North Slope of Alaska. In 2008, three eddy covariance towers were established at sites represent ing unburned tundra, moderately burned tundra, and severely burned tundra. Several times during the 2008-2014 growing seasons, thaw depth was measured at approximately 70 points near each of these towers . Data presented here are the individual measurements for each site and date.
Summary of three methods used to estimate the Leaf Area Index (LAI) of 19 1m x 1m plots sampled with a point frame near the LTER Shrub plots at the Toolik Field Station in AK the summer of 2012. The methods used were: (1) exponential relationship between LAI and NDVI as measured above the canopy with a Unispec spetroradiometer; (2) Delta-T SunScan canopy analyzer held at 5 cm above the ground under both direct and diffuse light conditions; (3) pin-drop point frame tequnique. Where values have been averaged (such as for the NDVI and SunScan measurements), the standard deviation is given.
Soil temperature at 5cm and 10cm depth [°C], volumetric water content (VWC) [%] and depth of thaw [cm] for 14 shrub canopy flux plots measured in vicinity of the Toolik Field Station, AK in 2012.
This file contains limited daily summaries of PAR, relative humidity, and temperature data monitored above, within, and below 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.
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.
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.
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.
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.
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.
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).
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.
A spectrophotometer was used to scan the canopy vegetation of ITEX flux plots. The resulting reflectance spectra were used to calculate several vegetation indices of interest (NDVI, EVI, EVI2, PRI, WBI, Chlorophyll Index). Average values of these vegetation indices for each ITEX flux plot are presented here.
Hourly weather data from the LTER Moist Acidic Tussock Experimental plots. The station was installed in 1990 in block 2 of the Toolik LTER experimental moist acidic tussock plots. The plots are located on a hillside near Toolik Lake (68 38' N, 149 36'W). Global solar radiation, photosynthetic active radiation, unfrozen precipitation, air temperature, relative humidity, wind speed, and wind direction are measured at 3 meters. Additional sensors in greenhouses and shade houses plots measure air temperature, relative humidity and photosynthetic active radiation during the growing season.
Hourly weather data from the LTER Moist Acidic Tussock Experimental plots. The station was installed in 1990 in block 2 of the Toolik LTER experimental moist acidic tussock plots. The plots are located on a hillside near Toolik Lake (68 38' N, 149 36'W). Global solar radiation, photosynthetic active radiation, unfrozen precipitation, air temperature, relative humidity, wind speed, and wind direction are measured at 3 meters.
Hourly weather data from the Arctic Tundra LTER site at Toolik Lake. The following parameters are measured every minute and averaged or totaled every hour; air temperature and relative humidity at 1 and 5 meters, wind speed at 1 and 5 meters, wind direction at 5 meters, global solar radiation, photosynthetically active radiation, net radiation (Fritschen type), barometric pressure, and unfrozen precipitation
Weather data files for Arctic Tundra LTER site at Toolik Lake, North Slope Alaska. Only the sensors that are measured every 10 minutes and averaged every three hours are include, i.e. soil temperatures, lake temperature, lake depth, and evaporation pan depth and pan water temperature.
Weather data file for Arctic Tundra LTER site at Toolik Lake. Only sensors measured every 10 minutes and averaged every three hours are include in this file, i.e. soil temperatures, lake temperature, lake depth, and evaporation pan depth and pan water temperature.
Weather data file for Arctic Tundra LTER site at Toolik Lake. Only the sensors that are measured every 10 minutes and averaged every three hours are include, i.e. soil temperatures, lake temperature, lake depth, and evaporation pan depth and pan water temperature.
Hourly weather data from the Arctic Tundra LTER site at Toolik Lake. The following parameters are measured every minute and averaged or totaled every hour: air temperature and relative humidity at 1 and 5 meters, wind speed at 1 and 5 meters, wind direction at 5 meters, global solar radiation, photosynthetically active radiation, barometric pressure, and unfrozen precipitation.
Hourly weather data from the Arctic Tundra LTER site at Toolik Lake. The following parameters are measured every minute and averaged or totaled every hour: air temperature and relative humidity at 1 and 5 meters, wind speed at 1 and 5 meters, wind direction at 5 meters, global solar radiation, photosynthetically active radiation, barometric pressure, and unfrozen precipitation.
Daily weather data file for Arctic Tundra LTER site at Toolik Lake. Included are daily averages and/or maximums and minimums of air, soil and lake temperature, wind speed, vapor pressure, and sum of global radiation and unfrozen precipitation recorded near Toolik Lake.
Daily weather data file for Arctic Tundra LTER site at Toolik Lake. Included are daily averages and/or maximums and minimums of air, soil and lake temperature, wind speed, vapor pressure, and sum of global radiation and unfrozen precipitation recorded near Toolik Lake.
Daily weather summaries from Toolik Field Station Meteorological Station, Toolik Lake, Alaska. Included are daily averages and/or maximums and minimums of air, soil and lake temperature, wind speed, vapor pressure, and sum of global radiation and precipitation recorded near Toolik Lake.
Daily weather summaries from Toolik Field Station Meteorological Station, Toolik Lake, Alaska. Included are daily averages and/or maximums and minimums of air, soil and lake temperature, wind speed, vapor pressure, and sum of global radiation and precipitation recorded near Toolik Lake.
Weather data file for Arctic Tundra LTER site at Toolik Lake. Only the sensors that are measured every 10 minutes and averaged every three hours are include, i.e. soil temperatures, lake temperature, lake depth, and evaporation pan depth and pan water temperature.
Daily weather data file for Arctic Tundra LTER site at Toolik Lake. Included are daily averages and/or maximums and minimums of air, soil and lake temperature, wind speed, vapor pressure, and sum of global radiation and unfrozen precipitation recorded near Toolik Lake.
Daily weather data file for Arctic Tundra LTER site at Toolik Lake. Included are daily averages and/or maximums
and minimums of air, soil and lake temperature, wind speed, vapor pressure, and sum of global radiation and unfrozen precipitation recorded near Toolik Lake.
Weather data file for Arctic Tundra LTER site at Toolik Lake. Only the sensors that are measured every 10 minutes and averaged every three hours are include, i.e. soil temperatures, lake temperature, lake depth, and evaporation pan depth and pan water temperature.
Hourly weather data from the Arctic Tundra LTER site at Toolik Lake. The following parameters are measured every minute and averaged or totaled every hour: air temperature and relative humidity at 1 and 5 meters, wind speed at 1 and 5 meters, wind direction at 5 meters, global solar radiation, photosynthetically active radiation, barometric pressure, and unfrozen precipitation.
Weather data file for Arctic Tundra LTER site at Toolik Lake. Only the sensors that are measured every 10 minutes and averaged every three hours are include, i.e. soil temperatures, lake temperature, lake depth, and evaporation pan depth and pan water temperature.
Hourly weather data from the Arctic Tundra LTER site at Toolik Lake. The following parameters are measured every minute and averaged or totaled every hour: air temperature and relative humidity at 1 and 5 meters, wind speed at 1 and 5 meters, wind direction at 5 meters, global solar radiation, photosynthetically active radiation, barometric pressure, and precipitation.
Hourly weather data from the Arctic Tundra LTER site at Toolik Lake. The following parameters are measured every minute and averaged or totaled every hour: air temperature and relative humidity at 1 and 5 meters, wind speed at 1 and 5 meters, wind direction at 5 meters, global solar radiation, photosynthetically active radiation, barometric pressure, and unfrozen precipitation.
Daily weather data file for Arctic Tundra LTER site at Toolik Lake. Included are daily averages and/or maximums and minimums of air, soil and lake temperature, wind speed, vapor pressure, and sum of global radiation and unfrozen precipitation recorded near Toolik Lake.
Weather data file for Arctic Tundra LTER site at Toolik Lake. Only the sensors that are measured every 10 minutes and averaged every three hours are include, i.e. soil temperatures, lake temperature, lake depth, and evaporation pan depth and pan water temperature.
Daily weather data file for Arctic Tundra LTER site at Toolik Lake. Included are daily averages and/or maximums and minimums of air, soil and lake temperature, wind speed, vapor pressure, and sum of global radiation and unfrozen precipitation recorded near Toolik Lake.
Daily weather data file for Arctic Tundra LTER site at Toolik Lake. Included are daily averages and/or maximums and minimums of air, soil and lake temperature, wind speed, vapor pressure, and sum of global radiation and unfrozen precipitation recorded near Toolik Lake.
Weather data file for Arctic Tundra LTER site at Toolik Lake. Only the sensors that are measured every 10 minutes and averaged every three hours are include, i.e. soil temperatures, lake temperature, lake depth, and evaporation pan depth and pan water temperature.
Daily weather data file for Arctic Tundra LTER site at Toolik Lake. Included are daily averages and/or maximums and minimums of air, soil and lake temperature, wind speed, vapor pressure, and sum of global radiation and unfrozen precipitation recorded near Toolik Lake.
Weather data file for Arctic Tundra LTER site at Toolik Lake. Only the sensors that are measured every 10 minutes and averaged every three hours are include, i.e. soil temperatures, lake temperature, lake depth, and evaporation pan depth and pan water temperature.
Hourly weather data from the Arctic Tundra LTER site at Toolik Lake. The following parameters are measured every minute and averaged or totaled every hour: air temperature and relative humidity at 1 and 5 meters, wind speed at 1 and 5 meters, wind direction at 5 meters, global solar radiation, photosynthetically active radiation, barometric pressure, and unfrozen precipitation.
Weather data file for Arctic Tundra LTER site at Toolik Lake. Only the sensors that are measured every 10 minutes and averaged every three hours are include, i.e. soil temperatures, lake temperature, lake depth, and evaporation pan depth and pan water temperature.