Arctic LTER Database

Conditions of Use

The re-use of scientific data has the potential to greatly increase communication, collaboration and synthesis within and among disciplines, and thus is fostered, supported and encouraged. Permission to use this dataset is granted to the Data User free of charge subject to the following terms:

1) Acceptable use. Use of the dataset will be restricted to academic, research, educational, government, recreational, or other not-for-profit professional purposes. The Data User is permitted to produce and distribute derived works from this dataset provided that they are released under the same license terms as those accompanying this Data Set. Any other uses for the Data Set or its derived products will require explicit permission from the dataset owner.
2 ) Redistribution. The data are provided for use by the Data User. The metadata and this license must accompany all copies made and be available to all users of this Data Set. The Data User will not redistribute the original Data Set beyond this collaboration sphere.
3 ) Citation. It is considered a matter of professional ethics to acknowledge the work of other scientists. Thus, the Data User will properly cite the Data Set in any publications or in the metadata of any derived data products that were produced using the Data Set. Citation should take the following general form: Creator, Year of Data Publication, Title of Dataset, Publisher, Dataset identifier. For example:

Shaver, G. 1989. Above ground biomass in acidic tussock tundra experimental site, 1989, Arctic LTER, Toolik, Alaska. Arctic LTER, Marine Biological Lab, Woods Hole, Ma 02543. 1989gsttbm http://ecosystems.mbl.edu/arc/terrest/biomass/index.shtml 

4 ) Acknowledgement. The Data User should acknowledge any institutional support or specific funding awards referenced in the metadata accompanying this dataset in any publications where the Data Set contributed significantly to its content. Acknowledgements should identify the supporting party, the party that received the support, and any identifying information such as grant numbers. For example:

Data sets were provided by the Arctic LTER. This material is based upon work supported by the National Science Foundation under Grants #DEB-981022, 9211775, 8702328; #OPP-9911278, 9911681, 9732281, 9615411, 9615563, 9615942, 9615949, 9400722, 9415411, 9318529; #BSR 9019055, 8806635, 8507493.

5 ) Notification. The Data User will notify the Data Set Contact when any derivative work or publication based on or derived from the Data Set is distributed. The Data User will provide the data contact with two reprints of any publications resulting from use of the Data Set and will provide copies, or on-line access to, any derived digital products. Notification will include an explanation of how the Data Set was used to produce the derived work.
6 ) Collaboration. The Data Set has been released in the spirit of open scientific collaboration. Data Users are thus strongly encouraged to consider consultation, collaboration and/or co-authorship with the Data Set Creator.

By accepting this Data Set, the Data User agrees to abide by the terms of this agreement. The Data Owner shall have the right to terminate this agreement immediately by written notice upon the Data User's breach of, or non-compliance with, any of its terms. The Data User may be held responsible for any misuse that is caused or encouraged by the Data User's failure to abide by the terms of this agreement.

Disclaimer

While substantial efforts are made to ensure the accuracy of data and documentation contained in this Data Set, complete accuracy of data and metadata cannot be guaranteed. All data and metadata are made available "as is". The Data User holds all parties involved in the production or distribution of the Data Set harmless for damages resulting from its use or interpretation.

Dataset URLs:METADATA: HTML, Rich Text, XML(EML compliant)
DATA: Comma Delimited, Excel file with Metadata and data, Dataset via LTER Data Poral
Dataset ID:2012ARFluxModerate.03
Dataset Title:Anaktuvuk River Burn Eddy Flux Measurements, 2012 Moderate Burn Site, North Slope Alaska
Investigator 1: 
First Name:Gus
Last Name:Shaver
Organization:MBL
Address line 2:7 MBL St.
Address line 3:
City:Woods Hole
State:MA
Zip Code:02543
Country:USA
Investigator 2: 
First Name:Adrian
Last Name:Rocha
Organization:University of Notre Dame
Address line 2:Department of Biological Sciences
City:Notre Dame
State:IN
Zip Code:46556
Country:USA
Associate Investigators:
Keywords:net ecosystem exchange, energy and mass exchange, heat flux, Anaktuvuk River fire, burns, AON, disturbance, eddy flux, carbon dioxide fluxes
Abstract: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.
For questions about the Metadata and data contact the Investigators.
For information about this web site contact:
Arctic LTER Information Manager
The Ecosystems Center
Marine Biological Lab
7 MBL St
Woods Hole, MA 02543
Phone (508) 289 7496
Email: arc_im@mbl.edu
Online URL: http://ecosystems.mbl.edu/ARC/
DATA FILE INFORMATION:
Data File URL http://metacat.lternet.edu/das/dataAccessServlet?docid=knb-lter-arc.10348&urlTail=burn/terrestrial/data/2012ARFluxModerate.csv
Data File Name 2012ARFluxModerate.csv
Beginning Date 1/1/2012
End Date 12/31/2012
Number of Data Records 17568
Other Files to Reference
Availability Status Type 1
Quality Control Information
Maintenance Description Data collection and processing is complete
Log of Changes: Version 1, Sept 2013: Initial data release
Version 2: Checked keywords against the LTER network preferred list and replaced non-preferred terms. Jim L 15Jan14
Version 3: Missing value code corrected: NAN should be NaN. Jim L 24Jan14
 
RESEARCH LOCATION:                                            
Location Name Moderate burn flux tower Select Site or enter New One Select Site or enter New One Select Site or enter New One Select Site or enter New One Select Site or enter New One Select Site or enter New One Select Site or enter New One Select Site or enter New One Select Site or enter New One Select Site or enter New One Select Site or enter New One Select Site or enter New One Select Site or enter New One Select Site or enter New One Select Site or enter New One Select Site or enter New One Select Site or enter New One Select Site or enter New One Select Site or enter New One Select Site or enter New One  
Geographic Description Moderate burn flux tower site Anaktuvuk River burn, North Slope, Alaska Enter Description Enter Description Enter Description Enter Description Enter Description Enter Description Enter Description Enter Description Enter Description Enter Description Enter Description Enter Description Enter Description Enter Description Enter Description Enter Description Enter Description Enter Description Enter Description Enter Description  
Location Bounding Box                                            
West Bounding Coordinate                                            
East Bounding Coordinate                                            
North Bounding Coordinate                                            
South Bounding Coordinate                                            
OR if single point location                                            
Latitude 68.95 In Decimal Degrees In Decimal Degrees In Decimal Degrees In Decimal Degrees In Decimal Degrees In Decimal Degrees In Decimal Degrees In Decimal Degrees In Decimal Degrees In Decimal Degrees In Decimal Degrees In Decimal Degrees In Decimal Degrees In Decimal Degrees In Decimal Degrees In Decimal Degrees In Decimal Degrees In Decimal Degrees In Decimal Degrees In Decimal Degrees  
Longitude -150.21 In Decimal Degrees In Decimal Degrees In Decimal Degrees In Decimal Degrees In Decimal Degrees In Decimal Degrees In Decimal Degrees In Decimal Degrees In Decimal Degrees In Decimal Degrees In Decimal Degrees In Decimal Degrees In Decimal Degrees In Decimal Degrees In Decimal Degrees In Decimal Degrees In Decimal Degrees In Decimal Degrees In Decimal Degrees In Decimal Degrees  
Elevation In Meters In Meters In Meters In Meters In Meters In Meters In Meters In Meters In Meters In Meters In Meters In Meters In Meters In Meters In Meters In Meters In Meters In Meters In Meters In Meters In Meters  
Link to Google Map View on Google Map                                          
                                             
 
TAXONOMIC COVERAGE:
Organisms studied
 
Methods:We deployed three eddy covariance towers with identical instrumentation across a burn severity gradient (Rocha and Shaver 2009). The three sites (i.e. Severe burn, Moderate burn, and Unburned) were 40 km to the west of the nearest road and were selected during a helicopter survey of the southern area of the Anaktuvuk River Fire scar in late May 2008 (Figure 1; Table 1). Because the fire had burned through September of the previous year, initial deployment of flux towers occurred prior to any significant vegetative regrowth, and our sampling campaign captured the full 2008 growing season (June 1-August 28). Each site was equipped with a Campbell Scientific® CR5000 datalogger that recorded data from micrometeorological instrumentation located on a stainless steel tripod (CM110; Campbell Scientific; Logan Utah, USA) at a height of 2.6 m. Data were stored on a 2 Gb PCMCIA card and downloaded every two to three weeks. Power for the datalogger and instrumentation was located 15 m to the east or west of the tower and consisted of a south-facing solar panel and two 12 V 80 amp-hour batteries enclosed in a polyethylene box. Towers ran continuously through the summer of 2008 with the exception of the severe burn site, which was damaged by a bear during the last week of August. The towers have been in operation since June 2008.

Environmental data were recorded as half hour averages. Net radiation was monitored with a NRLITE net radiometer (Campbell Scientific; Logan Utah, USA). Incoming and reflected solar and longwave radiation were measured with a CNR-1 Radiometer (Campbell Scientific; Logan Utah, USA), while incoming and reflected Photosynthetically Active Radiation (PAR) were measured with a silicon quantum sensor (LI-COR; Lincoln, NE, USA). Air temperature and relative humidity was measured with an HMP45C-L sensor (Campbell Scientific; Logan Utah, USA) enclosed in a naturally aspirated radiation shield, while precipitation was measured with a tipping bucket rain gauge (TE525; Campbell Scientific; Logan Utah, USA). Volumetric water content at a depth of 2.5 cm was measured with two reflectometers (CS616; Campbell Scientfic; Logan Utah, USA), soil temperature at a depth of 2 and 6 cm was measured with two averaging soil thermocouples (TCAV-L; Campbell Scientific; Logan, Utah, USA), and soil heat flux at a depth of 8 cm was measured with four soil heat flux plates (HFP01; Campbell Scientific; Logan, Utah, USA). Measurements of the soil environment were recorded on separate CR1000 dataloggers at the severely and moderately burned sites.

Turbulent fluxes of momentum, sensible heat, latent heat and CO2 were determined by the eddy covariance technique (Baldocchi et al. 1988). Half hourly CO2 and H2O fluxes were calculated as the covariance between the turbulent departures from the mean of the 10 Hz vertical wind speed measured with a 3D sonic anemometer (CSAT3; Campbell Scientific; Logan, Utah, USA) and the CO2 and H2O mixing ratio measured with an open path InfraRed Gas Analyzer (IRGA; LI7500; LI-COR; Lincoln, NE, USA). Fluxes were processed using EdiRe software (University of Edinburgh; Moncrieff et al. 1997) and reported using the meteorological sign convention where negative NEE indicates carbon uptake and positive NEE indicates carbon loss from the ecosystem. Ten Hz data were despiked, rotated to the mean wind streamlines, and corrected for the density effect due to sensible heat transfer (i.e. WPL correction; Webb et al. 1980). Turbulent fluxes of sensible and latent heat captured 78 to 80% of the available energy at each of the sites, which is consistent with energy budget closure observed for other eddy covariance studies (Wilson et al. 2002).

The moderate burn site is comprised of a mosaic of partially and completely burnt moss patches scattered across the landscape that varied in size from ~1 to 10 m2. Partially burnt moss cover was 33% and was dominated by Sphagnum [Sphagnum spp.] and feather mosses [Hylocomium spp.]. Recovering and dead tussocks formed the dominant canopy cover. Intertussock area was composed of burnt duff (30% of ground cover) and several herbaceous species (Cloudberry; Labrador tea, and Cranberry [Vaccinium vitis-idaea L.]). All tussocks were scorched in the fire and 95% of tussocks recovered after the first growing season.

References:
Rocha, A.V. and G.R. Shaver (2009) Advantages of a two band EVI derived from solar and photosynthetically active radiation fluxes. Agricultural and Forest Meteorology. 149:1560-1563, doi:10.1016/j.agrformet.2009.03.016.

Rocha, A.V. and G.R. Shaver (2011) Burn severity influences post-fire CO2 exchange in arctic tundra. Ecological Applications. 21:477-489.

Rocha, A.V. and G.R. Shaver (2011) Postfire energy exchange in arctic tundra: the importance and climatic implications of burn severity. Global Change Biology. doi:10.1111/j.1365-2486.2011.02441.x.

Data Table

Variable Name Variable Description Data Type Units DateTime Format Code Information Missing Value Code
Year Year number number      
DOY Unitless Fractional Day of Year from January 1, 2008 number number      
Pressure Atmospheric pressure number kilopascal     NaN=MISSING OR NOT MEASURED
Air Temperature Air temperature at 2.6m number celsius     NaN=MISSING OR NOT MEASURED
Surface Temperature (Apogee) Kelvin degrees at surface number kelvin     NaN=MISSING OR NOT MEASURED
Soil Temperature Soil Temperature-Average of 2cm and 6cm measurements number celsius     NaN=MISSING OR NOT MEASURED
Ambient Vapor Pressure Ambient Vapor Pressure number kilopascal     NaN=MISSING OR NOT MEASURED
Incoming Shortwave Incoming Shortwave number wattPerMeterSquared     NaN=MISSING OR NOT MEASURED
Outgoing Shortwave Outgoing Shortwave number wattPerMeterSquared     NaN=MISSING OR NOT MEASURED
Incoming Longwave Incoming Longwave number micromolePerMeterSquaredPerSecond     NaN=MISSING OR NOT MEASURED
Outgoing Longwave Outgoing Longwave number micromolePerMeterSquaredPerSecond     NaN=MISSING OR NOT MEASURED
Net Radiation Net Radiation number wattPerMeterSquared     NaN=MISSING OR NOT MEASURED
Incoming PAR Incoming photosynthetically active radiation number micromolePerMeterSquaredPerSecond     NaN=MISSING OR NOT MEASURED
Outgoing PAR Outgoing photosynthetically active radiation number micromolePerMeterSquaredPerSecond     NaN=MISSING OR NOT MEASURED
IRGA AGC Count of IRGA AGC flag number number     NaN=MISSING OR NOT MEASURED
Friction Velocity Calculated friction velocity number meterSquaredPerSecond     NaN=MISSING OR NOT MEASURED
Wind Direction Sonic pointed North number degree     NaN=MISSING OR NOT MEASURED
Wind Speed Wind Speed number meterPerSecond     NaN=MISSING OR NOT MEASURED
Latent Heat Flux Latent Heat Flux number wattPerMeterSquared     NaN=MISSING OR NOT MEASURED
Sensible Heat Flux Sensible Heat Flux number wattPerMeterSquared     NaN=MISSING OR NOT MEASURED
Ground Heat Flux Ground Heat Flux number wattPerMeterSquared     NaN=MISSING OR NOT MEASURED
Net Ecosystem Exchange of CO2 Net Ecosystem Exchange of CO2 number micromolePerMeterSquaredPerSecond     NaN=MISSING OR NOT MEASURED