Arctic LTER Database

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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:2008_MCM_ARFsoilCN.05
Dataset Title: Characterization of burned and unburned moist acidic tundra soils for estimating C and N loss from the 2007 Anaktuvuk River Fire, sampled in 2008.
Investigator 1: 
First Name:Michelle
Last Name:Mack
Organization:University of Florida
Address line 2:220 Bartram Hall
Address line 3:Department of Biology
City:Gainesville
State:FL
Zip Code:32611
Country:USA
Associate Investigators:
Keywords:organic soil layer, depth, bulk density, carbon concentration, nitrogen, carbon pool, disturbance
Abstract: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. Together, these measurements were used to reconstruct pre-fire soil and plant carbon and nitrogen pools and estimate ecosystem losses of these elements during the fire.
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.10125&urlTail=burn/terrestrial/data/2008_MCM_ARFsoilCN.csv
Data File Name 2008_MCM_ARFsoilCN.xls
Beginning Date 6/25/2008
End Date 8/10/2008
Number of Data Records 1392
Other Files to Reference 2008_MCM_ARFsites.xls,2008_MCM_ARF14C.xls,2008_MCM_ARFloss.xls
Availability Status 1
Quality Control Information
Maintenance Description Version 1: checked and generated EML and Web files. Jim L 12Jul2011
Log of Changes: Version 2: Updated to newer metadata form (with sites sheet). CH March 2013.
Version3 corrected eml exel file name JimL 16May13
Version 5: Checked keywords against the LTER network preferred list and replaced non-preferred terms. Jim L 15Jan14
 
RESEARCH LOCATION:                  
Location Name Anaktuvuk River Fire Scar 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 Anaktuvuk River Fire scar (2007) and unburned sites Enter Description Enter Description Enter Description Enter Description Enter Description Enter Description Enter Description  
Location Bounding Box                  
West Bounding Coordinate -150.90848                
East Bounding Coordinate -148.72081                
North Bounding Coordinate 69.41152                
South Bounding Coordinate 68.62283                
OR if single point location                  
Latitude 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 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  
Link to Google Map                  
                   
 
TAXONOMIC COVERAGE:
Organisms studied Eriophorum vaginatum
 
Methods:A detailed methods supplement is available online (link here).


Field sites: Twenty MAT sites within the burn were accessed via helicopter from either Umiat or Toolik Lake in July and August of 2008 . Burn severity was mapped using the differenced Normalized burn Ratio (dNBR) method40 and sites 1-12 were randomly chosen to represent the range and frequency of dNBR values as described in Jones et al. (2009). The remaining sites, 13-20, were chosen randomly along hillslope transects from areas where collaborators had previously established eddy covariance towers and lake/stream monitoring.
 
To obtain empirical relationships between ecosystem structure and the element pools necessary for reconstruction of pre-fire soil C and N pools, 11 unburned MAT sites were also sampled . Samples from one unburned site (ARF109) were held back from analyses for testing the reconstruction method. Three unburned sites were adventitiously encountered within the burn perimeter, an additional site was located near the 2007 Kuparuk Fire (69.2974 °N, 150.3221 °W), and seven others were systematically selected along the Dalton Highway. The latter sites were randomly selected from a GIS database that included all MAT areas along the Dalton within the elevation and climate range of the burn scar and were allocated to span the same elevations as the burn scar. All sites were >300 m from the road to minimize the effects of dust and other disturbances41,42.
  
Field sampling—unburned sites: We quantified the relationship between E. vaginatum crowns and SOL depth or biomass, and characterized SOL bulk density and element concentration across the 11 unburned sites. Along a 50 m transect in each site, we measured the depth of thaw and SOL at 5 m intervals (random point) and directly adjacent to the tussock nearest to the random point (n=10 random and 10 tussock points). We measured at both random and tussock points to determine whether the relationship between soil organic matter depth and tussock crowns was related to distance to tussock. Thaw depth was measured by inserting a metal rod into the soil until it hit ice or rock (differentiated by the sound and texture of the hit), marking the surface of the green moss on the rod, removing it, and measuring the distance from the tip to the mark with a meter stick. Soil organic layer depth was measured by slicing a square pit with a serrated knife, removing a monolith of organic soil, exposing the surface of the mineral soil, and measuring the distance from the surface of the green moss to mineral soil on two sides of the pit. The two depth measurements per pit were averaged to yield one SOL depth measurement per point.
 
At each point where SOL depth was measured, we used two meter sticks attached at a sliding right angle and fitted with a tubular spirit level to measure the depth of the green moss below a plane parallel to the crown of the nearest E. vaginatum tussock . Use of the level ensured that the right angle was parallel to the crown and orthogonal to the ground. For the randomly located sample point, we also measured the distance to the nearest tussock using this apparatus. We measured the distance to, crown diameter of, and survivorship of the three next closest tussocks and used a nearest-neighbor method to estimate tussock density44. For each tussock, two crown diameter measurements were made (and averaged) at right angles by compressing the leaves and manually locating the sides of the crown.
 
To determine soil bulk density and element concentration, organic soil horizons were sampled volumetrically with a serrated knife. At 10 m intervals, a pit was dug and a 10 x 20 cm soil monolith was excised from the side of the pit, extending from the surface of the green moss to the surface of the mineral soil (roughly 5-30 cm depth depending on location). This monolith was wrapped in tinfoil to preserve structure, returned to the field station and frozen prior to shipping to the University of Florida (UF) for analyses of bulk density, moisture, C and N concentration, and C isotopes. All aboveground plant material attached to the surface of the soil monolith was included in the sampling. Tussocks were also harvested at 15 m intervals to develop allometric relationships between tussock diameter and combustible biomass (see below). Biomass was shaved from the live tussock with a serrated knife and returned to the field station, where it was dried at 70° C for 48 hours before weighing and shipping to UF for analyses of C and N concentration.
 
Field sampling—burned sites: Measurements in burned sites were similar to those in unburned sites except that measurements were made on the surface of the residual burned organic layer rather than the surface of the green moss and tussock leaves were not sampled.
 
Laboratory analyses: Approximately 155 soil monoliths comprising ~1000 individual 5 cm increment soil samples were collected in total from the 20 burned and 11 unburned sites. In the lab, each monolith was bisected depth-wise with an electric carving knife. One half of the monolith was processed for radiocarbon measurements, as described below, and re-frozen for archival purposes. In the remaining half, green moss and dwarf shrubs were sliced off and the remainder of the core was sliced into 5 cm depth intervals with the last sample of variable depth depending on the location of the organic/mineral interface. Samples were homogenized by hand and coarse organic materials (>2.5 cm twigs and roots) and rocks were removed. Coarse and fine organic fractions were weighed wet, dried at 70° C for 48 hours to determine dry matter content, then ground on a Wiley mill with a 40 mm sieve. Carbon and N content was measured on a Costech Elemental Analyzer (Costech Analytical, Los Angeles, California, USA) calibrated with the NIST peach leaves standard (SRM 1547, National Institute of Standards and Technology, Gaithersburg, MD, USA). The volume of each monolith layer was calculated as depth times area minus the volume of rocks. Bulk density, C or N pools were calculated for both fine and coarse organic fractions.

Literature Cited

40Key, C. H. and Benson, N. C., in Firemon: Fire effects monitoring and inventory system, edited by D. C. Lutes, R. E. Keane, J. F. Caratti et al. (USDA Forest Service, Rocky Mountain Monitoring and Inventory System, Ogden, UT, 2005), pp. 25-36.

41Walker, D. A. and Everett, K. R., Road dust and its environmental impact on Alaskan taiga and tundra. Arctic and Alpine Research 19, 479-489 (1987).

42Myers-Smith, I. H., Arnesen, B. K., Thompson, R. M., and Chapin, F. S., Cumulative impacts on Alaskan arctic tundra of a quarter century of road dust. Ecoscience 13 (4), 503-510 (2006).

44West, P. W., Tree and forest measurement, 2nd ed. (Springer-Verlag, Heidleberg, 2009).
 
 
 

Data Table

Variable Name Variable Description Data Type Units DateTime Format Code Information Missing Value Code
State Burned or unburned status of site text        
Site number Site number assigned in lab number number     .=Missing or Not Measured
Field code Field code used for site in field text        
Profile number Replicate soil profiles sampled within each site text        
Layer Description of layer text        
Depth bin Text entry describing depth increment text        
Depth bin code Numeric bin assigned to depth increment number number     .=Missing or Not Measured
Avg depth Average of three depths of increment measured in lab number centimeter     .=Missing or Not Measured
Type Size fraction of soil organic matter text        
%N Percentage N of dry mass number percent     .=Missing or Not Measured
%C Percentage C of dry mass number percent     .=Missing or Not Measured
Min? Identification of sample as mineral (and hence not included in calculations of organic layer pool size) number number     .=Missing or Not Measured
Bulk density (g/cm3) Dry mass per unit volume of soil (minus rock volume) number gramPerCentimeterCubed     .=Missing or Not Measured
gN/m2 Mass of nitrogen per meter squared number gramPerMeterSquared     .=Missing or Not Measured
gC/m2 Mass of carbon per meter squared number gramPerMeterSquared     .=Missing or Not Measured
CgN/m2 Corrected mass of nitrogen per meter squared. Depth is standardized to 5 cm depth for all increments except for the GM number gramPerMeterSquared     .=Missing or Not Measured
CgC/m2 Corrected mass of carbon per meter squared. Depth is standardized to 5 cm depth for all increments except for the GM number gramPerMeterSquared     .=Missing or Not Measured