Arctic Vegetation Plots ATLAS Project North Slope and Seward Peninsula, AK, 1998-2000

This data set provides environmental, soil, and vegetation data collected from study sites on the North Slope and Seward Peninsula of Alaska during the Arctic Transition in Land-Atmosphere System (ATLAS) project. ATLAS-1 sites on the North Slope, located in Barrow, Atqasuk, Oumalik, and Ivotuk, were sampled in 1998-1999. ATLAS-2 sites located at Council and Quartz Creek on the Seward Peninsula were sampled in 2000. Specific attributes include dominant vegetation species and cover, biomass, soil chemistry and moisture, leaf area index (LAI), normalized difference vegetation index (NDVI), topography and elevation, and plant cover abundance.

Grids were subjectively established at all sites. Some of the grids were in homogeneous stands of vegetation that were considered representative of the regional climate or zonal vegetation. Other grids were in stands of vegetation that were regionally extensive. The source species observations and environmental samples were obtained from homogeneous plots/relevés within the grids and at other selected locations. In some cases where the vegetation was more heterogeneous, as for example in patterned ground, areas with frost boils, stone stripes, or closely spaced water tracks, samples were divided into representative microhabitats with each relevé representing a microsite within the grid.

There are 13 data files in comma-separated (.csv) format with this data set.

This data set provides environmental, soil, and vegetation data collected from study sites on the North Slope and Seward Peninsula of Alaska during the Arctic Transition in Land-Atmosphere System (ATLAS) project. ATLAS-1 sites on the North Slope, located in Barrow, Atqasuk, Oumalik, and Ivotuk, were sampled in 1998-1999. ATLAS-2 sites located at Council and Quartz Creek on the Seward Peninsula were sampled in 2000. Specific attributes include dominant vegetation species and cover, biomass, soil chemistry and moisture, leaf area index (LAI), normalized difference vegetation index (NDVI), topography, and elevation, and plant cover abundance. All data were not collected at all grids.

Grids were subjectively established at all sites. Some of the grids were in homogeneous stands of vegetation that were considered representative of the regional climate or zonal vegetation. Other grids were in stands of vegetation that were regionally extensive. The source species observations and environmental samples were obtained from homogeneous plots/relevés within the grids and at other selected locations. In some cases where the vegetation was more heterogeneous, as for example in patterned ground, areas with frost boils, stone stripes, or closely spaced water tracks, samples were divided into representative microhabitats with each relevé representing a microsite within the grid.

The Pre-ABoVE vegetation plot datasets were curated to create the Alaska Arctic Vegetation Archive (AVA-AK; Walker et al. 2016b, Walker 2013). The AVA-AK is a regional database that is part of the larger Arctic Vegetation Archive (Walker 2016a, Walker et al. 2013, Walker and Raynolds 2011).  The database contains vegetation plots from homogeneous plant communities with tables of cover or cover-abundance scores for all species and accompanying environmental site data.  Field data were collected using Braun-Blanquet, US National Vegetation Classification protocols, or comparable methods.

Project: Arctic-Boreal Vulnerability Experiment (ABoVE)

The Arctic-Boreal Vulnerability Experiment (ABoVE) iis a NASA Terrestrial Ecology Program field campaign that will take place in Alaska and western Canada between 2016 and 2021. Climate change in the Arctic and Boreal region is unfolding faster than anywhere else on Earth. ABoVE seeks a better understanding of the vulnerability and resilience of ecosystems and society to this changing environment.

Related data sets:

Pre-ABoVE: Arctic Vegetation Plots at Barrow, Alaska, 2012. ORNL DAAC, Oak Ridge, Tennessee, USA. https://doi.org/10.3334/ORNLDAAC/1505

Pre-ABoVE: Arctic Vegetation Plots, Oumalik, Alaska, 1983-1985. ORNL DAAC, Oak Ridge, Tennessee, USA. https://doi.org/10.3334/ORNLDAAC/1506

Pre-ABoVE: Arctic Vegetation Plots at Atqasuk, Alaska, 1975, 2000, and 2010. ORNL DAAC, Oak Ridge, Tennessee, USA. http://dx.doi.org/10.3334/ORNLDAAC/1371

Acknowledgements:

These data files were edited by Donald A. Walker, Amy L. Breen and Lisa A. Druckenmiller at the University of Alaska Fairbanks' Alaska Geobotany Center and obtained via the Arctic Geoecological Atlas (http://arcticatlas.geobotany.org/), which provides access to existing Arctic vegetation plot and map data in support of the ABoVE campaign.  

Spatial Coverage: North Slope and Seward Peninsula, Alaska

ABoVE Grid Locations:

             North Slop sites, ATLAS-1 sites: Ahh1Avv0Bh0Bv0

            Seward Peninsula, ATLAS-2 sites: Ahh0Avv0Bh0Bv0

Spatial Resolution: Point resolution

Temporal Coverage: 19980701 to 20000729

Temporal Resolution: Annual

Study Area (These coordinates are the approximate locations of the study sites and may not match the extents of data files. All latitude and longitude given in decimal degrees.)

Site	Westernmost Longitude	Easternmost Longitude	Northernmost Latitude	Southernmost Latitude
Atqasuk	-157.41238	-157.34555	70.46432	70.44332
Barrow	-156.608	-156.608	71.32193	71.32193
Oumalik	-156.02	-155.899	69.86229	69.83724
Ivotuk	-155.744	-153.738	68.48702	68.47935
Council	-163.9407	-163.3189	64.9383	64.7265
Quartz Creek	-165.0687	-163.5144	65.4551	64.9704

 

Data File Information

There are 13 data files with this data set in comma-separated (.csv) format. The files provide vegetation species as well as the percent ground cover occupied by the species, soil characterization, plot environmental data, biomass, NDVI, and leaf area index (LAI). All data were not collected at all plots and relevés.

Data not provided in the files are represented as -9999 or "not_provided" (also could represent not applicable).

Table 1. Data files

Data File Name	Description
atlas-1_environmental_data.csv	Environmental characterization data for ATLAS-1 research plots
atlas-1_lai.csv	Leaf Area Index (LAI) data collected from ATLAS-1 research grids
atlas-1_biomass.csv	Raw biomass data data collected from ATLAS-1 research grids
atlas-1_ndvi_lai_biomass_ivotuk.csv	NDVI, LAI, and biomass measurements at Ivotuk and provided for each of the four grids by vegetation type (MAT - moist acidic tundra (Ivotuk 1), MNT - moist nonacidic tundra (Ivotuk 3), ST - shrub tundra (Ivotuk 2), MT - mossy tussock tundra(Ivotuk 4))
atlas-1_spectral_ivotuk.csv	Spectral reflectance measurements at wavelengths from 340.8 to 1061.78 nm, ~1.4 nm resolution. Data were collected at Ivotuk and provided for each of the four grids by vegetation type (MAT - moist acidic tundra (Ivotuk 1), MNT - moist nonacidic tundra (Ivotuk 3), ST - shrub tundra (Ivotuk 2), MT - mossy tussock tundra(Ivotuk 4))
atlas-1_species_data.csv	Species cover data in comma separated (.csv) format. Both the author's determination and the current taxonomy according to the Panarctic Species List (PASL)
atlas-2_species.csv	Species cover data in comma separated (.csv) format. Both the author's determination and the current taxonomy according to the Panarctic Species List (PASL)
atlas-2_environmental_data.csv	Environmental characterization data for Council and Quartz Creek research plots
atlas-2_lai.csv	Leaf Area Index (LAI) data collected from the Council and Quartz Creek research grids
atlas-2_biomass.csv	Biomass measurements from Quartz Creek grids
atlas-2_soil_texture.csv	Soil texture data
atlas-2_soil_moisture.csv	Soil moisture data
atlas-2_soil_chemistry.csv	Soil chemistry data

 

ATLAS-1 Data files

The ATLAS-1 study plots were on the North Slope and include Barrow, Atqasuk, Oumalik, and Ivotuk.

 

 Table 2. Variables in the file atlas-1_environmental_data.csv

These data describe the environment of the plots and were collected during July 1998 and July 1999. Refer to the companion file atlas-1_envlegend.pdf for the ordinal scale descriptions and associated codes.

Column number	Variable	Units/format	Description
1	site		ATLAS study site
2	field_plot_number	numeric	Plot number as provided by the author
3	date	yyyymmdd	Date plot was investigated
4	latitude	decimal degrees	Plot latitude
5	longitude	decimal degrees	Plot longitude
6	elevation	m	Elevation in meters
7	surficial_geology	scalar	Surficial geology
8	surficial_geomorphology	scalar	Surficial geomorphology
9	topographic_position	scalar	Topographic position
10	slope	degrees	Slope of plot
11	aspect	degrees	Aspect
12	releve_shape		Relevé shape
13	releve_area	m2	Relevé area
14	organic_ layer_ depth	cm	Depth of the soil organic layer
15	soil_ph		Soil pH
16	soil_texture	%	Soil texture
17	plant_community_name	%	Percent of trees in the plant community
18	cover_low_shrubs	%	Percent of low shrubs in the plant community
19	cover_dwarf_shrubs	%	Percent of dwarf shrubs in the plant community
20	cover_prostrate_ dwarf_ shrub	%	Percent of prostrate dwarf shrubs in the plant community
21	cover_evergreen_shrubs	%	Percent of evergreen shrubs in the plant community
22	cover_deciduous_shrubs	%	Percent of deciduous shrubs in the plant community
23	cover_forbs	%	Percent of forbs in the plant community
25	cover_graminoids	%	Percent of graminoids in the plant community
26	cover_lichens	%	Percent of plot that was lichen
27	cover_bryophytes	%	Percent of plot that was bryophytes
28	cover_horsetails	%	Percent of plot that was horsetails
29	cover_rocks	%	Percent of plot that was bare rock
30	cover_bare_soil	%	Percent of plot that was bare soil
31	cover_water	%	Percent of plot that had water
32	cover_frost_scars	%	Percent of plot that had frost scars
33	total_dead	%	Percent of plot that had dead vegetation
34	canopy_ht	cm	Mean canopy height
35	remarks		comments

 

Table 3. Variables in the file atlas-1_biomass.csv

Raw biomass data collected June 27-July 18, 1999.

Column Number	Variable	Units/format	Description
1	site		Site name
2	vegetation_type		Vegetation type=MNT, Moist NonAcidic Tundra, or MAT, Moist Acidic Tundra
3	grid_plot_number		Grid plot number
4	moss	g/m2	Moss biomass
5	lichen	g/m2	Lichen biomass
6	equisetum	g/m2	Equisetum biomass
7	forb	g/m2	Forb biomass
8	deciduous_shrub_stem	g/m2	Deciduous shrub stem biomass
9	live_deciduous_leaf	g/m2	Live deciduous leaf biomass
10	dead_deciduous_leaf	g/m2	Dead deciduous leaf biomass
11	evergreen_shrub_stem	g/m2	Evergreen shrub stem biomass
12	live_evergreen_leaf	g/m2	Live evergreen leaf biomass
13	dead_evergreen_leaf	g/m2	Dead evergreen leaf biomass
14	live_graminoid	g/m2	Live graminoid biomass
15	dead_graminoid	g/m2	Dead graminoid biomass
16	deciduous_reproduction	g/m2	Biomass from deciduous reproduction
17	evergreen_reproduction	g/m2	Biomass from evergreen reproduction
18	total	g/m2	Total biomass
19	litter	g/m2	Total biomass from litter
20	total_evergreen_shrub	g/m2	Total biomass from evergreen shrub
21	total_deciduous_shrub	g/m2	Total biomass from deciduous shrub
22	total_graminoid	g/m2	Total biomass from graminoids
23	total_vascular	g/m2	Total biomass from vascular plants
25	total_shrub	g/m2	Total biomass from shrubs

 

Table 4. Variables in the data file atlas-1_lai.csv

These are LAI data for Atqasuk, Barrow and Oumalik grids collected between July 5-17, 1999 using a LICOR-2000 Plant Canopy Analyzer.

Column number	Variable	Units/format	Description
1	date	yyyymmdd	Date of LAI measurements
2	grid		Research grid where measurements were made
3	grid_point		Research grid point where measurements were made
4	lai		LAI

 

Table 5. Variables in the file atlas-1_ndvi_lai_biomass_ivotuk.csv

The data are for each gridpoint at each of the four grids at Ivotuk. The first four rows in the data file represent the grid (Ivotuk 1-4), grid point, vegetation type at the grid, and sampling period through columns 1-column 228. The biomass, NDVI, and LAI data are in column 1 below the grid information.

Variables and grid-column #1	Units/format	Description
grid_name		Grid name: Ivotuk_1, 2, 3 ,and 4; columns 2-28
grid_point		Grid points; columns 2-28
vegetation_type		Vegetation type at the grid: Ivotuk 1=MAT - moist acidic tundra;  Ivotuk 2=ST - shrub tundra, Ivotuk 3= MNT - moist nonacidic tundra, Ivotuk 4= MT - mossy tussock tundra. Columns 2-28
sampling_period		There were six sampling periods at each of the four grids covering June, July, and August, 1999. Columns 2-28
graminoid_alive	g/m2	Live graminoid biomass
graminoid_dead	g/m2	Dead graminoid biomass
graminoid_total	g/m2	Total graminoid biomass
moss	g/m2	Moss biomass
lichen	g/m2	Lichen biomass
horsetails	g/m2	Horsetails biomass
forb	g/m2	Forb biomass
deciduous_shrub_woody	g/m2	Deciduous shrub woody biomass
deciduous_shrub_live_foliar	g/m2	Deciduous shrub live biomass
deciduous_shrub_dead_foliar	g/m2	Deciduous shrub dead biomass
evergreen_shrub_woody	g/m2	Evergreen shrub woody biomass
evergreen_shrub_live foliar	g/m2	Evergreen shrub live foliar biomass
evergreen_shrub_dead_foliar	g/m2	Evergreen shrub dead foliar biomass
shrub_total	g/m2	Total shrub biomass
shrub_total_live	g/m2	Total live shrub biomass
shrub_total_live_foliar	g/m2	Total live shrub foliar biomass
shrub_total_dead	g/m2	Total dead shrub biomass
live	g/m2	Total live biomass
dead	g/m2	Total dead biomass
grand	g/m2	Grand total biomass
NIR (725-1060)		Near infrared
red (580-680)		Red
NIR-Red		Near infrared-red
NIR + Red		Near infrared+red
NDVI (NIR-R/NIR+R)		Calculated NDVI
LAI		LAI

Example data:

grid_name	IVOTUK 1	IVOTUK 1	IVOTUK 1
grid_point	J2	H5	I8
vegetation_type	MAT	MAT	MAT
sampling_period	1	1	1
graminoid_alive	1.79	0.29	0.05
graminoid_dead	6.03	2.17	0.82
graminoid_total	7.82	2.46	0.87
moss	7.03	2.11	21.85
lichen	0.165	8.87	2.78
horsetails	0	0	0
forb	0.005	0	0

 

Table 6. Variables in the file atlas-1_spectral_ivotuk.csv

The spectral reflectance data are for each gridpoint at each of the four grids at Ivotuk. The first four rows in the data file represent the grid (Ivotuk 1-4), grid point, vegetation type at the grid, and sampling period through columns 1-column 228. Measurements were made with a FieldSpec Pro spectroradiometer. Column 1 provides the wavelengths from 340.8 to 1061.78 nm at ~1.4 nm resolution for the respective row values.

Variable	Description
IVOTUK (1-4)	Study site Ivotuk
grid_name	Ivotuk grids 1-4
grid_point	Point on the grid where measurement was made
sampling_period	There were six sampling periods at each of the four grids covering June, July, and August, 1999
vegetation_type	Vegetation type at the grid: Ivotuk 1=MAT - moist acidic tundra;  Ivotuk 2=ST - shrub tundra, Ivotuk 3= MNT - moist nonacidic tundra, Ivotuk 4= MT - mossy tussock tundra
wavelength_nm	Wavelength in nanometers

Example data:

IVOTUK (1-4)
grid_name	IVOTUK 1	IVOTUK 1	IVOTUK 1	IVOTUK 2	IVOTUK 2	IVOTUK 2	IVOTUK 3	IVOTUK 3
grid_point	J2	H5	I8	D2	E7	D9	J6	G9
sampling_period	1	1	1	1	1	1	1	1
vegetation_type	MAT	MAT	MAT	ST	ST	ST	MNT	MNT
wavelength_nm

 

Table 7. Variables in the files atlas-1_species_data.csv and atlas-2_species_data.csv

These files contain species cover data for the ATLAS-1 and ATLAS-2 vegetation studies. Both the author's determination and the current taxonomy according to the Panarctic Species List (PASL) are listed. Taxa are listed in alphabetical order according to the accepted PASL name.

Column number	Column header	Description
1	PASL_taxon_scientific_name	Current nomenclature according to the Panarctic Species List (PASL)
2	PASL_taxon_scientific_name_author	Current nomenclature according to the Panarctic Species List (PASL) with the data authors name
3	dataset_taxon	Data set taxonomy
4-90	TURBOVEG_plot_accession_number and dataset_plot_number_author	Two rows of column headers which are plot numbers/accession numbers. The first row is TURBOVEG accession numbers. Column headers for ATLAS-1 data (TURBOVEG accession numbers): 11364-11378. Column headers for ATLAS-2 data (TURBOVEG accession numbers): 11379-11430. The 2nd row is dataset_plot_number_author, the plot numbers as named in the original data set. Species cover classes are the old Braun-Blanquet cover-abundance scale: r= (rare) + (common, but less than 1 percent) 1 (1-5%) 2 (6-24 %)  (6-25% for ATLAS-2 data) 3 (25-50%)  (26-50% for ATLAS-2 data) 4 (51-75%) 5 (76-100%)

ATLAS-1 data note: In three instances, taxa were lumped into a single taxon in the PASL: 1) Cladonia squamosa (Cladonia squamosa and Cladonia subsquamosa), 2) Dicranum spadiceum (Dicranum angustum and Dicranum spadiceum), 3) Polytrichastrum alpinum (Polytrichastrum alpinum and Polytrichastrum fragile).

ATLAS-2 data note: In two instances, taxa were lumped into a single taxon in the PASL: 1) Cladonia stellaris (Cladonia stellaris and Cladonia stellaris v. aberrans), and 2) Dicranum spadiceum (Dicranum angustum and Dicranum spadiceum). In the report, there was environmental data but no species data for a plot CC-C, and species data but no environmental or location data for plot C-F. Both of these plots were dropped due to lack of information.

 

ATLAS-2 data files

The author’s plots were numbered following a letter-number, and letter system, where the first letter equals the location of grid: C=Council, BH=Blueberry Hill, QC=Quartz Creek, CC=Cassiope Cone, or Lava, the number equals the plot number, and the letter(s), if present, A, B, C etc., equal the plot microsite.

 

Table 8. Variables in the file atlas-2_environmental_data.csv

These data describe the environment of the plots and were collected during July, 2000. Refer to the companion file atlas-2_envlegend_metadata.pdf for the code and scalar value definitions

Column number	Variable	Units/format	Description
1	releve		Relevé as provided by the author in form of a letter and number combination
2	turboveg_ num		TURBOVEG accession number
3	date	yyyymmdd	Date plot was investigated
4	latitude	decimal degrees	Plot latitude
5	longitude	decimal degrees	Plot longitude
6	plot_size	mxm	Size of plot in meters x meters
7	slope	degrees	Slope of plot
8	aspect	degrees	Direction-south, east, north, or west
9	elevation	m	Elevation
10	surficial_geology	scalar	Surficial geology
11	surficial_geomorphology	scalar	Surficial geomorphology
12	glacial_ geology	code	Glacial geology of the plot area
13	topographic_position	code	Topographic position
14	surface_stability	code	Surface stability with regard to avalanches, surface movements due to floods, etc. noted using an ordinal scale
15	site_moisture	scalar	Site moisture
16	organic_layer_depth	cm	Depth of the soil organic layer
17   to  27	thaw_depth_1 to thaw_depth_11	cm	Thaw depth measurements
28	thaw_depth	cm	Mean thaw depth
29	thaw_depth_std_deviation		Mean thaw depth, standard deviation
30	soil_units	code
31	soil_ph		Soil pH
32	soil_texture		Soil texture
33	exposure	scalar	Estimated exposure to winds
34	duration_snow	scalar	Estimated snow duration recorded using an ordinal scale
35	site_disturbance	scalar	Site disturbance by animals and humans. Comments provided
36	microsites	code	Microsites and description if present
37	plant_community_name		Names of plant communities
38	cover_trees	%	Percent of trees in the plant community
39	cover_tall_shrubs	%	Percent of tall shrubs in the plant community
40	cover_low_shrubs	%	Percent of low shrubs in the plant community
41	cover_dwarf_shrubs	%	Percent of dwarf shrubs in the plant community
42	cover_evergreen_shrubs	%	Percent of evergreen shrubs in the plant community
43	cover_deciduous_shrubs	%	Percent of deciduous shrubs in the plant community
44	cover_forbs	%	Percent of forbs in the plant community
45	cover_graminoids	%	Percent of graminoids in the plant community
46	cover_lichens	%	Percent of plot that was lichen
47	cover_bryophytes	%	Percent of plot that was bryophytes
48	cover_rocks	%	Percent of plot that was bare rock
49	cover_prostrate_ dwarf_ shrub	%	Percent of plot that was prostrate dwarf shrub
50	cover_bare_soil	%	Percent of plot that was bare soil
51	cover_water	%	Percent of plot that had water
52	cover_frost_scars	%	Percent of plot that had frost scars
53	total_dead	%	Percent of plot that had dead vegetation
54	canopy_ht	cm	Mean canopy height
55	comments		Comments
56	field_observer		Field observer name
57	site_location		Location of the site
58	additional_description		Additional description of location

 

Table 9. Variables in the file atlas-2_lai.csv

LAI measurements made at Quartz Creek on July 28 and 29, 2000.

Column number	Variable	Units/format	Description
1	grid		Sampling grid
2	date	yyyymmdd	Date of LAI measurement
3	lai		LAI
4	mean		Mean LAI
5	std_error		Standard error of the LAI measurements (+ or -)

 

Table 10. Variables in the file atlas-2_biomass.csv

Biomass measurements made at Quartz Creek on July 28 and 29, 2000.

Column number	Variable	Units/format	Description
1	grid		Sampling grid
2	location		Location on the grid. In addition, the mean and standard error are listed after the locations
3	moss	g/m2	Moss
4	lichen	g/m2	Lichen
5	forb	g/m2	Forb
6	horsetail	g/m2	Horsetail
7	Graminoid_live	g/m2	Live graminoid
8	Graminoid_dead	g/m2	Dead graminoid
9	shrub_foliage_live	g/m2	Live shrub foliage
10	shrub_foliage_dead	g/m2	Dead shrub foliage
11	shrub_stem_live	g/m2	Live shrub stem
12	shrub_stem_dead	g/m2	Dead shrub stem
13	litter	g/m2	Litter
14	Total_no_litter	g/m2	Total (without litter)

 

Table 11. Variables in the file atlas-2_soil_texture.csv

Soil samples were collected in July, 2000. Refer to the companion file atlas-2_soilslegend.pdf for code definitions.

Column number	Variable	Units/format	Description
1	releve		Relevé at the plot
2	date	yyyymmdd	Date soil was sampled
3	classification		Soil texture classification
4	depth	cm	Soil depth
5	horizon		Soil horizon
6	color	Munsell color	Soil color
7	structure_grade	code	Soil structure grade
8	structure_classification	code	Soil size classification
9	structure_type	code	Soil structure type
10	gravel	percent	Percent of gravel in the soil
11	consistency	code	Soil consistency
12	texture	code	Soil texture
13	boundaries_distinct	code	Distinct boundaries
14	boundaries_topography	code	Topography
15	collected	y/n	Sample collected
16	notes		Notes

 

Table 12. Variables in the file atlas-2_soil_moisture.csv

Soil samples were collected in July, 2000. Refer to the companion file atlas-2_soilslegend.pdf for code definitions.

Column number	Variable	Units/format	Description
1	releve		Relevé where sample was taken
2	sample_num		Sample number
3	horizon		Soil horizon
4	wet_wt	gm	Soil wet weight
5	dry_wt_tare	gm
6	tare_wt	gm
7	dry_wt	gm	Soil dry weight
8	water_wt	gm	Water weight of soil
9	moisture	%	Soil moisture

 

Table 13. Variables in the file atlas-2_soil_chemistry.csv

Soil data samples were collected in July, 2000 .Refer to the companion file atlas-2_soilslegend.pdf for code definitions.

Column number	Variable	Units/format	Description
1	releve		Relevé where sample was taken
2	horizon		Soil horizon
3	ph		Soil pH
4	p	ppm	Soil phosphorus
5	k	ppm	Soil potassium
6	ca	ppm	Soil calcium
7	mg	ppm	Soil magnesium
8	na	ppm	Soil sodium
9	c	%	Soil carbon
10	n	%	Soil nitrogen
11	loss_on_ignition	%
12	sand	%	Soil sand content
13	silt	%	Soil silt content
14	clay	%	Soil clay content

 

 

Companion Files

Table 14. Companion files with this data set.

Companion files	Description
atlas_walker_permafrost_periglac_thawdepth.pdf	Report which provides additional information regarding the ATLAS-1 data collection methods, particularly for thaw depth
atlas-1_edwards_westrnalaska_grids.pdf	Provides information on the ATLAS-1 study including accuracy assessments and code information for scalar data
atlas-1_envlegend.pdf	Provides the codes and scalar definitions used in the ATLAS-1 data files
atlas-1_riedel_ndvi_lai.pdf	Report which provides additional information regarding the ATLAS-1 NDVI, LAI, and biomass measurement methods
atlas-1_plotphotos.pdf	Provides photos of the ATLAS-1 plots
atlas-2_raynolds_2002_datareport.pdf	Provides additional information on the data collection methods and data tables for the ATLAS-2 project
atlas-2_soilslegend.pdf	Provides the codes and scalar definitions used in the ATLAS-2 soil data files
atlas-2_envlegend.pdf	Provides the codes and scalar definitions used in the ATLAS-2 environmental data files
atlas-2_photos.pdf	Provides photos of the plots at the ATLAS-2 sites
ATLAS_veg_plots.pdf	A pdf of this guide document

These data could be useful to climate change studies and land use environmental studies.

Refer to the companion files listed in the Section 2 of this document.

Site description

This data set provides environmental, soil, and vegetation data collected as part of the Arctic Transition in Land-Atmosphere System (ATLAS) project, ATLAS-1 and ATLAS-2.  The ATLAS-1 study plots were on the North Slope and include Barrow, Atqasuk, Oumalik, and Ivotuk. ATLAS-2 sites included Council and Quartz Creek on the Seward Peninsula.

Grids were subjectively established at all sites.  Some of the grids were in homogeneous stands of vegetation that were considered representative of the regional climate or zonal vegetation. Other grids were in stands of vegetation that were regionally extensive.

The source species and environmental data for the plots were obtained from homogeneous areas of dominant vegetation within the grids. In some cases where the vegetation was more heterogeneous, as for example in patterned ground, areas with frost boils, stone stripes, or closely spaced water tracks, samples were divided into representative microhabitats with each relevé representing a microsite within the grid. These microsites were labeled with the letters A, B, C as needed (Edwards et al., 2000).

 

Methods-ATLAS-1

The grids at Atqasuk (A-1 (1 grid)), Barrow (B-1 (1 grid)), Ivotuk (I-1, I-2, I-3, I-4 (4 grids)) were 100 x 100-m; grids at Oumalik (O-1 and O-2 (2 grids)) were 50 m x 50-m.

Plot cover

Percent cover values for lifeforms were collected at all relevés. Complete plant species composition data were obtained, using the Braun-Blanquet method.

 

Vegetation

Vegetation from 15 relevé within eight different grids at Barrow, Atqasuk, Ivotuk and Oumalik were described. At Atqasuk (A-1 (1 grid)), Barrow (B-1 (1 grid)), and Ivotuk (I-1, I-2, I-3, I-4 (4 grids)), 100 x 100-m grids were established; 50 x 50-m grids (O-1 and O-2 (two grids)) were established at Oumalik. Subjectively located within the grids were one or more circular relevés (10-m in diameter, except for Oumalik, where they were 5-m in diameter).

The 15 relevés represent microsites within the grids related to, for example patterned ground features. These microsites were labeled with the letters A, B, C as needed. Plots occur in 14 plant communities within five broad habitat types including: a) willow shrub vegetation of riparian areas and warm habitats (south-facing slopes) (one plot), b) sedge grass and dwarf shrub mire and fen vegetation (two plots), c) bog vegetation, acidic mires, including tussock tundra (six plots), d) frost boil vegetation in nonacidic tundra (one plot), and e) dry and mesic dwarf-shrub and graminoid vegetation on non-acidic substrate (five plots).

All of the data are for the SW corners of the grids except for O-1A and O-1B, where they came from the center of the grids, and Atqasuk where the location for the point was not given.

 

Leaf Area Index: Atqasuk, Barrow and Oumalik

LAI  at the Atqasuk, Barrow and Oumalik grids were collected between July 5-17, 1999, using a LICOR-2000 Plant Canopy Analyzer. An above-canopy reading (control) was followed by four below-canopy readings (which were taken above the moss layer) at 33 random points within each grid. At each point, the four below-canopy measurements were taken along the axes of the grid at 1-meter from the grid point. All measurements were taken facing away from the sun and an umbrella was used to shade the sensor on sunny days. LAI was calculated for each point (Edwards et al., 2000).

 

NDVI, LAI, and biomass at Ivotuk

In 1999 spectral and biomass data were collected from each of the four grids at Ivotuk, each grid representative of a different vegetation type during  the 1999 growing season. Each grid was 100 x 100-m, with each grid point represented by a letter (A-K) and number (1-11) combination. Sampling periods were 1 - June 6-11; 2 - June 18-25; 3 - July 2-10; 4 - July 15-26; 5 - July 29 to August 6; 6 - August 13-20; 7 - August 22-26.

• Spectral reflectance data (range 340-1060 nm, ~1.4 nm resolution) were collected using an Analytical Spectral Devices, FieldSpec Pro. Measurements were taken at 20 random points within each grid; the same 20 points were used throughout the growing season. Data were collected preferentially during clear sky conditions and close to midday (10AM-3PM). The fiber-optic sensor with a 25 degree field-of-view was held at nadir above each relevé at 1-m height, yielding a circular footprint of about 0.35 m2. Each measurement is the average of five samples taken at 1-second intervals. White reference calibrations were made prior to each measurement using a Spectralon plate, as well as a dark reference (Riedel et al., 2005).
• LAI was measured using a LI-COR LAI-2000 Plant Canopy Analyzer. Above- and below-canopy radiation measurements were made with a ‘fish eye’ optical sensor with a five-ring 148 degree angle-of-view. Below-canopy measurements were made just above the moss layer. LAI was calculated using a model of radiative transfer in vegetation canopies and then stored in the unit data logger. At each of the 20 grid points, one above-canopy reading was taken, and four below-canopy readings were taken (1-m north, east, south and west of the grid point) to yield a single LAI value.

Above-ground phytomass was collected from 10 randomly selected 20-cm x 50-cm plots within each grid. Phytomass sampling occurred near, but not within, the footprints of LAI and NDVI measurements. On the fourth sample period (15–26 July), the number of phytomass plots harvested was doubled for MAT and MT. On the fifth sample period (27 July to 7 August), the number of phytomass plots harvested was doubled for MNT and ST. Vascular plants were clipped at the top of the moss surface; mosses were clipped at the base of the green layer. Phytomass samples were sorted into six main categories (horsetails, other forbs, graminoids, lichens, mosses, and shrubs). The graminoid and shrub samples were sorted further into subcategories. Graminoid phytomass was divided into live and dead material. Shrub phytomass was divided into evergreen and deciduous, which were then separated into woody, foliar live, and foliar dead components. Dead material was combined into a single pool, referred to as standing dead (Riedel et al., 2005).

Figure 2. Ivotuk-4 grid. This grid has homogeneous acidic tussock tundra with abundant Sphagnum moss (photo from Edwards et al., 2000).

Biomass

One 20-cm x 50-cm quadrat of biomass was harvested for each grid point/date combination (except for Ivotuk 2 and 4). Vascular biomass was clipped at the top of the moss layer, and the moss was clipped at the bottom of the green layer. Biomass was sorted into the following vegetation types: algae, moss, lichen, horsetail, other forbs, graminoids, deciduous shrubs, and evergreen shrubs. Graminoids were further sorted into live and dead, and shrubs were further sorted into wood, foliar live, foliar dead. Biomass samples were dried and weighed (Edwards et al., 2000).

 

Methods-ATLAS-2

The grids at Council and Quartz Creek were 100 x 100-m. The author’s plots were numbered following a letter- number, and letter system, where the first letter equals the location of the grid.

• Council : C=Council, BH=Blueberry Hill, CC=Cassiope Cone
• Quartz Creek: QC=Quartz Creek or Lava,

The number equals the plot number, and the letter(s), if present, A, B, C etc., equals the plot microsite.

All data were collected 26 June to 29 July, 2000 unless otherwise noted.

 

Plot cover

Percent cover values for lifeforms were collected at all relevés. Complete plant species composition data were obtained, using the Braun-Blanquet method. Lichen and moss identifications were verified by scientists from the Komarov Botanical Institute.

 

Plot environmental data

A total of 52 relevés were collected from the grids and other sites. A variety of environmental site data were collected from each relevé including landforms, surficial geology, surficial geomorpholgy, microsites, site moisture, soil moisture, glacial geology, topographic position, soil unit, exposure to wind, estimated duration, animal and human disturbance, and stability.

 

Vegetation

Forty-five plots were assigned to five different arctic community types: a) tall forb and shrub vegetation on mesic-moist soil (13 plots); b) dwarf-shrub heath and low shrub vegetation on acidic poor substrate (13 plots); c) bog vegetation, acidic mires, including tussock tundra (eight plots); d) dry and mesic dwarf-shrub heath and graminoid vegetation on non-acidic tundra (nine plots); and e) lichen communities on silicate rocks (two plots). Of the remaining seven plots, six are undefined forest types (C1, C4-A, C-9, C-A, C-C, C-E) and plot C-F is not included due to insufficient community data.

Four grids were established at Quartz Creek and three at Council. The grids were established in zonal vegetation and other vegetation types that locally cover large areas. The data from the grids include vegetation type (or species in forests) and microsite at each of the 121 grid points, and height of the vegetation, thickness of the moss layer, thickness of the soil organic horizons, phytomass and leaf-area index from a subset of grid points.

Thirty-one vegetation plots were sampled from sites at Council, Quartz Creek, and along the roads between these locations. Some of these were in complexes of vegetation that contained up to three plant communities, so a total of 52 stands of vegetation (relevés) were sampled.

In most cases the relevés were approximately 10 x 10-m, though the size was increased in six heterogeneous areas, and conformed to microsite variations. All the grids contained at least one relevé. At each grid, vegetation heterogeneity was sampled at 121 gridpoints, spaced every 10 meters (A1-K11). In the Council forest grid (C1), and the shrub grid (C3) the point was described as either tree canopy, shrub canopy, or clearing; and the tree or shrub species at the point was noted. At the other grids, the vegetation type and the microsite type were noted at each point. The vegetation height was measured at 20 randomly chosen gridpoint. The depth of the live and dead nonvascular layer was measured, and the dominant species noted. The general height of the vascular vegetation was measured and the dominant species noted. The height of the microrelief was measured.

Figure 3. Seward Peninsula Lava site. Patches of vegetation occur on more weathered areas of the lava flow (photo from Raynolds et al., 2002).

 

Leaf Area Index

Leaf area index (LAI) was measured at each of the four grids at Quartz Creek at every 10 meters along a 100-m transect using a LICOR LAI-2000 Plant Canopy Analyzer. An above-canopy reading (control) was followed by four below-canopy readings, taken above the moss layer along the axes of the grid at 1 m from the point. All measurements were taken facing away from the sun, and a sun screen was used to shade the sensor on sunny days. These measurements were repeated at 33 random points within each grid. A 90 degree field-of-view shield was used to prevent interference from the observers. LAI was calculated for each point, and mean LAI for each grid was calculated. All measurements were made on July 28 and 29, 2000 (Raynolds et al., 2002).

 

Biomass

Clip harvests were collected for above ground biomass estimates at three Quartz Creek grids. At 10 random locations within in the grid, all above-ground biomass was clipped from a 20 x 50-cm area. In the shrub plot (QC3), the shrubs were sampled in a 1 x 1-m area, while the understory was sampled in a 20 x 50-cm area. The clip harvests were sorted by major plant functional type (moss, lichen, forb, horsetail, deciduous shrub, evergreen shrub, graminoid) in the field. All vascular plants were clipped at the top of the moss surface. Green stem bases below the moss surface were also included in the clip harvest. Mosses were clipped at the base of the green portion. The samples were frozen and returned to the UAF laboratory where they were further sorted into live and dead categories. Both shrub categories were divided into their foliar, reproductive, and stem components. Biomass samples were dried to constant weight at 50 degrees C, and the dry weights were then used to estimate total g/m2 for each grid and functional type with the grid (Raynolds et al., 2002).

 

Soil Description

Soil samples were collected at each grid. At the Council grids, random points were chosen along six rows. At the Quartz Creek grids, random points were chosen along each of the 11 rows (A-K). The organic horizons (Oi, Oe, and Oa ) were measured and described. Soils for analysis were collected in soil cans from the top of the B horizon. Samples were dried and weighed to calculate soil moisture. Chemical and size composition were analyzed at the Palmer Experimental Laboratory. Measurements were made from 2000-07-11 to 2000-07-29.

 

Thaw depth: ATLAS-1 and ATLAS-2 sites

Data from Barrow, Atqasuk, Oumalik, Ivotuk, Quartz Creek, and Council were collected in 1999. At Barrow, Atqasuk, and Quartz Creek data from the nearby CALM grids (Brown et al., 2000) were used.

The thaw depth was monitored using a blunt tipped steel probe that was inserted into the soil to the point of contact with hard frozen soil. Measurements were taken at 10 m intervals on the 100 x 100-m grids (121 measurements per grid), and at 0.5 m intervals on the 10-m grids (Walker et al., 2003). Thaw depth data can also be found in related datasets archived at the ORNL DAAC.  See the Overview section of this document.

Refer to the companion file atlas-2_raynolds_2002_datareport.pdf for additional information.

This data set was provided by the GINA repository at http://geobotanical.portal.gina.alaska.edu/catalogs/9781-alaska-arctic-vegetation-archive-atlas-1-atqa and http://geobotanical.portal.gina.alaska.edu/catalogs/10671-alaska-arctic-vegetation-archive-atlas-2-veget.

Brown, J., K.M. Hinkel, and F.E. Nelson. 2000. The circumpolar active layer monitoring (CALM) program: research designs and initial results. Polar Geography 24: 165–258. http://dx.doi.org/10.1080/10889370009377698

Edwards, E. J., A. Moody, and D. A. Walker. 2000. A western Alaskan transect to examine interactions of climate, substrate, vegetation, and spectral reflectance: ATLAS grids and transects, 1998-1999. ARCSSATLAS-Northern Ecosystem Analysis and Mapping Laboratory data report.Institute of Arctic Biology, University of Alaska Fairbanks, Fairbanks, Alaska, USA.

Raynolds, M.K., C.R. Martin, D.A. Walker, A. Moody, and C. Thayer-Snyder. 2002.Atlas Vegetation Studies Seward Peninsula, Alaska, 2000. Vegetation, Soil, and Site Information, with Seward Vegetation Map. ARCSS-ATLAS-AGC data report, Alaska Geobotany Center, University of Alaska Fairbanks, Fairbanks, Alaska USA.

Riedel, S.M., H.E. Epstein, D.A. Walker, D.L. Richardson, M.P. Calef, E. Edwards, and A. Moody. 2005. Spatial and temporal heterogeneity of vegetation properties among four tundra plant communities at Ivotuk, Alaska, U.S.A. Arctic, and Alpine Research.37:25-33. https://doi.org/10.1657/1523-0430(2005)037[0025:SATHOV]2.0.CO;2

Walker, D.A., G.J. Jia, H.E. Epstein, M.K. Raynolds, F.S. Chapin III, C. Copass, L.D. Hinzman, J.A. Knudson, H.A. Maier, G.J. Michaelson, F. Nelson, C.L. Ping, V.E. Romanovsky and N. Shiklomanov. 2003. Vegetation-soil-thaw-depth relationships along a low-arctic bioclimate gradient, Alaska: synthesis of information from the ATLAS studies. Permafrost and Periglacial Processes. 14:103-123. https://dx.doi.org/10.1002/ppp.452