biocrusthab English utf8 dataset McMurdo Dry Valleys LTER Information Manager im@mcmlter.org pointOfContact 2024-04-25 ISO 19115-2 Geographic Information - North American Profile Metadata - Data with Biological Extensions ISO 19115-2:2009(E) Biophysicochemical properties and hyperspectral reflectance values of biocrust and soil samples, Fryxell Basin, McMurdo Dry Valleys, Antarctica (2022) 2024-04-25 publication Sarah Power Virginia Tech http://www.vt.edu/ snpower@vt.edu pointOfContact Mark Salvatore Northern Arizona University https://nau.edu mark.salvatore@nau.edu http://msalvatore.net pointOfContact Byron Adams Brigham Young University byron_adams@byu.edu https://biology.byu.edu/adams-lab pointOfContact John "Jeb" Barrett Virginia Tech http://www.vt.edu/ jebarre@vt.edu https://www.biol.vt.edu/faculty/barrett/index.html pointOfContact documentDigital This data package includes biophysicochemical properties of biocrust and soil samples collected in-situ within the Lake Fryxell basin of the McMurdo Dry Valleys, Antarctica during December 2022 at 64 different terrestrial locations. These parameters include biological (ash-free dry mass, pigment concentration, soil invertebrate counts), physical (gravimetric water content, electrical conductivity, pH), and chemical (inorganic nitrogen, inorganic phosphorous, total nitrogen, soil organic carbon) properties of the surface soil, biocrust, and underlying soil. This package also contains reflectance measurements of individual grab samples of biocrust, soil, and rock collected from each of the field sites, acquired in a laboratory using a hyperspectral spectrometer. Additionally, this package contains parameters derived solely from geospatial data for each of the field sites, including aspect, slope, elevation, gravimetric water content, and snow frequency. These data were used to model habitat suitability of biocrusts in the Fryxell Basin using both in-situ field survey data and geospatial parameters. They aid in our understanding of the ecology of biocrust communities, where they are located throughout the Fryxell basin, and the structure and functioning of these microhabitats as well as improving understanding of the regional carbon budget. These data also highlight the importance of snow patch-associated biocrust communities, which are understudied but likely an important piece of the overall carbon budget in this region.  Name: Meredith Snyder Role: field crew Name: Jesse Jorna Role: field crew Name: Abigail Borgmeier Role: field crew Name: Barbara R. Niederlehner Role: lab technician Name: Renée F. Brown Role: data manager completed McMurdo Dry Valleys LTER Information Manager im@mcmlter.org pointOfContact inorganic nutrients organic matter population dynamics primary production theme LTER Core Areas English This is the Taylor Valley, a subjectively approximated contour by San Gil. We use this to denote the geographical extent of studies that encompass the whole Taylor Valley. According to Wiki contributors, the Taylor Valley is the southernmost of the three large Dry Valleys in the Transantarctic Mountains, Victoria Land, located west of McMurdo Sound. The valley extends from Taylor Glacier in the west to McMurdo Sound at Explorers Cove at the northwest head of New Harbour in the east and is about 29 kilometres (18 mi) long. It was once occupied by the receding Taylor Glacier, from which it derives its name. Taylor Valley contains Lake Bonney in the west (inward), and Lake Fryxell in the east (coastward), and Lake Hoare, Lake Chad, Mummy Pond and Parera Pond close together between the two. Further east of Lake Bonney is Pearse Valley. Taylor Valley is separated from Wright Valley in the north by Asgard Range, and from Ferrar Glacier in the south by Kukri Hills. 163.624877929690 161.707763671880 -77.808487073526 -77.519802097166 ground condition 2022-12-20 2022-12-25 Funding for this work was provided by the National Science Foundation (NSF) grants #OPP-1637708 and #OPP-2224760 to the MCM LTER. https://mcm.lternet.edu/sites/default/files/data/mcmlter-soils-power-biocrusthab_biol-20240501_0.csv biological eng; US McMurdo Dry Valleys LTER biological Number of Header Lines : 1 Orientation : Column Quote Character : "Field Delimiter : , false dataset_code Internal dataset code. site_id Site identifier. Refer to the "site" dataset within this package for additional metadata. afdm Ash-free dry mass (AFDM) content of the sample. chla Chlorophyll-a (Chl-a) concentration of the sample. caro Carotenoid concentration of the sample. scyto Scytonemin concentration of the sample. DBF https://mcm.lternet.edu/sites/default/files/data/mcmlter-soils-power-biocrusthab_biol-20240501_0.csv https://mcm.lternet.edu/sites/default/files/data/mcmlter-soils-power-biocrusthab_biota-20240501.csv biota eng; US McMurdo Dry Valleys LTER biota Number of Header Lines : 1 Orientation : Column Quote Character : "Field Delimiter : , false dataset_code Internal dataset code. site_id Site identifier. Refer to the "site" dataset within this package for additional metadata. phylum Phylum-level taxonomic classification. genus Genus-level taxonomic classification. Blank cells indicate samples not classified to the genus level. life_stage Life stage, either adult or juvenile, of counts in phylum Nematoda. sex Sex, either male or female, of adult life stage counts in phylum Nematoda, except for Plectus spp., which are all female. vital_status Vital status, either live or dead, of counts in phylum Nematoda. gwc_pct Gravimetric water content of the soil sample. raw_count Raw counts of invertebrates extracted from ~100 g of soil. transformed_count Transformed counts of invertebrates, expressed in number of organisms per 1 kg dry weight equivalent soil. remarks Remarks about the sample. DBF https://mcm.lternet.edu/sites/default/files/data/mcmlter-soils-power-biocrusthab_biota-20240501.csv https://mcm.lternet.edu/sites/default/files/data/mcmlter-soils-power-biocrusthab_hspectral-20240501.csv hyperspectral eng; US McMurdo Dry Valleys LTER hyperspectral Number of Header Lines : 1 Orientation : Column Quote Character : "Field Delimiter : , false dataset_code Internal dataset code. site_id Site identifier. Refer to the "site" dataset within this package for additional metadata. moisture_level Moisture status at the time the spectra were acquired. DRY: sample was dry. DAMP: moisture representative of field conditions when sampled; i.e. “field moist”. WET: moisture added; sprayed twice with spray bottle of distilled water. sample_type Type of sample. SOIL: soil, likely including cobbles. BIO: biocrust present, dense, or incipient. ROCK: larger rock representative of nearby area (only sampled when surface area appeared dominated by specific/unique rock type). band_um Wavelength band of reflectance at 0.001 um increments. reflectance Reflectance values (unitless) associated with each band and measurement. remarks Remarks about the rock type, if applicable. DBF https://mcm.lternet.edu/sites/default/files/data/mcmlter-soils-power-biocrusthab_hspectral-20240501.csv https://mcm.lternet.edu/sites/default/files/data/mcmlter-soils-power-biocrusthab_physchem-20240501_0.csv physchem eng; US McMurdo Dry Valleys LTER physchem Number of Header Lines : 1 Orientation : Column Quote Character : "Field Delimiter : , false dataset_code Internal dataset code. site_id Site identifier. Refer to the "site" dataset within this package for additional metadata. gwc Gravimetric water content (GWC) of the sample, expressed in grams of water per gram of dry soil. ec Electrical conductivity (EC) of the sample. ph pH of the sample. nh4 Inorganic nitrogen concentration of the sample in the form of ammonium (NH4+), expressed in micrograms of N per gram of dry soil. no3 Inorganic nitrogen concentration of the sample in the form of nitrate (NO3-), expressed in micrograms of N per gram of dry soil. po4 Inorganic phosphorus concentration of the sample in the form of phosphate (PO43-), expressed in micrograms of P per gram of dry soil. soc Soil organic carbon concentration of the sample, expressed in milligrams of C per gram of dry soil. tn Total nitrogen concentration of the sample, expressed in milligrams of N per gram of dry soil. DBF https://mcm.lternet.edu/sites/default/files/data/mcmlter-soils-power-biocrusthab_physchem-20240501_0.csv https://mcm.lternet.edu/sites/default/files/data/mcmlter-soils-power-biocrusthab_site-20240501_0.csv site eng; US McMurdo Dry Valleys LTER site Number of Header Lines : 1 Orientation : Column Quote Character : "Field Delimiter : , false dataset_code Internal dataset code. site_id Site identifier. latitude Latitude of site in decimal degrees. longitude Longitude site in decimal degrees. aspect Aspect of site from DEM in degrees. slope Slope of site from DEM in degrees. elevation Elevation of site from DEM in meters. biocrust Whether biocrust is absent, incipiently present (incipient), or present. mean_gwc Mean percentage gravimetric water content, determined using remote sensing techniques (see methods). snow_frequency Percentage of time area is covered by snow, determined using remote sensing techniques (see methods). DBF https://mcm.lternet.edu/sites/default/files/data/mcmlter-soils-power-biocrusthab_site-20240501_0.csv dataset In-situ Environmental Sampling & Analyses At 64 locations throughout the Fryxell basin, we documented whether biocrust was present. At each site, surface layer samples of soil or biocrust (if present) of known area were collected for pigment analysis, organic matter content, and hyperspectral reflectance analysis later in the laboratory. We also collected underlying soil down to 10 cm below the surface for gravimetric water content (GWC), electrical conductivity (EC), pH, inorganic nitrogen (N) concentration in the form of ammonium (NH4+) and nitrate (NO3-), inorganic phosphorus (P) concentration in the form of phosphate (PO4-3), soil organic carbon (SOC), total nitrogen (TN), and invertebrate abundance (nematodes, tardigrades, and rotifers). Ash-free dry mass (AFDM). The surface layer soil and biocrust samples were measured for AFDM by weighing a known area of sample, oven drying, weighing, then combusting at 550 °C for 24 hr using a muffle furnace, gently stirring samples halfway through combustion, and reweighing after cooling in a desiccator. The rehydration of clays was assumed negligible, so we did not rewet samples. Pigments. We estimated pigment concentration on the surface ~1 cm layer soil and biocrust samples using a trichromatic spectrophotometric method for chlorophyll-a, carotenoids, and scytonemin at 663, 490, and 384 nm, respectively (Garcia‐Pichel and Castenholz, 1991). Samples were not exposed to direct light throughout the entire process. The samples were dried at 105 °C for 24 hr, sieved through a 4 mm sieve, and extracted for 24 hr at ambient temperature in 90% unbuffered acetone using a 3.75:10 soil to solvent ratio for samples which contained none or minimal biocrust and a 0.5:10 biocrust to solvent ratio for samples containing dense biocrust, based on protocols from Couradeau et al. (2016) and the McMurdo Dry Valleys Long Term Ecological Research Program (MCM LTER) standard methods. After centrifugation, the extracts were analyzed on a spectrophotometer using 10 mL cuvettes. The absorbances contributed by each pigment were calculated using the trichromatic equations outlined in Garcia‐Pichel and Castenholz (1991), and the pigment concentrations were calculated using the Beer-Lambert Law with the extinction coefficients of 89.7 L g-1 cm-1 for chlorophyll-a (Couradeau et al., 2016), 112.6 L g-1 cm-1 for scytonemin (Brenowitz and Castenholz, 1997), and 262 L g-1 cm-1 for carotenoids (Thrane et al., 2015). Invertebrate counts. The number of soil organisms (nematodes, rotifers and tardigrades), divided by species, sex and maturity was determined at each of the 64 sites. Invertebrate abundance was enumerated using inverted light microscopy on soil solutions using a modified sugar-centrifugation extraction procedure described by Freckman and Virginia (1993). Gravimetric water content (GWC). Water content was determined as the mass of water per mass of dry soil. This was conducted by weighing field moist soil, drying in an oven at 105 °C for 24 hr, and reweighing the soil after. Electrical conductivity (EC). We measured electrical conductivity using a 1:5 soil to DI H2O slurry using a benchtop conductivity probe. pH. We measured pH using a 1:2 soil to DI H2O slurry using a benchtop pH probe. Inorganic N and P. We extracted inorganic N (NH4+ and NO3-) in 2 M potassium chloride and inorganic P (PO4-3) in 0.5 M sodium bicarbonate. Inorganic N and P were measured on extracts using a Lachat flow injection analyzer. Total N and Soil Organic C (SOC). We measured SOC and TN using an Elementar Vario MAX Cube analyzer after fumigating samples with concentrated hydrochloric acid to remove the influence of carbonates on SOC values. Remote Sensing Analyses Geospatial Parameters. Parameters based solely on geospatial data were extracted for each of the 64 sites as well. These include aspect, slope, elevation, GWC, and snow frequency. Aspect, slope, and elevation were extracted from a high-resolution DEM (Fountain et al. 2017), the rasterized GWC layer was developed for this region by Salvatore et al. (2023) using 21 WorldView-2 and -3 images, and the rasterized snow frequency layer was also developed for this region using albedo thresholds with multiple images over the course of the austral summer (see also, Thapa-Magar et al. in review). Snow frequency was calculated as the percentage of time (the proportion of the total images captured during the austral summer) that each pixel was identified as being snow covered (e.g., 0% representing no snow observed in any of the imagery and 100% representing snow cover in all summer images analyzed). Hyperspectral reflectance of field samples. Spectra were acquired of samples from each of the 64 sites using an Analytical Spectral Devices (ASD) FieldSpec4 high-resolution hyperspectral reflectance spectrometer set up for use in a stable lab environment. Data were collected between 0.35 µm and 2.5 µm at a 0.001 µm sampling interval. A halogen lamp was used to illuminate the samples at 30° off-nadir, while reflectance was measured at nadir using the ASD’s bare fiber optic cable roughly 3 cm above the sample surface. Spectra were collected of the samples in moisture conditions ranging from dry, damp (field-moist: moisture conditions present at time of sample collection), to wet which were sprayed twice with an aerosolizing spray bottle with distilled water. The samples were placed under the halogen illuminating lamp and let sit for 60 seconds before a spectrum was acquired. This was performed identically for each sample to ensure consistency. To minimize instrument noise, particularly at the longest and shortest wavelengths where the output of the halogen bulb is lowest, we averaged 50 individual spectra for each sample. Metadata Access Constraints: none Metadata Use Constraints: none annually McMurdo Dry Valleys LTER http://mcmlter.org/ pointOfContact