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This dataset contains photosynthetic light response data from biological soil crusts collected from a gypsum sand sheet at White Sands National Park, NM, USA in three different seasons. This study aims to 1) assess the carbon fixation capacity of biocrust types; 2) assess biocrust carbon fixation response under varying incubation times; 3) and understand variability in carbon fixation response in different seasons. Sample collection occurred in July 2020 (summer), September 2021 (fall), and March 2022 (winter). The biocrust types of interest were light cyanobacterial, dark cyanobacterial, Peltula lichen, Clavascidium lichen, and moss crusts. Samples were collected with the intention of taking carbon fixation measurements after different incubation periods (30 min, 2 hr, 6 hr, 12hr, or 24 hr in 2020, and 30 min, 2 hr, 6 hr, 12hr, 24 hr, or 36 hr in 2021 and 2022). For each condition (biocrust type and incubation time) there were five replicates in 2020 (total n=125) and ten replicates in 2021 and 2022 (total n=300). After collection, the intact samples were re-wetted and subjected to their respective incubation period and measured for photosynthetic response. The resulting light response curves and photosynthetic information was be used for comparing biocrust type, incubation time response differences, and seasonal variation to understand variability of biocrust carbon flux response at a single site. This data set includes the light response curve values and photosynthetic data calculated from these curves and raw LICOR output files compiled into 3 spreadsheet files. The included 2020 data is also associated with the White Sands National Park data from Jornada Study 549. This dataset accompanies the in-press article by Hoellrich et al. (2023) cited below, and the study is now complete. Hoellrich, Mikaela R., Darren K. James, David Bustos, Anthony Darrouzet-Nardi, Louis S. Santiago, and Nicole Pietrasiak. "Biocrust carbon exchange varies with crust type and time on Chihuahuan Desert gypsum soils." Frontiers in Microbiology 14:1128631.
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Data from nitrogen isotopic analyses used to calculate biological nitrogen fixation (BNF) rates and field measurements from lichen, bryophyte, litter, and soil samples in MAT2006 plots, Arctic LTER, Toolik Field Station, Alaska, summers 2022-2023.
This dataset contains nitrogen (N) fixation and isotope data from experimental samples collected at Toolik Lake, Alaska during the 2022 and 2023 growing seasons. Sampling was conducted across multiple block treatments to capture spatial variability and included four substrate types: lichen, moss, litter, and soil. Within each plot, substrates were collected systematically along transects to ensure representative sampling, with lichen samples collected opportunistically due to lower abundance. Samples were incubated in the field under ambient conditions using 15N₂ to measure biological nitrogen fixation (BNF). In 2023, a short-term wetting experiment was conducted to assess the influence of moisture on BNF rates, with subsamples exposed to controlled additions of water. Across both years, data include isotope ratios, incubation conditions, moisture, fresh and dry biomass, and treatment assignments. The dataset provides information on BNF across substrate types, moisture regimes, and fertilization treatments in Arctic tundra. These data support investigation of N cycling processes, the influence of moisture and fertilization on fixation rates, and variability across vegetation types. The dataset is complete for the two field seasons (2022 and 2023) and includes sample- and block-level metadata necessary for reuse in ecological and biogeochemical research.
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- Award ID(s):
- 2224743
- PAR ID:
- 10674819
- Publisher / Repository:
- Environmental Data Initiative
- Date Published:
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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