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{"Abstract":["This study investigated the question, "Does climate change\n affect vegetation and seed bank composition in desert\n grasslands?" The work was done in the Sevilleta National\n Wildlife Refuge, New Mexico, USA, in in the Extreme Drought in\n Grassland Experiment (EDGE). Vegetation and seed bank species\n composition were recorded in black grama (Bouteloua eriopoda) and\n blue grama (B. gracilis) grasslands at Sevilleta. At each site, two\n rainfall manipulations and ambient controls were established in 2013\n (n=10). Treatments included extreme drought (-66% rainfall\n reduction) and delayed monsoon (precipitation captured during\n July-August and reapplied during September-October). Aboveground\n species composition was assessed and composite soil samples were\n collected in 2017, five years after the experiment started. Seed\n bank composition was evaluated using the seedling emergence method.\n Rainfall treatments increased aboveground species richness at both\n sites, and seed bank richness only in the blue grama community.\n Vegetation cover was reduced by both rainfall manipulations, but\n seed bank density increased or remained the same compared with\n controls. In aboveground vegetation, cover of annual and perennial\n forbs increased, and dominant perennial grasses decreased. In the\n soil seed bank, species composition was similar among all treatments\n and was dominated by annual and perennial forbs. The seed bank was\n more resistant to drought than aboveground vegetation. Because seed\n banks enhance long-term community stability, their drought\n resistance plays an important role in maintaining ecosystem\n processes during and following drought in these grassland\n communities."]}
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Field-Collected Spectral Reflectance of Dominant Vegetation at the Sevilleta National Wildlife Refuge
{"Abstract":["This dataset includes field-collected spectral reflectance of\n dominant vegetation species in grassland and shrubland at the\n Sevilleta National Wildlife Refuge collected monthly May \u2013 September\n 2019. A spectroradiometer was used to collect the percent spectral\n reflectance of electromagnetic radiation (range 400-2500nm) of a\n sample of dominant vegetation species ("spectra"),\n yielding a spectral curve for each species. At least ten individuals\n per species were sampled. These data form a spectral library which\n was used to calibrate a multiple-endmember spectral mixture analysis\n (MESMA) of satellite imagery of the Sevilleta NWR, as part of an\n ongoing collaboration between the LTER and the Center for the\n Advancement of Spatial Informatics Research and Education (ASPIRE).\n Ultimately, we aim to produce fractional images of green vegetation,\n non-photosynthetic vegetation, bare soil, and shade to form a\n synoptic thirty-year record of vegetation dynamics at the Refuge.\n The spectral library can be referenced by future researchers using\n remote sensing methods to examine vegetation dynamics at the\n Sevilleta NWR."]}
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- Award ID(s):
- 1655499
- PAR ID:
- 10424100
- Publisher / Repository:
- Environmental Data Initiative
- Date Published:
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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Desert grassland vegetation is a key resource upon which rangelands in the southwestern US are built, and managing these ecosystems remains a critical challenge today. This experimental fire seasonality research project, in collaboration with the USFWS, USFS Rocky Mountain Research Station, and the Sevilleta LTER, is intended to provide land management agencies with information about vegetation recovery following fire under different seasonal conditions and burning treatments. This experimental research will enable the FWS to more effectively set project objectives for prescribed burning on the Sevilleta NWR to benefit not only wildlife habitat, but to better align the timing and intensity of fire to benefit the reestablishment of the dominant native grama grasses Bouteloua eriopoda and B. gracilis. Since its creation in 1973, management has been devoted to restoring the Sevilleta NWR to the natural conditions that might have been seen around the turn of the century. The Sevilleta NWR is an ideal place for research because climatic conditions, plant species composition and net primary production following wildfire have been well documented by the Sevilleta LTER. Additional experimental research is needed, however, to better inform managers about the timing and use of fire as an ecosystem restoration and management tool. This is an on-going, long-term experiment under the auspices of the Sevilleta LTER program.more » « less
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Humans are creating significant global environmental change, including shifts in climate, increased nitrogen (N) deposition, and the facilitation of species invasions. A multi-factorial field experiment is being performed in an arid grassland within the Sevilleta National Wildlife Refuge (NWR) to simulate increased nighttime temperature, higher N deposition, and heightened El Niño frequency (which increases winter precipitation by an average of 50%). The purpose of the experiment is to better understand the potential effects of environmental drivers on grassland community composition, aboveground net primary production and soil respiration. The focus is on the response of two dominant grasses (Bouteloua gracilis and B eriopoda), in an ecotone near their range margins and thus these species may be particularly susceptible to global environmental change. It is hypothesized that warmer summer temperatures and increased evaporation will favor growth of black grama (Bouteloua eriopoda), a desert grass, but that increased winter precipitation and/or available nitrogen will favor the growth of blue grama (Bouteloua gracilis), a shortgrass prairie species. Treatment effects on limiting resources (soil moisture, nitrogen availability, species abundance, and net primary production (NPP) are all being measured to determine the interactive effects of key global change drivers on arid grassland plant community dynamics and ecosystem processes. On 4 August 2009 lightning ignited a ~3300 ha wildfire that burned through the experiment and its surroundings. Because desert grassland fires are patchy, not all of the replicate plots burned in the wildfire. Therefore, seven days after the wildfire was extinguished, the Sevilleta NWR Fire Crew thoroughly burned the remaining plots allowing us to assess experimentally the effects of interactions among multiple global change presses and a pulse disturbance on post-fire grassland dynamics. This data set provides soil N availability in each plot of the warming experiment for the monsoon season (also see SEV176).more » « less
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