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To determine if invasive annual grasses increased around energy developments after the construction phase, we calculated an invasives index using Landsat TM and ETM+ imagery for a 34-year time period (1985-2018) and assessed trends for 1,755 wind turbines (from the U.S. Wind Turbine Database) installed between 1988 and 2013 in the southern California desert. The index uses the maximum normalized difference vegetation index (NDVI) for early season greenness (January-June), and mean NDVI (July-October) for the later dry season. We estimated the relative cover of invasive annuals each year at turbine locations and control sites and tested for changes before and after each turbine was installed. These data were used...
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Polygon locations of fire perimeters in the Sky Island mountain ranges in the Madrean Archipelago Ecoregion of the southwestern United States and northern Mexico. These fires occurred from 1985 to 2011 and were mapped using Landsat satellite imagery.
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Wildfires scorched 10 million acres across the United States in 2015, and for the first time on record, wildfire suppression costs topped $2 billion. Wildfire danger modeling is an important tool for understanding when and where wildfires will occur, and recent work by our team in the South Central United States has shown wildfire danger models may be improved by incorporating soil moisture information. Advancements in wildfire danger modeling may increase wildfire preparedness, and therefore decrease loss of life, property, and habitat due to wildfire. Still, soil moisture—an important determinant of wildfire risk—is not currently used for wildfire danger assessments because data are generally unavailable at the...
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Wildfire is a natural and essential process in forest ecosystems, but characteristics of fire regimes that have shaped these landscapes over long time scales are changing with climate change and human activities. In some places, changes in fire size, frequency, and severity threaten to degrade essential ecosystem services that produce clean air and water, fertile soil for crop and wood production, and habitat for plant and animal species. Hence, it is urgent to understand how both our actions and inactions contribute to the vulnerability of forest ecosystems and to develop management practices that help sustain and conserve vegetation and wildlife communities in vulnerable forest systems. Our project will address...
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This climate and vegetation index dataset was collected from readily available open source data, such as Landsat. The data represents points across the northern Colorado plateau. The vegetation type was defined based on U.S. Geological Survey ReGAP data. Using compositing techniques by season we developed a dataset of lag and legacy for each point. We could then look to understand how both lag and legacy impacted vegetation production across the time series. In this dataset we focus on the soil adjusted vegetation index (SAVI), the standardized precipitation and evapotranspiration index (SPEI), and precipitation. Included in this dataset are climate lags of 3,6,9 and 12 months. Additionally, the legacy construct...
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This dataset contains 10 classified raster images identifying the distribution and condition of biological soil crusts using high-resolution imagery from Unmanned Aerial Systems (UAS). Also included are: a supplemental accuracy report and accuracy matrix for each classified image, and all associated accessory files. These images are located in Beef Basin, Southeastern Utah, and focuses on two ecological site types: Semidesert Shallow Loam, and Upland Stony Loam ('Sagebrush' and 'Pinyon-Juniper') sites. Five 50 x 50 m field sites were established for a total of 10 sites.
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The practice of fire suppression across the western United States over the past century has led to dense forests, and when coupled with drought has contributed to an increase in large and destructive wildfires. Forest management efforts aimed at reducing flammable fuels through various fuel treatments can help to restore frequent fire regimes and increase forest resilience. Our research examines how different fuel treatments influenced burn severity and post-fire vegetative stand dynamics on the San Carlos Apache Reservation, in east-central Arizona, U.S.A. Our methods included the use of multitemporal remote sensing data and cloud computing to evaluate burn severity and post-fire vegetation conditions as well as...
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Woody plant encroachment and overall declines in perennial vegetation in dryland regions can alter ecosystem properties and indicate land degradation, but the causes of these shifts remain controversial. Determining how changes in the abundance and distribution of grass and woody plants are influenced by conditions that regulate water availability at a regional scale provides a baseline to which compare how management actions alter the composition of these vegetation types at a more local scale and can be used to predict future shifts under climate change. Using a remote sensing-based approach, we assessed the balance between grasses and woody plants and how climate and topo-edaphic conditions affected their abundances...
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This data release contains mapped UAS products and a spreadsheet of field plot observations for the paper: Havrilla, C.A. and M.L. Villarreal. 2024. Soil cover heterogeneity associated with biocrusts predicts patch-level plant diversity patterns. Landscape Ecology. Specifically the zipped folder contains a CSV of field data, classified Unoccupied Aerial Systems (UAS) imagery for 3 study plots and Soil Cover Heterogeneity maps generated from each of the classified maps.
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In the western U.S., rising temperatures and pronounced drought conditions pose significant challenges to public land managers. Widespread declines of multiple plant species have already been observed, providing insight into what the future could look like for vegetation in the region as conditions are projected to become warmer and drier. To understand how vulnerable western ecosystems are to drought, managers need to know which climatic and soil conditions cause habitats to change, and at what rate these changes may occur – important topics on which there is little available data. This project seeks to identify the vulnerability of habitats in the western U.S. to drought. Researchers will compare changes in...
    map background search result map search result map Assessing the Vulnerability of Dryland Ecosystems to Drought in the Western U.S. Data for Decadal shifts in grass and woody plant cover are driven by prolonged drying and modified by topo-edaphic properties Wildfire Probability Mapping Based on Regional Soil Moisture Models Dataset for 2013 Creek Fire Research Points, Pre- and Post-Fire Data, U.S. Geological Survey Mapped fire perimeters from the Sky Island Mountains of US and Mexico: 1985-2011 Dataset for climate legacy and lag effects on dryland plant communities in the southwestern U.S. Data supporting Landsat time series assessment of invasive annual grasses following energy development High-resolution object-based image classifications of biological soil crusts and vegetation (Beef Basin, Utah) Assessing Vulnerability of Vegetation and Wildlife Communities to Post-Fire Transformations to Guide Management of Southwestern Pine Forests and Woodlands UAS products and field data for biocrust soil heterogeneity research, Beef Basin, Utah High-resolution object-based image classifications of biological soil crusts and vegetation (Beef Basin, Utah) UAS products and field data for biocrust soil heterogeneity research, Beef Basin, Utah Dataset for 2013 Creek Fire Research Points, Pre- and Post-Fire Data, U.S. Geological Survey Data for Decadal shifts in grass and woody plant cover are driven by prolonged drying and modified by topo-edaphic properties Mapped fire perimeters from the Sky Island Mountains of US and Mexico: 1985-2011 Data supporting Landsat time series assessment of invasive annual grasses following energy development Dataset for climate legacy and lag effects on dryland plant communities in the southwestern U.S. Assessing Vulnerability of Vegetation and Wildlife Communities to Post-Fire Transformations to Guide Management of Southwestern Pine Forests and Woodlands Wildfire Probability Mapping Based on Regional Soil Moisture Models Assessing the Vulnerability of Dryland Ecosystems to Drought in the Western U.S.