Filters: Tags: Normalized difference vegetation index (X) > Extensions: Shapefile (X)

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Data supporting Landsat time series assessment of invasive annual grasses following energy development 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... Categories: Data; Types: Downloadable, Map Service, OGC WFS Layer, OGC WMS Layer, OGC WMS Service, Shapefile; Tags: California, California South, Google Earth Engine, Landsat, Normalized Difference Vegetation Index, All tags... USGS Science Data Catalog (SDC), desert ecosystems, ecology, energy development, energy resources, grassland ecosystems, grasslands, invasive species, nonindigenous species, time series, vegetation, wind energy, Fewer tags Mean of the Top Ten Percent of NDVI Values in the Yuma Proving Ground during Monsoon Season, 1986-2011 This study uses growth in vegetation during the monsoon season measured from LANDSAT imagery as a proxy for measured rainfall. NDVI values from 26 years of pre- and post-monsoon season Landsat imagery were derived across Yuma Proving Ground (YPG) in southwestern Arizona, USA. The LANDSAT imagery (1986-2011) was downloaded from USGS’s GlobeVis website (http://glovis.usgs.gov/). Change in NDVI was calculated within a set of 2,843 Riparian Area Polygons (RAPs) up to 1 km in length defined in ESRI ArcMap 10.2. Categories: Data; Types: Downloadable, Map Service, OGC WFS Layer, OGC WMS Layer, Shapefile; Tags: Arizona, Landsat TM, NDVI, Normalized Difference Vegetation Index, Sonoran Desert, All tags... Southwestern United States, USGS Science Data Catalog (SDC), Yuma Proving Ground, biota, climatologyMeteorologyAtmosphere, ephemeral stream channels, monsoon season, Fewer tags