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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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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.
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This set of sixteen Landsat Thematic Mapper (TM)and Operational Land Imager (OLI)(Path 014 and Rows 032 and 033) surface reflectance data sets were collected between 2000 and 2015. This data presents a time-series analysis that uses linear spectral unmixing of composite Normalized Difference Vegetation Index, Normalized Difference Water Index, and Normalized Difference Soil Index data, to estimate the percentages of marsh vegetation, water, and exposed marsh substrate on the New Jersey intracoastal marshes. We used the composition of the marshes in terms of the percentage of marsh vegetation, water, and marsh substrate to produce Marsh Surface Condition Index (MSCI) maps consisting of three classes of marshes: severely...
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These data are aerial image-derived, classification maps of tamarisk (Tamarisk spp.) in the riparian zone of the Colorado River from Glen Canyon Dam to Separation Canyon, a total river distance of 412 km. The classification maps are published in GIS vector format. Two maps are published: 1) a classification of tamarisk from a 0.2 m resolution multispectral image dataset acquired in May 2009 (Tamarisk Classification 2009), and 2) a classification of tamarisk impacted by the tamarisk beetle (Diorhabda carinulata) from a 0.2 m resolution multispectral image dataset acquired in May 2013 (Beetle Impact Classification 2013). Tamarisk presence in 2009 was classified using the Mahalanobis Distance method with a total of...
This USGS Data Release represents geospatial data sets which were created to produce an Unvegetated to Vegetated Ratio (UVVR) for coastal wetlands of the conterminous United States (2014-2018). The following listed image products were generated 1) Annual spatial datasets (rasters) from 2014 to 2018 each containing 4 bands (Band 1: Unvegetated land fraction; Band 2: Vegetated land fraction; Band 3: Water fraction; Band 4: UVVR clipped into 3 coastal regions (Atlantic (ATL) Gulf of Mexico (GOM) and Pacific (PAC). 2) Calibration/Validation Datasets - datasets which were used in the calibration and validation of the above datasets 3) Mean of masked, multiyear composite - Mean vegetated fraction in coastal wetlands in...
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These are two land cover datasets derived from Landsat Thematic Mapper and Operational Land Imager (spatial resolution 30-m)Path 014 and Rows 032 and 033 surface reflectance data collected on July 14, 2011 and July 19, 2013, before and after Hurricane Sandy made landfall near Brigantine, New Jersey on October 29, 2012. The two land cover data sets provide a means of evaluating the effect of Hurricane Sandy of data sets collected at times that represent or approach peak vegetation growth. The most accurate results of the land cover classification are based on twelve classes, some of which occur adjacent to the marshes but not on the New Jersey intracoastal marshes. Twelve classes were used in the supervised maximum...
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This USGS Data Release represents geospatial data sets that were created for the analysis of the effect of Hurricane Sandy on New Jersey Atlantic Coastal Marshes. The following listed image products were generated: 1) Fifteen marsh surface condition index (MSCI) data sets were calculated from yearly summer collections of ETM+ image data from 2000 to 2015. Three classes described the results of the MSCI mapping; classs1-severely impacted, class 2-moderately impacted, and class 3-intact marsh. 2) Marsh change data product using Landsat images of July 14, 2011 (before) and July 19, 2013 (after) Hurricane Sandy is based on the difference in the percentage of vegetation. It shows a pattern of an increasing loss of marsh...
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The change detection data is the classified difference in the percentage of vegetation on the July 14, 2011 Landsat Thematic Mapper(TM) data set collected before Hurricane Sandy and the July 19, 2013 Landsat Operational Land Imager (OLI)data set collected after Hurricane Sandy. Hurricane Sandy made landfall near Brigandine, New Jersey on October 29, 2012. The actual difference in the percentage of vegetation is used in the calculation, not the three-class classification that is the basis of the Marsh Surface Condition Index data. The eleven classes consist of five classes (5-20%,>20%-40%,>40%-60%,>60%-80%,>80%)with decreases in the percentage of vegetation cover after Hurricane Sandy, Three classes (5-20%,>20%-40%,>40%-60%)with...
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The Green Wave Hypothesis posits that herbivore migration manifests in response to waves of spring green-up (i.e., green-wave surfing). Nonetheless, empirical support for the Green Wave Hypothesis is mixed, and a framework for understanding variation in surfing is lacking. In a population of migratory mule deer (Odocoileus hemionus), 31% surfed plant phenology in spring as well as a theoretically perfect surfer, and 98% surfed better than random. Green-wave surfing varied among individuals, and was unrelated to age or energetic state. Instead, the greenscape, which we define as the order, rate, and duration of green-up along migratory routes, was the primary factor influencing surfing. Our results indicate that...
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These raster and tabular data were compiled to develop time series data of the lower Colorado River (LCR) vegetation greenness, water use, and phenology since the year 2000. An objective of our study was to evaluate short and long-term effects of drought and biocontrol on LCR riparian and aquatic ecosystems south of Hoover Dam. These data represent spatially explicit average Enhanced Vegetation Index (EVI2) derived evapotranspiration (ET) difference, and scaled normalized difference vegetation index (NDVI*) difference maps between two decades (2000 to 2010 and 2011 to 2020) and two 5 year periods (2000 to 2005 and 2016 to 2020). The time-series period statistics data provide estimates of the riparian woodland area...
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These normalized difference vegetation index (NDVI) raster data were compiled to develop time series data of the lower Colorado River (LCR) riparian corridor vegetation greenness and phenology since the year 2000. An objective of our study was to evaluate short and long-term effects of drought and biocontrol on LCR riparian and aquatic ecosystems south of Hoover Dam. These data represent spatially explicit scaled normalized difference vegetation index (NDVI*) difference maps between two decades (2000 to 2010 and 2011 to 2020) and two 5 year periods (2000 to 2005 and 2016 to 2020). NDVI* is an additional correction to the NDVI to account for the illumination conditions; it is a processing correction step to improve...
Mapping salt-affected soils in remote rangelands is challenging. We used Landsat 7 ETM data to facilitate digital mapping of gypsic and natric soil areas in the upper Colorado River drainage. Optimum index factor band combinations were used to explore the scene. Normalized difference ratio models and threshold values were developed by comparing spectral signatures with gypsic and natric soil areas verifi ed in the fi eld. Gypsic soil areas were mapped using the normalized difference ratio of Bands 5 and 7 with a threshold >0.11, probably related to the spectral refl ectance of gypsum within a few centimeters of the surface. All sites predicted to be gypsic soil areas were determined to be gypsic by fi eld assessment,...
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These full time-series period statistics data were compiled for monitoring riparian zone trends and changes in the lower Colorado as part of a study to document riparian ecosystem health and its water use. Our study evaluated the short and long-term effects on the river's vegetation of drought and hydrological processes in this dryland region. Because of the landscape changes, we explored remote sensing-based change analysis techniques and data to develop time series data of the Colorado River riparian corridor vegetation greenness, phenology, and water use since the year 2000. We divided the river into five Reaches (R3..R7) to separate between the different land covers, management conditions, and general geospatial...


map background search result map search result map Average Normalized Difference Vegetation Index (NDVI) for the western United States (1989-2002) Mean of the Top Ten Percent of NDVI Values in the Yuma Proving Ground during Monsoon Season, 1986-2011 Analysis of the effect of Hurricane Sandy on New Jersey Atlantic coastal marshes based on landsat thematic mapper and operational land imager data: 2000-2015 Marsh surface condition index dataset Marsh change dataset Land cover classification dataset Daily Surfing Remote sensing derived maps of tamarisk (2009) and beetle impacts (2013) along 412 km of the Colorado River in the Grand Canyon, Arizona Data supporting Landsat time series assessment of invasive annual grasses following energy development An Unvegetated to Vegetated Ratio (UVVR) for coastal wetlands of the Conterminous United States (2014-2018) Colorado River Project: A compilation of vegetation indices, phenology assessment metrics, estimates of evapotranspiration and change maps for five reaches between Hoover and Morelos Dams on the Lower Colorado River, for nearly the last two decades Colorado River Delta Project: Growing Season Normalized Difference Vegetation Index (NDVI) Difference Maps Colorado River Delta Project: River reach (3-7) full time-series period statistics computed for Landsat 5, Landsat 7 and Landsat 8 data Mean of the Top Ten Percent of NDVI Values in the Yuma Proving Ground during Monsoon Season, 1986-2011 Colorado River Project: A compilation of vegetation indices, phenology assessment metrics, estimates of evapotranspiration and change maps for five reaches between Hoover and Morelos Dams on the Lower Colorado River, for nearly the last two decades Colorado River Delta Project: Growing Season Normalized Difference Vegetation Index (NDVI) Difference Maps Colorado River Delta Project: River reach (3-7) full time-series period statistics computed for Landsat 5, Landsat 7 and Landsat 8 data Analysis of the effect of Hurricane Sandy on New Jersey Atlantic coastal marshes based on landsat thematic mapper and operational land imager data: 2000-2015 Marsh surface condition index dataset Marsh change dataset Land cover classification dataset Daily Surfing Remote sensing derived maps of tamarisk (2009) and beetle impacts (2013) along 412 km of the Colorado River in the Grand Canyon, Arizona Data supporting Landsat time series assessment of invasive annual grasses following energy development Average Normalized Difference Vegetation Index (NDVI) for the western United States (1989-2002) An Unvegetated to Vegetated Ratio (UVVR) for coastal wetlands of the Conterminous United States (2014-2018)