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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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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 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...
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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...
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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This product consists of 29 datasets of tabular data and associated metadata for watershed characteristics of 1,530 study sites of the Surface Water Trends (SWT) project of the U.S. Geological Survey’s (USGS) National Water Quality Program (NWQP). The project is conducting national studies of trends in water quality of streams and rivers for periods ranging from 10 to 40 years, between 1972 and 2012. The data here include both static and time-series characteristics. Static data include primarily physical characteristics which have changed little over this period, such as geology, soils, and topography. Time-series data represent characteristics which may or may not have changed over time, such as land use, agricultural...
Categories: Data; Types: Citation; Tags: Atmospheric Deposition, Basin Morphology, Census of Agriculture, Conterminous US, Crop Practices, All tags...
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These data were simulated using the SOILWAT model and were intended to characterize soil-water conditions at different ecological sites on the Southern Colorado Plateau. SOILWAT is a daily, site-specific, multi soil-layer, ecosystem water-balance model, driven by daily meteorology, as well as site soil texture and vegetation. The sites simulated correspond with Inventory and Monitoring (I&M) plots established by the National Park Service’s (NPS) Southern Colorado Plateau Network (SCPN), which were established to capture the range of ecosystem conditions present in this network. Plant communities of the Southern Colorado Plateau Network (SCPN) are a vital sign for this region, enhancing habitat, stabilizing soils,...
Normalized difference vegetation index (NDVI) is an indicator of vegetation health and density. High NDVI values generally correspond to dense vegetation and low NDVI values generally correspond to sparsely vegetated or barren areas. NDVI was calculated for pan-sharpened Landsat 8 Operational Land Imager images acquired on May 13, 2015 and May 15, 2016 for the region around Icy Bay, Alaska. NDVI results from 2015 were subtracted from results for 2016 to produce a change image. The change image can be used to assess changes in vegetation patterns resulting from a landslide that occurred near Tyndall Glacier in October, 2015 and generated a tsunami in Taan Fiord, an arm of Icy Bay. Positive change in NDVI generally...
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This data release includes data processing scripts, data products, and associated metadata for a novel remote-sensing based approach to assess resilience of spring-dependent ecosystems to inter-annual changes in water availability. This approach uses remotely-sensed Normalized Difference Vegetation Index (NDVI) to (1) delineate surface moisture zones (SMZs) in the vicinity of mapped springs in a semi-arid sage-steppe landscape, (2) derive quantitative indicators of the relative resilience of these SMZs to inter-annual changes in water availability, and (3) synthesize these indicators into an overall resilience score for each cluster of springs. Specifically, for 39 spring clusters mapped in the National Hydrography...


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 Watershed characteristics for study sites of the Surface Water Trends project, National Water Quality Program Delineation and characterization of remotely sensed vegetation conditions in spring-dependent ecosystems, Harney County, Oregon Daily Surfing Simulated Soil Water Potential in National Parks and Monuments of the Southern Colorado Plateau, 1915-2099—Data 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 Delineation and characterization of remotely sensed vegetation conditions in spring-dependent ecosystems, Harney County, Oregon 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 Simulated Soil Water Potential in National Parks and Monuments of the Southern Colorado Plateau, 1915-2099—Data Watershed characteristics for study sites of the Surface Water Trends project, National Water Quality Program Average Normalized Difference Vegetation Index (NDVI) for the western United States (1989-2002)