Description: <DIV STYLE="text-align:Left;"><DIV><DIV><P><SPAN>Percent tree canopy cover is a measure of local tree density that has a variety of applications in wildlife habitat analysis, fire behavior modeling, carbon accounting, and hydrologic analysis. Using medium spatial resolution imagery (30m) from Landsat, we have produced consistent, seamless per-pixel estimates of percent tree canopy cover ranging from 0 to 100 percent. This dataset is part of the larger National Land Cover Database (NLCD) that also includes information on land cover, percent imperviousness, and percent shrub/grass. The NLCD effort is coordinated by a partnership of federal agencies called the Multi-Resolution Land Characteristics (MRLC) Consortium (</SPAN><A href="http://www.mrlc.gov" STYLE="text-decoration:underline;"><SPAN><SPAN>www.mrlc.gov</SPAN></SPAN></A><SPAN>).</SPAN></P><P><SPAN>The U.S. Forest Service (USFS) built multiple versions of percent tree canopy cover data, including the tree canopy cover data that are included with the NLCD. The NLCD tree canopy cover data were designed as an integrated data stack for users in the NLCD community who are in need of coordinated datasets/layers that have the characteristic of “Time 1 TCC + change in TCC = Time 2 TCC”. </SPAN></P><P><SPAN>In addition to the NLCD tree canopy cover products, the USFS built and distributes “Analytical” and “Cartographic” versions of the tree canopy cover products. The “Analytical” version of the USFS tree canopy cover data prioritizes objectivity and statistics over visual appearance of the product. The “Cartographic” version of the USFS tree canopy cover data includes masking of some of the TCC values output from the modeling process, and it prioritizes the visual appearance of the TCC maps for cartographic uses. The “Analytic” and “Cartographic” versions of the datasets were documented and are described in more detail and available at </SPAN><A href="https://data.fs.usda.gov/geodata/rastergateway/treecanopycover/" STYLE="text-decoration:underline;"><SPAN><SPAN>https://data.fs.usda.gov/geodata/rastergateway/treecanopycover/</SPAN></SPAN></A><SPAN><SPAN>, while the NLCD tree canopy cover products are available through the Multi-Resolution Land Characteristics Consortium (MRLC) at </SPAN></SPAN><A href="http://www.mrlc.gov" STYLE="text-decoration:underline;"><SPAN><SPAN>www.mrlc.gov</SPAN></SPAN></A><SPAN><SPAN>.</SPAN></SPAN></P></DIV></DIV></DIV>
Copyright Text: Funding for this project was provided by the U.S. Forest Service (USFS). RedCastle Resources, Inc. produced the dataset under contract to the USFS Geospatial Technology and Applications Center.
Description: Quantifying Western U.S. shrublands as a series of fractional components with remote sensing provides a new way to understand these changing ecosystems. The USGS NLCD team in collaboration with the BLM has produced the most comprehensive remote sensing-based quantification of Western U.S. shrublands to date. Nine shrubland ecosystem components, including percent shrub, sagebrush (Artemisia spp), big sagebrush, herbaceous, annual herbaceous, litter, and bare ground cover, along with sagebrush and shrub heights, were quantified at 30-m resolution by mapping region. Each region required extensive ground measurement for model training and validation, two scales of remote sensing data from commercial high-resolution satellites and Landsat 8, and regression tree modeling to create component predictions. In the mapped portion (1,946,100 km²) of the total study area (2,557,556 km²), bare ground averaged 46.8%, shrub 14.4%, sagebrush 4.4%, big sagebrush 3.1%, herbaceous 22.8%, annual herbaceous 4.3% and litter 15.6%. Shrub height averaged 39.8 cm and sagebrush height 10.5 cm. Component accuracies using independent validation averaged R² values of 0.46, RMSE of 10.37 and nRMSE of 0.12, and cross validation averaged R² values of 0.72, RMSE of 5.09 and nRMSE of 0.062. Component composition strongly diverges by level III ecoregions, where 13 of 22 ecoregions are bare ground dominant, 8 are herbaceous dominant, and one is shrub dominant. Sagebrush physically covers 86,219 km², or 4.4%, of our study area, but it is present in 835,507 km², or 42.9%, of the non-masked area of our study area, underscoring its widespread distribution. Fractional component maps will be integrated into the 2016 National Land Cover Database (NLCD). Component products can be downloaded from www.mrlc.gov.
Copyright Text: U.S. Geological Survey (USGS)
Bureau of Land Management (BLM)
Description: Quantifying Western U.S. shrublands as a series of fractional components with remote sensing provides a new way to understand these changing ecosystems. The USGS NLCD team in collaboration with the BLM has produced the most comprehensive remote sensing-based quantification of Western U.S. shrublands to date. Nine shrubland ecosystem components, including percent shrub, sagebrush (Artemisia spp), big sagebrush, herbaceous, annual herbaceous, litter, and bare ground cover, along with sagebrush and shrub heights, were quantified at 30-m resolution by mapping region. Each region required extensive ground measurement for model training and validation, two scales of remote sensing data from commercial high-resolution satellites and Landsat 8, and regression tree modeling to create component predictions. In the mapped portion (1,946,100 km²) of the total study area (2,557,556 km²), bare ground averaged 46.8%, shrub 14.4%, sagebrush 4.4%, big sagebrush 3.1%, herbaceous 22.8%, annual herbaceous 4.3% and litter 15.6%. Shrub height averaged 39.8 cm and sagebrush height 10.5 cm. Component accuracies using independent validation averaged R² values of 0.46, RMSE of 10.37 and nRMSE of 0.12, and cross validation averaged R² values of 0.72, RMSE of 5.09 and nRMSE of 0.062. Component composition strongly diverges by level III ecoregions, where 13 of 22 ecoregions are bare ground dominant, 8 are herbaceous dominant, and one is shrub dominant. Sagebrush physically covers 86,219 km², or 4.4%, of our study area, but it is present in 835,507 km², or 42.9%, of the non-masked area of our study area, underscoring its widespread distribution. Fractional component maps will be integrated into the 2016 National Land Cover Database (NLCD). Component products can be downloaded from www.mrlc.gov.
Copyright Text: U.S. Geological Survey (USGS)
Bureau of Land Management (BLM)
Description: The U.S. Geological Survey (USGS), in partnership with several federal agencies, has developed and released four
National Land Cover Database (NLCD) products over the past two decades: NLCD 1992, 2001, 2006, and 2011.
These products provide spatially explicit and reliable information on the Nation’s land cover and land cover
change. To continue the legacy of NLCD and further establish a long-term monitoring capability for the Nation’s
land resources, the USGS has designed a new generation of NLCD products named NLCD 2016. The NLCD 2016
design aims to provide innovative, consistent, and robust methodologies for production of a multi-temporal land
cover and land cover change database from 2001 to 2016 at 2–3-year intervals. Comprehensive research was
conducted and resulted in developed strategies for NLCD 2016: a streamlined process for assembling and preprocessing
Landsat imagery and geospatial ancillary datasets; a multi-source integrated training data development
and decision-tree based land cover classifications; a temporally, spectrally, and spatially integrated land
cover change analysis strategy; a hierarchical theme-based post-classification and integration protocol for
generating land cover and change products; a continuous fields biophysical parameters modeling method; and
an automated scripted operational system for the NLCD 2016 production. The performance of the developed
strategies and methods were tested in twenty World Reference System-2 path/row throughout the conterminous
U.S. An overall agreement ranging from 71% to 97% between land cover classification and reference data was
achieved for all tested area and all years. Results from this study confirm the robustness of this comprehensive
and highly automated procedure for NLCD 2016 operational mapping.
Questions about the NLCD 2016 land cover product can be directed to the NLCD 2016 land cover mapping team at USGS EROS, Sioux Falls, SD (605) 594-6151 or mrlc@usgs.gov. See included spatial metadata for more details.
Description: Quantifying Western U.S. shrublands as a series of fractional components with remote sensing provides a new way to understand these changing ecosystems. The USGS NLCD team in collaboration with the BLM has produced the most comprehensive remote sensing-based quantification of Western U.S. shrublands to date. Nine shrubland ecosystem components, including percent shrub, sagebrush (Artemisia spp), big sagebrush, herbaceous, annual herbaceous, litter, and bare ground cover, along with sagebrush and shrub heights, were quantified at 30-m resolution by mapping region. Each region required extensive ground measurement for model training and validation, two scales of remote sensing data from commercial high-resolution satellites and Landsat 8, and regression tree modeling to create component predictions. In the mapped portion (1,946,100 km²) of the total study area (2,557,556 km²), bare ground averaged 46.8%, shrub 14.4%, sagebrush 4.4%, big sagebrush 3.1%, herbaceous 22.8%, annual herbaceous 4.3% and litter 15.6%. Shrub height averaged 39.8 cm and sagebrush height 10.5 cm. Component accuracies using independent validation averaged R² values of 0.46, RMSE of 10.37 and nRMSE of 0.12, and cross validation averaged R² values of 0.72, RMSE of 5.09 and nRMSE of 0.062. Component composition strongly diverges by level III ecoregions, where 13 of 22 ecoregions are bare ground dominant, 8 are herbaceous dominant, and one is shrub dominant. Sagebrush physically covers 86,219 km², or 4.4%, of our study area, but it is present in 835,507 km², or 42.9%, of the non-masked area of our study area, underscoring its widespread distribution. Fractional component maps will be integrated into the 2016 National Land Cover Database (NLCD). Component products can be downloaded from www.mrlc.gov.
Copyright Text: U.S. Geological Survey (USGS)
Bureau of Land Management (BLM)
Description: Quantifying Western U.S. shrublands as a series of fractional components with remote sensing provides a new way to understand these changing ecosystems. The USGS NLCD team in collaboration with the BLM has produced the most comprehensive remote sensing-based quantification of Western U.S. shrublands to date. Nine shrubland ecosystem components, including percent shrub, sagebrush (Artemisia spp), big sagebrush, herbaceous, annual herbaceous, litter, and bare ground cover, along with sagebrush and shrub heights, were quantified at 30-m resolution by mapping region. Each region required extensive ground measurement for model training and validation, two scales of remote sensing data from commercial high-resolution satellites and Landsat 8, and regression tree modeling to create component predictions. In the mapped portion (1,946,100 km²) of the total study area (2,557,556 km²), bare ground averaged 46.8%, shrub 14.4%, sagebrush 4.4%, big sagebrush 3.1%, herbaceous 22.8%, annual herbaceous 4.3% and litter 15.6%. Shrub height averaged 39.8 cm and sagebrush height 10.5 cm. Component accuracies using independent validation averaged R² values of 0.46, RMSE of 10.37 and nRMSE of 0.12, and cross validation averaged R² values of 0.72, RMSE of 5.09 and nRMSE of 0.062. Component composition strongly diverges by level III ecoregions, where 13 of 22 ecoregions are bare ground dominant, 8 are herbaceous dominant, and one is shrub dominant. Sagebrush physically covers 86,219 km², or 4.4%, of our study area, but it is present in 835,507 km², or 42.9%, of the non-masked area of our study area, underscoring its widespread distribution. Fractional component maps will be integrated into the 2016 National Land Cover Database (NLCD). Component products can be downloaded from www.mrlc.gov.
Copyright Text: U.S. Geological Survey (USGS)
Bureau of Land Management (BLM)