The U.S. Geological Survey (USGS) has generated land surface form classes for the contiguous United States. These land surface form classes were created as part of an effort to map standardized, terrestrial ecosystems for the nation using a classification developed by NatureServe (Comer and others, 2003). Ecosystem distributions were modeled using a biophysical stratification approach developed for South America (Sayre and others, 2008) and now being implemented globally (Sayre and others, 2007). Land surface forms strongly influence the differentiation and distribution of terrestrial ecosystems, and are one of the key input layers in the ecosystem delineation process. The methodology used to produce these land surface form classes was developed by the Missouri Resource Assessment Partnership (MoRAP). MoRAP made modifications to Hammond's (1964a, 1964b) land surface form classification, which allowed the use of 30-meter source data and a 1 km2 window for neighborhood analysis (True 2002, True and others, 2000). While Hammond's methodology was based on three variables, slope, local relief, and profile type, MoRAP's methodology uses only slope and local relief (True 2002). Slope is classified as gently sloping or not gently sloping using a slope threshold of 8%, local relief is classified into five classes (0-15m, 15-30m, 30-90m, 90-150m, and >150m), and eight landform classes (flat plains, smooth plains, irregular plains, escarpments, low hills, hills, breaks, and low mountains) were derived by combining slope class and local relief. The USGS implementation of the MoRAP methodology was executed using the USGS 30-meter National Elevation Dataset (NED) and an existing USGS slope dataset. In this implementation, a new land surface form class, the high mountains/deep canyons class, was identified by using an additional local relief class (> 400m). The drainage channels class was derived independently from the other land surface form classes. This class was derived using two of Andrew Weiss's slope position classes, "valley" and "lower slope" (Weiss 2001, Jenness 2006). The USGS implemented Weiss's algorithm using the 30-meter NED and a 1 km2 neighborhood analysis window. The resultant drainage channel class was combined into the final land surface forms dataset.

The U.S. Geological Survey (USGS) modeled the distribution of terrestrial ecosystems for the contiguous United States using a standardized, deductive approach to associate unique physical environments with ecological systems characterized in NatureServe's Ecological Systems of the United States classification (Comer et al., 2003). This approach was first developed for South America (Sayre et al., 2008) and is now being implemented globally (Sayre et al., 2007). Unique physical environments were delineated from a massive biophysical stratification of the nation into the major structural components of ecosystems: biogeographic regions (Cress et al., 2008c), land surface forms (Cress et al., 2008a), surficial lithology (Cress et al., 2008d), and topographic moisture potential (Cress et al., 2008b). Each of these structural components was mapped for the contiguous United States and then spatially combined to produce ecosystem structural footprints which represented unique abiotic (physical) environments. Among 49,168 unique structural footprint classes, 13,482 classes which met a minimum pixel count threshold (20,000 pixels) were aggregated into 419 NatureServe ecosystems through semi-automated labeling process using rule set formulations for attribution of each ecosystem. UPDATE: A newer terrestrial ecosystems datalayer, "World Terrestrial Ecosystems (WTE) 2020", is now available at: https://doi.org/10.5066/P9DO61LP. This datalayer is a global raster dataset at a 250 m spatial resolution where 431 ecosystem types are identified and mapped. Each ecosystem type is a unique combination of vegetation/land cover, climate region, and landform.

The U.S. Geological Survey (USGS) modeled the distribution of terrestrial ecosystems for the contiguous United States using a standardized, deductive approach to associate unique physical environments with ecological systems characterized in NatureServe's Ecological Systems of the United States classification (Comer et al., 2003). This approach was first developed for South America (Sayre et al., 2008) and is now being implemented globally (Sayre et al., 2007). Unique physical environments were delineated from a massive biophysical stratification of the nation into the major structural components of ecosystems: biogeographic regions (Cress et al., 2008c), land surface forms (Cress et al., 2008a), surficial lithology (Cress et al., 2008d), and topographic moisture potential (Cress et al., 2008b). Each of these structural components was mapped for the contiguous United States and then spatially combined to produce ecosystem structural footprints which represented unique abiotic (physical) environments. Among 49,168 unique structural footprint classes, 13,482 classes which met a minimum pixel count threshold (20,000 pixels) were aggregated into 419 NatureServe ecosystems through semi-automated labeling process using rule set formulations for attribution of each ecosystem. UPDATE: A newer terrestrial ecosystems datalayer, "World Terrestrial Ecosystems (WTE) 2020", is now available at: https://doi.org/10.5066/P9DO61LP. This datalayer is a global raster dataset at a 250 m spatial resolution where 431 ecosystem types are identified and mapped. Each ecosystem type is a unique combination of vegetation/land cover, climate region, and landform.

The U.S. Geological Survey (USGS) modeled the distribution of terrestrial ecosystems for the contiguous United States using a standardized, deductive approach to associate unique physical environments with ecological systems characterized in NatureServe's Ecological Systems of the United States classification (Comer et al., 2003). This approach was first developed for South America (Sayre et al., 2008) and is now being implemented globally (Sayre et al., 2007). Unique physical environments were delineated from a massive biophysical stratification of the nation into the major structural components of ecosystems: biogeographic regions (Cress et al., 2008c), land surface forms (Cress et al., 2008a), surficial lithology (Cress et al., 2008d), and topographic moisture potential (Cress et al., 2008b). Each of these structural components was mapped for the contiguous United States and then spatially combined to produce ecosystem structural footprints which represented unique abiotic (physical) environments. Among 49,168 unique structural footprint classes, 13,482 classes which met a minimum pixel count threshold (20,000 pixels) were aggregated into 419 NatureServe ecosystems through semi-automated labeling process using rule set formulations for attribution of each ecosystem. UPDATE: A newer terrestrial ecosystems datalayer, "World Terrestrial Ecosystems (WTE) 2020", is now available at: https://doi.org/10.5066/P9DO61LP. This datalayer is a global raster dataset at a 250 m spatial resolution where 431 ecosystem types are identified and mapped. Each ecosystem type is a unique combination of vegetation/land cover, climate region, and landform.

The U.S. Geological Survey (USGS) modeled the distribution of terrestrial ecosystems for the contiguous United States using a standardized, deductive approach to associate unique physical environments with ecological systems characterized in NatureServe's Ecological Systems of the United States classification (Comer et al., 2003). This approach was first developed for South America (Sayre et al., 2008) and is now being implemented globally (Sayre et al., 2007). Unique physical environments were delineated from a massive biophysical stratification of the nation into the major structural components of ecosystems: biogeographic regions (Cress et al., 2008c), land surface forms (Cress et al., 2008a), surficial lithology (Cress et al., 2008d), and topographic moisture potential (Cress et al., 2008b). Each of these structural components was mapped for the contiguous United States and then spatially combined to produce ecosystem structural footprints which represented unique abiotic (physical) environments. Among 49,168 unique structural footprint classes, 13,482 classes which met a minimum pixel count threshold (20,000 pixels) were aggregated into 419 NatureServe ecosystems through semi-automated labeling process using rule set formulations for attribution of each ecosystem. UPDATE: A newer terrestrial ecosystems datalayer, "World Terrestrial Ecosystems (WTE) 2020", is now available at: https://doi.org/10.5066/P9DO61LP. This datalayer is a global raster dataset at a 250 m spatial resolution where 431 ecosystem types are identified and mapped. Each ecosystem type is a unique combination of vegetation/land cover, climate region, and landform.

The U.S. Geological Survey (USGS) modeled the distribution of terrestrial ecosystems for the contiguous United States using a standardized, deductive approach to associate unique physical environments with ecological systems characterized in NatureServe's Ecological Systems of the United States classification (Comer et al., 2003). This approach was first developed for South America (Sayre et al., 2008) and is now being implemented globally (Sayre et al., 2007). Unique physical environments were delineated from a massive biophysical stratification of the nation into the major structural components of ecosystems: biogeographic regions (Cress et al., 2008c), land surface forms (Cress et al., 2008a), surficial lithology (Cress et al., 2008d), and topographic moisture potential (Cress et al., 2008b). Each of these structural components was mapped for the contiguous United States and then spatially combined to produce ecosystem structural footprints which represented unique abiotic (physical) environments. Among 49,168 unique structural footprint classes, 13,482 classes which met a minimum pixel count threshold (20,000 pixels) were aggregated into 419 NatureServe ecosystems through semi-automated labeling process using rule set formulations for attribution of each ecosystem. UPDATE: A newer terrestrial ecosystems datalayer, "World Terrestrial Ecosystems (WTE) 2020", is now available at: https://doi.org/10.5066/P9DO61LP. This datalayer is a global raster dataset at a 250 m spatial resolution where 431 ecosystem types are identified and mapped. Each ecosystem type is a unique combination of vegetation/land cover, climate region, and landform.

,This metadata is the documentation for the field soil observations, ecological site identification, and geomorphology characteristics collected by the Assessment, Inventory, and Monitoring (AIM) terrestrial program between 2012 and 2021 in 14 states of the western United States. The AIM program is conducted by the Bureau of Land Management (BLM)’s and provides information to guide site-specific management of ecosystem functions and services. There are 31,267 monitoring plots (79% of plots) with identified ecological sites and 29,228 plots (74% of plots) containing soil morphology descriptions of soil horizons examined in excavated pits. While soil texture class is observed in most soil horizons (98%), rock fragment volume is the soil property with the least data availability (75%). The consistency of soil data (e.g., clay content observations within the ranges of texture classes) increases as a function of time following guidance in soil profile description training for AIM data collectors. Nearly 47% of AIM plots are found on gentle slopes of 0-5% steepness and on Flat/Plain and Hill/Mountain landscape types. The AIM database is a source of georeferenced soil and geomorphology information that can be used for land management and research on land potential, soil geography, and assessment of soil health indicators across the western United States.,Resources in this dataset:,,

This dataset provides the spatial distribution of vegetation types, soil carbon, and physiographic features in the Imnavait Creek area, Alaska. Specific attributes include vegetation, percent water, glacial geology, soil carbon, a digital elevation model (DEM), surficial geology and surficial geomorphology. Data are also provided on the research grids for georeferencing. The map data are from a variety of sources and encompass the period 1970-06-01 to 2015-08-31.

This dataset provides two 30-m resolution time series products of annual land cover classifications over the Arctic Boreal Vulnerability Experiment (ABoVE) core domain for each year of the period 1984-2014. The data are the annual dominant plant functional type in a given 30-m pixel derived from Landsat surface reflectance, landcover training data mapped across the ABoVE domain (using Random Forests modeling, with clustering and interpretation of field photography) and very high resolution imagery to assign land cover classifications. One product has a 15-class land cover classification that breaks out forest and shrub types into several additional classes; the other product provides a simplified, 10-class approach. Classification accuracy assessment results are provided per year. Assessments were based on a probability-based random sample of reference data that supported statistically robust estimation of areas and uncertainties in mapped areas.

The National Aggregates of Geospatial Data Collection: Population, Landscape, And Climate Estimates, Version 3 (PLACE III) data set contains estimates of national-level aggregations in urban, rural, and total designations of territorial extent and population size by biome, climate zone, coastal proximity zone, elevation zone, and population density zone, for 232 statistical areas (countries and other UN recognized territories). This data set is produced by the Columbia University Center for International Earth Science Information Network (CIESIN).