Gap Analysis Project (GAP) habitat maps are predictions of the spatial distribution of suitable environmental and land cover conditions within the United States for individual species. Mapped areas represent places where the environment is suitable for the species to occur (i.e. suitable to support one or more life history requirements for breeding, resting, or foraging), while areas not included in the map are those predicted to be unsuitable for the species. While the actual distributions of many species are likely to be habitat limited, suitable habitat will not always be occupied because of population dynamics and species interactions. Furthermore, these maps correspond to midscale characterizations of landscapes, but individual animals may deem areas to be unsuitable because of presence or absence of fine-scale features and characteristics that are not represented in our models (e.g. snags, vernal pools, shrubby undergrowth). These maps are intended to be used at a 1:100,000 or smaller map scale. These habitat maps are created by applying a deductive habitat model to remotely-sensed data layers within a species’ range. The deductive habitat models are built by compiling information on species’ habitat associations and entering it into a relational database. Information is compiled from the best available characterizations of species’ habitat, which included species accounts in books and databases, primary peer-reviewed literature. The literature references for each species are included in the "Species Habitat Model Report" and "Machine Readable Habitat Database Parameters" files attached to each habitat map item in the repository. For all species, the compiled habitat information is used by a biologist to determine which of the ecological systems and land use classes represented in the National Gap Analysis Project’s (GAP) Land Cover Map Ver. 1.0 that species is associated with. The name of the biologist who conducted the literature review and assembled the modeling parameters is shown as the "editor" type contact for each habitat map item in the repository. For many species, information on other mapped factors that define the environment that is suitable is also entered into the database. These factors included elevation (i.e. minimum, maximum), proximity to water features, proximity to wetlands, level of human development, forest ecotone width, and forest edge; and each of these factors corresponded to a data layer that is available during the map production. The individual datasets used in the modeling process with these parameters are also made available in the ScienceBase Repository (see the end of this Summary section for details). The "Machine Readable Habitat Database Parameters" JSON file attached to each species habitat map item has an "input_layers" object that contains the specific parameter names and references (via Digital Object Identifier) to the input data used with that parameter. The specific parameters for each species were output from the database used in the modeling and mapping process to the "Species Habitat Model Report" and "Machine Readable Habitat Database Parameters" files attached to each habitat map item in the repository. The maps are generated using a python script that queries the model parameters in the database; reclassifies the GAP Land Cover Ver 1.0 and ancillary data layers within the species’ range; and combines the reclassified layers to produce the final 30m resolution habitat map. Map output is, therefore, not only a reflection of the ecological systems that are selected in the habitat model, but also any other constraints in the model that are represented by the ancillary data layers. Modeling regions were used to stratify the conterminous U.S. into six regions (Northwest, Southwest, Great Plains, Upper Midwest, Southeast, and Northeast). These regions allowed for efficient processing of the species distribution models on smaller, ecologically homogenous extents. The 2008 start date for the models represents the shift in focus from state and regional project efforts to a national one. At that point all of the datasets needed to be standardized across the national extent and the species list derived based on the current understanding of the taxonomy. The end date for the individual models represents when the species model was considered complete, and therefore reflects the current knowledge related to that species concept and the habitat requirements for the species. Versioning, Naming Conventions and Codes: A composite version code is employed to allow the user to track the spatial extent, the date of the ground conditions, and the iteration of the data set for that extent/date. For example, CONUS_2001v1 represents the spatial extent of the conterminous US (CONUS), the ground condition year of 2001, and the first iteration (v1) for that extent/date. In many cases, a GAP species code is used in conjunction with the version code to identify specific data sets or files (i.e. Cooper’s Hawk Habitat Map named bCOHAx_CONUS_2001v1_HabMap). This collection represents the first complete compilation of terrestrial vertebrate species models for the conterminous U.S. based on 2001 ground conditions. The taxonomic concept for the species model being presented is identified through the Integrated Taxonomic Information System – Taxonomic Serial Number. To provide a link to the NatureServe species information the NatureServe Element Code is provided for each species. The identifiers included for each species habitat map item in the repository include references to a vocabulary system in ScienceBase where definitions can be found for each type of identifier. Source Datasets Uses in Species Habitat Modeling: Gap Analysis Project Species Range Maps - Species ranges were used as model delimiters in predicted distribution models. https://www.sciencebase.gov/catalog/item/5951527de4b062508e3b1e79 Hydrologic Units - Modified 12-digit hydrologic units were used as the spatial framework for species ranges. https://www.sciencebase.gov/catalog/item/56d496eee4b015c306f17a42 Modeling regions - Used to stratify the conterminous U.S. into six ecologically homogeneous regions to facilitate efficient processing. https://www.sciencebase.gov/catalog/item/58b9b8cee4b03b285c07ddef Land Cover - Species were linked to individual map units to document habitat affinity in two ways. Primary map units are those land cover types critical for nesting, rearing young, and/or optimal foraging. Secondary or auxiliary map units are those land cover types generally not critical for breeding, but are typically used in conjunction with primary map units for foraging, roosting, and/or sub-optimal nesting locations. These map units are selected only when located within a specified distance from primary map units. https://www.sciencebase.gov/catalog/item/5540e2d7e4b0a658d79395db Human Impact Avoidance - Buffers around urban areas and roads were used to identify areas that would be suitable for urban exploitative species and unsuitable for urban avoiding species. https://www.sciencebase.gov/catalog/item/5540e099e4b0a658d79395d6 Forest & Edge Habitats - The land cover map was used to derive datasets of forest interior and ecotones between forest and open habitats. Forest edge https://www.sciencebase.gov/catalog/item/5540e3fce4b0a658d79395fe Forest/Open Woodland/Shrubland https://www.sciencebase.gov/catalog/item/5540e48fe4b0a658d7939600 Elevation Derivatives - Slope and aspect were used to constrain some of the southwestern models where those variables are good indicators of microclimates (moist north facing slopes) and local topography (cliffs, flats). For species with a documented relationship to altitude the elevation data was used to constrain the mapped distribution. Aspect https://www.sciencebase.gov/catalog/item/5540ec40e4b0a658d7939628 Slope https://www.sciencebase.gov/catalog/item/5540ebe2e4b0a658d7939626 Elevation https://www.sciencebase.gov/catalog/item/5540e111e4b0a658d79395d9 Hydrology - https://www.sciencebase.gov/catalog/item/5540eb44e4b0a658d7939624: A number of water related data layers were used to refine the species distribution including: water type (i.e. flowing, open/standing), distance to and from water, and stream flow and underlying gradient. The source for this data was the USGS National Hydrography Dataset (NHD)(USGS 2007). Hydrographic features were divided into three types: flowing water, open/standing water, and wet vegetation. Canopy Cover - Some species are limited to open woodlands or dense forest, the National Land Cover’s Canopy Cover dataset was used to constrain the species models based on canopy density. https://www.sciencebase.gov/catalog/item/5540eca9e4b0a658d793962b

The map graphic image at https://www.sciencebase.gov/catalog/file/get/63140561d34e36012efa2b7f?name=arsenic_map.png illustrates arsenic values, in micrograms per liter, for groundwater samples from about 31,000 wells and springs in 49 states compiled by the United States Geological Survey (USGS). The map graphic illustrates an updated version of figure 1 from Ryker (2001). Cited Reference: Ryker, S.J., Nov. 2001, Mapping arsenic in groundwater-- A real need, but a hard problem: Geotimes Newsmagazine of the Earth Sciences, v. 46 no. 11, p. 34-36 at http://www.agiweb.org/geotimes/nov01/feature_Asmap.html. An excel tabular data file, a txt file, along with a GIS shape file of arsenic concentrations (20,043 samples collected by the USGS) for a subset of the sites shown on the map. Samples were collected between 1973 and 2001 and are provided for download.

NOTE: A more current version of the Protected Areas Database of the United States (PAD-US) is available: PAD-US 3.0 https://doi.org/10.5066/P9Q9LQ4B. The USGS Protected Areas Database of the United States (PAD-US) is the nation's inventory of protected areas, including public land and voluntarily provided private protected areas, identified as an A-16 National Geospatial Data Asset in the Cadastre Theme (https://communities.geoplatform.gov/ngda-cadastre/). The PAD-US is an ongoing project with several published versions of a spatial database including areas dedicated to the preservation of biological diversity, and other natural (including extraction), recreational, or cultural uses, managed for these purposes through legal or other effective means. The database was originally designed to support biodiversity assessments; however, its scope expanded in recent years to include all public and nonprofit lands and waters. Most are public lands owned in fee (the owner of the property has full and irrevocable ownership of the land); however, long-term easements, leases, agreements, Congressional (e.g. 'Wilderness Area'), Executive (e.g. 'National Monument'), and administrative designations (e.g. 'Area of Critical Environmental Concern') documented in agency management plans are also included. The PAD-US strives to be a complete inventory of public land and other protected areas, compiling “best available” data provided by managing agencies and organizations. The PAD-US geodatabase maps and describes areas using over twenty-five attributes and five feature classes representing the U.S. protected areas network in separate feature classes: Fee (ownership parcels), Designation, Easement, Marine, Proclamation and Other Planning Boundaries. Five additional feature classes include various combinations of the primary layers (for example, Combined_Fee_Easement) to support data management, queries, web mapping services, and analyses. This PAD-US Version 2.1 dataset includes a variety of updates and new data from the previous Version 2.0 dataset (USGS, 2018 https://doi.org/10.5066/P955KPLE ), achieving the primary goal to "Complete the PAD-US Inventory by 2020" (https://www.usgs.gov/core-science-systems/science-analytics-and-synthesis/gap/science/pad-us-vision) by addressing known data gaps with newly available data. The following list summarizes the integration of "best available" spatial data to ensure public lands and other protected areas from all jurisdictions are represented in PAD-US, along with continued improvements and regular maintenance of the federal theme. Completing the PAD-US Inventory: 1) Integration of over 75,000 city parks in all 50 States (and the District of Columbia) from The Trust for Public Land's (TPL) ParkServe data development initiative (https://parkserve.tpl.org/) added nearly 2.7 million acres of protected area and significantly reduced the primary known data gap in previous PAD-US versions (local government lands). 2) First-time integration of the Census American Indian/Alaskan Native Areas (AIA) dataset (https://www2.census.gov/geo/tiger/TIGER2019/AIANNH) representing the boundaries for federally recognized American Indian reservations and off-reservation trust lands across the nation (as of January 1, 2020, as reported by the federally recognized tribal governments through the Census Bureau's Boundary and Annexation Survey) addressed another major PAD-US data gap. 3) Aggregation of nearly 5,000 protected areas owned by local land trusts in 13 states, aggregated by Ducks Unlimited through data calls for easements to update the National Conservation Easement Database (https://www.conservationeasement.us/), increased PAD-US protected areas by over 350,000 acres. Maintaining regular Federal updates: 1) Major update of the Federal estate (fee ownership parcels, easement interest, and management designations), including authoritative data from 8 agencies: Bureau of Land Management (BLM), U.S. Census Bureau (Census), Department of Defense (DOD), U.S. Fish and Wildlife Service (FWS), National Park Service (NPS), Natural Resources Conservation Service (NRCS), U.S. Forest Service (USFS), National Oceanic and Atmospheric Administration (NOAA). The federal theme in PAD-US is developed in close collaboration with the Federal Geographic Data Committee (FGDC) Federal Lands Working Group (FLWG, https://communities.geoplatform.gov/ngda-govunits/federal-lands-workgroup/); 2) Complete National Marine Protected Areas (MPA) update: from the National Oceanic and Atmospheric Administration (NOAA) MPA Inventory, including conservation measure ('GAP Status Code', 'IUCN Category') review by NOAA; Other changes: 1) PAD-US field name change - The "Public Access" field name changed from 'Access' to 'Pub_Access' to avoid unintended scripting errors associated with the script command 'access'. 2) Additional field - The "Feature Class" (FeatClass) field was added to all layers within PAD-US 2.1 (only included in the "Combined" layers of PAD-US 2.0 to describe which feature class data originated from). 3) Categorical GAP Status Code default changes - National Monuments are categorically assigned GAP Status Code = 2 (previously GAP 3), in the absence of other information, to better represent biodiversity protection restrictions associated with the designation. The Bureau of Land Management Areas of Environmental Concern (ACECs) are categorically assigned GAP Status Code = 3 (previously GAP 2) as the areas are administratively protected, not permanent. More information is available upon request. 4) Agency Name (FWS) geodatabase domain description changed to U.S. Fish and Wildlife Service (previously U.S. Fish & Wildlife Service). 5) Select areas in the provisional PAD-US 2.1 Proclamation feature class were removed following a consultation with the data-steward (Census Bureau). Tribal designated statistical areas are purely a geographic area for providing Census statistics with no land base. Most affected areas are relatively small; however, 4,341,120 acres and 37 records were removed in total. Contact Mason Croft (masoncroft@boisestate) for more information about how to identify these records. For more information regarding the PAD-US dataset please visit, https://usgs.gov/gapanalysis/PAD-US/. For more information about data aggregation please review the Online PAD-US Data Manual available at https://www.usgs.gov/core-science-systems/science-analytics-and-synthesis/gap/pad-us-data-manual .

The locations of 1,879 coal mines and facilities, 8 uranium mines, and 1,965 mines and processing plants for 74 types of nonfuel minerals and materials are shown with symbols on both a large multicolored lithologic map and eight smaller maps. With the exception of certain commodities, such as gold, silver, gemstones, and coal, all mines and plants are shown for which production was reported or estimated in 1997. These localities account for most of the fuel and nonfuel minerals and materials produced in the United States in 1997, other than crushed stone, sand and gravel, and common clay. The poster-size map (Map I-2654) is available for purchase from the U.S. Geological Survey Map Distribution, Box 25286, Federal Center, Denver, CO 80225. Internet versions of the map and seven commodity grouping maps that contain data for nonfuel minerals and materials are available. The information presented in the three data documents represents basic data about the 1,965 mines and processing plants shown on the map. Included in each of the three documents is company name, site name, State, county, commodity, and whether the location is a mine, processing plant, or both for each of the locations shown on the map. The data documents contain the basic data arranged by commodity, State, and county. For locations where multiple commodities are produced (for example, a mine that produces both gold and silver), the commodities are listed alphabetically. The value figure shows estimates of the value of nonfuel minerals produced in the United States in 1997. These estimates are presented in descending order by State.

In 2007, the California Ocean Protection Council initiated the California Seafloor Mapping Program (CSMP), designed to create a comprehensive seafloor map of high-resolution bathymetry, marine benthic habitats, and geology within California’s State Waters. The program supports a large number of coastal-zone- and ocean-management issues, including the California Marine Life Protection Act (MLPA) (California Department of Fish and Wildlife, 2008), which requires information about the distribution of ecosystems as part of the design and proposal process for the establishment of Marine Protected Areas. A focus of CSMP is to map California’s State Waters with consistent methods at a consistent scale. The CSMP approach is to create highly detailed seafloor maps through collection, integration, interpretation, and visualization of swath sonar data (the undersea equivalent of satellite remote-sensing data in terrestrial mapping), acoustic backscatter, seafloor video, seafloor photography, high-resolution seismic-reflection profiles, and bottom-sediment sampling data. The map products display seafloor morphology and character, identify potential marine benthic habitats, and illustrate both the surficial seafloor geology and shallow (to about 100 m) subsurface geology. It is emphasized that the more interpretive habitat and geology data rely on the integration of multiple, new high-resolution datasets and that mapping at small scales would not be possible without such data. This approach and CSMP planning is based in part on recommendations of the Marine Mapping Planning Workshop (Kvitek and others, 2006), attended by coastal and marine managers and scientists from around the state. That workshop established geographic priorities for a coastal mapping project and identified the need for coverage of “lands” from the shore strand line (defined as Mean Higher High Water; MHHW) out to the 3-nautical-mile (5.6-km) limit of California’s State Waters. Unfortunately, surveying the zone from MHHW out to 10-m water depth is not consistently possible using ship-based surveying methods, owing to sea state (for example, waves, wind, or currents), kelp coverage, and shallow rock outcrops. Accordingly, some of the data presented in this series commonly do not cover the zone from the shore out to 10-m depth. This data is part of a series of online U.S. Geological Survey (USGS) publications, each of which includes several map sheets, some explanatory text, and a descriptive pamphlet. Each map sheet is published as a PDF file. Geographic information system (GIS) files that contain both ESRI ArcGIS raster grids (for example, bathymetry, seafloor character) and geotiffs (for example, shaded relief) are also included for each publication. For those who do not own the full suite of ESRI GIS and mapping software, the data can be read using ESRI ArcReader, a free viewer that is available at http://www.esri.com/software/arcgis/arcreader/index.html (last accessed September 20, 2013). The California Seafloor Mapping Program is a collaborative venture between numerous different federal and state agencies, academia, and the private sector. CSMP partners include the California Coastal Conservancy, the California Ocean Protection Council, the California Department of Fish and Wildlife, the California Geological Survey, California State University at Monterey Bay’s Seafloor Mapping Lab, Moss Landing Marine Laboratories Center for Habitat Studies, Fugro Pelagos, Pacific Gas and Electric Company, National Oceanic and Atmospheric Administration (NOAA, including National Ocean Service–Office of Coast Surveys, National Marine Sanctuaries, and National Marine Fisheries Service), U.S. Army Corps of Engineers, the Bureau of Ocean Energy Management, the National Park Service, and the U.S. Geological Survey. These web services for the Offshore of Ventura map area includes data layers that are associated to GIS and map sheets available from the USGS CSMP web page at https://walrus.wr.usgs.gov/mapping/csmp/index.html. Each published CSMP map area includes a data catalog of geographic information system (GIS) files; map sheets that contain explanatory text; and an associated descriptive pamphlet. This web service represents the available data layers for this map area. Data was combined from different sonar surveys to generate a comprehensive high-resolution bathymetry and acoustic-backscatter coverage of the map area. These data reveal a range of physiographic including exposed bedrock outcrops, large fields of sand waves, as well as many human impacts on the seafloor. To validate geological and biological interpretations of the sonar data, the U.S. Geological Survey towed a camera sled over specific offshore locations, collecting both video and photographic imagery; these “ground-truth” surveying data are available from the CSMP Video and Photograph Portal at https://doi.org/10.5066/F7J1015K. The “seafloor character” data layer shows classifications of the seafloor on the basis of depth, slope, rugosity (ruggedness), and backscatter intensity and which is further informed by the ground-truth-survey imagery. The “potential habitats” polygons are delineated on the basis of substrate type, geomorphology, seafloor process, or other attributes that may provide a habitat for a specific species or assemblage of organisms. Representative seismic-reflection profile data from the map area is also include and provides information on the subsurface stratigraphy and structure of the map area. The distribution and thickness of young sediment (deposited over the past about 21,000 years, during the most recent sea-level rise) is interpreted on the basis of the seismic-reflection data. The geologic polygons merge onshore geologic mapping (compiled from existing maps by the California Geological Survey) and new offshore geologic mapping that is based on integration of high-resolution bathymetry and backscatter imagery seafloor-sediment and rock samplesdigital camera and video imagery, and high-resolution seismic-reflection profiles. The information provided by the map sheets, pamphlet, and data catalog has a broad range of applications. High-resolution bathymetry, acoustic backscatter, ground-truth-surveying imagery, and habitat mapping all contribute to habitat characterization and ecosystem-based management by providing essential data for delineation of marine protected areas and ecosystem restoration. Many of the maps provide high-resolution baselines that will be critical for monitoring environmental change associated with climate change, coastal development, or other forcings. High-resolution bathymetry is a critical component for modeling coastal flooding caused by storms and tsunamis, as well as inundation associated with longer term sea-level rise. Seismic-reflection and bathymetric data help characterize earthquake and tsunami sources, critical for natural-hazard assessments of coastal zones. Information on sediment distribution and thickness is essential to the understanding of local and regional sediment transport, as well as the development of regional sediment-management plans. In addition, siting of any new offshore infrastructure (for example, pipelines, cables, or renewable-energy facilities) will depend on high-resolution mapping. Finally, this mapping will both stimulate and enable new scientific research and also raise public awareness of, and education about, coastal environments and issues. Web services were created using an ArcGIS service definition file. The ArcGIS REST service and OGC WMS service include all Offshore of Ventura map area data layers. Data layers are symbolized as shown on the associated map sheets.

The National Hydrography Dataset Plus High Resolution (NHDplus High Resolution) maps the lakes, ponds, streams, rivers and other surface waters of the United States. Created by the US Geological Survey, NHDPlus High Resolution provides mean annual flow and velocity estimates for rivers and streams. Additional attributes provide connections between features facilitating complicated analyses.For more information on the NHDPlus High Resolution dataset see the User’s Guide for the National Hydrography Dataset Plus (NHDPlus) High Resolution.Dataset SummaryPhenomenon Mapped: Surface waters and related features of the United States and associated territoriesGeographic Extent: The Contiguous United States, Hawaii, portions of Alaska, Puerto Rico, Guam, US Virgin Islands, Northern Marianas Islands, and American SamoaProjection: Web Mercator Auxiliary Sphere Visible Scale: Visible at all scales but layer draws best at scales larger than 1:1,000,000Source: USGSUpdate Frequency: AnnualPublication Date: July 2022This layer was symbolized in the ArcGIS Map Viewer and while the features will draw in the Classic Map Viewer the advanced symbology will not. Prior to publication, the network and non-network flowline feature classes were combined into a single flowline layer. Similarly, the Area and Waterbody feature classes were merged under a single schema.Attribute fields were added to the flowline and waterbody layers to simplify symbology and enhance the layer's pop-ups. Fields added include Pop-up Title, Pop-up Subtitle, Esri Symbology (waterbodies only), and Feature Code Description. All other attributes are from the original dataset. No data values -9999 and -9998 were converted to Null values.What can you do with this layer?Feature layers work throughout the ArcGIS system. Generally your work flow with feature layers will begin in ArcGIS Online or ArcGIS Pro. Below are just a few of the things you can do with a feature service in Online and Pro.ArcGIS OnlineAdd this layer to a map in the map viewer. The layer or a map containing it can be used in an application. Change the layer’s transparency and set its visibility rangeOpen the layer’s attribute table and make selections. Selections made in the map or table are reflected in the other. Center on selection allows you to zoom to features selected in the map or table and show selected records allows you to view the selected records in the table.Apply filters. For example you can set a filter to show larger streams and rivers using the mean annual flow attribute or the stream order attribute.Change the layer’s style and symbologyAdd labels and set their propertiesCustomize the pop-upUse as an input to the ArcGIS Online analysis tools. This layer works well as a reference layer with the trace downstream and watershed tools. The buffer tool can be used to draw protective boundaries around streams and the extract data tool can be used to create copies of portions of the data.ArcGIS ProAdd this layer to a 2d or 3d map.Use as an input to geoprocessing. For example, copy features allows you to select then export portions of the data to a new feature class.Change the symbology and the attribute field used to symbolize the dataOpen table and make interactive selections with the mapModify the pop-upsApply Definition Queries to create sub-sets of the layerThis layer is part of the ArcGIS Living Atlas of the World that provides an easy way to explore the landscape layers and many other beautiful and authoritative maps on hundreds of topics.Questions?Please leave a comment below if you have a question about this layer, and we will get back to you as soon as possible.

Aquatic environmental DNA (eDNA) sampling is the collection of DNA released by a target species into streams, rivers, ponds, lakes, and wetlands. Detection of stream fish with eDNA can be remarkably sensitive—100% detection efficiency of target species has been achieved despite order-of-magnitude changes in stream discharge. The eDNA samples in the eDNAtlas database describe species occurrence locations and were collected by the U.S. Forest Service and numerous agencies that have partnered with the National Genomics Center for Wildlife and Fish Conservation (NGC) throughout the United States. The data were collected for a variety of project-specific purposes that included: species status assessments, trend monitoring at one or many sites, development of predictive species distribution models, detection and tracking of non-native species invasions, and assessments of habitat restoration efforts. The eDNAtlas database consists of two feature classes. The first component (eDNAtlas_West_AGOL_ResultsOnly) is a database of georeferenced species occurrence locations based on eDNA field sampling results, which are downloadable by species through a dynamic ArcGIS Online (AGOL) mapping tool. The earliest eDNA samples in the database were collected in 2015 but new samples and results are added annually to the database, which houses thousands of species occurrence records. The second component (eDNAtlas_West_SampleGridAndResults) is a systematically-spaced 1-kilometer grid of potential sample points in streams and rivers throughout the western United States. Future versions will include the eastern United States as well. The points in the sampling grid are arrayed along the medium-resolution National Hydrography Dataset Version 2 (NHDPlusV2) and can be used to develop custom eDNA sampling strategies for many purposes. Each sample point has a unique identity code that enables efficient integration of processed eDNA sample results with the species occurrence database. The eDNAtlas is accessed via an interactive ArcGIS Online (AGOL) map that allows users to view and download sample site information and lab results of species occurrence for the U.S. The results are primarily based on samples analyzed at the National Genomics Center for Wildlife and Fish Conservation (NGC) and associated with geospatial attributes created by the Boise Spatial Streams Group (BSSG). The AGOL map displays results for all species sampled within an 8-digit USGS hydrologic unit or series of units. The map initially opens to the project extent, but allows users to zoom to areas of interest. Symbols indicate whether a field sample has been collected and processed at a specific location, and if the latter, whether the target species was present. Each flowing-water site is assigned a unique identification code in the database to ensure that it can be tracked and matched to geospatial habitat descriptors or other attributes for subsequent analyses and reports. Because no comparable database has been built for standing water, results for those sites lack this additional information but still provide data on the sample and species detected. Resources in this dataset:Resource Title: The Aquatic eDNAtlas Project: Lab Results Map - USFS RMRS. File Name: Web Page, url: https://usfs.maps.arcgis.com/apps/webappviewer/index.html?id=b496812d1a8847038687ff1328c481fa The eDNAtlas is accessed via an interactive ArcGIS Online (AGOL) map that allows users to view and download sample site information and lab results of species occurrence for the U.S. The results are primarily based on samples analyzed at the National Genomics Center for Wildlife and Fish Conservation (NGC) and associated with geospatial attributes created by the Boise Spatial Streams Group (BSSG). The AGOL map displays results for all species sampled within an 8-digit USGS hydrologic unit or series of units. The map initially opens to the project extent, but allows users to zoom to areas of interest. Symbols indicate whether a field sample has been collected and processed at a specific location, and if the latter, whether the target species was present. Each flowing-water site is assigned a unique identification code in the database to ensure that it can be tracked and matched to geospatial habitat descriptors or other attributes for subsequent analyses and reports. Because no comparable database has been built for standing water, results for those sites lack this additional information but still provide data on the sample and species detected. For details on using the map see the Aquatic eDNAtlas Project: Lab Results ArcGIS Online Map Guide.

Access National Hydrography ProductsThe National Hydrography Dataset (NHD) is a feature-based database that interconnects and uniquely identifies the stream segments or reaches that make up the nation's surface water drainage system. NHD data was originally developed at 1:100,000-scale and exists at that scale for the whole country. This high-resolution NHD, generally developed at 1:24,000/1:12,000 scale, adds detail to the original 1:100,000-scale NHD. (Data for Alaska, Puerto Rico and the Virgin Islands was developed at high-resolution, not 1:100,000 scale.) Local resolution NHD is being developed where partners and data exist. The NHD contains reach codes for networked features, flow direction, names, and centerline representations for areal water bodies. Reaches are also defined on waterbodies and the approximate shorelines of the Great Lakes, the Atlantic and Pacific Oceans and the Gulf of Mexico. The NHD also incorporates the National Spatial Data Infrastructure framework criteria established by the Federal Geographic Data Committee.The NHD is a national framework for assigning reach addresses to water-related entities, such as industrial discharges, drinking water supplies, fish habitat areas, wild and scenic rivers. Reach addresses establish the locations of these entities relative to one another within the NHD surface water drainage network, much like addresses on streets. Once linked to the NHD by their reach addresses, the upstream/downstream relationships of these water-related entities--and any associated information about them--can be analyzed using software tools ranging from spreadsheets to geographic information systems (GIS). GIS can also be used to combine NHD-based network analysis with other data layers, such as soils, land use and population, to help understand and display their respective effects upon one another. Furthermore, because the NHD provides a nationally consistent framework for addressing and analysis, water-related information linked to reach addresses by one organization (national, state, local) can be shared with other organizations and easily integrated into many different types of applications to the benefit of all.Statements of attribute accuracy are based on accuracy statements made for U.S. Geological Survey Digital Line Graph (DLG) data, which is estimated to be 98.5 percent. One or more of the following methods were used to test attribute accuracy: manual comparison of the source with hardcopy plots; symbolized display of the DLG on an interactive computer graphic system; selected attributes that could not be visually verified on plots or on screen were interactively queried and verified on screen. In addition, software validated feature types and characteristics against a master set of types and characteristics, checked that combinations of types and characteristics were valid, and that types and characteristics were valid for the delineation of the feature. Feature types, characteristics, and other attributes conform to the Standards for National Hydrography Dataset (USGS, 1999) as of the date they were loaded into the database. All names were validated against a current extract from the Geographic Names Information System (GNIS). The entry and identifier for the names match those in the GNIS. The association of each name to reaches has been interactively checked, however, operator error could in some cases apply a name to a wrong reach.Points, nodes, lines, and areas conform to topological rules. Lines intersect only at nodes, and all nodes anchor the ends of lines. Lines do not overshoot or undershoot other lines where they are supposed to meet. There are no duplicate lines. Lines bound areas and lines identify the areas to the left and right of the lines. Gaps and overlaps among areas do not exist. All areas close.The completeness of the data reflects the content of the sources, which most often are the published USGS topographic quadrangle and/or the USDA Forest Service Primary Base Series (PBS) map. The USGS topographic quadrangle is usually supplemented by Digital Orthophoto Quadrangles (DOQs). Features found on the ground may have been eliminated or generalized on the source map because of scale and legibility constraints. In general, streams longer than one mile (approximately 1.6 kilometers) were collected. Most streams that flow from a lake were collected regardless of their length. Only definite channels were collected so not all swamp/marsh features have stream/rivers delineated through them. Lake/ponds having an area greater than 6 acres were collected. Note, however, that these general rules were applied unevenly among maps during compilation. Reach codes are defined on all features of type stream/river, canal/ditch, artificial path, coastline, and connector. Waterbody reach codes are defined on all lake/pond and most reservoir features. Names were applied from the GNIS database. Detailed capture conditions are provided for every feature type in the Standards for National Hydrography Dataset available online through https://prd-wret.s3-us-west-2.amazonaws.com/assets/palladium/production/atoms/files/NHD%201999%20Draft%20Standards%20-%20Capture%20conditions.PDF.Statements of horizontal positional accuracy are based on accuracy statements made for U.S. Geological Survey topographic quadrangle maps. These maps were compiled to meet National Map Accuracy Standards. For horizontal accuracy, this standard is met if at least 90 percent of points tested are within 0.02 inch (at map scale) of the true position. Additional offsets to positions may have been introduced where feature density is high to improve the legibility of map symbols. In addition, the digitizing of maps is estimated to contain a horizontal positional error of less than or equal to 0.003 inch standard error (at map scale) in the two component directions relative to the source maps. Visual comparison between the map graphic (including digital scans of the graphic) and plots or digital displays of points, lines, and areas, is used as control to assess the positional accuracy of digital data. Digital map elements along the adjoining edges of data sets are aligned if they are within a 0.02 inch tolerance (at map scale). Features with like dimensionality (for example, features that all are delineated with lines), with or without like characteristics, that are within the tolerance are aligned by moving the features equally to a common point. Features outside the tolerance are not moved; instead, a feature of type connector is added to join the features.Statements of vertical positional accuracy for elevation of water surfaces are based on accuracy statements made for U.S. Geological Survey topographic quadrangle maps. These maps were compiled to meet National Map Accuracy Standards. For vertical accuracy, this standard is met if at least 90 percent of well-defined points tested are within one-half contour interval of the correct value. Elevations of water surface printed on the published map meet this standard; the contour intervals of the maps vary. These elevations were transcribed into the digital data; the accuracy of this transcription was checked by visual comparison between the data and the map.

This collection of the 3D Elevation Program (3DEP) is at 1/3 arc-second (approximately 10 m) resolution. The 3DEP data holdings serve as the elevation layer of The National Map, and provide foundational elevation information for earth science studies and mapping applications in the United States. Scientists and resource managers use 3DEP data for hydrologic modeling, resource monitoring, mapping and visualization, and many other applications. The elevations in this DEM represent the topographic bare-earth surface. The seamless 1/3 arc-second DEM layers are derived from diverse source data that are processed to a common coordinate system and unit of vertical measure. These data are distributed in geographic coordinates in units of decimal degrees, and in conformance with the North American Datum of 1983 (NAD 83). All elevation values are in meters and, over the continental United States, are referenced to the North American Vertical Datum of 1988 (NAVD88). The vertical reference will vary in other areas. The seamless 1/3 arc-second DEM layer provides coverage of the conterminous United States, Hawaii, Puerto Rico, other territorial islands, and in limited areas of Alaska. These seamless DEMs were referred to as the National Elevation Dataset (NED) from about 2000 through 2015 at which time they became the seamless DEM layers under the 3DEP program and the NED name and system were retired. All 3DEP products are public domain.

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description: Shapefile Format This data set is a result of compiling differing source materials of various vintages. Source material examples used to create and maintain dataset include: BLM 100k Surface Map Publications, Master Title Plats, Public Land Survey GIS Data (cadnsdi v.2.0), Field Office GIS Data, Compiled 24k USGS Maps, and Land Records. Ongoing updates are made.; abstract: Shapefile Format This data set is a result of compiling differing source materials of various vintages. Source material examples used to create and maintain dataset include: BLM 100k Surface Map Publications, Master Title Plats, Public Land Survey GIS Data (cadnsdi v.2.0), Field Office GIS Data, Compiled 24k USGS Maps, and Land Records. Ongoing updates are made.

The USGS Protected Areas Database of the United States (PAD-US) is the nation's inventory of protected areas, including public open space and voluntarily provided, private protected areas, identified as an A-16 National Geospatial Data Asset in the Cadastral Theme (http://www.fgdc.gov/ngda-reports/NGDA_Datasets.html). PAD-US is an ongoing project with several published versions of a spatial database of areas dedicated to the preservation of biological diversity, and other natural, recreational or cultural uses, managed for these purposes through legal or other effective means. The geodatabase maps and describes public open space and other protected areas. Most areas are public lands owned in fee; however, long-term easements, leases, and agreements or administrative designations documented in agency management plans may be included. The PAD-US database strives to be a complete “best available” inventory of protected areas (lands and waters) including data provided by managing agencies and organizations. The dataset is built in collaboration with several partners and data providers (http://gapanalysis.usgs.gov/padus/stewards/). See Supplemental Information Section of this metadata record for more information on partnerships and links to major partner organizations. As this dataset is a compilation of many data sets; data completeness, accuracy, and scale may vary. Federal and state data are generally complete, while local government and private protected area coverage is about 50% complete, and depends on data management capacity in the state. For completeness estimates by state: http://www.protectedlands.net/partners. As the federal and state data are reasonably complete; focus is shifting to completing the inventory of local gov and voluntarily provided, private protected areas. The PAD-US geodatabase contains over twenty-five attributes and four feature classes to support data management, queries, web mapping services and analyses: Marine Protected Areas (MPA), Fee, Easements and Combined. The data contained in the MPA Feature class are provided directly by the National Oceanic and Atmospheric Administration (NOAA) Marine Protected Areas Center (MPA, http://marineprotectedareas.noaa.gov ) tracking the National Marine Protected Areas System. The Easements feature class contains data provided directly from the National Conservation Easement Database (NCED, http://conservationeasement.us ) The MPA and Easement feature classes contain some attributes unique to the sole source databases tracking them (e.g. Easement Holder Name from NCED, Protection Level from NOAA MPA Inventory). The "Combined" feature class integrates all fee, easement and MPA features as the best available national inventory of protected areas in the standard PAD-US framework. In addition to geographic boundaries, PAD-US describes the protection mechanism category (e.g. fee, easement, designation, other), owner and managing agency, designation type, unit name, area, public access and state name in a suite of standardized fields. An informative set of references (i.e. Aggregator Source, GIS Source, GIS Source Date) and "local" or source data fields provide a transparent link between standardized PAD-US fields and information from authoritative data sources. The areas in PAD-US are also assigned conservation measures that assess management intent to permanently protect biological diversity: the nationally relevant "GAP Status Code" and global "IUCN Category" standard. A wealth of attributes facilitates a wide variety of data analyses and creates a context for data to be used at local, regional, state, national and international scales. More information about specific updates and changes to this PAD-US version can be found in the Data Quality Information section of this metadata record as well as on the PAD-US website, http://gapanalysis.usgs.gov/padus/data/history/.) Due to the completeness and complexity of these data, it is highly recommended to review the Supplemental Information Section of the metadata record as well as the Data Use Constraints, to better understand data partnerships as well as see tips and ideas of appropriate uses of the data and how to parse out the data that you are looking for. For more information regarding the PAD-US dataset please visit, http://gapanalysis.usgs.gov/padus/. To find more data resources as well as view example analysis performed using PAD-US data visit, http://gapanalysis.usgs.gov/padus/resources/. The PAD-US dataset and data standard are compiled and maintained by the USGS Gap Analysis Program, http://gapanalysis.usgs.gov/ . For more information about data standards and how the data are aggregated please review the “Standards and Methods Manual for PAD-US,” http://gapanalysis.usgs.gov/padus/data/standards/ .

Since the early 1980's the EROS Alaska Field Office (AFO) has been involved in the acquisition, classification, and analysis of digital land cover data over the State of Alaska, and to a limited extent, northwestern Canada and Wrangle Island, Russia. The digital data currently covers approximately 77% of the land and water within the boundaries of the State of Alaska. These data are currently being made available via the AFO web site to land managers and researchers who may be interested in land cover conditions over various portions of Alaska. The land cover maps as a result of digital analysis of Landsat multispectral scanner, Landsat thematic mapper, and SPOT multispectral scanner satellite data. Some data however, are missing from the database due to data degradation on storage media or loss of data tapes, although a limited number of hard copy map products may be in existence, for example, U.S. Forest Service land cover data for southeast Alaska. The land cover data are stored online in a series of directories and are available via the web. Each directory name is indicative of the area for which the land cover data exists. Some directories connote a U.S. Geological Survey 1:250,000 quadrangle (for example, anchorage_int), while others indicate a particular project area (for example, anwr represents Arctic National Wildlife Refuge) or the agency responsible for producing the data. For example, nowitna.fws indicates that the data were produced for the U.S. Fish and Wildlife Service. Directories with an '_int' suffix denote that the data correspond to the Interim Landcover Mapping project. Each directory contains five files with the following extensions: .bil, .blw, .hdr, .prj, and .stx. As a group, one or more of the files can be read by most image analysis and GIS software packages. The .bil file contains the binary raster land cover data and the others are ASCII files. The .bil file does not contain any header or footer records, and can be easily imported into image processing software by using the information contained in the .blw and .hdr files. The .blw file provides pixel size information as well as the upper left corner coordinate. The .hdr contains number of rows and columns of the data set, as well as band format (band interleave). The .prj file gives projection information, and the .stx file gives information on minimum/maximum/ mean values of the data. Projection parameters for the data sets are either in Universal Transverse Projection (UTM) or Alaska Albers Equal Area Conic.

description: The United States Geological Survey (USGS), in collaboration with other state and federal agencies, industry, and academia, is conducting a National Geochemical Survey (NGS) to produce a database of geochemical information for the United States based primarily on stream sediments, analyzed using a single set of methods. This data set will comprise a national-scale geochemical coverage of the US, and will enable construction of geochemical maps, refine estimates of baseline chemical element concentrations in the sampled media, and provide context for a wide variety of geological and environmental studies. The goal of the NGS is to analyze at least one stream-sediment sample within every 289 km2 area across the US, using a consistent set of analytical methods, substituting soil samples where necessary. The survey incorporates geochemical data from a variety of sources, including existing analyses in USGS databases, reanalyses of samples in USGS archives, and analyses of recently collected samples. Currently, the NGS data covers ~71% of the land area of the US, and includes samples from all 50 states. The Iowa Geological Survey (IGS) of the Iowa Department of Natural Resources (IDNR) entered into an agreement with the USGS in September of 2002 whereby the IGS would design a database for field parameters and collect two soil sample sets. One set for the USGS to process and analyze, and one set to reposit. Field parameters included ambient site conditions, GPS location, elevation, landscape position, vegetation type, NRCS soil type, sample depth, and soil horizon, texture, color and moisture. Digital photographs were taken of the site and samples at each location. The samples were sieved to -100 mesh, then analyzed for 40 elements using inductively coupled plasma-atomic emission spectrometry/acid dissolution (ICP40), and 6 elements using atomic absorption spectrometry (AA). Arsenic (As) and gold (Au) were analyzed for using both methods. Analyses were performed by the USGS or an approved laboratory, using standard methods and an U.S.E.P.A. approved quality assurance/quality control plan. To maximize statistical reliability, sample collection in Iowa was based on a 17 km x 17 km grid, displayed on USGS 1:250,000 quad maps. Each grid or cell was identified by quad name and cell column and row position, and divided into four 72 km2 quadrants, and one was selected at random for sampling. The IGS selected specific sampling sites within the selected quadrants. To separate leached horizons from those accumulating CO3, one shallow (0-8 inches) and one deep (12-24 inches) sample were collected from 463 regular and 72 analysis of variance (AOV) sites from May through August of 2003 and shipped to the USGS in August. Randomly selected AOV sites were sampled to provide a data set for statistical analysis to test the adequacy of the samples to measure differences of sediment chemistry between cells, within cells, within sites, and between chemical analyses. "AOV1" was collected within the designated quadrant of the cell, then one of the three other quadrants of the cell were selected at random for "AOV2" and "AOV3" which were collected about 10 feet apart, preferably within the same soil type. The field data were described on data collection sheets and later transferred to the IGS network through an entry routine on a daily to weekly basis. The DBASE entry routine and database were developed and maintained by IGS personnel, then after the analyses were performed, the data were joined with the soil sample analyses by USGS personnel. The joined database can be accessed at the IGS website at http://www.igsb.uiowa.edu, and for a detailed description of the NGS, visit the USGS website at http://tin.er.usgs.gov/geochem/doc/home.htm; abstract: The United States Geological Survey (USGS), in collaboration with other state and federal agencies, industry, and academia, is conducting a National Geochemical Survey (NGS) to produce a database of geochemical information for the United States based primarily on stream sediments, analyzed using a single set of methods. This data set will comprise a national-scale geochemical coverage of the US, and will enable construction of geochemical maps, refine estimates of baseline chemical element concentrations in the sampled media, and provide context for a wide variety of geological and environmental studies. The goal of the NGS is to analyze at least one stream-sediment sample within every 289 km2 area across the US, using a consistent set of analytical methods, substituting soil samples where necessary. The survey incorporates geochemical data from a variety of sources, including existing analyses in USGS databases, reanalyses of samples in USGS archives, and analyses of recently collected samples. Currently, the NGS data covers ~71% of the land area of the US, and includes samples from all 50 states. The Iowa Geological Survey (IGS) of the Iowa Department of Natural Resources (IDNR) entered into an agreement with the USGS in September of 2002 whereby the IGS would design a database for field parameters and collect two soil sample sets. One set for the USGS to process and analyze, and one set to reposit. Field parameters included ambient site conditions, GPS location, elevation, landscape position, vegetation type, NRCS soil type, sample depth, and soil horizon, texture, color and moisture. Digital photographs were taken of the site and samples at each location. The samples were sieved to -100 mesh, then analyzed for 40 elements using inductively coupled plasma-atomic emission spectrometry/acid dissolution (ICP40), and 6 elements using atomic absorption spectrometry (AA). Arsenic (As) and gold (Au) were analyzed for using both methods. Analyses were performed by the USGS or an approved laboratory, using standard methods and an U.S.E.P.A. approved quality assurance/quality control plan. To maximize statistical reliability, sample collection in Iowa was based on a 17 km x 17 km grid, displayed on USGS 1:250,000 quad maps. Each grid or cell was identified by quad name and cell column and row position, and divided into four 72 km2 quadrants, and one was selected at random for sampling. The IGS selected specific sampling sites within the selected quadrants. To separate leached horizons from those accumulating CO3, one shallow (0-8 inches) and one deep (12-24 inches) sample were collected from 463 regular and 72 analysis of variance (AOV) sites from May through August of 2003 and shipped to the USGS in August. Randomly selected AOV sites were sampled to provide a data set for statistical analysis to test the adequacy of the samples to measure differences of sediment chemistry between cells, within cells, within sites, and between chemical analyses. "AOV1" was collected within the designated quadrant of the cell, then one of the three other quadrants of the cell were selected at random for "AOV2" and "AOV3" which were collected about 10 feet apart, preferably within the same soil type. The field data were described on data collection sheets and later transferred to the IGS network through an entry routine on a daily to weekly basis. The DBASE entry routine and database were developed and maintained by IGS personnel, then after the analyses were performed, the data were joined with the soil sample analyses by USGS personnel. The joined database can be accessed at the IGS website at http://www.igsb.uiowa.edu, and for a detailed description of the NGS, visit the USGS website at http://tin.er.usgs.gov/geochem/doc/home.htm

Access National Hydrography ProductsThe National Hydrography Dataset (NHD) is a feature-based database that interconnects and uniquely identifies the stream segments or reaches that make up the nation's surface water drainage system. NHD data was originally developed at 1:100,000-scale and exists at that scale for the whole country. This high-resolution NHD, generally developed at 1:24,000/1:12,000 scale, adds detail to the original 1:100,000-scale NHD. (Data for Alaska, Puerto Rico and the Virgin Islands was developed at high-resolution, not 1:100,000 scale.) Local resolution NHD is being developed where partners and data exist. The NHD contains reach codes for networked features, flow direction, names, and centerline representations for areal water bodies. Reaches are also defined on waterbodies and the approximate shorelines of the Great Lakes, the Atlantic and Pacific Oceans and the Gulf of Mexico. The NHD also incorporates the National Spatial Data Infrastructure framework criteria established by the Federal Geographic Data Committee.The NHD is a national framework for assigning reach addresses to water-related entities, such as industrial discharges, drinking water supplies, fish habitat areas, wild and scenic rivers. Reach addresses establish the locations of these entities relative to one another within the NHD surface water drainage network, much like addresses on streets. Once linked to the NHD by their reach addresses, the upstream/downstream relationships of these water-related entities--and any associated information about them--can be analyzed using software tools ranging from spreadsheets to geographic information systems (GIS). GIS can also be used to combine NHD-based network analysis with other data layers, such as soils, land use and population, to help understand and display their respective effects upon one another. Furthermore, because the NHD provides a nationally consistent framework for addressing and analysis, water-related information linked to reach addresses by one organization (national, state, local) can be shared with other organizations and easily integrated into many different types of applications to the benefit of all.Statements of attribute accuracy are based on accuracy statements made for U.S. Geological Survey Digital Line Graph (DLG) data, which is estimated to be 98.5 percent. One or more of the following methods were used to test attribute accuracy: manual comparison of the source with hardcopy plots; symbolized display of the DLG on an interactive computer graphic system; selected attributes that could not be visually verified on plots or on screen were interactively queried and verified on screen. In addition, software validated feature types and characteristics against a master set of types and characteristics, checked that combinations of types and characteristics were valid, and that types and characteristics were valid for the delineation of the feature. Feature types, characteristics, and other attributes conform to the Standards for National Hydrography Dataset (USGS, 1999) as of the date they were loaded into the database. All names were validated against a current extract from the Geographic Names Information System (GNIS). The entry and identifier for the names match those in the GNIS. The association of each name to reaches has been interactively checked, however, operator error could in some cases apply a name to a wrong reach.Points, nodes, lines, and areas conform to topological rules. Lines intersect only at nodes, and all nodes anchor the ends of lines. Lines do not overshoot or undershoot other lines where they are supposed to meet. There are no duplicate lines. Lines bound areas and lines identify the areas to the left and right of the lines. Gaps and overlaps among areas do not exist. All areas close.The completeness of the data reflects the content of the sources, which most often are the published USGS topographic quadrangle and/or the USDA Forest Service Primary Base Series (PBS) map. The USGS topographic quadrangle is usually supplemented by Digital Orthophoto Quadrangles (DOQs). Features found on the ground may have been eliminated or generalized on the source map because of scale and legibility constraints. In general, streams longer than one mile (approximately 1.6 kilometers) were collected. Most streams that flow from a lake were collected regardless of their length. Only definite channels were collected so not all swamp/marsh features have stream/rivers delineated through them. Lake/ponds having an area greater than 6 acres were collected. Note, however, that these general rules were applied unevenly among maps during compilation. Reach codes are defined on all features of type stream/river, canal/ditch, artificial path, coastline, and connector. Waterbody reach codes are defined on all lake/pond and most reservoir features. Names were applied from the GNIS database. Detailed capture conditions are provided for every feature type in the Standards for National Hydrography Dataset available online through https://prd-wret.s3-us-west-2.amazonaws.com/assets/palladium/production/atoms/files/NHD%201999%20Draft%20Standards%20-%20Capture%20conditions.PDF.Statements of horizontal positional accuracy are based on accuracy statements made for U.S. Geological Survey topographic quadrangle maps. These maps were compiled to meet National Map Accuracy Standards. For horizontal accuracy, this standard is met if at least 90 percent of points tested are within 0.02 inch (at map scale) of the true position. Additional offsets to positions may have been introduced where feature density is high to improve the legibility of map symbols. In addition, the digitizing of maps is estimated to contain a horizontal positional error of less than or equal to 0.003 inch standard error (at map scale) in the two component directions relative to the source maps. Visual comparison between the map graphic (including digital scans of the graphic) and plots or digital displays of points, lines, and areas, is used as control to assess the positional accuracy of digital data. Digital map elements along the adjoining edges of data sets are aligned if they are within a 0.02 inch tolerance (at map scale). Features with like dimensionality (for example, features that all are delineated with lines), with or without like characteristics, that are within the tolerance are aligned by moving the features equally to a common point. Features outside the tolerance are not moved; instead, a feature of type connector is added to join the features.Statements of vertical positional accuracy for elevation of water surfaces are based on accuracy statements made for U.S. Geological Survey topographic quadrangle maps. These maps were compiled to meet National Map Accuracy Standards. For vertical accuracy, this standard is met if at least 90 percent of well-defined points tested are within one-half contour interval of the correct value. Elevations of water surface printed on the published map meet this standard; the contour intervals of the maps vary. These elevations were transcribed into the digital data; the accuracy of this transcription was checked by visual comparison between the data and the map.

Index map page boundaries of the Mat-Su Borough Tax Map Page Index. The entire Borough is divided into a series of "base maps" and "index" or "grid maps". Base maps are given names that represent the geographical area represented (similar to USGS quad mapping) and index maps are numbered sequentially within the base map. The result is a base map with a two-character name (for example: ("WA" for Wasilla) and numbered index maps (usually numbered "1" thru "16"). The Mat-Su Borough tax map set is published using these pages.

The USGS Protected Areas Database of the United States (PAD-US) is the nation's inventory of protected areas, including public land and voluntarily provided private protected areas, identified as an A-16 National Geospatial Data Asset in the Cadastre Theme ( https://communities.geoplatform.gov/ngda-cadastre/ ). The PAD-US is an ongoing project with several published versions of a spatial database including areas dedicated to the preservation of biological diversity, and other natural (including extraction), recreational, or cultural uses, managed for these purposes through legal or other effective means. The database was originally designed to support biodiversity assessments; however, its scope expanded in recent years to include all open space public and nonprofit lands and waters. Most are public lands owned in fee (the owner of the property has full and irrevocable ownership of the land); however, permanent and long-term easements, leases, agreements, Congressional (e.g. 'Wilderness Area'), Executive (e.g. 'National Monument'), and administrative designations (e.g. 'Area of Critical Environmental Concern') documented in agency management plans are also included. The PAD-US strives to be a complete inventory of U.S. public land and other protected areas, compiling “best available” data provided by managing agencies and organizations. The PAD-US geodatabase maps and describes areas using thirty-six attributes and five separate feature classes representing the U.S. protected areas network: Fee (ownership parcels), Designation, Easement, Marine, Proclamation and Other Planning Boundaries. An additional Combined feature class includes the full PAD-US inventory to support data management, queries, web mapping services, and analyses. The Feature Class (FeatClass) field in the Combined layer allows users to extract data types as needed. A Federal Data Reference file geodatabase lookup table (PADUS3_0Combined_Federal_Data_References) facilitates the extraction of authoritative federal data provided or recommended by managing agencies from the Combined PAD-US inventory. This PAD-US Version 3.0 dataset includes a variety of updates from the previous Version 2.1 dataset (USGS, 2020, https://doi.org/10.5066/P92QM3NT ), achieving goals to: 1) Annually update and improve spatial data representing the federal estate for PAD-US applications; 2) Update state and local lands data as state data-steward and PAD-US Team resources allow; and 3) Automate data translation efforts to increase PAD-US update efficiency. The following list summarizes the integration of "best available" spatial data to ensure public lands and other protected areas from all jurisdictions are represented in the PAD-US (other data were transferred from PAD-US 2.1). Federal updates - The USGS remains committed to updating federal fee owned lands data and major designation changes in annual PAD-US updates, where authoritative data provided directly by managing agencies are available or alternative data sources are recommended. The following is a list of updates or revisions associated with the federal estate: 1) Major update of the Federal estate (fee ownership parcels, easement interest, and management designations where available), including authoritative data from 8 agencies: Bureau of Land Management (BLM), U.S. Census Bureau (Census Bureau), Department of Defense (DOD), U.S. Fish and Wildlife Service (FWS), National Park Service (NPS), Natural Resources Conservation Service (NRCS), U.S. Forest Service (USFS), and National Oceanic and Atmospheric Administration (NOAA). The federal theme in PAD-US is developed in close collaboration with the Federal Geographic Data Committee (FGDC) Federal Lands Working Group (FLWG, https://communities.geoplatform.gov/ngda-govunits/federal-lands-workgroup/ ). 2) Improved the representation (boundaries and attributes) of the National Park Service, U.S. Forest Service, Bureau of Land Management, and U.S. Fish and Wildlife Service lands, in collaboration with agency data-stewards, in response to feedback from the PAD-US Team and stakeholders. 3) Added a Federal Data Reference file geodatabase lookup table (PADUS3_0Combined_Federal_Data_References) to the PAD-US 3.0 geodatabase to facilitate the extraction (by Data Provider, Dataset Name, and/or Aggregator Source) of authoritative data provided directly (or recommended) by federal managing agencies from the full PAD-US inventory. A summary of the number of records (Frequency) and calculated GIS Acres (vs Documented Acres) associated with features provided by each Aggregator Source is included; however, the number of records may vary from source data as the "State Name" standard is applied to national files. The Feature Class (FeatClass) field in the table and geodatabase describe the data type to highlight overlapping features in the full inventory (e.g. Designation features often overlap Fee features) and to assist users in building queries for applications as needed. 4) Scripted the translation of the Department of Defense, Census Bureau, and Natural Resource Conservation Service source data into the PAD-US format to increase update efficiency. 5) Revised conservation measures (GAP Status Code, IUCN Category) to more accurately represent protected and conserved areas. For example, Fish and Wildlife Service (FWS) Waterfowl Production Area Wetland Easements changed from GAP Status Code 2 to 4 as spatial data currently represents the complete parcel (about 10.54 million acres primarily in North Dakota and South Dakota). Only aliquot parts of these parcels are documented under wetland easement (1.64 million acres). These acreages are provided by the U.S. Fish and Wildlife Service and are referenced in the PAD-US geodatabase Easement feature class 'Comments' field. State updates - The USGS is committed to building capacity in the state data-steward network and the PAD-US Team to increase the frequency of state land updates, as resources allow. The USGS supported efforts to significantly increase state inventory completeness with the integration of local parks data in the PAD-US 2.1, and developed a state-to-PAD-US data translation script during PAD-US 3.0 development to pilot in future updates. Additional efforts are in progress to support the technical and organizational strategies needed to increase the frequency of state updates. The PAD-US 3.0 included major updates to the following three states: 1) California - added or updated state, regional, local, and nonprofit lands data from the California Protected Areas Database (CPAD), managed by GreenInfo Network, and integrated conservation and recreation measure changes following review coordinated by the data-steward with state managing agencies. Developed a data translation Python script (see Process Step 2 Source Data Documentation) in collaboration with the data-steward to increase the accuracy and efficiency of future PAD-US updates from CPAD. 2) Virginia - added or updated state, local, and nonprofit protected areas data (and removed legacy data) from the Virginia Conservation Lands Database, provided by the Virginia Department of Conservation and Recreation's Natural Heritage Program, and integrated conservation and recreation measure changes following review by the data-steward. 3) West Virginia - added or updated state, local, and nonprofit protected areas data provided by the West Virginia University, GIS Technical Center. For more information regarding the PAD-US dataset please visit, https://www.usgs.gov/gapanalysis/PAD-US/. For more information about data aggregation please review the PAD-US Data Manual available at https://www.usgs.gov/core-science-systems/science-analytics-and-synthesis/gap/pad-us-data-manual . A version history of PAD-US updates is summarized below (See https://www.usgs.gov/core-science-systems/science-analytics-and-synthesis/gap/pad-us-data-history for more information): 1) First posted - April 2009 (Version 1.0 - available from the PAD-US: Team pad-us@usgs.gov). 2) Revised - May 2010 (Version 1.1 - available from the PAD-US: Team pad-us@usgs.gov). 3) Revised - April 2011 (Version 1.2 - available from the PAD-US: Team pad-us@usgs.gov). 4) Revised - November 2012 (Version 1.3) https://doi.org/10.5066/F79Z92XD 5) Revised - May 2016 (Version 1.4) https://doi.org/10.5066/F7G73BSZ 6) Revised - September 2018 (Version 2.0) https://doi.org/10.5066/P955KPLE 7) Revised - September 2020 (Version 2.1) https://doi.org/10.5066/P92QM3NT 8) Revised - January 2022 (Version 3.0) https://doi.org/10.5066/P9Q9LQ4B Comparing protected area trends between PAD-US versions is not recommended without consultation with USGS as many changes reflect improvements to agency and organization GIS systems, or conservation and recreation measure classification, rather than actual changes in protected area acquisition on the ground.

Ferromanganese crusts in the world's oceans may serve as potential sources of metals, such as cobalt and magnesium, valuable to civilian and military industry; these are metals that the United States would otherwise be dependent on foreign sources. Unlike abyssal ferromanganese nodules, which form in areas of low disturbance and high sediment accumulation, ferromanganese crusts have been found to contain three to five times more cobalt than abyssal ferromanganese nodules and can be found on harder, steeper substrates than abyssal plains, which can be too steep for permanent sediment accumulation. Ferromanganese crusts have also been documented on seamounts and plateaus within the U.S. exclusive economic zone in the Pacific and Atlantic Oceans and are therefore of strategic importance to the United States Government as well as to civilian mining and metallurgical industries. A database containing ferromanganese crust occurrences throughout the world's oceans was assembled from published and unpublished sources to provide data gathering and analytical information for these samples. These data provide the digital formatted locations of the sample locations of the U.S. Geological Survey and Scripps Institution Nodule Data Bank (SNDB) from appendixes A and B. These locations from 1986 and earlier are also represented on the maps of Lane and others (1986). > Lane, C.M., Manheim, F.T., Hathaway, J.C., and Ling, T.H., 1986, Station maps of the world ocean-ferromanganese-rust database: U.S. Geological Survey Miscellaneous Field Studies Map, 1869, http://pubs.usgs.gov/mf/1986/1869/

Analysis of ‘Connecticut Parcels’ provided by Analyst-2 (analyst-2.ai), based on source dataset retrieved from https://catalog.data.gov/dataset/868228bd-9ccc-409d-8348-2c8a9dcc2ca4 on 12 February 2022.

--- Dataset description provided by original source is as follows ---

Connecticut Parcels for Protected Open Space Mapping is a polygon feature-based layer that includes basic parcel-level information for some towns in Connecticut. This parcel layer includes information provided by individual municipalities. These parcel data are incomplete and out of date. The accuracy, currency and completeness of the data reflect the content of the data at the time DEEP acquired the data from the individual municipalities. Attribute information is comprised of values such as town name and map lot block number. These data are not updated by CT DEEP and should only be used as a general reference. Critical decisions involving parcel-level information should be based on more recently acquired information from the respective municipalities. These parcels are not to be considered legal boundaries such as boundaries determined from certain classified survey maps or deed descriptions. Parcel boundaries shown in this layer are based on information from municipalities used for property tax purposes. Largely due to differences in horizontal accuracy among various data layers, do not expect these parcel boundaries to line up exactly with or be properly postioned relative to features shown on other layers available from CT DEEP such as scanned USGS topography quadrangle maps, roads, hydrography, town boundaries, and even orthophotograpy.

The data in the parcel layer was obtained from individual Connecticut municipalities. An effort was made to collect data once from each municipality. The data acquisition date for each set of municipally-supplied parcel data was not recorded and CT DEEP does not keep this information up-to-date. Consequently, these data are out-of-date, incomplete and do not reflect the current state of property ownership in these municipalities. These parcels are not to be considered legal boundaries such as boundaries determined from certain classified survey maps or deed descriptions. Parcel boundaries shown in this layer are based on information from municipalities used for property tax purposes. Parcel boundaries and attribute information have not been updated in this layer since the time the information was originally acquired by CT DEEP. For example, property boundaries are incorrect where subdivisions have occurred. Also, field attribute values are populated only if the information was supplied to CT DEEP. For example, parcels in some towns lack location (street name) information or possibly map lot block values. Therefore, field attributes are inconsistent, may include gaps, and do not represent complete sets of values among all towns. They should not be compared and analyzed across towns. It is emphasized that critical decisions involving parcel-level information be based on more recently obtained information from the respective municipalities. These data are only suitable for general reference purposes. Be cautious when using these data. Many Connecticut municipalities provide access to more up-to-date and more detailed property ownership information on the Internet. This dataset includes parcel information for the following towns: Andover, Ansonia, Ashford, Avon, Beacon Falls, Berlin, Bethany, Bethel, Bethlehem, Bloomfield, Bolton, Branford, Bridgewater, Brookfield, Brooklyn, Canaan, Canterbury, Canton, Chaplin, Cheshire, Chester, Clinton, Colchester, Colebrook, Columbia, Cornwall, Coventry, Cromwell, Danbury, Darien, Deep River, Derby, East Granby, East Haddam, East Hampton, East Hartford, East Lyme, East Windsor, Eastford, Ellington, Enfield, Essex, Farmington, Franklin, Glastonbury, Granby, Greenwich, Griswold, Groton, Guilford, Haddam, Hamden, Hartford, Hebron, Kent, Killingly, Killingworth, Lebanon, Ledyard, Lisbon, Litchfield, Lyme, Madison, Manchester, Mansfield, Marlborough, Meriden, Middlebury, Middlefield, Middletown, Milford, Monroe, Montville, Morri

--- Original source retains full ownership of the source dataset ---

Analysis of ‘Connecticut Parcels’ provided by Analyst-2 (analyst-2.ai), based on source dataset retrieved from https://catalog.data.gov/dataset/a5737d62-0fb8-4079-8f1b-b8a16dac96ef on 12 February 2022.

--- Dataset description provided by original source is as follows ---

Connecticut Parcels for Protected Open Space Mapping is a polygon feature-based layer that includes basic parcel-level information for some towns in Connecticut. This parcel layer includes information provided by individual municipalities. These parcel data are incomplete and out of date. The accuracy, currency and completeness of the data reflect the content of the data at the time DEEP acquired the data from the individual municipalities. Attribute information is comprised of values such as town name and map lot block number. These data are not updated by CT DEEP and should only be used as a general reference. Critical decisions involving parcel-level information should be based on more recently acquired information from the respective municipalities. These parcels are not to be considered legal boundaries such as boundaries determined from certain classified survey maps or deed descriptions. Parcel boundaries shown in this layer are based on information from municipalities used for property tax purposes. Largely due to differences in horizontal accuracy among various data layers, do not expect these parcel boundaries to line up exactly with or be properly postioned relative to features shown on other layers available from CT DEEP such as scanned USGS topography quadrangle maps, roads, hydrography, town boundaries, and even orthophotograpy.

The data in the parcel layer was obtained from individual Connecticut municipalities. An effort was made to collect data once from each municipality. The data acquisition date for each set of municipally-supplied parcel data was not recorded and CT DEEP does not keep this information up-to-date. Consequently, these data are out-of-date, incomplete and do not reflect the current state of property ownership in these municipalities. These parcels are not to be considered legal boundaries such as boundaries determined from certain classified survey maps or deed descriptions. Parcel boundaries shown in this layer are based on information from municipalities used for property tax purposes. Parcel boundaries and attribute information have not been updated in this layer since the time the information was originally acquired by CT DEEP. For example, property boundaries are incorrect where subdivisions have occurred. Also, field attribute values are populated only if the information was supplied to CT DEEP. For example, parcels in some towns lack location (street name) information or possibly map lot block values. Therefore, field attributes are inconsistent, may include gaps, and do not represent complete sets of values among all towns. They should not be compared and analyzed across towns. It is emphasized that critical decisions involving parcel-level information be based on more recently obtained information from the respective municipalities. These data are only suitable for general reference purposes. Be cautious when using these data. Many Connecticut municipalities provide access to more up-to-date and more detailed property ownership information on the Internet. This dataset includes parcel information for the following towns: Andover, Ansonia, Ashford, Avon, Beacon Falls, Berlin, Bethany, Bethel, Bethlehem, Bloomfield, Bolton, Branford, Bridgewater, Brookfield, Brooklyn, Canaan, Canterbury, Canton, Chaplin, Cheshire, Chester, Clinton, Colchester, Colebrook, Columbia, Cornwall, Coventry, Cromwell, Danbury, Darien, Deep River, Derby, East Granby, East Haddam, East Hampton, East Hartford, East Lyme, East Windsor, Eastford, Ellington, Enfield, Essex, Farmington, Franklin, Glastonbury, Granby, Greenwich, Griswold, Groton, Guilford, Haddam, Hamden, Hartford, Hebron, Kent, Killingly, Killingworth, Lebanon, Ledyard, Lisbon, Litchfield, Lyme, Madison, Manchester, Mansfield, Marlborough, Meriden, Middlebury, Middlefield, Middletown, Milford, Monroe, Montville, Morri

--- Original source retains full ownership of the source dataset ---

http://gapanalysis.usgs.gov/padus/data/metadata/ The USGS Protected Areas Database of the United States (PAD-US) is the nation's inventory of protected areas, including public open space and voluntarily provided, private protected areas, identified as an A-16 National Geospatial Data Asset in the Cadastral Theme (http://www.fgdc.gov/ngda-reports/NGDA_Datasets.html). PAD-US is an ongoing project with several published versions of a spatial database of areas dedicated to the preservation of biological diversity, and other natural, recreational or cultural uses, managed for these purposes through legal or other effective means. The geodatabase maps and describes public open space and other protected areas. Most areas are public lands owned in fee; however, long-term easements, leases, and agreements or administrative designations documented in agency management plans may be included. The PAD-US database strives to be a complete “best available” inventory of protected areas (lands and waters) including data provided by managing agencies and organizations. The dataset is built in collaboration with several partners and data providers (http://gapanalysis.usgs.gov/padus/stewards/). See Supplemental Information Section of this metadata record for more information on partnerships and links to major partner organizations. As this dataset is a compilation of many data sets; data completeness, accuracy, and scale may vary. Federal and state data are generally complete, while local government and private protected area coverage is about 50% complete, and depends on data management capacity in the state. For completeness estimates by state: http://www.protectedlands.net/partners. As the federal and state data are reasonably complete; focus is shifting to completing the inventory of local gov and voluntarily provided, private protected areas. The PAD-US geodatabase contains over twenty-five attributes and four feature classes to support data management, queries, web mapping services and analyses: Marine Protected Areas (MPA), Fee, Easements and Combined. The data contained in the MPA Feature class are provided directly by the National Oceanic and Atmospheric Administration (NOAA) Marine Protected Areas Center (MPA, http://marineprotectedareas.noaa.gov ) tracking the National Marine Protected Areas System. The Easements feature class contains data provided directly from the National Conservation Easement Database (NCED, http://conservationeasement.us ) The MPA and Easement feature classes contain some attributes unique to the sole source databases tracking them (e.g. Easement Holder Name from NCED, Protection Level from NOAA MPA Inventory). The "Combined" feature class integrates all fee, easement and MPA features as the best available national inventory of protected areas in the standard PAD-US framework. In addition to geographic boundaries, PAD-US describes the protection mechanism category (e.g. fee, easement, designation, other), owner and managing agency, designation type, unit name, area, public access and state name in a suite of standardized fields. An informative set of references (i.e. Aggregator Source, GIS Source, GIS Source Date) and "local" or source data fields provide a transparent link between standardized PAD-US fields and information from authoritative data sources. The areas in PAD-US are also assigned conservation measures that assess management intent to permanently protect biological diversity: the nationally relevant "GAP Status Code" and global "IUCN Category" standard. A wealth of attributes facilitates a wide variety of data analyses and creates a context for data to be used at local, regional, state, national and international scales. More information about specific updates and changes to this PAD-US version can be found in the Data Quality Information section of this metadata record as well as on the PAD-US website, http://gapanalysis.usgs.gov/padus/data/history/.) Due to the completeness and complexity of these data, it is highly recommended to review the Supplemental Information Section of the metadata record as well as the Data Use Constraints, to better understand data partnerships as well as see tips and ideas of appropriate uses of the data and how to parse out the data that you are looking for. For more information regarding the PAD-US dataset please visit, http://gapanalysis.usgs.gov/padus/. To find more data resources as well as view example analysis performed using PAD-US data visit, http://gapanalysis.usgs.gov/padus/resources/. The PAD-US dataset and data standard are compiled and maintained by the USGS Gap Analysis Program, http://gapanalysis.usgs.gov/ . For more information about data standards and how the data are aggregated please review the “Standards and Methods Manual for PAD-US,” http://gapanalysis.usgs.gov/padus/data/standards/ .