100+ datasets found
  1. n

    Data from: A new digital method of data collection for spatial point pattern...

    • data.niaid.nih.gov
    • search.dataone.org
    • +1more
    zip
    Updated Jul 6, 2021
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    Chao Jiang; Xinting Wang (2021). A new digital method of data collection for spatial point pattern analysis in grassland communities [Dataset]. http://doi.org/10.5061/dryad.brv15dv70
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    zipAvailable download formats
    Dataset updated
    Jul 6, 2021
    Dataset provided by
    Chinese Academy of Agricultural Sciences
    Inner Mongolia University of Technology
    Authors
    Chao Jiang; Xinting Wang
    License

    https://spdx.org/licenses/CC0-1.0.htmlhttps://spdx.org/licenses/CC0-1.0.html

    Description

    A major objective of plant ecology research is to determine the underlying processes responsible for the observed spatial distribution patterns of plant species. Plants can be approximated as points in space for this purpose, and thus, spatial point pattern analysis has become increasingly popular in ecological research. The basic piece of data for point pattern analysis is a point location of an ecological object in some study region. Therefore, point pattern analysis can only be performed if data can be collected. However, due to the lack of a convenient sampling method, a few previous studies have used point pattern analysis to examine the spatial patterns of grassland species. This is unfortunate because being able to explore point patterns in grassland systems has widespread implications for population dynamics, community-level patterns and ecological processes. In this study, we develop a new method to measure individual coordinates of species in grassland communities. This method records plant growing positions via digital picture samples that have been sub-blocked within a geographical information system (GIS). Here, we tested out the new method by measuring the individual coordinates of Stipa grandis in grazed and ungrazed S. grandis communities in a temperate steppe ecosystem in China. Furthermore, we analyzed the pattern of S. grandis by using the pair correlation function g(r) with both a homogeneous Poisson process and a heterogeneous Poisson process. Our results showed that individuals of S. grandis were overdispersed according to the homogeneous Poisson process at 0-0.16 m in the ungrazed community, while they were clustered at 0.19 m according to the homogeneous and heterogeneous Poisson processes in the grazed community. These results suggest that competitive interactions dominated the ungrazed community, while facilitative interactions dominated the grazed community. In sum, we successfully executed a new sampling method, using digital photography and a Geographical Information System, to collect experimental data on the spatial point patterns for the populations in this grassland community.

    Methods 1. Data collection using digital photographs and GIS

    A flat 5 m x 5 m sampling block was chosen in a study grassland community and divided with bamboo chopsticks into 100 sub-blocks of 50 cm x 50 cm (Fig. 1). A digital camera was then mounted to a telescoping stake and positioned in the center of each sub-block to photograph vegetation within a 0.25 m2 area. Pictures were taken 1.75 m above the ground at an approximate downward angle of 90° (Fig. 2). Automatic camera settings were used for focus, lighting and shutter speed. After photographing the plot as a whole, photographs were taken of each individual plant in each sub-block. In order to identify each individual plant from the digital images, each plant was uniquely marked before the pictures were taken (Fig. 2 B).

    Digital images were imported into a computer as JPEG files, and the position of each plant in the pictures was determined using GIS. This involved four steps: 1) A reference frame (Fig. 3) was established using R2V software to designate control points, or the four vertexes of each sub-block (Appendix S1), so that all plants in each sub-block were within the same reference frame. The parallax and optical distortion in the raster images was then geometrically corrected based on these selected control points; 2) Maps, or layers in GIS terminology, were set up for each species as PROJECT files (Appendix S2), and all individuals in each sub-block were digitized using R2V software (Appendix S3). For accuracy, the digitization of plant individual locations was performed manually; 3) Each plant species layer was exported from a PROJECT file to a SHAPE file in R2V software (Appendix S4); 4) Finally each species layer was opened in Arc GIS software in the SHAPE file format, and attribute data from each species layer was exported into Arc GIS to obtain the precise coordinates for each species. This last phase involved four steps of its own, from adding the data (Appendix S5), to opening the attribute table (Appendix S6), to adding new x and y coordinate fields (Appendix S7) and to obtaining the x and y coordinates and filling in the new fields (Appendix S8).

    1. Data reliability assessment

    To determine the accuracy of our new method, we measured the individual locations of Leymus chinensis, a perennial rhizome grass, in representative community blocks 5 m x 5 m in size in typical steppe habitat in the Inner Mongolia Autonomous Region of China in July 2010 (Fig. 4 A). As our standard for comparison, we used a ruler to measure the individual coordinates of L. chinensis. We tested for significant differences between (1) the coordinates of L. chinensis, as measured with our new method and with the ruler, and (2) the pair correlation function g of L. chinensis, as measured with our new method and with the ruler (see section 3.2 Data Analysis). If (1) the coordinates of L. chinensis, as measured with our new method and with the ruler, and (2) the pair correlation function g of L. chinensis, as measured with our new method and with the ruler, did not differ significantly, then we could conclude that our new method of measuring the coordinates of L. chinensis was reliable.

    We compared the results using a t-test (Table 1). We found no significant differences in either (1) the coordinates of L. chinensis or (2) the pair correlation function g of L. chinensis. Further, we compared the pattern characteristics of L. chinensis when measured by our new method against the ruler measurements using a null model. We found that the two pattern characteristics of L. chinensis did not differ significantly based on the homogenous Poisson process or complete spatial randomness (Fig. 4 B). Thus, we concluded that the data obtained using our new method was reliable enough to perform point pattern analysis with a null model in grassland communities.

  2. Geospatial data for the Vegetation Mapping Inventory Project of Theodore...

    • catalog.data.gov
    Updated Nov 25, 2025
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    National Park Service (2025). Geospatial data for the Vegetation Mapping Inventory Project of Theodore Roosevelt National Park [Dataset]. https://catalog.data.gov/dataset/geospatial-data-for-the-vegetation-mapping-inventory-project-of-theodore-roosevelt-nationa
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    Dataset updated
    Nov 25, 2025
    Dataset provided by
    National Park Servicehttp://www.nps.gov/
    Description

    The files linked to this reference are the geospatial data created as part of the completion of the baseline vegetation inventory project for the NPS park unit. Current format is ArcGIS file geodatabase but older formats may exist as shapefiles. An ArcInfo (copyright ESRI) GIS database was designed for THRO using the National Park GIS Database Design, Layout, and Procedures created by RSGIG. This was created through Arc Macro Language (AML) scripts that helped automate the transfer process and ensure that all spatial and attribute data was consistent and stored properly. Actual transfer of information from the interpreted aerial photographs to a digital, geo-referenced format involved two techniques, scanning (for the vegetation classes) and on-screen digitizing (for the land-use classes). Transferred information used to create vegetation polygon coverages and linear coverages in ArcInfo were based on quarter-quad borders. Attribute information including vegetation map unit, location, and aerial photo number was subsequently entered for all polygons. In addition, the spatial database has an FGDC-compliant metadata file.

  3. G

    Geospatial Analytics Market Report

    • marketresearchforecast.com
    doc, pdf, ppt
    Updated Jan 10, 2025
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    Market Research Forecast (2025). Geospatial Analytics Market Report [Dataset]. https://www.marketresearchforecast.com/reports/geospatial-analytics-market-1650
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    doc, ppt, pdfAvailable download formats
    Dataset updated
    Jan 10, 2025
    Dataset authored and provided by
    Market Research Forecast
    License

    https://www.marketresearchforecast.com/privacy-policyhttps://www.marketresearchforecast.com/privacy-policy

    Time period covered
    2025 - 2033
    Area covered
    Global
    Variables measured
    Market Size
    Description

    The Geospatial Analytics Marketsize was valued at USD 79.06 USD billion in 2023 and is projected to reach USD 202.74 USD billion by 2032, exhibiting a CAGR of 14.4 % during the forecast period. Recent developments include: February 2024: Placer.ai and Esri, a Geographic Information System (GIS) technology provider, partnered to empower customers with enhanced analytics capabilities, integrating consumer behavior analysis. Additionally, the agreement will foster collaborations to unlock further features by synergizing our respective product offerings., December 2023: CKS and Esri India Technologies Pvt Ltd teamed up to introduce the 'MMGEIS' program, focusing on students from 8th grade to undergraduates, to position India as a global leader in geospatial technology through skill development and innovation., December 2023: In collaboration with Bayanat, the UAE Space Agency revealed the initiation of the operational phase of the Geospatial Analytics Platform during its participation in organizing the Space at COP28 initiatives., November 2023: USAID unveiled its inaugural Geospatial Strategy, designed to harness geospatial data and technology for more targeted international program delivery. The strategy foresees a future where geographic methods enhance the effectiveness of USAID's efforts by pinpointing development needs, monitoring program implementation, and evaluating outcomes based on location., May 2023: TomTom International BV, a geolocation technology specialist, expanded its partnership with Alteryx, Inc. Through this partnership, Alteryx will use TomTom’s Maps APIs and location data to integrate spatial data into Alteryx’s products and location insights packages, such as Alteryx Designer., May 2023: Oracle Corporation announced the launch of Oracle Spatial Studio 23.1, available in the Oracle Cloud Infrastructure (OCI) marketplace and for on-premises deployment. Users can browse, explore, and analyze geographic data stored in and managed by Oracle using a no-code mapping tool., May 2023: CAPE Analytics, a property intelligence company, announced an enhanced insurance offering by leveraging Google geospatial data. Google’s geospatial data can help CAPE create appropriate solutions for insurance carriers., February 2023: HERE Global B.V. announced a collaboration with Cognizant, an information technology, services, and consulting company, to offer digital customer experience using location data. In this partnership, Cognizant will utilize the HERE location platform’s real-time traffic data, weather, and road attribute data to develop spatial intelligent solutions for its customers., July 2022: Athenium Analytics, a climate risk analytics company, launched a comprehensive tornado data set on the Esri ArcGIS Marketplace. This offering, which included the last 25 years of tornado insights from Athenium Analytics, would extend its Bronze partner relationship with Esri. . Key drivers for this market are: Advancements in Technologies to Fuel Market Growth. Potential restraints include: Lack of Standardization Coupled with Shortage of Skilled Workforce to Limit Market Growth. Notable trends are: Rise of Web-based GIS Platforms Will Transform Market.

  4. BSEE Data Center - Geographic Mapping Data in Digital Format

    • catalog.data.gov
    Updated Nov 25, 2025
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    Bureau of Safety and Environmental Enforcement (2025). BSEE Data Center - Geographic Mapping Data in Digital Format [Dataset]. https://catalog.data.gov/dataset/bsee-data-center-geographic-mapping-data-in-digital-format
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    Dataset updated
    Nov 25, 2025
    Dataset provided by
    Bureau of Safety and Environmental Enforcementhttp://www.bsee.gov/
    Description

    The geographic data are built from the Technical Information Management System (TIMS). TIMS consists of two separate databases: an attribute database and a spatial database. The attribute information for offshore activities is stored in the TIMS database. The spatial database is a combination of the ARC/INFO and FINDER databases and contains all the coordinates and topology information for geographic features. The attribute and spatial databases are interconnected through the use of common data elements in both databases, thereby creating the spatial datasets. The data in the mapping files are made up of straight-line segments. If an arc existed in the original data, it has been replaced with a series of straight lines that approximate the arc. The Gulf of America OCS Region stores all its mapping data in longitude and latitude format. All coordinates are in NAD 27. Data can be obtained in three types of digital formats: INTERACTIVE MAP: The ArcGIS web maps are an interactive display of geographic information, containing a basemap, a set of data layers (many of which include interactive pop-up windows with information about the data), an extent, navigation tools to pan and zoom, and additional tools for geospatial analysis. SHP: A Shapefile is a digital vector (non-topological) storage format for storing geometric location and associated attribute information. Shapefiles can support point, line, and area features with attributes held in a dBASE format file. GEODATABASE: An ArcGIS geodatabase is a collection of geographic datasets of various types held in a common file system folder, a Microsoft Access database, or a multiuser relational DBMS (such as Oracle, Microsoft SQL Server, PostgreSQL, Informix, or IBM DB2). The geodatabase is the native data structure for ArcGIS and is the primary data format used for editing and data management.

  5. a

    Facility Site Points

    • hub.arcgis.com
    • catalog.data.gov
    • +3more
    Updated Dec 23, 2016
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    Lake County Illinois GIS (2016). Facility Site Points [Dataset]. https://hub.arcgis.com/maps/lakecountyil::facility-site-points
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    Dataset updated
    Dec 23, 2016
    Dataset authored and provided by
    Lake County Illinois GIS
    License

    https://www.arcgis.com/sharing/rest/content/items/89679671cfa64832ac2399a0ef52e414/datahttps://www.arcgis.com/sharing/rest/content/items/89679671cfa64832ac2399a0ef52e414/data

    Area covered
    Description

    Download In State Plane Projection Here. Landmark (Facility Site) point and polygons utilize the Esri Local Government Information model to structure the attribute data. Point features are updated on an as-needed basis. Update Frequency: This dataset is updated on a weekly basis.

  6. Geodatabase for the Baltimore Ecosystem Study Spatial Data

    • search.dataone.org
    • portal.edirepository.org
    Updated Apr 1, 2020
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    Spatial Analysis Lab; Jarlath O'Neal-Dunne; Morgan Grove (2020). Geodatabase for the Baltimore Ecosystem Study Spatial Data [Dataset]. https://search.dataone.org/view/https%3A%2F%2Fpasta.lternet.edu%2Fpackage%2Fmetadata%2Feml%2Fknb-lter-bes%2F3120%2F150
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    Dataset updated
    Apr 1, 2020
    Dataset provided by
    Long Term Ecological Research Networkhttp://www.lternet.edu/
    Authors
    Spatial Analysis Lab; Jarlath O'Neal-Dunne; Morgan Grove
    Time period covered
    Jan 1, 1999 - Jun 1, 2014
    Area covered
    Description

    The establishment of a BES Multi-User Geodatabase (BES-MUG) allows for the storage, management, and distribution of geospatial data associated with the Baltimore Ecosystem Study. At present, BES data is distributed over the internet via the BES website. While having geospatial data available for download is a vast improvement over having the data housed at individual research institutions, it still suffers from some limitations. BES-MUG overcomes these limitations; improving the quality of the geospatial data available to BES researches, thereby leading to more informed decision-making. BES-MUG builds on Environmental Systems Research Institute's (ESRI) ArcGIS and ArcSDE technology. ESRI was selected because its geospatial software offers robust capabilities. ArcGIS is implemented agency-wide within the USDA and is the predominant geospatial software package used by collaborating institutions. Commercially available enterprise database packages (DB2, Oracle, SQL) provide an efficient means to store, manage, and share large datasets. However, standard database capabilities are limited with respect to geographic datasets because they lack the ability to deal with complex spatial relationships. By using ESRI's ArcSDE (Spatial Database Engine) in conjunction with database software, geospatial data can be handled much more effectively through the implementation of the Geodatabase model. Through ArcSDE and the Geodatabase model the database's capabilities are expanded, allowing for multiuser editing, intelligent feature types, and the establishment of rules and relationships. ArcSDE also allows users to connect to the database using ArcGIS software without being burdened by the intricacies of the database itself. For an example of how BES-MUG will help improve the quality and timeless of BES geospatial data consider a census block group layer that is in need of updating. Rather than the researcher downloading the dataset, editing it, and resubmitting to through ORS, access rules will allow the authorized user to edit the dataset over the network. Established rules will ensure that the attribute and topological integrity is maintained, so that key fields are not left blank and that the block group boundaries stay within tract boundaries. Metadata will automatically be updated showing who edited the dataset and when they did in the event any questions arise. Currently, a functioning prototype Multi-User Database has been developed for BES at the University of Vermont Spatial Analysis Lab, using Arc SDE and IBM's DB2 Enterprise Database as a back end architecture. This database, which is currently only accessible to those on the UVM campus network, will shortly be migrated to a Linux server where it will be accessible for database connections over the Internet. Passwords can then be handed out to all interested researchers on the project, who will be able to make a database connection through the Geographic Information Systems software interface on their desktop computer. This database will include a very large number of thematic layers. Those layers are currently divided into biophysical, socio-economic and imagery categories. Biophysical includes data on topography, soils, forest cover, habitat areas, hydrology and toxics. Socio-economics includes political and administrative boundaries, transportation and infrastructure networks, property data, census data, household survey data, parks, protected areas, land use/land cover, zoning, public health and historic land use change. Imagery includes a variety of aerial and satellite imagery. See the readme: http://96.56.36.108/geodatabase_SAL/readme.txt See the file listing: http://96.56.36.108/geodatabase_SAL/diroutput.txt

  7. Geospatial data for the Vegetation Mapping Inventory Project of Wind Cave...

    • catalog.data.gov
    • s.cnmilf.com
    Updated Nov 25, 2025
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    National Park Service (2025). Geospatial data for the Vegetation Mapping Inventory Project of Wind Cave National Park [Dataset]. https://catalog.data.gov/dataset/geospatial-data-for-the-vegetation-mapping-inventory-project-of-wind-cave-national-park
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    Dataset updated
    Nov 25, 2025
    Dataset provided by
    National Park Servicehttp://www.nps.gov/
    Description

    The files linked to this reference are the geospatial data created as part of the completion of the baseline vegetation inventory project for the NPS park unit. Current format is ArcGIS file geodatabase but older formats may exist as shapefiles. An ArcInfo(tm) (ESRI) GIS database was designed for WICA using the National Park GIS Database Design, Layout, and Procedures created by the BOR. This was created through Arc Macro Language (AML) scripts that helped automate the transfer process and ensure that all spatial and attribute data was consistent and stored properly. Actual transfer of information from the interpreted aerial photographs to a digital, geo-referenced format involved two techniques, scanning (for the vegetation classes) and on-screen digitizing (for the land-use classes). Both techniques required the use of 14 digital black-and-white orthophoto quarter quadrangles (DOQQ's) covering the study area. Transferred information was used to create vegetation polygon coverages and ancillary linear coverages in ArcInfo(tm) for each WICA DOQQ. Attribute information including vegetation map unit, location, and aerial photo number was subsequently entered for all polygons.

  8. l

    Intersections

    • visionzero.geohub.lacity.org
    • geohub.lacity.org
    • +4more
    Updated Nov 14, 2015
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    boegis_lahub (2015). Intersections [Dataset]. https://visionzero.geohub.lacity.org/datasets/lahub::intersections/about
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    Dataset updated
    Nov 14, 2015
    Dataset authored and provided by
    boegis_lahub
    Area covered
    Description

    This intersection points feature class represents current intersections in the City of Los Angeles. Few intersection points, named pseudo nodes, are used to split the street centerline at a point that is not a true intersection at the ground level. The Mapping and Land Records Division of the Bureau of Engineering, Department of Public Works provides the most current geographic information of the public right of way. The right of way information is available on NavigateLA, a website hosted by the Bureau of Engineering, Department of Public Works.Intersection layer was created in geographical information systems (GIS) software to display intersection points. Intersection points are placed where street line features join or cross each other and where freeway off- and on-ramp line features join street line features. The intersection points layer is a feature class in the LACityCenterlineData.gdb Geodatabase dataset. The layer consists of spatial data as a point feature class and attribute data for the features. The intersection points relates to the intersection attribute table, which contains data describing the limits of the street segment, by the CL_NODE_ID field. The layer shows the location of the intersection points on map products and web mapping applications, and the Department of Transportation, LADOT, uses the intersection points in their GIS system. The intersection attributes are used in the Intersection search function on BOE's web mapping application NavigateLA. The intersection spatial data and related attribute data are maintained in the Intersection layer using Street Centerline Editing application. The City of Los Angeles Municipal code states, all public right-of-ways (roads, alleys, etc) are streets, thus all of them have intersections. List of Fields:Y: This field captures the georeferenced location along the vertical plane of the point in the data layer that is projected in Stateplane Coordinate System NAD83. For example, Y = in the record of a point, while the X = .CL_NODE_ID: This field value is entered as new point features are added to the edit layer, during Street Centerline application editing process. The values are assigned automatically and consecutively by the ArcGIS software first to the street centerline spatial data layer, then the intersections point spatial data layer, and then the intersections point attribute data during the creation of new intersection points. Each intersection identification number is a unique value. The value relates to the street centerline layer attributes, to the INT_ID_FROM and INT_ID_TO fields. One or more street centerline features intersect the intersection point feature. For example, if a street centerline segment ends at a cul-de-sac, then the point feature intersects only one street centerline segment.X: This field captures the georeferenced location along the horizontal plane of the point in the data layer that is projected in Stateplane Coordinate System NAD83. For example, X = in the record of a point, while the Y = .ASSETID: User-defined feature autonumber.USER_ID: The name of the user carrying out the edits.SHAPE: Feature geometry.LST_MODF_DT: Last modification date of the polygon feature.LAT: This field captures the Latitude in deciaml degrees units of the point in the data layer that is projected in Geographic Coordinate System GCS_North_American_1983.OBJECTID: Internal feature number.CRTN_DT: Creation date of the polygon feature.TYPE: This field captures a value for intersection point features that are psuedo nodes or outside of the City. A pseudo node, or point, does not signify a true intersection of two or more different street centerline features. The point is there to split the line feature into two segments. A pseudo node may be needed if for example, the Bureau of Street Services (BSS) has assigned different SECT_ID values for those segments. Values: • S - Feature is a pseudo node and not a true intersection. • null - Feature is an intersection point. • O - Intersection point is outside of the City of LA boundary.LON: This field captures the Longitude in deciaml degrees units of the point in the data layer that is projected in Geographic Coordinate System GCS_North_American_1983.

  9. Geospatial data for the Vegetation Mapping Inventory Project of Assateague...

    • catalog.data.gov
    • data.amerigeoss.org
    Updated Nov 25, 2025
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    National Park Service (2025). Geospatial data for the Vegetation Mapping Inventory Project of Assateague Island National Seashore [Dataset]. https://catalog.data.gov/dataset/geospatial-data-for-the-vegetation-mapping-inventory-project-of-assateague-island-national
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    Dataset updated
    Nov 25, 2025
    Dataset provided by
    National Park Servicehttp://www.nps.gov/
    Area covered
    Assateague Island
    Description

    The files linked to this reference are the geospatial data created as part of the completion of the baseline vegetation inventory project for the NPS park unit. Current format is ArcGIS file geodatabase but older formats may exist as shapefiles. Converting delineations to a digital format involved four main procedures: a) preparation of manuscript maps b) input of the spatial data: c) populating of the attribute tables, and d) conversion to GIS. Each step included many quality control steps. Maps were prepared by pin-registering a clean sheet of mylar to each photo and transferring delineations to the new overlay in ink. Each manuscript map was edgematched to the adjoining sheet. Each photo was numbered, and each polygon on the photo was numbered in sequence. An attribute table was created containing a field each for the photo number, polygon sequence number, land use code, layer number, stature type, height, density, and floristic composition attributes.

  10. a

    Facility Site Polygons

    • hub.arcgis.com
    • s.cnmilf.com
    • +6more
    Updated Dec 23, 2016
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    Lake County Illinois GIS (2016). Facility Site Polygons [Dataset]. https://hub.arcgis.com/datasets/lakecountyil::facility-site-polygons
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    Dataset updated
    Dec 23, 2016
    Dataset authored and provided by
    Lake County Illinois GIS
    License

    https://www.arcgis.com/sharing/rest/content/items/89679671cfa64832ac2399a0ef52e414/datahttps://www.arcgis.com/sharing/rest/content/items/89679671cfa64832ac2399a0ef52e414/data

    Area covered
    Description

    Download In State Plane Projection Here. Landmark (Facility Site) point and polygons utilize the Esri Local Government Information model to structure the attribute data. Polygon features are mapped by tax parcel with updates occurring on a weekly basis as either parcel or feature changes are detected.

    Update Frequency: This dataset is updated on a weekly basis.

  11. g

    Data from: Watershed Boundary Dataset

    • gimi9.com
    • data.ct.gov
    • +3more
    Updated Feb 1, 2001
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    (2001). Watershed Boundary Dataset [Dataset]. https://gimi9.com/dataset/data-gov_watershed-boundary-dataset/
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    Dataset updated
    Feb 1, 2001
    License

    CC0 1.0 Universal Public Domain Dedicationhttps://creativecommons.org/publicdomain/zero/1.0/
    License information was derived automatically

    Description

    This data set is a digital hydrologic unit boundary layer that is at the Subwatershed (12-digit) level. The original data set was developed by delineating the boundary lines on base USGS 1:24000 scale topographic quadrangle, and digitizing the delineated lines. Digital Raster Graphics (DRG) images were used for edits to the data layer.This data set consists of geo-referenced digital map data and attribute data. The spatial data are in a statewide coverage format and include complete coverage of the entire state of Connecticut, and small parts of surrounding states. The hydrologic unit ID code attached to each delineated polygon is linked to the attribute data.

  12. D

    King County Assessor Residential Unit Types and Sizes

    • data.seattle.gov
    • catalog.data.gov
    • +2more
    csv, xlsx, xml
    Updated Nov 11, 2025
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    (2025). King County Assessor Residential Unit Types and Sizes [Dataset]. https://data.seattle.gov/dataset/King-County-Assessor-Residential-Unit-Types-and-Si/ri3y-zeyp
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    csv, xml, xlsxAvailable download formats
    Dataset updated
    Nov 11, 2025
    Area covered
    King County
    Description
    PLEASE NOTE: If choosing the Download option of "Spreadsheet" the field PIN is reformatted to a number - you will need to format it as a 10 character text string with leading zeros to join this data with data from King County.

    King County Assessor (KCA) data has been compiled to create a dataset of unit types and sizes by tax parcel identification number (PIN). City of Seattle spatial overlay data has been assigned through geographic overlay processes. This data is updated periodically and is used to support the analytical and reporting functions of the City of Seattle long-range and policy planning office.

    See the data in action in this dashboard.

    The table includes attribute data from the King County Assessor tables that characterize the use, number of units, number of bedrooms and building square footage (net) for all buildings that indicate a residential use. Due to the way KCA reports the data, some records are for all units within individual buildings (residential and commercial building records), while other records are for the combination of unit type and number of bedrooms (apartment and condominium records) on a particular property (called complex in the table). Therefore there may be many records for any given PIN.

    Some unit counts and type assignments have been imputed based on other data to allow characterization of the complete data set. Other fields have been added to aid in classification for planning purposes such as the complex category. Every effort is made to characterize the data accurately.

    Spatial overlay data for various City of Seattle reporting geographies are assigned as "majority rules" by land area in cases where multiple geographies span a single tax parcel.

    KCA tax parcels are created by King County for property tax assessment and collection and may not match development sites as defined by the City of Seattle (single buildings may span multiple tax parcels), may be stacked on top of each other to represent undivided interest and vertical parcels, or may be made up of several sites that are not contiguous.

    Attributes include parcel centroid locations in latitude/longitude and Washington State Plane X,Y. To get polygon representation of the data please see King County's open data page for parcels and join this table through the PIN field. Please be aware that the King County Assessor site address is not a postal address and may not match other address sources for the same property such as postal, utility billing, and permitting.

    See the detailed data dictionaries for the King County Assessor tables for more information.
  13. d

    Data from: Digital data for the Salinas Valley Geological Framework,...

    • catalog.data.gov
    • data.usgs.gov
    • +1more
    Updated Oct 29, 2025
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    U.S. Geological Survey (2025). Digital data for the Salinas Valley Geological Framework, California [Dataset]. https://catalog.data.gov/dataset/digital-data-for-the-salinas-valley-geological-framework-california
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    Dataset updated
    Oct 29, 2025
    Dataset provided by
    United States Geological Surveyhttp://www.usgs.gov/
    Area covered
    Salinas, Salinas Valley, California
    Description

    This digital dataset was created as part of a U.S. Geological Survey study, done in cooperation with the Monterey County Water Resource Agency, to conduct a hydrologic resource assessment and develop an integrated numerical hydrologic model of the hydrologic system of Salinas Valley, CA. As part of this larger study, the USGS developed this digital dataset of geologic data and three-dimensional hydrogeologic framework models, referred to here as the Salinas Valley Geological Framework (SVGF), that define the elevation, thickness, extent, and lithology-based texture variations of nine hydrogeologic units in Salinas Valley, CA. The digital dataset includes a geospatial database that contains two main elements as GIS feature datasets: (1) input data to the 3D framework and textural models, within a feature dataset called “ModelInput”; and (2) interpolated elevation, thicknesses, and textural variability of the hydrogeologic units stored as arrays of polygonal cells, within a feature dataset called “ModelGrids”. The model input data in this data release include stratigraphic and lithologic information from water, monitoring, and oil and gas wells, as well as data from selected published cross sections, point data derived from geologic maps and geophysical data, and data sampled from parts of previous framework models. Input surface and subsurface data have been reduced to points that define the elevation of the top of each hydrogeologic units at x,y locations; these point data, stored in a GIS feature class named “ModelInputData”, serve as digital input to the framework models. The location of wells used a sources of subsurface stratigraphic and lithologic information are stored within the GIS feature class “ModelInputData”, but are also provided as separate point feature classes in the geospatial database. Faults that offset hydrogeologic units are provided as a separate line feature class. Borehole data are also released as a set of tables, each of which may be joined or related to well location through a unique well identifier present in each table. Tables are in Excel and ascii comma-separated value (CSV) format and include separate but related tables for well location, stratigraphic information of the depths to top and base of hydrogeologic units intercepted downhole, downhole lithologic information reported at 10-foot intervals, and information on how lithologic descriptors were classed as sediment texture. Two types of geologic frameworks were constructed and released within a GIS feature dataset called “ModelGrids”: a hydrostratigraphic framework where the elevation, thickness, and spatial extent of the nine hydrogeologic units were defined based on interpolation of the input data, and (2) a textural model for each hydrogeologic unit based on interpolation of classed downhole lithologic data. Each framework is stored as an array of polygonal cells: essentially a “flattened”, two-dimensional representation of a digital 3D geologic framework. The elevation and thickness of the hydrogeologic units are contained within a single polygon feature class SVGF_3DHFM, which contains a mesh of polygons that represent model cells that have multiple attributes including XY location, elevation and thickness of each hydrogeologic unit. Textural information for each hydrogeologic unit are stored in a second array of polygonal cells called SVGF_TextureModel. The spatial data are accompanied by non-spatial tables that describe the sources of geologic information, a glossary of terms, a description of model units that describes the nine hydrogeologic units modeled in this study. A data dictionary defines the structure of the dataset, defines all fields in all spatial data attributer tables and all columns in all nonspatial tables, and duplicates the Entity and Attribute information contained in the metadata file. Spatial data are also presented as shapefiles. Downhole data from boreholes are released as a set of tables related by a unique well identifier, tables are in Excel and ascii comma-separated value (CSV) format.

  14. Geospatial data for the Vegetation Mapping Inventory Project of Chaco...

    • catalog.data.gov
    Updated Nov 25, 2025
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    National Park Service (2025). Geospatial data for the Vegetation Mapping Inventory Project of Chaco Culture National Historical Park [Dataset]. https://catalog.data.gov/dataset/geospatial-data-for-the-vegetation-mapping-inventory-project-of-chaco-culture-national-his
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    Dataset updated
    Nov 25, 2025
    Dataset provided by
    National Park Servicehttp://www.nps.gov/
    Description

    The files linked to this reference are the geospatial data created as part of the completion of the baseline vegetation inventory project for the NPS park unit. Current format is ArcGIS file geodatabase but older formats may exist as shapefiles. The transfer process for the CHCU vegetation mapping project involved taking the interpreted line work and rendering it into a comprehensive digital network of attributed polygons. To accomplish this, we created an ArcInfo© GIS database using in-house protocols. The protocols consist of a shell (master file) of Arc Macro Language (AML) scripts and menus (nearly 100 files) that automate the transfer process, thus insuring that all spatial and attribute data are consistent and stored properly. The actual transfer of information from the interpreted orthophotos to a digital, geo-referenced format involved scanning, rasterizing, vectorizing, cleaning, building topology, and labeling each polygon.

  15. d

    Ministry of Land, Infrastructure and Transport_GIS Building General...

    • data.go.kr
    json+xml
    Updated Jul 1, 2025
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    (2025). Ministry of Land, Infrastructure and Transport_GIS Building General Collection Information (WMS/WFS) [Dataset]. https://www.data.go.kr/en/data/15123552/openapi.do
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    json+xmlAvailable download formats
    Dataset updated
    Jul 1, 2025
    License

    https://data.go.kr/ugs/selectPortalPolicyView.dohttps://data.go.kr/ugs/selectPortalPolicyView.do

    Description

    This is a GIS building information service that provides a feature set including map images, shapes, and attribute values generated from geographic data of information that combines GIS building integrated information from real estate comprehensive information and building register attribute information from the building administration system (Seumteo). When called with RestAPI, data is returned in json/xml format.

  16. n

    Evaluation of Sub-Sea Physical Environmental Data for the Beaufort OCS and...

    • catalog.northslopescience.org
    Updated Feb 23, 2016
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    (2016). Evaluation of Sub-Sea Physical Environmental Data for the Beaufort OCS and Incorporation in to a Geographic Information (GIS) Database OCS Study MMS 2002-017 [Dataset]. https://catalog.northslopescience.org/dataset/990
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    Dataset updated
    Feb 23, 2016
    Description

    This study, published on CD-ROM, presents a comprehensive database that synthesizes spatial and attribute information collected during shallow geological and geophysical surveys of the Federal Outer Continental Shelf in the Beaufort Sea, Alaska. The surveys were conducted on the Beaufort Sea Continental Shelf between Barrow, Alaska in the west and the Canadian border to the east (Figure 1). The Geohazards Database includes raw and interpretated data from the collection of high-resolution seismic data in the Beaufort Sea. The included survey data are from twenty eight (28) site-clearance surveys for proposed exploratory wells, four (4) years of repetitive pipeline-route surveys for the Northstar Development area; two (2) years repetitive pipeline-route surveys for the proposed Liberty Development, and three (3) surveys of the Boulder Patch. In addition, the database includes boring and grab-sample data from the surveys, regional bathymetry, and historical earthquake data. The database provides spatial and attribute information for surface features such as the Boulder Patch, strudel scour, ice gouges, and bottom relief (bathymetry); spatial data on subsurface features such as shallow faults, shallow gas, and channels; and spatial data on other features such as shotpoint surveys, shallow borings, and earthquakes.

  17. Corners Surveyed by the Bureau of Land Management within Alaska

    • data.doi.gov
    Updated Mar 17, 2021
    + more versions
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    Bureau of Land Management (2021). Corners Surveyed by the Bureau of Land Management within Alaska [Dataset]. https://data.doi.gov/dataset/corners-surveyed-by-the-bureau-of-land-management-within-alaska
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    Dataset updated
    Mar 17, 2021
    Dataset provided by
    Bureau of Land Managementhttp://www.blm.gov/
    Area covered
    Alaska
    Description

    This dataset is a spatial representation of the Public Land Survey System (PLSS) in Alaska, generated from land survey records. The data represents a seamless spatial portrayal of land parcels, their legal descriptions, corner positioning and markings, and survey measurements. This data is intended for mapping purposes only and is not a substitute or replacement for the legal land survey records or other legal documents. Measurement and attribute data are collected from survey records using data entry screens into a relational database. The database design is based upon the FGDC Cadastral Content Data Standard. Corner positions are derived by geodetic calculations using measurement records. Closure and edgematching are applied to produce a seamless dataset. The resultant features do not preserve the original geometry of survey measurements, but the record measurements are reported as attributes. Additional boundary data are derived by spatial capture, protraction and GIS processing. The spatial features are stored and managed within the relational database, with active links to the represented measurement and attribute data.

  18. BLM National Surface Management Agency: Area Polygons, Withdrawal Area...

    • data.wu.ac.at
    esri rest
    Updated Apr 21, 2015
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    Federal Geographic Data Committee (2015). BLM National Surface Management Agency: Area Polygons, Withdrawal Area Polygons, and Special Public Purpose Withdrawal Area Polygons [Dataset]. https://data.wu.ac.at/odso/data_gov/OTU3ZGVmZDMtZjdiOS00ZWVlLWE0MzMtZTYwYjU3OTQ2ZjIx
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    esri restAvailable download formats
    Dataset updated
    Apr 21, 2015
    Dataset provided by
    Federal Geographic Data Committee
    License

    U.S. Government Workshttps://www.usa.gov/government-works
    License information was derived automatically

    Area covered
    6f545f21326b09bf1ff5c840541e9d55dc79157e
    Description

    The SMA implementation is comprised of one feature dataset, with several polygon feature classes, rather than a single feature class. SurfaceManagementAgency: The Surface Management Agency (SMA) Geographic Information System (GIS) dataset depicts Federal land for the United States and classifies this land by its active Federal surface managing agency. The SMA feature class covers the continental United States, Alaska, Hawaii, Puerto Rico, Guam, American Samoa and the Virgin Islands. A Federal SMA agency refers to a Federal agency with administrative jurisdiction over the surface of Federal lands. Jurisdiction over the land is defined when the land is either: Withdrawn by some administrative or legislative action, or Acquired or Exchanged by a Federal Agency. This layer is a dynamic assembly of spatial data layers maintained at various federal and local government offices. The GIS data contained in this dataset represents the polygon features that show the boundaries for Surface Management Agency and the surface extent of each Federal agencyâ s surface administrative jurisdiction. SMA data depicts current withdrawn areas for a particular agency and (when appropriate) includes land that was acquired or exchanged and is located outside of a withdrawal area for that agency. The SMA data do not illustrate land status ownership pattern boundaries or contain land ownership attribute details. SMA_Withdrawals: The Surface Management Agency (SMA) Withdrawals Geographic Information System (GIS) dataset includes all of the known withdrawals which transfer surface jurisdictional responsibilities to federal agencies. The SMA Withdrawls feature class covers the continental United States, Alaska, Hawaii, Puerto Rico, Guam, American Samoa and the Virgin Islands. A Federal SMA Withdrawal is defined by formal actions that set aside, withhold, or reserve Federal land by statute or administrative order for public purposes. A withdrawal creates a title encumbrance on the land. Withdrawals must accomplish one or more of the following: A. Transfer total or partial jurisdiction of Federal land between Federal agencies. B. Close (segregate) Federal land to operation of all or some of the public land laws and/or mineral laws. C. Dedicate Federal land to a specific public purpose. There are four major categories of formal withdrawals: (1) Administrative, (2) Presidential Proclamations, (3) Congressional, and (4) Federal Power Act (FPA) or Federal Energy Regulatory Commission (FERC) Withdrawals. These SMA Withdrawals will include the present total extent of withdrawn areas rather than all of the individual withdrawal actions that created them over time. These data do not illustrate land status ownership pattern boundaries or contain land ownership attribute details. SPP_WithdrawalAreas: The Special Public Purpose (SPP) Withdrawals Geographic Information System (GIS) dataset includes all of the known SPP Withdrawal Areas, which limit use or access to Federal lands (e.g. Wilderness, National Monument). The Special Public Purpose Withdrawal Areas feature class covers the continental United States, Alaska, Hawaii, Puerto Rico, Guam, American Samoa and the Virgin Islands. A Federal SPP Withdrawal Area is defined by formal actions that set aside, withhold, or reserve Federal land by statute or administrative order for public purposes. A withdrawal creates a title encumbrance on the land. Withdrawals must accomplish one or more of the following: A. Transfer total or partial jurisdiction of Federal land between Federal agencies. B. Close (segregate) Federal land to operation of all or some of the public land laws and/or mineral laws. C. Dedicate Federal land to a specific public purpose. There are four major categories of formal withdrawals: (1) Administrative, (2) Presidential Proclamations, (3) Congressional, and (4) Federal Power Act (FPA) or Federal Energy Regulatory Commission (FERC) Withdrawals. These SPP Withdrawals include the present total extent of withdrawn areas rather than all of the individual withdrawal actions that created them over time. These data do not illustrate land status ownership pattern boundaries or contain land ownership attribute details.

  19. c

    Tax Parcel Fabric Data

    • s.cnmilf.com
    • datasets.ai
    • +2more
    Updated Mar 22, 2025
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    Lake County Illinois GIS (2025). Tax Parcel Fabric Data [Dataset]. https://s.cnmilf.com/user74170196/https/catalog.data.gov/dataset/tax-parcel-fabric-data-460e8
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    Dataset updated
    Mar 22, 2025
    Dataset provided by
    Lake County Illinois GIS
    Description

    Download In State Plane Projection Here The 2024 Parcel Fabric Data is a copy of the Lake County Chief Assessor's Office spatial dataset, consisting of separate layers which represent the boundaries for Tax Parcels, Lots, Units, Subs, Condos, Rights of Way, and Encumbrance parcels, along with points, lines, and PLSS townships for reference, which have all been captured for the 2024 Tax Year.This data is spatial in nature and does not include extensive fields of attributes to which each layer may be associated. This data is provided for use to individuals or entities with an understanding of Esri's ArcGIS Pro (specifically the Parcel Fabric), and those with access to ArcGIS Pro, which is necessary to view or manipulate the data.Casual users can find the standalone Tax Parcel Boundary Data here and Parcel Attribute Data here. Update Frequency: This dataset is updated on a yearly basis.

  20. l

    Streets (Centerline)

    • geohub.lacity.org
    • visionzero.geohub.lacity.org
    • +4more
    Updated Nov 14, 2015
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    lahub_admin (2015). Streets (Centerline) [Dataset]. https://geohub.lacity.org/datasets/streets-centerline/api
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    Dataset updated
    Nov 14, 2015
    Dataset authored and provided by
    lahub_admin
    Area covered
    Description

    This street centerline lines feature class represents current right of way in the City of Los Angeles. It shows the official street names and is related to the official street name data. The Mapping and Land Records Division of the Bureau of Engineering, Department of Public Works provides the most current geographic information of the public right of way. The right of way information is available on NavigateLA, a website hosted by the Bureau of Engineering, Department of Public Works. Street Centerline layer was created in geographical information systems (GIS) software to display Dedicated street centerlines. The street centerline layer is a feature class in the LACityCenterlineData.gdb Geodatabase dataset. The layer consists of spatial data as a line feature class and attribute data for the features. City of LA District Offices use Street Centerline layer to determine dedication and street improvement requirements. Engineering street standards are followed to dedicate the street for development. The Bureau of Street Services tracks the location of existing streets, who need to maintain that road. Additional information was added to Street Centerline layer. Address range attributes were added make layer useful for geocoding. Section ID values from Bureau of Street Services were added to make layer useful for pavement management. Department of City Planning added street designation attributes taken from Community Plan maps. The street centerline relates to the Official Street Name table named EASIS, Engineering Automated Street Inventory System, which contains data describing the limits of the street segment. A street centerline segment should only be added to the Street Centerline layer if documentation exists, such as a Deed or a Plan approved by the City Council. Paper streets are street lines shown on a recorded plan but have not yet come into existence on the ground. These street centerline segments are in the Street Centerline layer because there is documentation such as a Deed or a Plan for the construction of that street. Previously, some street line features were added although documentation did not exist. Currently, a Deed, Tract, or a Plan must exist in order to add street line features. Many street line features were edited by viewing the Thomas Bros Map's Transportation layer, TRNL_037 coverage, back when the street centerline coverage was created. When TBM and BOE street centerline layers were compared visually, TBM's layer contained many valid streets that BOE layer did not contain. In addition to TBM streets, Planning Department requested adding street line segments they use for reference. Further, the street centerline layer features are split where the lines intersect. The intersection point is created and maintained in the Intersection layer. The intersection attributes are used in the Intersection search function on NavigateLA on BOE's web mapping application NavigateLA. The City of Los Angeles Municipal code states, all public right-of-ways (roads, alleys, etc) are streets, thus all of them have intersections. Note that there are named alleys in the BOE Street Centerline layer. Since the line features for named alleys are stored in the Street Centerline layer, there are no line features for named alleys in those areas that are geographically coincident in the Alley layer. For a named alley , the corresponding record contains the street designation field value of ST_DESIG = 20, and there is a name stored in the STNAME and STSFX fields.List of Fields:SHAPE: Feature geometry.OBJECTID: Internal feature number.STNAME_A: Street name Alias.ST_SUBTYPE: Street subtype.SV_STATUS: Status of street in service, whether the street is an accessible roadway. Values: • Y - Yes • N - NoTDIR: Street direction. Values: • S - South • N - North • E - East • W - WestADLF: From address range, left side.ZIP_R: Zip code right.ADRT: To address range, right side.INT_ID_TO: Street intersection identification number at the line segment's end node. The value relates to the intersection layer attribute table, to the CL_NODE_ID field. The values are assigned automatically and consecutively by the ArcGIS software first to the street centerline data layer and then the intersections data layer, during the creation of new intersection points. Each intersection identification number is a unique value.SECT_ID: Section ID used by the Bureau of Street Services. Values: • none - No Section ID value • private - Private street • closed - Street is closed from service • temp - Temporary • propose - Proposed construction of a street • walk - Street line is a walk or walkway • known as - • numeric value - A 7 digit numeric value for street resurfacing • outside - Street line segment is outside the City of Los Angeles boundary • pierce - Street segment type • alley - Named alleySTSFX_A: Street suffix Alias.SFXDIR: Street direction suffix Values: • N - North • E - East • W - West • S - SouthCRTN_DT: Creation date of the polygon feature.STNAME: Street name.ZIP_L: Zip code left.STSFX: Street suffix. Values: • BLVD - BoulevardADLT: To address range, left side.ID: Unique line segment identifierMAPSHEET: The alpha-numeric mapsheet number, which refers to a valid B-map or A-map number on the Cadastral tract index map. Values: • B, A, -5A - Any of these alpha-numeric combinations are used, whereas the underlined spaces are the numbers.STNUM: Street identification number. This field relates to the Official Street Name table named EASIS, to the corresponding STR_ID field.ASSETID: User-defined feature autonumber.TEMP: This attribute is no longer used. This attribute was used to enter 'R' for reference arc line segments that were added to the spatial data, in coverage format. Reference lines were temporary and not part of the final data layer. After editing the permanent line segments, the user would delete temporary lines given by this attribute.LST_MODF_DT: Last modification date of the polygon feature.REMARKS: This attribute is a combination of remarks about the street centerline. Values include a general remark, the Council File number, which refers the street status, or whether a private street is a private driveway. The Council File number can be researched on the City Clerk's website http://cityclerk.lacity.org/lacityclerkconnect/INT_ID_FROM: Street intersection identification number at the line segment's start node. The value relates to the intersection layer attribute table, to the CL_NODE_ID field. The values are assigned automatically and consecutively by the ArcGIS software first to the street centerline data layer and then the intersections data layer, during the creation of new intersection points. Each intersection identification number is a unique value.ADRF: From address range, right side.

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Chao Jiang; Xinting Wang (2021). A new digital method of data collection for spatial point pattern analysis in grassland communities [Dataset]. http://doi.org/10.5061/dryad.brv15dv70

Data from: A new digital method of data collection for spatial point pattern analysis in grassland communities

Related Article
Explore at:
zipAvailable download formats
Dataset updated
Jul 6, 2021
Dataset provided by
Chinese Academy of Agricultural Sciences
Inner Mongolia University of Technology
Authors
Chao Jiang; Xinting Wang
License

https://spdx.org/licenses/CC0-1.0.htmlhttps://spdx.org/licenses/CC0-1.0.html

Description

A major objective of plant ecology research is to determine the underlying processes responsible for the observed spatial distribution patterns of plant species. Plants can be approximated as points in space for this purpose, and thus, spatial point pattern analysis has become increasingly popular in ecological research. The basic piece of data for point pattern analysis is a point location of an ecological object in some study region. Therefore, point pattern analysis can only be performed if data can be collected. However, due to the lack of a convenient sampling method, a few previous studies have used point pattern analysis to examine the spatial patterns of grassland species. This is unfortunate because being able to explore point patterns in grassland systems has widespread implications for population dynamics, community-level patterns and ecological processes. In this study, we develop a new method to measure individual coordinates of species in grassland communities. This method records plant growing positions via digital picture samples that have been sub-blocked within a geographical information system (GIS). Here, we tested out the new method by measuring the individual coordinates of Stipa grandis in grazed and ungrazed S. grandis communities in a temperate steppe ecosystem in China. Furthermore, we analyzed the pattern of S. grandis by using the pair correlation function g(r) with both a homogeneous Poisson process and a heterogeneous Poisson process. Our results showed that individuals of S. grandis were overdispersed according to the homogeneous Poisson process at 0-0.16 m in the ungrazed community, while they were clustered at 0.19 m according to the homogeneous and heterogeneous Poisson processes in the grazed community. These results suggest that competitive interactions dominated the ungrazed community, while facilitative interactions dominated the grazed community. In sum, we successfully executed a new sampling method, using digital photography and a Geographical Information System, to collect experimental data on the spatial point patterns for the populations in this grassland community.

Methods 1. Data collection using digital photographs and GIS

A flat 5 m x 5 m sampling block was chosen in a study grassland community and divided with bamboo chopsticks into 100 sub-blocks of 50 cm x 50 cm (Fig. 1). A digital camera was then mounted to a telescoping stake and positioned in the center of each sub-block to photograph vegetation within a 0.25 m2 area. Pictures were taken 1.75 m above the ground at an approximate downward angle of 90° (Fig. 2). Automatic camera settings were used for focus, lighting and shutter speed. After photographing the plot as a whole, photographs were taken of each individual plant in each sub-block. In order to identify each individual plant from the digital images, each plant was uniquely marked before the pictures were taken (Fig. 2 B).

Digital images were imported into a computer as JPEG files, and the position of each plant in the pictures was determined using GIS. This involved four steps: 1) A reference frame (Fig. 3) was established using R2V software to designate control points, or the four vertexes of each sub-block (Appendix S1), so that all plants in each sub-block were within the same reference frame. The parallax and optical distortion in the raster images was then geometrically corrected based on these selected control points; 2) Maps, or layers in GIS terminology, were set up for each species as PROJECT files (Appendix S2), and all individuals in each sub-block were digitized using R2V software (Appendix S3). For accuracy, the digitization of plant individual locations was performed manually; 3) Each plant species layer was exported from a PROJECT file to a SHAPE file in R2V software (Appendix S4); 4) Finally each species layer was opened in Arc GIS software in the SHAPE file format, and attribute data from each species layer was exported into Arc GIS to obtain the precise coordinates for each species. This last phase involved four steps of its own, from adding the data (Appendix S5), to opening the attribute table (Appendix S6), to adding new x and y coordinate fields (Appendix S7) and to obtaining the x and y coordinates and filling in the new fields (Appendix S8).

  1. Data reliability assessment

To determine the accuracy of our new method, we measured the individual locations of Leymus chinensis, a perennial rhizome grass, in representative community blocks 5 m x 5 m in size in typical steppe habitat in the Inner Mongolia Autonomous Region of China in July 2010 (Fig. 4 A). As our standard for comparison, we used a ruler to measure the individual coordinates of L. chinensis. We tested for significant differences between (1) the coordinates of L. chinensis, as measured with our new method and with the ruler, and (2) the pair correlation function g of L. chinensis, as measured with our new method and with the ruler (see section 3.2 Data Analysis). If (1) the coordinates of L. chinensis, as measured with our new method and with the ruler, and (2) the pair correlation function g of L. chinensis, as measured with our new method and with the ruler, did not differ significantly, then we could conclude that our new method of measuring the coordinates of L. chinensis was reliable.

We compared the results using a t-test (Table 1). We found no significant differences in either (1) the coordinates of L. chinensis or (2) the pair correlation function g of L. chinensis. Further, we compared the pattern characteristics of L. chinensis when measured by our new method against the ruler measurements using a null model. We found that the two pattern characteristics of L. chinensis did not differ significantly based on the homogenous Poisson process or complete spatial randomness (Fig. 4 B). Thus, we concluded that the data obtained using our new method was reliable enough to perform point pattern analysis with a null model in grassland communities.

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