52 datasets found
  1. TIGER/Line Shapefile, 2021, State, Alabama, Census Tracts

    • catalog.data.gov
    Updated Nov 1, 2022
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    U.S. Department of Commerce, U.S. Census Bureau, Geography Division, Spatial Data Collection and Products Branch (Publisher) (2022). TIGER/Line Shapefile, 2021, State, Alabama, Census Tracts [Dataset]. https://catalog.data.gov/dataset/tiger-line-shapefile-2021-state-alabama-census-tracts
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    Dataset updated
    Nov 1, 2022
    Dataset provided by
    United States Census Bureauhttp://census.gov/
    Description

    The TIGER/Line shapefiles and related database files (.dbf) are an extract of selected geographic and cartographic information from the U.S. Census Bureau's Master Address File / Topologically Integrated Geographic Encoding and Referencing (MAF/TIGER) Database (MTDB). The MTDB represents a seamless national file with no overlaps or gaps between parts, however, each TIGER/Line shapefile is designed to stand alone as an independent data set, or they can be combined to cover the entire nation. Census tracts are small, relatively permanent statistical subdivisions of a county or equivalent entity, and were defined by local participants as part of the 2020 Census Participant Statistical Areas Program. The Census Bureau delineated the census tracts in situations where no local participant existed or where all the potential participants declined to participate. The primary purpose of census tracts is to provide a stable set of geographic units for the presentation of census data and comparison back to previous decennial censuses. Census tracts generally have a population size between 1,200 and 8,000 people, with an optimum size of 4,000 people. When first delineated, census tracts were designed to be homogeneous with respect to population characteristics, economic status, and living conditions. The spatial size of census tracts varies widely depending on the density of settlement. Physical changes in street patterns caused by highway construction, new development, and so forth, may require boundary revisions. In addition, census tracts occasionally are split due to population growth, or combined as a result of substantial population decline. Census tract boundaries generally follow visible and identifiable features. They may follow legal boundaries such as minor civil division (MCD) or incorporated place boundaries in some States and situations to allow for census tract-to-governmental unit relationships where the governmental boundaries tend to remain unchanged between censuses. State and county boundaries always are census tract boundaries in the standard census geographic hierarchy. In a few rare instances, a census tract may consist of noncontiguous areas. These noncontiguous areas may occur where the census tracts are coextensive with all or parts of legal entities that are themselves noncontiguous. For the 2010 Census and beyond, the census tract code range of 9400 through 9499 was enforced for census tracts that include a majority American Indian population according to Census 2000 data and/or their area was primarily covered by federally recognized American Indian reservations and/or off-reservation trust lands; the code range 9800 through 9899 was enforced for those census tracts that contained little or no population and represented a relatively large special land use area such as a National Park, military installation, or a business/industrial park; and the code range 9900 through 9998 was enforced for those census tracts that contained only water area, no land area.

  2. a

    2020 and 2021 Population Estimates by Urban Cluster

    • mapdirect-fdep.opendata.arcgis.com
    • gis-fdot.opendata.arcgis.com
    • +2more
    Updated Aug 9, 2023
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    Florida Department of Transportation (2023). 2020 and 2021 Population Estimates by Urban Cluster [Dataset]. https://mapdirect-fdep.opendata.arcgis.com/items/e5ba6791edde443aae860f67513e5c98
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    Dataset updated
    Aug 9, 2023
    Dataset authored and provided by
    Florida Department of Transportation
    Area covered
    Description

    Each year, the Forecasting and Trends Office (FTO) publishes population estimates and future year projections. The population estimates can be used for a variety of planning studies including statewide and regional transportation plan updates, subarea and corridor studies, and funding allocations for various planning agencies.The 2020 population estimates reported are based on the US Census Bureau 2020 Decennial Census. The 2021 population estimates are based on the population estimates developed by the Bureau of Economic and Business Research (BEBR) at the University of Florida. BEBR uses the decennial census count for April 1, 2020, as the starting point for state-level projections. More information is available from BEBR here.This dataset contains boundaries for all 2010 Census Urban Clusters (UCs) in the State of Florida with 2020 census population and 2021 population estimates. All legal boundaries and names in this dataset are from the US Census Bureau’s TIGER/Line Files (2021).BEBR provides 2021 population estimates for counties in Florida. However, UC boundaries may not coincide with the jurisdictional boundaries of counties and UCs often spread into several counties. To estimate the population for an UC, first the ratio of the subject UC that is contained within a county (or sub-area) to the area of the entire county was determined. That ratio was multiplied by the estimated county population to obtain the population for that sub-area. The population for the entire UC is the sum of all sub-area populations estimated from the counties they are located within.For the 2010 Census, urban areas comprised a “densely settled core of census tracts and/or census blocks that meet minimum population density requirements, along with adjacent territory containing non-residential urban land uses as well as territory with low population density included to link outlying densely settled territory with the densely settled core.” In 2010, the US Census Bureau identified two types of urban areas—Urbanized Areas (UAs) and UCs. UCs have a population of at least 2,500 and less than 50,000 people. Note: Century, FL--AL Urban Cluster is located in two states: Florida (Escambia County) and Alabama (Escambia County). 2021 population of Escambia County, AL used for this estimation is from the US Census annual population estimates (2020-2021). All other Urban Clusters are located entirely within the state of Florida. Please see the Data Dictionary for more information on data fields. Data Sources:US Census Bureau 2020 Decennial CensusUS Census Bureau’s TIGER/Line Files (2021)Bureau of Economic and Business Research (BEBR) – Florida Estimates of Population 2021 Data Coverage: StatewideData Time Period: 2020 – 2021 Date of Publication: July 2022 Point of Contact:Dana Reiding, ManagerForecasting and Trends OfficeFlorida Department of TransportationDana.Reiding@dot.state.fl.us605 Suwannee Street, Tallahassee, Florida 32399850-414-4719

  3. 2021 Population Density by Urbanized Area

    • mapdirect-fdep.opendata.arcgis.com
    • arc-gis-hub-home-arcgishub.hub.arcgis.com
    Updated Aug 9, 2023
    + more versions
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    Florida Department of Transportation (2023). 2021 Population Density by Urbanized Area [Dataset]. https://mapdirect-fdep.opendata.arcgis.com/datasets/a80ae26e54f349bead882a9ab11a0fc0
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    Dataset updated
    Aug 9, 2023
    Dataset authored and provided by
    Florida Department of Transportationhttps://www.fdot.gov/
    Area covered
    Description

    Each year, the Forecasting and Trends Office (FTO) publishes population estimates and future year projections. The population estimates can be used for a variety of planning studies including statewide and regional transportation plan updates, subarea and corridor studies, and funding allocations for various planning agencies. The 2021 population estimates are based on the population estimates developed by the Bureau of Economic and Business Research (BEBR) at the University of Florida. BEBR uses the decennial census count for April 1, 2020, as the starting point for state-level projections. More information is available from BEBR here. This dataset contains boundaries for all 2010 Census Urbanized Areas (UAs) in the State of Florida with 2021 population density estimates. All legal boundaries and names in this dataset are from the US Census Bureau’s TIGER/Line Files (2021). BEBR provides 2021 population estimates for counties in Florida. However, UA boundaries may not coincide with the jurisdictional boundaries of counties and UAs often spread into several counties. To estimate the population for an UA, first the ratio of the subject UA that is contained within a county (or sub-area) to the area of the entire county was determined. That ratio was multiplied by the estimated county population to obtain the population for that sub-area. The population for the entire UA is the sum of all sub-area populations estimated from the counties they are located within. For the 2010 Census, urban areas comprised a “densely settled core of census tracts and/or census blocks that meet minimum population density requirements, along with adjacent territory containing non-residential urban land uses as well as territory with low population density included to link outlying densely settled territory with the densely settled core.” In 2010, the US Census Bureau identified two types of urban areas—UAs and Urban Clusters (UCs). UAs have a population of 50,000 or more people. Note: Pensacola, FL--AL Urbanized Area is located in two states: Florida (Escambia County and Santa Rosa County) and Alabama (Baldwin County). 2021 population of Baldwin County, AL used for this estimation is from the US Census annual population estimates (2020-2021). All other Urbanized Areas are located entirely within the state of Florida. Please see the Data Dictionary for more information on data fields. Data Sources:FDOT FTO 2020 and 2021 Population Estimates by Urbanized Area and CountyUS Census Bureau 2020 Decennial CensusUS Census Bureau’s TIGER/Line Files (2021)Bureau of Economic and Business Research (BEBR) – Florida Estimates of Population 2021 Data Coverage: StatewideData Time Period: 2021 Date of Publication: October 2022 Point of Contact:Dana Reiding, ManagerForecasting and Trends OfficeFlorida Department of TransportationDana.Reiding@dot.state.fl.us605 Suwannee Street, Tallahassee, Florida 32399850-414-4719

  4. A

    Albania AL: Population Density: People per Square Km

    • ceicdata.com
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    CEICdata.com, Albania AL: Population Density: People per Square Km [Dataset]. https://www.ceicdata.com/en/albania/population-and-urbanization-statistics/al-population-density-people-per-square-km
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    Dataset provided by
    CEICdata.com
    License

    Attribution 4.0 (CC BY 4.0)https://creativecommons.org/licenses/by/4.0/
    License information was derived automatically

    Time period covered
    Dec 1, 2011 - Dec 1, 2022
    Area covered
    Albania
    Variables measured
    Population
    Description

    Albania Population Density: People per Square Km data was reported at 101.376 Person/sq km in 2022. This records a decrease from the previous number of 102.616 Person/sq km for 2021. Albania Population Density: People per Square Km data is updated yearly, averaging 105.288 Person/sq km from Dec 1961 (Median) to 2022, with 62 observations. The data reached an all-time high of 119.947 Person/sq km in 1990 and a record low of 60.577 Person/sq km in 1961. Albania Population Density: People per Square Km data remains active status in CEIC and is reported by World Bank. The data is categorized under Global Database’s Albania – Table AL.World Bank.WDI: Population and Urbanization Statistics. Population density is midyear population divided by land area in square kilometers. Population is based on the de facto definition of population, which counts all residents regardless of legal status or citizenship--except for refugees not permanently settled in the country of asylum, who are generally considered part of the population of their country of origin. Land area is a country's total area, excluding area under inland water bodies, national claims to continental shelf, and exclusive economic zones. In most cases the definition of inland water bodies includes major rivers and lakes.;Food and Agriculture Organization and World Bank population estimates.;Weighted average;

  5. d

    2015 Cartographic Boundary File, Urban Area-State-County for Alabama,...

    • catalog.data.gov
    Updated Jan 13, 2021
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    (2021). 2015 Cartographic Boundary File, Urban Area-State-County for Alabama, 1:500,000 [Dataset]. https://catalog.data.gov/dataset/2015-cartographic-boundary-file-urban-area-state-county-for-alabama-1-5000001
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    Dataset updated
    Jan 13, 2021
    Description

    The 2015 cartographic boundary shapefiles are simplified representations of selected geographic areas from the U.S. Census Bureau's Master Address File / Topologically Integrated Geographic Encoding and Referencing (MAF/TIGER) Database (MTDB). These boundary files are specifically designed for small-scale thematic mapping. When possible, generalization is performed with the intent to maintain the hierarchical relationships among geographies and to maintain the alignment of geographies within a file set for a given year. Geographic areas may not align with the same areas from another year. Some geographies are available as nation-based files while others are available only as state-based files. The records in this file allow users to map the parts of Urban Areas that overlap a particular county. After each decennial census, the Census Bureau delineates urban areas that represent densely developed territory, encompassing residential, commercial, and other nonresidential urban land uses. In general, this territory consists of areas of high population density and urban land use resulting in a representation of the "urban footprint." There are two types of urban areas: urbanized areas (UAs) that contain 50,000 or more people and urban clusters (UCs) that contain at least 2,500 people, but fewer than 50,000 people (except in the U.S. Virgin Islands and Guam which each contain urban clusters with populations greater than 50,000). Each urban area is identified by a 5-character numeric census code that may contain leading zeroes. The primary legal divisions of most states are termed counties. In Louisiana, these divisions are known as parishes. In Alaska, which has no counties, the equivalent entities are the organized boroughs, city and boroughs, municipalities, and for the unorganized area, census areas. The latter are delineated cooperatively for statistical purposes by the State of Alaska and the Census Bureau. In four states (Maryland, Missouri, Nevada, and Virginia), there are one or more incorporated places that are independent of any county organization and thus constitute primary divisions of their states. These incorporated places are known as independent cities and are treated as equivalent entities for purposes of data presentation. The District of Columbia and Guam have no primary divisions, and each area is considered an equivalent entity for purposes of data presentation. The Census Bureau treats the following entities as equivalents of counties for purposes of data presentation: Municipios in Puerto Rico, Districts and Islands in American Samoa, Municipalities in the Commonwealth of the Northern Mariana Islands, and Islands in the U.S. Virgin Islands. The entire area of the United States, Puerto Rico, and the Island Areas is covered by counties or equivalent entities. The boundaries for counties and equivalent entities are as of January 1, 2010.

  6. a

    Gridded Population of the World (GPWv4) UN-Adjusted Population Density 2015

    • uneca.africageoportal.com
    • hub.arcgis.com
    Updated Nov 4, 2016
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    Columbia (2016). Gridded Population of the World (GPWv4) UN-Adjusted Population Density 2015 [Dataset]. https://uneca.africageoportal.com/maps/6e4a2f8cf7564fa499e58a4a87e6c7f1
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    Dataset updated
    Nov 4, 2016
    Dataset authored and provided by
    Columbia
    License

    MIT Licensehttps://opensource.org/licenses/MIT
    License information was derived automatically

    Area covered
    Description

    GPWv4 is a gridded data product that depicts global population data from the 2010 round of Population and Housing Censuses. The Population Density, 2015 layer represents persons per square kilometer for year 2015. Data Summary:GPWv4 is constructed from national or subnational input areal units of varying resolutions. The native grid cell size is 30 arc-seconds, or ~1 km at the equator. Separate grids are available for population count, population density, estimated land area, and data quality indicators; which include the water mask represented in this service. Population estimates are derived by extrapolating the raw census counts to estimates for the 2010 target year. The development of GPWv4 builds upon previous versions of the data set (Tobler et al., 1997; Deichmann et al., 2001; Balk et al., 2006).The full GPWv4 data collection will consist of population estimates for the years 2000, 2005, 2010, 2015, and 2020, and will include grids for estimates of total population, age, sex, and urban/rural status. However, this release consists only of total population estimates for the year 2015. This data is being released now to allow users access to the population grids.Recommended Citation:Center for International Earth Science Information Network - CIESIN - Columbia University. 2016. Gridded Population of the World, Version 4 (GPWv4): Population Density. Palisades, NY: NASA Socioeconomic Data and Applications Center (SEDAC). http://dx.doi.org/10.7927/H4NP22DQ. Accessed DAY MONTH YEAR

  7. u

    Data from: Data and code for "Sustainable Human Population Density in...

    • investigacion.ubu.es
    • investigacion.cenieh.es
    • +1more
    Updated 2022
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    Rodríguez, Jesús; Sommer, Christian; Willmes, Christian; Mateos, Ana; Rodríguez, Jesús; Sommer, Christian; Willmes, Christian; Mateos, Ana (2022). Data and code for "Sustainable Human Population Density in Western Europe between 560.000 and 360.000 years ago" [Dataset]. https://investigacion.ubu.es/documentos/67321e95aea56d4af048594b
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    Dataset updated
    2022
    Authors
    Rodríguez, Jesús; Sommer, Christian; Willmes, Christian; Mateos, Ana; Rodríguez, Jesús; Sommer, Christian; Willmes, Christian; Mateos, Ana
    Area covered
    Western Europe
    Description

    This dataset contains the modeling results GIS data (maps) of the study “Sustainable Human Population Density in Western Europe between 560.000 and 360.000 years ago” by Rodríguez et al. (2022). The NPP data (npp.zip) was computed using an empirical formula (the Miami model) from palaeo temperature and palaeo precipitation data aggregated for each timeslice from the Oscillayers dataset (Gamisch, 2019), as defined in Rodríguez et al. (2022, in review). The Population densities file (pop_densities.zip) contains the computed minimum and maximum population densities rasters for each of the defined MIS timeslices. With the population density value Dc in logarithmic form log(Dc). The Species Distribution Model (sdm.7z) includes input data (folder /data), intermediate results (folder /work) and results and figures (folder /results). All modelling steps are included as an R project in the folder /scripts. The R project is subdivided into individual scripts for data preparation (1.x), sampling procedure (2.x), and model computation (3.x). The habitat range estimation (habitat_ranges.zip) includes the potential spatial boundaries of the hominin habitat as binary raster files with 1=presence and 0=absence. The ranges rely on a dichotomic classification of the habitat suitability with a threshold value inferred from the 5% quantile of the presence data. The habitat suitability (habitat_suitability.zip) is the result of the Species Distribution Modelling and describes the environmental suitability for hominin presence based on the sites considered in this study. The values range between 0=low and 1=high suitability. The dataset includes the mean (pred_mean) and standard deviation (pred_std) of multiple model runs.

  8. Population density estimation and land use database for Al Geneina and El...

    • data.europa.eu
    Updated Feb 18, 2013
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    Joint Research Centre (2013). Population density estimation and land use database for Al Geneina and El Daein, Sudan (2013-02-18) [Dataset]. https://data.europa.eu/data/datasets/f6e3cfac-e172-40a2-b5c3-49092505c9e8?locale=et
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    esri file geodatabaseAvailable download formats
    Dataset updated
    Feb 18, 2013
    Dataset authored and provided by
    Joint Research Centrehttps://joint-research-centre.ec.europa.eu/index_en
    License

    http://data.europa.eu/eli/dec/2011/833/ojhttp://data.europa.eu/eli/dec/2011/833/oj

    Area covered
    El Daein, Sudan, Al Junaynah
    Description


    Activation date: 2013-02-18
    Event type: Humanitarian

    Activation reason:
    The International Committee of the Red Cross is requesting the non-rush GIO-EMS service to characterize the built-up of the Darfur (Sudan) cities of Al Geneina and El Daein. The purpose of the requested analysis is to map the informal and formal settlements and the non-residential city structures to derive population estimates and population densities per sector to facilitate the planning and estimation of the needs for an urban water network.

  9. GlobPOP: A 33-year (1990-2022) global gridded population dataset (Version...

    • zenodo.org
    tiff
    Updated Sep 4, 2024
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    Luling Liu; Xin Cao; Xin Cao; Shijie Li; Na Jie; Luling Liu; Shijie Li; Na Jie (2024). GlobPOP: A 33-year (1990-2022) global gridded population dataset (Version 2.0-test-alpha) [Dataset]. http://doi.org/10.5281/zenodo.11071249
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    tiffAvailable download formats
    Dataset updated
    Sep 4, 2024
    Dataset provided by
    Zenodohttp://zenodo.org/
    Authors
    Luling Liu; Xin Cao; Xin Cao; Shijie Li; Na Jie; Luling Liu; Shijie Li; Na Jie
    License

    Attribution 4.0 (CC BY 4.0)https://creativecommons.org/licenses/by/4.0/
    License information was derived automatically

    Description

    Data Usage Notice

    This version is not recommended for download. Please check the newest version.

    We would like to inform you that the updated GlobPOP dataset (2021-2022) have been available in version 2.0. The GlobPOP dataset (2021-2022) in the current version is not recommended for your work. The GlobPOP dataset (1990-2020) in the current version is the same as version 1.0.

    Thank you for your continued support of the GlobPOP.

    If you encounter any issues, please contact us via email at lulingliu@mail.bnu.edu.cn.

    Introduction

    Continuously monitoring global population spatial dynamics is essential for implementing effective policies related to sustainable development, such as epidemiology, urban planning, and global inequality.

    Here, we present GlobPOP, a new continuous global gridded population product with a high-precision spatial resolution of 30 arcseconds from 1990 to 2020. Our data-fusion framework is based on cluster analysis and statistical learning approaches, which intends to fuse the existing five products(Global Human Settlements Layer Population (GHS-POP), Global Rural Urban Mapping Project (GRUMP), Gridded Population of the World Version 4 (GPWv4), LandScan Population datasets and WorldPop datasets to a new continuous global gridded population (GlobPOP). The spatial validation results demonstrate that the GlobPOP dataset is highly accurate. To validate the temporal accuracy of GlobPOP at the country level, we have developed an interactive web application, accessible at https://globpop.shinyapps.io/GlobPOP/, where data users can explore the country-level population time-series curves of interest and compare them with census data.

    With the availability of GlobPOP dataset in both population count and population density formats, researchers and policymakers can leverage our dataset to conduct time-series analysis of population and explore the spatial patterns of population development at various scales, ranging from national to city level.

    Data description

    The product is produced in 30 arc-seconds resolution(approximately 1km in equator) and is made available in GeoTIFF format. There are two population formats, one is the 'Count'(Population count per grid) and another is the 'Density'(Population count per square kilometer each grid)

    Each GeoTIFF filename has 5 fields that are separated by an underscore "_". A filename extension follows these fields. The fields are described below with the example filename:

    GlobPOP_Count_30arc_1990_I32

    Field 1: GlobPOP(Global gridded population)
    Field 2: Pixel unit is population "Count" or population "Density"
    Field 3: Spatial resolution is 30 arc seconds
    Field 4: Year "1990"
    Field 5: Data type is I32(Int 32) or F32(Float32)

    More information

    Please refer to the paper for detailed information:

    Liu, L., Cao, X., Li, S. et al. A 31-year (1990–2020) global gridded population dataset generated by cluster analysis and statistical learning. Sci Data 11, 124 (2024). https://doi.org/10.1038/s41597-024-02913-0.

    The fully reproducible codes are publicly available at GitHub: https://github.com/lulingliu/GlobPOP.

  10. w

    National Fish Habitat Action Plan (NFHAP) 2010 HCI Scores and Human...

    • data.wu.ac.at
    shp
    Updated May 10, 2018
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    Department of the Interior (2018). National Fish Habitat Action Plan (NFHAP) 2010 HCI Scores and Human Disturbance Data (linked to NHDPLUSV1) for Alabama [Dataset]. https://data.wu.ac.at/schema/data_gov/MmVhMzc0MTAtNmE3YS00MWEwLWJmN2MtN2I2YjRlMTNhZGMx
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    shpAvailable download formats
    Dataset updated
    May 10, 2018
    Dataset provided by
    Department of the Interior
    Area covered
    d1214959dc4cc68130339ae2255c145cb366a993
    Description

    This shapefile contains landscape factors representing human disturbances summarized to local and network catchments of river reaches for the state of Alabama. This dataset is the result of clipping the feature class 'NFHAP 2010 HCI Scores and Human Disturbance Data for the Conterminous United States linked to NHDPLUSV1.gdb' to the state boundary of Alabama. Landscape factors include land uses, population density, roads, dams, mines, and point-source pollution sites. The source datasets that were compiled and attributed to catchments were identified as being: (1) meaningful for assessing fish habitat; (2) consistent across the entire study area in the way that they were assembled; (3) representative of conditions in the past 10 years, and (4) of sufficient spatial resolution that they could be used to make valid comparisons among local catchment units. In this data set, these variables are linked to the catchments of the National Hydrography Dataset Plus Version 1 (NHDPlusV1) using the COMID identifier. They can also be linked to the reaches of the NHDPlusV1 using the COMID identifier. Catchment attributes are available for both local catchments (defined as the land area draining directly to a reach; attributes begin with "L_" prefix) and network catchments (defined by all upstream contributing catchments to the reach's outlet, including the reach's own local catchment; attributes begin with "N_" prefix). This shapefile also includes habitat condition scores created based on responsiveness of biological metrics to anthropogenic landscape disturbances throughout ecoregions. Separate scores were created by considering disturbances within local catchments, network catchments, and a cumulative score that accounted for the most limiting disturbance operating on a given biological metric in either local or network catchments. This assessment only scored reaches representing streams and rivers (see the process section for more details). Please use the following citation: Esselman, P., D.M. Infante, L. Wang, W. Taylor, W. Daniel, R. Tingley, J. Fenner, A. Cooper, D. Wieferich, D. Thornbrugh and J. Ross. (April 2011) National Fish Habitat Action Plan (NFHAP) 2010 HCI Scores and Human Disturbance Data (linked to NHDPLUSV1) for Alabama. National Fish Habitat Partnership Data System. http://dx.doi.org/doi:10.5066/F7XP72XG

  11. f

    Data from: Population density and vegetation resources influence demography...

    • datasetcatalog.nlm.nih.gov
    • figshare.com
    Updated Jun 26, 2024
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    Dobson, F. Stephen; Viblanc, Vincent A; Tamian, Anouch; Saraux, Claire (2024). Population density and vegetation resources influence demography in a hibernating herbivorous mammal [Dataset]. https://datasetcatalog.nlm.nih.gov/dataset?q=0001468941
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    Dataset updated
    Jun 26, 2024
    Authors
    Dobson, F. Stephen; Viblanc, Vincent A; Tamian, Anouch; Saraux, Claire
    Description

    This data set concerns the paper by Tamian et al. 2024 "Population density and vegetation resources influence demography in a hibernating herbivorous mammal" published in Oecologia. The study examines how forage availability (vegetation assessed through NDVI) and population density affected the functional traits and demographic rates of a population of Columbian ground squirrels (Urocitellus columbianus), over a 32-year period.

  12. Calculations for “Thought Experiment”.

    • plos.figshare.com
    • datasetcatalog.nlm.nih.gov
    xlsx
    Updated Jun 1, 2023
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    John W. Hargrove; John Van Sickle; Glyn A. Vale; Eric R. Lucas (2023). Calculations for “Thought Experiment”. [Dataset]. http://doi.org/10.1371/journal.pntd.0009026.s003
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    xlsxAvailable download formats
    Dataset updated
    Jun 1, 2023
    Dataset provided by
    PLOShttp://plos.org/
    Authors
    John W. Hargrove; John Van Sickle; Glyn A. Vale; Eric R. Lucas
    License

    Attribution 4.0 (CC BY 4.0)https://creativecommons.org/licenses/by/4.0/
    License information was derived automatically

    Description

    Data from Opiro (2017). Table A in S3 Table. Data kindly provided by Dr Thierry de Meeûs. Table B in S3 Table. Simulations used to estimate dispersal parameters where there may be errors of estimation for b, S and Ne. Fig A in S3 Table. Simulations illustrating the false signal of NDDD in a field study. Parameter estimates generated for 10 different trap displacement choices applied to the Opiro et al. (2017) study of G. f. fuscipes in Uganda. A. Dispersal distances (log()) vs effective population density (log()). B. Dispersal distance (log()) vs surface area (log()) occupied by the effective population. C. Regression coefficient (log()) vs effective population density (log()). D. Effective population size (log()) vs effective population density (log()). E. Effective population size (log()) vs surface area (log()) occupied by the effective population. F. Surface area (log()) occupied by the effective population vs effective population density (log()). Fig B in S3 Table. Simulations using Opiro et al (2017) data, with or without error. Row A: Results of de Meeûs et al. (2019) for comparison. Row B: Recalculation of Opiro et al (2017) results for varying trap displacements, with error. Row C: Recalculation of Opiro et al (2017) results for varying trap displacements without error. (XLSX)

  13. U

    1990 census of population and housing. Block statistics. East South Central...

    • dataverse-staging.rdmc.unc.edu
    • datasearch.gesis.org
    Updated Apr 3, 2012
    + more versions
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    UNC Dataverse (2012). 1990 census of population and housing. Block statistics. East South Central division. Alabama, Kentucky, Mississippi, Tennessee [Dataset]. https://dataverse-staging.rdmc.unc.edu/dataset.xhtml?persistentId=hdl:1902.29/CD-10921
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    Dataset updated
    Apr 3, 2012
    Dataset provided by
    UNC Dataverse
    License

    https://dataverse-staging.rdmc.unc.edu/api/datasets/:persistentId/versions/1.0/customlicense?persistentId=hdl:1902.29/CD-10921https://dataverse-staging.rdmc.unc.edu/api/datasets/:persistentId/versions/1.0/customlicense?persistentId=hdl:1902.29/CD-10921

    Area covered
    Kentucky, Tennessee, Alabama
    Description

    1 computer laser optical disc ; 4 3/4 in.Selected block-level data from Summary tape file 1B, including total population, age, race, and Hispanic origin, number of housing units, tenure, room density, mean contract rent, mean value, and mean number of rooms in housing units.

  14. e

    McDonald et al. data on tree cover (2014-2016) at the US census block level...

    • knb.ecoinformatics.org
    • dataone.org
    • +1more
    Updated Jan 1, 2021
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    Robert McDonald (2021). McDonald et al. data on tree cover (2014-2016) at the US census block level for the 100 largest urbanized areas [Dataset]. http://doi.org/10.5063/MS3R5F
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    Dataset updated
    Jan 1, 2021
    Dataset provided by
    Knowledge Network for Biocomplexity
    Authors
    Robert McDonald
    Time period covered
    Jan 1, 2014 - Jan 1, 2016
    Area covered
    Description

    This dataset is associated with the McDonald et al. paper, entitled "The urban tree cover and temperature disparity in US urbanized areas: Quantifying the effect of income across 5,723 communities". Urban tree cover provides benefits to human health and well-being, but previous studies suggest that tree cover is often inequitably distributed. Here, we use NAIP imagery to survey the tree cover inequality for Census blocks in US large urbanized areas, home to 167 million people across 5,723 municipalities and other places. We compared tree cover to summer surface temperature, as measured using Thematic Mapper imagery. In 92% of the urbanized areas surveyed, low-income blocks have less tree cover than high-income blocks. On average, low-income blocks have 15.2% less tree cover and are 1.5⁰C hotter (surface temperature) than high-income blocks. The greatest difference between low- and high-income blocks was found in urbanized areas in the Northeast of the United States, where low-income blocks often have at least 30% less tree cover and are at least 4.0⁰C hotter. Even after controlling for population density and built-up intensity, the association between income and tree cover is significant, as is the association between race and tree cover. We estimate, after controlling for population density, that low-income blocks have 62 million fewer trees than high-income blocks, a compensatory value of $56 billion dollars ($1,349/person). An investment in tree planting and natural regeneration of $17.6 billion would close the tree cover disparity for 42 million people in low-income blocks.

  15. c

    Data from: WorldPop

    • civicdataspace.in
    Updated Jul 19, 2024
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    CivicDataSpace (2024). WorldPop [Dataset]. https://civicdataspace.in/datasets/7343af3c-f892-4610-b528-2444857b2081
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    Dataset updated
    Jul 19, 2024
    Dataset provided by
    CivicDataSpace
    Description

    WorldPop (Lloyd et al., 2019) utilizes machine learning to get the correlations between population densities and a range of geographic covariate layers to dis-aggregate current census-based population counts into 1 km x 1 km and 100x100m grid cells using Random Forest-based asymmetric redistribution. IDS-DRR uses the Unconstrained individual countries 2000-2020 UN adjusted (100 m resolution) population counts data estimates for 2017 to 2020 from the WorldPop. For the remaining years, we use the annual growth rate calculated from the population estimates of 2015 and 2020 to project the population for 2021, 2022 and 2023 using linear regression extrapolation

  16. External Data: Demographic shifts, inter-group contact, and environmental...

    • figshare.com
    application/x-dbf
    Updated Mar 5, 2025
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    Marco Túlio Pacheco Coelho; Hannah J. Haynie; Claire Bowern; Robert K. Colwell; Simon J. Greenhill; Kathryn R. Kirby; Thiago F. Rangel; Michael C. Gavin (2025). External Data: Demographic shifts, inter-group contact, and environmental conditions drive language extinction and diversification [Dataset]. http://doi.org/10.6084/m9.figshare.28539116.v1
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    application/x-dbfAvailable download formats
    Dataset updated
    Mar 5, 2025
    Dataset provided by
    Figsharehttp://figshare.com/
    Authors
    Marco Túlio Pacheco Coelho; Hannah J. Haynie; Claire Bowern; Robert K. Colwell; Simon J. Greenhill; Kathryn R. Kirby; Thiago F. Rangel; Michael C. Gavin
    License

    Attribution 4.0 (CC BY 4.0)https://creativecommons.org/licenses/by/4.0/
    License information was derived automatically

    Description

    Carrying Capacity EstimationsThe carrying capacity for individuals in this dataset is based on estimated population density (people per km²) for forager societies, as derived from Kavanagh et al. Using a fitted piecewise structural equation model, the authors estimated global population density at a 0.5° × 0.5° resolution.The corresponding raster dataset used in our simulation model is provided in this repository. This raster file is a spatial object in .asc format, where each cell value represents the estimated population density (people per km²) for that location. The file is named:4K_popD_raster_Dec.ascKavanagh, P. H. et al. Hindcasting global population densities reveals forces enabling the origin of agriculture. Nature human behaviour 2, 478 (2018).Language Diversity Data for North AmericaThe empirical richness pattern of language diversity in North America, as used in our simulation, is based on established literature and previously published language range maps.The final dataset is provided as a shapefile, containing:The name of each languageThe corresponding Glottolog identification codeThis shapefile can be found in this repository under the name:NAM_Continent.shpHaynie, H. J. & Gavin, M. C. Modern language range mapping for the study of language diversity. (2019).

  17. c

    Data from: WorldPop

    • civicdataspace.in
    Updated Jul 19, 2024
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    CivicDataSpace (2024). WorldPop [Dataset]. https://civicdataspace.in/datasets/cee2015f-850f-4bcc-b35c-9fbe26620b4a
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    Dataset updated
    Jul 19, 2024
    Dataset provided by
    CivicDataSpace
    Description

    WorldPop (Lloyd et al., 2019) utilizes machine learning to get the correlations between population densities and a range of geographic covariate layers to dis-aggregate current census-based population counts into 1 km x 1 km and 100x100m grid cells using Random Forest-based asymmetric redistribution. IDS-DRR uses the Unconstrained individual countries 2000-2020 UN adjusted (100 m resolution) population counts data estimates for 2017 to 2020 from the WorldPop. For the remaining years, we use the annual growth rate calculated from the population estimates of 2015 and 2020 to project the population for 2021, 2022, 2023, 2024 and 2025 using linear regression extrapolation

  18. n

    Demographic study of a tropical epiphytic orchid with stochastic simulations...

    • data.niaid.nih.gov
    • data-staging.niaid.nih.gov
    • +1more
    zip
    Updated Nov 14, 2022
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    Haydee Borrero; Ramona Oviedo-Prieto; Julio C. Alvarez; Tamara Ticktin; Mario Cisneros; Hong Liu (2022). Demographic study of a tropical epiphytic orchid with stochastic simulations of hurricanes, herbivory, episodic recruitment, and logging [Dataset]. http://doi.org/10.5061/dryad.vhhmgqnxd
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    zipAvailable download formats
    Dataset updated
    Nov 14, 2022
    Dataset provided by
    The Institute of Ecology and Systematics, National Herbarium of Cuba "Onaney Muñiz"
    Florida International University
    University of Hawaiʻi at Mānoa
    Authors
    Haydee Borrero; Ramona Oviedo-Prieto; Julio C. Alvarez; Tamara Ticktin; Mario Cisneros; Hong Liu
    License

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

    Description

    In a time of global change, having an understanding of the nature of biotic and abiotic factors that drive a species’ range may be the sharpest tool in the arsenal of conservation and management of threatened species. However, such information is lacking for most tropical and epiphytic species due to the complexity of life history, the roles of stochastic events, and the diversity of habitat across the span of a distribution. In this study, we conducted repeated censuses across the core and peripheral range of Trichocentrum undulatum, a threatened orchid that is found throughout the island of Cuba (species core range) and southern Florida (the northern peripheral range). We used demographic matrix modeling as well as stochastic simulations to investigate the impacts of herbivory, hurricanes, and logging (in Cuba) on projected population growth rates (? and ?s) among sites. Methods Field methods Censuses took place between 2013 and 2021. The longest census period was that of the Peripheral population with a total of nine years (2013–2021). All four populations in Cuba used in demographic modeling that were censused more than once: Core 1 site (2016–2019, four years), Core 2 site (2018–2019, two years), Core 3 (2016 and 2018 two years), and Core 4 (2018–2019, two years) (Appendix S1: Table S1). In November 2017, Hurricane Irma hit parts of Cuba and southern Florida, impacting the Peripheral population. The Core 5 population (censused on 2016 and 2018) was small (N=17) with low survival on the second census due to logging. Three additional populations in Cuba were visited only once, Core 6, Core 7, and Core 8 (Table 1). Sites with one census or with a small sample size (Core 5) were not included in the life history and matrix model analyses of this paper due to the lack of population transition information, but they were included in the analysis on the correlation between herbivory and fruit rate, as well as the use of mortality observations from logging for modeling. All Cuban sites were located between Western and Central Cuba, spanning four provinces: Mayabeque (Core 1), Pinar del Rio (Core 2 and Core 6), Matanzas (Core 3 and Core 5), and Sancti Spiritus (Core 4, Core 7, Core 8). At each population of T. undulatum presented in this study, individuals were studied within ~1-km strips where T. undulatum occurrence was deemed representative of the site, mostly occurring along informal forest trails. Once an individual of T. undulatum was located, all trees within a 5-m radius were searched for additional individuals. Since tagging was not permitted, we used a combination of information to track individual plants for the repeated censuses. These include the host species, height of the orchid, DBH of the host tree, and hand-drawn maps. Individual plants were also marked by GPS at the Everglades Peripheral site. If a host tree was found bearing more than one T. undulatum, then we systematically recorded the orchids in order from the lowest to highest as well as used the previous years’ observations in future censuses for individualized notes and size records. We recorded plant size and reproductive variables during each census including: the number of leaves, length of the longest leaf (cm), number of inflorescence stalks, number of flowers, and the number of mature fruits. We also noted any presence of herbivory, such as signs of being bored by M. miamensis, and whether an inflorescence was partially or completely affected by the fly, and whether there was other herbivory, such as D. boisduvalii on leaves. We used logistic regression analysis to examine the effects of year (at the Peripheral site) and sites (all sites) on the presence or absence of inflorescence herbivory at all the sites. Cross tabulation and chi-square analysis were done to examine the associations between whether a plant was able to fruit and the presence of floral herbivory by M. miamensis. The herbivory was scored as either complete or partial. During the orchid population scouting expeditions, we came across a small population in the Matanzas province (Core 5, within 10 km of the Core 3 site) and recorded the demographic information. Although the sampled population was small (N = 17), we were able to observe logging impacts at the site and recorded logging-associated mortality on the subsequent return to the site. Matrix modeling Definition of size-stage classes To assess the life stage transitions and population structures for each plant for each population’s census period we first defined the stage classes for the species. The categorization for each plant’s stage class depended on both its size and reproductive capabilities, a method deemed appropriate for plants (Lefkovitch 1965, Cochran and Ellner 1992). A size index score was calculated for each plant by taking the total number of observed leaves and adding the length of the longest leaf, an indication of accumulated biomass (Borrero et al. 2016). The smallest plant size that attempted to produce an inflorescence is considered the minimum size for an adult plant. Plants were classified by stage based on their size index and flowering capacity as the following: (1) seedlings (or new recruits), i.e., new and small plants with a size index score of less than 6, (2) juveniles, i.e., plants with a size index score of less than 15 with no observed history of flowering, (3) adults, plants with size index scores of 15 or greater. Adult plants of this size or larger are capable of flowering but may not produce an inflorescence in a given year. The orchid’s population matrix models were constructed based on these stages. In general, orchid seedlings are notoriously difficult to observe and easily overlooked in the field due to the small size of protocorms. A newly found juvenile on a subsequent site visit (not the first year) may therefore be considered having previously been a seedling in the preceding year. In this study, we use the discovered “seedlings” as indicatory of recruitment for the populations. Adult plants are able to shrink or transition into the smaller juvenile stage class, but a juvenile cannot shrink to the seedling stage. Matrix elements and population vital rates calculations Annual transition probabilities for every stage class were calculated. A total of 16 site- and year-specific matrices were constructed. When seedling or juvenile sample sizes were < 9, the transitions were estimated using the nearest year or site matrix elements as a proxy. Due to the length of the study and variety of vegetation types with a generally large population size at each site, transition substitutions were made with the average stage transition from all years at the site as priors. If the sample size of the averaged stage was still too small, the averaged transition from a different population located at the same vegetation type was used. We avoided using transition values from populations found in different vegetation types to conserve potential environmental differences. A total of 20% (27/135) of the matrix elements were estimated in this fashion, the majority being seedling stage transitions (19/27) and noted in the Appendices alongside population size (Appendix S1: Table S1). The fertility element transitions from reproductive adults to seedlings were calculated as the number of seedlings produced (and that survived to the census) per adult plant. Deterministic modeling analysis We used integral projection models (IPM) to project the long-term population growth rates for each time period and population. The finite population growth rate (?), stochastic long-term growth rate (?s), and the elasticity were projected for each matrices using R Popbio Package 2.4.4 (Stubben and Milligan 2007, Caswell 2001). The elasticity matrices were summarized by placing each element into one of three categories: fecundity (transition from reproductive adults to seedling stage), growth (all transitions to new and more advanced stage, excluding the fecundity), and stasis (plants that transitioned into the same or a less advanced stage on subsequent census) (Liu et al. 2005). Life table response experiments (LTREs) were conducted to identify the stage transitions that had the greatest effects on observed differences in population growth between select sites and years (i.e., pre-post hurricane impact and site comparisons of same vegetation type). Due to the frequent disturbances that epiphytes in general experience as well as our species’ distribution in hurricane-prone areas, we ran transient dynamic models that assume that the populations censused were not at stable stage distributions (Stott et al. 2011). We calculated three indices for short-term transient dynamics to capture the variation during a 15-year transition period: reactivity, maximum amplification, and amplified inertia. Reactivity measures a population’s growth in a single measured timestep relative to the stable-stage growth, during the simulated transition period. Maximum amplification and amplified inertia are the maximum of future population density and the maximum long-term population density, respectively, relative to a stable-stage population that began at the same initial density (Stott et al. 2011). For these analyses, we used a mean matrix for Core 1, Core 2 Core 3, and Core 4 sites and the population structure of their last census. For the Peripheral site, we averaged the last three matrices post-hurricane disturbance and used the most-recent population structure. We standardized the indices across sites with the assumption of initial population density equal to 1 (Stott et al. 2011). Analysis was done using R Popdemo version 1.3-0 (Stott et al. 2012b). Stochastic simulation We created matrices to simulate the effects of episodic recruitment, hurricane impacts, herbivory, and logging (Appendix S1: Table S2). The Peripheral population is the longest-running site with nine years of censuses (eight

  19. Data from: Population density of mesozooplankton during POLARSTERN cruise...

    • doi.pangaea.de
    • search.dataone.org
    html, tsv
    Updated 1997
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    Michiel M Rutgers van der Loeff; Victor Smetacek; Hein J W de Baar; Ulrich Bathmann; Karin Lochte (1997). Population density of mesozooplankton during POLARSTERN cruise ANT-X/6 [Dataset]. http://doi.org/10.1594/PANGAEA.88634
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    tsv, htmlAvailable download formats
    Dataset updated
    1997
    Dataset provided by
    PANGAEA
    Authors
    Michiel M Rutgers van der Loeff; Victor Smetacek; Hein J W de Baar; Ulrich Bathmann; Karin Lochte
    License

    Attribution 3.0 (CC BY 3.0)https://creativecommons.org/licenses/by/3.0/
    License information was derived automatically

    Time period covered
    Oct 12, 1992 - Nov 21, 1992
    Area covered
    Variables measured
    Index, Length, Species, DATE/TIME, Event label, DEPTH, water, Depth, top/min, Depth, bottom/max, Latitude of event, Elevation of event, and 4 more
    Description

    This dataset is about: Population density of mesozooplankton during POLARSTERN cruise ANT-X/6. Please consult parent dataset @ https://doi.org/10.1594/PANGAEA.728865 for more information.

  20. Bierhoff et al. 2024. Anthropogenic and climatic drivers of population...

    • figshare.com
    txt
    Updated Feb 25, 2024
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    Monica Bond; Lukas Bierhoff; Derek E. Lee; Arpat Ozgul (2024). Bierhoff et al. 2024. Anthropogenic and climatic drivers of population densities in an African savanna ungulate community [Dataset]. http://doi.org/10.6084/m9.figshare.16802242.v1
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    txtAvailable download formats
    Dataset updated
    Feb 25, 2024
    Dataset provided by
    figshare
    Figsharehttp://figshare.com/
    Authors
    Monica Bond; Lukas Bierhoff; Derek E. Lee; Arpat Ozgul
    License

    Attribution 4.0 (CC BY 4.0)https://creativecommons.org/licenses/by/4.0/
    License information was derived automatically

    Description

    Datasets (.csv files) of local population densities and spatial and temporal covariates for five species of ungulates (dik-dik, impala, Grant's gazelle, waterbuck, eland) in the Tarangire Ecosystem of northern Tanzania collected over 7 years.dik = dik-dik; ela = eland;gg = Grant's gazelle; imp = impala; wb = waterbuck.Bierhoff_et_al_2024_R_code: Contains the R code to rerun the entire analysis for Impala and to recreate the figures of the manuscript.table_test_1: A word document into which the tables from the R code can be saved. Note, whenever you rerun the create_table or create_table_for_dataframe function you will overwrite the last table that you created.Bierhoff_et.al_2024_Workspace: The workspace that contains all the necessary dataframes to run the R code, plus all data that are created by running the R script.Bierhoff_el_al_2024: The R project. To run the project click on this and you will open RStudio with the Rscript already loaded.

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U.S. Department of Commerce, U.S. Census Bureau, Geography Division, Spatial Data Collection and Products Branch (Publisher) (2022). TIGER/Line Shapefile, 2021, State, Alabama, Census Tracts [Dataset]. https://catalog.data.gov/dataset/tiger-line-shapefile-2021-state-alabama-census-tracts
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TIGER/Line Shapefile, 2021, State, Alabama, Census Tracts

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Dataset updated
Nov 1, 2022
Dataset provided by
United States Census Bureauhttp://census.gov/
Description

The TIGER/Line shapefiles and related database files (.dbf) are an extract of selected geographic and cartographic information from the U.S. Census Bureau's Master Address File / Topologically Integrated Geographic Encoding and Referencing (MAF/TIGER) Database (MTDB). The MTDB represents a seamless national file with no overlaps or gaps between parts, however, each TIGER/Line shapefile is designed to stand alone as an independent data set, or they can be combined to cover the entire nation. Census tracts are small, relatively permanent statistical subdivisions of a county or equivalent entity, and were defined by local participants as part of the 2020 Census Participant Statistical Areas Program. The Census Bureau delineated the census tracts in situations where no local participant existed or where all the potential participants declined to participate. The primary purpose of census tracts is to provide a stable set of geographic units for the presentation of census data and comparison back to previous decennial censuses. Census tracts generally have a population size between 1,200 and 8,000 people, with an optimum size of 4,000 people. When first delineated, census tracts were designed to be homogeneous with respect to population characteristics, economic status, and living conditions. The spatial size of census tracts varies widely depending on the density of settlement. Physical changes in street patterns caused by highway construction, new development, and so forth, may require boundary revisions. In addition, census tracts occasionally are split due to population growth, or combined as a result of substantial population decline. Census tract boundaries generally follow visible and identifiable features. They may follow legal boundaries such as minor civil division (MCD) or incorporated place boundaries in some States and situations to allow for census tract-to-governmental unit relationships where the governmental boundaries tend to remain unchanged between censuses. State and county boundaries always are census tract boundaries in the standard census geographic hierarchy. In a few rare instances, a census tract may consist of noncontiguous areas. These noncontiguous areas may occur where the census tracts are coextensive with all or parts of legal entities that are themselves noncontiguous. For the 2010 Census and beyond, the census tract code range of 9400 through 9499 was enforced for census tracts that include a majority American Indian population according to Census 2000 data and/or their area was primarily covered by federally recognized American Indian reservations and/or off-reservation trust lands; the code range 9800 through 9899 was enforced for those census tracts that contained little or no population and represented a relatively large special land use area such as a National Park, military installation, or a business/industrial park; and the code range 9900 through 9998 was enforced for those census tracts that contained only water area, no land area.

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