20250617 06452300 FALSE 20071114 16220000 20071114 16220000 1.0 ESRI ArcCatalog 9.2.0.1324 en The Natural Landscape Assessment (NLA), a component of the Virginia Conservation Lands Needs Assessment (VCLNA), is a landscape-scale GIS analysis for identifying, prioritizing, and linking natural habitats in Virginia. Using land cover data derived from satellite imagery, the NLA identifies unfragmented natural habitats called cores, large patches of natural land cover (mainly upland forests and forested wetlands statewide, but also marshes, beaches, and dunes in the coastal plain) with at least 100 acres of interior conditions. Large, medium, and small cores have been identified (see definitions in attribute section), along with a smaller feature type called "habitat fragments" that may be important in the more urban localities. Cores provide habitat for a wide ranges of species, from forest interior-dependent to habitat-generalist species, as well as species that utilize marsh, dune, and beach habitats. Cores also provide benefits in terms of open space, recreation, water quality (including drinking water protection), and carbon sequestration, along with the associated economic benefits of these functions. The NLA generates fundamental ecological data layer for land and natural resources conservation in Virginia. Virginia Department of Conservation and Recreation 20061103 VaNLA_Cores_Lite vector digital data withheld ground condition circa 2000 In work As needed -84.230112 -75.042339 39.761333 36.161913 -405723.342837 382316.655337 27860.746649 417470.749444 Virginia Natural Landscape Assessment VaNLA REQUIRED: Restrictions and legal prerequisites for accessing the data set. REQUIRED: Restrictions and legal prerequisites for using the data set after access is granted. Shapefile Joseph T. Weber Department of Conservation and Recreation Natural Heritage GIS Projects Manager/Conservation Biologist (804) 371-2545 (804) 371-2674 joseph.weber@dcr.virginia.gov 7:30 AM - 4:15 PM ESRI ArcCatalog 9.2.0.1324 VaNLA_Cores_Lite -405723.342837 382316.655337 417470.749444 27860.746649 1 -84.230112 -75.042339 39.761333 36.161913 1 en FGDC Content Standards for Digital Geospatial Metadata FGDC-STD-001-1998 local time Joseph T. Weber Department of Conservation and Recreation REQUIRED: The mailing and/or physical address for the organization or individual. REQUIRED: The city of the address. REQUIRED: The state or province of the address. REQUIRED: The ZIP or other postal code of the address. (804) 371-2545 Natural Heritage GIS Projects Manager/Conservation Biologist (804) 371-2674 joseph.weber@dcr.virginia.gov 7:30 AM - 4:15 PM 20071114 http://www.esri.com/metadata/esriprof80.html ESRI Metadata Profile ISO 19115 Geographic Information - Metadata DIS_ESRI1.0 dataset Downloadable Data 128.194 128.194 Although all data referred to in this documentation have been used by VADCR, no warranty, expressed or implied, is made by VADCR or the original data sources as to the accuracy of the data. The act of distribution shall not constitute any such warranty, and no responsibility is assumed by VADCR in the use of these data. Users must assume responsibility to determine appropriate use of these data. VaNLA feature boundaries are not to be used for legal definitions of these areas. Please contact the proper agency or organization with questions concerning ancillary data sets used in, but not created by, the VaNLA. The re-distribution of this dataset for profit is prohibited. 002 withheld Local Area Network 128.194 Shapefile Vector Simple Polygon FALSE 34135 FALSE FALSE G-polygon 34135 GCS_North_American_1983 NAD_1983_Lambert_Conformal_Conic coordinate pair meters 0.000000 0.000000 Lambert Conformal Conic 37.000000 39.500000 -79.500000 36.000000 0.000000 0.000000 North American Datum of 1983 Geodetic Reference System 80 6378137.000000 298.257222 NAD_1983_Lambert_Conformal_Conic 34135 VaNLA_Cores_Lite Feature Class 34135 FID FID OID 4 0 0 This field contains the Internal Feature Number, a unique sequential number that is automatically generated by ArcGIS 9.1 software. ESRI Sequential unique whole numbers that are automatically generated. Shape Shape Geometry 0 0 0 This field contains the feature geometry, the coordinates defining the features. ESRI Coordinates defining the features. COREID COREID Number 9 This field contains a unique numeric identifier for each VANLA Core or Habitat Fragment. TYPE TYPE String 254 This field identifies the type of VANLA feature. LC Large Core: a core area with at least 10,000 acres of interior cover MC Medium Core: a core area with 1,000 - 9,999 acres of interior cover SC Small Core: a core area with 100 to 999 acres of interior cover HF Habitat Fragment: a patch of natural land cover with 10 to 99 acres of interior cover EO_COUNT EO_COUNT Number 19 11 This field contains the number of Natural Heritage Element Occurrences per VANLA Core or Habitat Fragment. These occurrences exclude records without dates, with dates prior to 1981, or with poor spatial precision (minutes or general precision). TIER1EHACR TIER1EHACR Number 19 11 This field contains the acreage of potential and confirmed habitats for Tier 1 species, the species of greatest conservation need in Virginia, per VANLA Core or Habitat Fragment. The source of these data is the Virginia Wildlife Action Plan that was developed by the Virginia Department of Game and Inland Fisheries. SRMAX SRMAX Number 19 11 This field contains the maximum value of potential species richness values of vertebrates and lepidopterans per VANLA Core or Habitat Fragment based of potential distribution maps developed by the Virginia GAP. TOTALACRES TOTALACRES Number 19 11 This field contains the total acreage of each VANLA Core or Habitat Fragment. DEPTHINTER DEPTHINTER Number 19 11 This field contains the depth of interior of each VANLA Core or Habitat Fragment. This value represents the maximum distance (meters) from all edges that can be achieved within a core or habitat fragment. This parameter is useful for selecting and modeling cores that provide more protection for interior species. THREAT THREAT Number 19 11 This field indicates the threat if not conserved of each VANLA Core or Habitat Fragment. The values indicate the potential land use change from the current use to an urban or suburban use. Values range from 1, lowest potential of conversion, to 8, greatest potential of conversion. The source of these data is the Virginia Vulnerability Model, VCLNA. DRINKACRE DRINKACRE Number 19 11 This field contains the acreage of high priority groundwater and surface water protection zones per VANLA Core or Habitat Fragment. The source of these data is the Virginia Department of Health Office of Drinking Water. UMNWIACRES UMNWIACRES Number 19 11 This field contains the acreage of unmodified wetlands per VANLA Core or Habitat Fragment. Unmodified wetlands are based on National Wetlands Inventory data from which farmed, diked, ditched, and otherwise modified wetlands were removed. Beaver impoundments, which are a natural form of modification, were left in the unmodified wetlands layer. UMNWIPERC UMNWIPERC Number 19 11 This field contains the percent area of unmodified wetlands per VANLA Core or Habitat Fragment. Unmodified wetlands are based on National Wetlands Inventory data from which farmed, diked, ditched, and otherwise modified wetlands were removed. Beaver impoundments, which are a natural form of modification, were left in the unmodified wetlands layer. PercConsVa PercConsVa Number 15 1 This field contains the percentage of each core or habitat fragment that is already conserved according to DCR's Conservation Lands Database (as of 21 August 2006). SitesIndex SitesIndex Number 16 6 This field contains the Conservation Sites Index, which resulted from summing the products of B-rank factors and B-rank weights. The B-rank factors resulted from dividing conservation site and core intersections by the total area of intersecting conservation sites with the same B-rank. The weights were 50, 40, 30, 20, and 10 for B1, B2, B3, B4, and B5 ranked conservation sites, respectively. SCUIndex SCUIndex Number 19 11 This field contains the Stream Conservation Units (SCU) and Threatened and Endangered (T&E) Waters Index, which resulted from summing the products of B-rank factors and B-rank weights. The T&E Waters were buffered to the same width (5 meters) as SCUs and assigned B-ranks before they were merged with the SCUs. The B-rank factors resulted from dividing intersections of the T&E-SCU features and cores by the total area of intersecting T&E-SCU features with the same B-rank. The weights were 50, 40, 30, 20, and 10 for B1, B2, B3, B4, and B5 ranked T&E-SCU features, respectively. The T&E Waters layer was developed by Virginia Department of Game and Inland Fisheries. ECM ECM Number 19 11 This field contains scores from the Ecological Composite Model used to assess ecological integrity. Definition of Ecological Integrity: Maintaining vital natural landscapes is essential for basic ecosystem services such as cleaning our air and filtering our water. Natural lands also harbor thousands of species of animals and plants and contain libraries of genetic information from which we derive new foods, materials, and medicinal compounds. These parts of the landscape also provide us with recreational opportunities and open space resources. But these qualities are represented differently across the cores and habitat fragments that constitute the natural landscape. To assess their unique values, each core and habitat fragment has been assigned an ECOLOGICAL INTEGRITY score that rates the relative contribution of that area to the ecosystem service values above. In general, larger, more biologically diverse areas are given higher scores. Scores are enhanced if the core or habitat fragment is part of a larger complex of natural lands. Scores also are increased for those cores and habitat fragments that contribute to water quality enhancement. EI_Class EI_Class Number 4 1 Outstanding 2 Very High 3 High 4 Moderate 5 General This field represents the ecological integrity scores from the ECM summarized in 5 classes. 20071114 The study area includes the entire commonwealth of Virginia and a 20-mile buffer around the state. This large buffer was selected to prevent truncation of cores and corridors that cross the state boundary and to facilitate edge matching to similar projects conducted in adjacent states. The Virginia Department of Conservation and Recreation contracted with the University of Maryland (UMD) to develop a land cover layer for the entire state from Landsat Thematic Mapper satellite imagery. The final product, named RESAC 2000, was derived from imagery dating from 1999 to 2001. RESAC 2000 has 21 classes, nine of which represent natural land covers: Barren, Deciduous Forests, Evergreen Forests, Mixed Forests, Deciduous Wooded Wetlands, Evergreen Wooded Wetlands, Emergent Herbaceous Wetlands, Mixed Wetlands, and Natural Grass. An overall thematic accuracy of 90% was reported for this layer. The resolution of this layer is 30-meters, square. The RESAC 2000 layer had only a very small buffer around the state, ergo additional imagery was acquired for coverage of the entire study area. Imagery from the Chesapeake Bay Resource Lands Assessment (also developed by UMD), National Land Cover Data (NLCD) 2001, and one piece of NLCD 1992 were merged to RESAC 2000. The NLCD classifications were cross-walked to match RESAC 2000 and all images were projected to Lambert Conformal Conic before merging. Despite the high reported accuracy of RESAC 2000, there were several important classification errors that needed to be corrected. An accuracy assessment utilizing a five-percent random sample of the Natural Grass class revealed that it almost always represented hayfield or pasture, therefore this class was reclassified to agriculture. There were also maritime grass communities and marshes that were misclassified as agriculture. The marshes were corrected using National Wetlands Inventory (NWI) data, after excluding farmed wetlands, and the maritime grasses were reclassified to a new class of the same name using high-resolution photography to confirm the occurrences were not agriculture. Beaches and dune areas were in the Barren class of RESAC 2000. In order to extract these important natural land covers, undeveloped beaches and dunes were digitized from high-resolution aerial photography dated 2002 (Virginia Base Mapping Program) and the resulting polygons were used to reclassify these areas to a new class named Undeveloped Beaches/Dunes. The resulting layer is known as VANLA Land Cover. The VANLA Land Cover was used to develop the VANLA cores, which are defined for this analysis as patches of natural cover containing at least 100 acres of interior cover. Interior cover begins 100 meters inward from the patch edge. This 100-meters buffer constitutes the abiotic transition zone following the "three-tree-height" rule (Harris 1984), since fully mature forests in Virginia reach maximum height around 33 meters. The first step in the core development process was to assemble a fragmentation layer that included spatial data for powerlines, pipelines, railroads, and roads. This layer was used to fragment the VANLA Land Cover, thus making a better approximation of the fragmentation in the landscape. Anthropogenic land covers were excluded from the analysis at this point by extracting from the fragmented land cover layer only the following classes and then classifying them as natural cover: Deciduous Forests, Evergreen Forests, Mixed forests, Deciduous Wooded Wetlands, Evergreen Wooded Wetlands, Emergent Herbaceous Wetlands, Mixed Wetlands, Undeveloped Beaches/Dunes, and Maritime Grasses. One pixel width of near-shore open water was added back from the fragmented land cover to the natural cover layer. This prevented narrow stretches of open water less than 60 meters across (two pixel widths) from splitting a core into two or more smaller patches. The interior areas of the patches in the natural cover layer were identified by using distance analysis to calculate the 100-meter abiotic transition zone of each patch. Interior areas greater than or equal to 10 acres were then identified; all patches not meeting this criterion were excluded from further analysis. The abiotic transition zone was added back to the remaining interior areas. These patches were then classified into Large Cores if they had at least 10,000 acres of interior cover, Medium Cores if they had 1,000 to 9,999 acres of interior cover, Small Cores if they had 100 to 999 acres of interior cover, and Habitat Fragments if they had 10 to 99 acres of interior cover. The Habitat Fragments feature type resulted from a pilot study for the VANLA completed in 2004 (Weber & Carter-Lovejoy) which revealed that the 100-acres minimum interior size for cores was too restrictive for urban and some suburban localities. These features may contain natural heritage resources and have utility for recreation, open space, and storm water management, but they are too small or narrow to provide many of the other benefits of cores. Analyses were performed to add many prioritization attributes to the cores and habitat fragments layer. Definitions and justifications for each of these prioritization attributes can be found in the attributes section of these metadata. 20061107 15183400 Dataset copied. withheld 20061214 16040100 Dataset copied. withheld 20070110 14472200 Dataset copied. withheld 20070315 16061800 Dataset copied. withheld 20070406 16303000 Dataset copied. withheld 20070502 20163000 Dataset copied. withheld 20070503 19182700 Dataset copied. withheld 20070507 08044300 Dataset copied. withheld 20070509 15304400 Dataset copied. withheld 20070622 14164000 Dataset copied. withheld 20070625 13281500 Dataset copied. withheld 20070627 14581300 Dataset copied. withheld 20091012 12132800 Dataset copied. withheld 20120917 08332000 Dataset copied. withheld 20131031 12315200