Accomack County, Virginia : Tidal Marsh Inventory 2016

Metadata also available as

Metadata:

Identification_Information:
Citation:
Citation_Information:
Originator:
Sharon Killeen, Comprehensive Coastal Inventory Program, Virginia Institute of Marine Science, GIS Programmer/Analyst
Publication_Date: 20160930
Title: Accomack County, Virginia : Tidal Marsh Inventory 2016
Geospatial_Data_Presentation_Form: vector digital data
Online_Linkage:
<http://ccrm.vims.edu/gis_data_maps/static_maps/gis/tmi_updated.html>
Description:
Abstract:
The Virginia Institute of Marine Science published the first Tidal marsh Inventories for Virginia in the 1970s. Using high resolution color infra-red imagery from 2013 a new Tidal Marsh Inventory has been developed for Accomack County. Marsh boundaries were generated using heads-up digitizing techniques at a scale of 1:1,000. Each marsh polygon was classified by morphologic type: fringe, extensive, embayed, or marsh island. Marshes were ground-truthed in the field where a community type index was assigned to each marsh based on plant community make-up. Each marsh was also coded with a marsh number which corresponds to the original 1970s delineation. This will provide an opportunity to review changes that have occurred in the marshes over time.
Purpose:
To maintain and update an inventory of the distribution of tidal marshes for the Commonwealth of Virginia.
Supplemental_Information:
There are five shapefiles assocaited with Accomack County Inventory database: AccomackCo_lubc_2016,AccomackCo_astru_2016, Accomack Co_sstru_2016, AccomackCo_tm_2016, and AccomackCo_beaches_2016. AccomackCo_lubc_2016 (land use and bank cover for Accomack County) is a linear shapefile containing data about land use, tree fringe, bank height, bank cover, bank stability and beach status along the shoreline. AccomackCo_sstru_2016 ( Accomack County shoreline structures) is a linear shapefile delineating hard structures in place at the shoreline (bulkhead, dilapidated bulkhead, riprap, wharf, unconentional, debris, marina < 50 slips, marina > 50 slips, jetty, marsh toe revetment, groinfield and breakwaters). AccomackCo_astru_2016 (Accomack County access structures) is a point shapefile with locations of docks, dilapidated docks, boathouses, and private and public boat ramps. AccomackCo_tm_2016 (Accomack County tidal marshes) shows the location, size, species and type of tidal marshes in Accomack County. AccomackCo_beaches_2016 is a linear shapefile showing the presence of beaches on the shoreline of Accomack County. The attributes of these five shapefiles are explained in the Entity and Attribute Information section below.
Time_Period_of_Content:
Time_Period_Information:
Range_of_Dates/Times:
Beginning_Date: 20160531
Ending_Date: 20160609
Currentness_Reference: Unknown
Status:
Progress: Complete
Maintenance_and_Update_Frequency: Unknown
Spatial_Domain:
Bounding_Coordinates:
West_Bounding_Coordinate: -76.045690
East_Bounding_Coordinate: -75.246969
North_Bounding_Coordinate: 38.026784
South_Bounding_Coordinate: 37.450528
Keywords:
Theme:
Theme_Keyword_Thesaurus: None
Theme_Keyword:
Tidal Marsh, Wetland Plant Identification, Wetland Community Type
Theme:
Theme_Keyword_Thesaurus: ISO 19115 Topic Categories
Theme_Keyword: biota
Theme_Keyword: boundaries
Theme_Keyword: environment
Place:
Place_Keyword_Thesaurus: None
Place_Keyword:
Pocomoke River, Pocomoke Sound,Messongo Creek,Cattail Creek, Guilford Creek, The Thorofare, Chesconessex Creek,Onancock Creek,Pungoteague Creek,Nandua Creek,Occohannock Creek, Chesapeake Bay
Access_Constraints: None
Use_Constraints: None
Point_of_Contact:
Contact_Information:
Contact_Organization_Primary:
Contact_Organization: Center for Coastal Resources Management
Contact_Person: Julie Bradshaw
Contact_Address:
Address_Type: mailing and physical
Address: Virginia Institute of Marine Science
Address: PO Box 1346 | Rt. 1208 Greate Rd.
City: Gloucester Point
State_or_Province: Virginia
Postal_Code: 23062
Contact_Voice_Telephone: 804-684-7894
Contact_Electronic_Mail_Address: julieb@vims.edu
Native_Data_Set_Environment:
Microsoft Windows 7 Version 6.1 (Build 7601) Service Pack 1; Esri ArcGIS 10.4.0.5524
Data_Quality_Information:
Lineage:
Process_Step:
Process_Description:
A shoreline for Accomack County was created using the 2013 VBMP imagery as a backdrop and using ArcGis version 10.2. Using this as a baseline the shoreline inventory was remotely generated using two sources: Google Earth 2015 imagery , and 2013 high resolution imagery available through Bing Maps and 2013 high resolution imagery available from the Virginia Base Mapping Program (VBMP).
Process_Date: 20160130
Process_Step:
Process_Description:
Tidal marshes were delineated from 2013 VBMP imagery using onscreen digitizing techniques at a scale of 1:1,000. Bing and Google Earth online imagery was used to provide additional interpretive information to improve the accuracy of marsh boundaries. Marsh polygons were coded by shape and physiographic setting based on a classification system applied in the first Prince George County Tidal Marsh Inventory (in 1989). Quality assurance and control measures were performed prior to generation of maps for fieldwork.
Process_Date: 20160331
Process_Step:
Process_Description:
VBMP imagery, with the marsh polygon layer overlay, was printed for use in field surveys of the marshes.
Process_Date: 20160429
Process_Step:
Process_Description:
Field collection of marsh data was performed primarily from a small shallow-draft vessel, navigating at slow speeds parallel to the shoreline. Surveys extended as far upstream as depth and field conditions allowed. Some additional data collection was performed by land where marshes were easily accessible from public lands. During surveys, marsh boundaries were verified, and wetland plant species observed within each marsh polygon were recorded along with relative cover estimates to determine marsh community types.
Process_Date: 20160630
Process_Step:
Process_Description:
Corrections were made to the digital data back at the lab using ArcGis Version 10.0.
Process_Date: 20160831
Spatial_Data_Organization_Information:
Direct_Spatial_Reference_Method: Vector
Point_and_Vector_Object_Information:
SDTS_Terms_Description:
SDTS_Point_and_Vector_Object_Type: GT-polygon composed of chains
Point_and_Vector_Object_Count: 9133
Spatial_Reference_Information:
Horizontal_Coordinate_System_Definition:
Planar:
Map_Projection:
Map_Projection_Name: NAD 1983 UTM Zone 18N
Transverse_Mercator:
Scale_Factor_at_Central_Meridian: 0.9996
Longitude_of_Central_Meridian: -75.0
Latitude_of_Projection_Origin: 0.0
False_Easting: 500000.0
False_Northing: 0.0
Planar_Coordinate_Information:
Planar_Coordinate_Encoding_Method: coordinate pair
Coordinate_Representation:
Abscissa_Resolution: 0.000000002220024164500956
Ordinate_Resolution: 0.000000002220024164500956
Planar_Distance_Units: meter
Geodetic_Model:
Horizontal_Datum_Name: D North American 1983
Ellipsoid_Name: GRS 1980
Semi-major_Axis: 6378137.0
Denominator_of_Flattening_Ratio: 298.257222101
Entity_and_Attribute_Information:
Detailed_Description:
Entity_Type:
Entity_Type_Label: Accomack_TMI_2016
Attribute:
Attribute_Label: FID
Attribute_Definition: Internal feature number.
Attribute_Definition_Source: Esri
Attribute_Domain_Values:
Unrepresentable_Domain:
Sequential unique whole numbers that are automatically generated.
Attribute:
Attribute_Label: Shape
Attribute_Definition: Feature geometry.
Attribute_Definition_Source: Esri
Attribute_Domain_Values:
Unrepresentable_Domain: Coordinates defining the features.
Attribute:
Attribute_Label: MarshType
Attribute_Definition:
Description of polygon (i.e. Marsh, MarshIsland, NoMarsh_Forest, NoMarsh_Sand, NoMarsh_ScrubShrub, Water).
Attribute_Definition_Source: Processor
Attribute:
Attribute_Label: Number
Attribute_Definition: a unique number for the marsh within Prince George County
Attribute:
Attribute_Label: Field
Attribute_Definition:
Field observation: Yes: Observed in the field; No: Could not see in the field
Attribute_Definition_Source: Field Personnel
Attribute:
Attribute_Label: MarshNo
Attribute_Definition: a unique number for the marsh within Prince George County
Attribute:
Attribute_Label: CmtyType
Attribute_Definition:
Tidal Marsh Inventories – Community Types & Field Codes Type I: Predominately Saltmarsh Cordgrass / low marsh Type II: Predominately Saltmeadow / high marsh Type III: Predominately Black Needlerush Type IV: Predominately Saltbush Type V: Predominately Big Cordgrass Type VI: Predominately Cattail Type VII: Predominately Arrow Arum - Pickerelweed Type VIII: Predominately Reed Grass Type IX: Predominately Yellow Pond Lily Type X: Predominately Saltwort Type XI: Freshwater mix - no dominant species Type XII: Brackish mix - no dominant specie s
Attribute_Definition_Source: Field Personnel
Attribute:
Attribute_Label: Reedgrass
Attribute_Definition:
Percent of Reedgrass (Phragmites) observed: D = Marsh 51-100% Phragmites; X = Marsh 1-50% Phragmites ;T = Marsh < 1% Phragmites
Attribute_Definition_Source: Field Personnel
Attribute:
Attribute_Label: PrcntPhrag
Attribute_Definition: Percent cover of Phragmites australis observed in marsh.
Attribute_Definition_Source: Field Personnel
Attribute:
Attribute_Label: FieldDate
Attribute_Definition: Date of field observation
Attribute_Definition_Source: Field Personnel
Attribute:
Attribute_Label: Observer
Attribute_Definition: Field personnel making the observations.
Attribute_Definition_Source: Field Personnel
Attribute:
Attribute_Label: MrshNum
Attribute:
Attribute_Label: CommunType
Attribute_Definition:
Tidal Marsh Inventories – Community Types : Type I: Predominately Saltmarsh Cordgrass / low marsh Type II: Predominately Saltmeadow / high marsh Type III: Predominately Black Needlerush Type IV: Predominately Saltbush Type V: Predominately Big Cordgrass Type VI: Predominately Cattail Type VII: Predominately Arrow Arum - Pickerelweed Type VIII: Predominately Reed Grass Type IX: Predominately Yellow Pond Lily Type X: Predominately Saltwort Type XI: Freshwater mix - no dominant species Type XII: Brackish mix - no dominant species
Attribute_Definition_Source: Tidal Marsh Inventories – Community Types & Field Codes
Attribute:
Attribute_Label: Dominant_P
Attribute_Definition: Dominant plant species
Attribute_Definition_Source: Field Personnel
Attribute:
Attribute_Label: Acres
Attribute_Definition:
Area of wetland polygon in acres (GIS calculated in UTM zone 18)
Attribute_Definition_Source: Processor
Attribute:
Attribute_Label: County
Attribute_Definition: Virginia Jurisdiction
Attribute_Definition_Source: Processor
Attribute:
Attribute_Label: PhragPres
Attribute_Definition:
Indicates the presence of Phragmites australis as < 50% or >50% of marsh polygon.
Attribute_Definition_Source: Processor
Metadata_Reference_Information:
Metadata_Date: 20160929
Metadata_Contact:
Contact_Information:
Contact_Organization_Primary:
Contact_Organization:
Comprehensive Coastal Inventory Program, Virginia Institute of Marine Science
Contact_Person: Sharon Killeen
Contact_Position: GIS Programmer/Analyst
Contact_Address:
Address_Type: mailing and physical
Address: 1375 Greate Road, P.O.Box 1346
City: Gloucester Point
State_or_Province: Virginia
Postal_Code: 23062
Country: US
Contact_Voice_Telephone: 804-684-7534
Contact_Facsimile_Telephone: 804-684-7179
Contact_Electronic_Mail_Address: sharon@vims.edu
Metadata_Standard_Name: FGDC Content Standard for Digital Geospatial Metadata
Metadata_Standard_Version: FGDC-STD-001-1998
Metadata_Time_Convention: local time
Generated by mp version 2.9.12 on Thu Sep 29 15:36:56 2016