2000 Submerged Aquatic Vegetation (SAV) in the Chesapeake Bay and coastal bays of Maryland and Virginia

Metadata:

• Identification_Information
• Data_Quality_Information
• Spatial_Data_Organization_Information
• Spatial_Reference_Information
• Entity_and_Attribute_Information
• Distribution_Information
• Metadata_Reference_Information

Identification_Information:

Citation:

Citation_Information:

Originator: Virginia Institute of Marine Science

Publication_Date: February 2001

Title:

2000 Submerged Aquatic Vegetation (SAV) in the Chesapeake Bay and coastal bays of Maryland and Virginia

Geospatial_Data_Presentation_Form: vector digital data

Publication_Information:

Publication_Place: Gloucester Point, Virginia

Publisher: Virginia Institute of Marine Science

Online_Linkage: <http://science.nature.nps.gov/nrdata>

Description:

Abstract:

These data set shows submerged aquatic vegetation in the Chesapeake Bay and the coastal bays in Maryland and Virginia in 2000. The 2000 Chesapeake Bay SAV Coverage was mapped from 1:24,000 black and white aerial photography to access water quality in the Bay. Each area of SAV was interpeted from the rectified photography and classified into one of four density classes by the percentage of cover.

Purpose:

The annual SAV aerial photographic monitoring program provides a comprehensive and accurate measure of change in SAV relative abundance that has been used to link improving water quality to increases in bay living resources.

Supplemental_Information: There is also SAV bed data for several other years available.

Time_Period_of_Content:

Time_Period_Information:

Range_of_Dates/Times:

Beginning_Date: 2000526

Ending_Date: 20001025

Currentness_Reference: ground condition

Status:

Progress: Complete

Maintenance_and_Update_Frequency: None planned

Spatial_Domain:

Bounding_Coordinates:

West_Bounding_Coordinate: -77.586875

East_Bounding_Coordinate: -74.999616

North_Bounding_Coordinate: 39.756832

South_Bounding_Coordinate: 36.478672

Keywords:

Theme:

Theme_Keyword_Thesaurus: National Park Service Theme Category Thesaurus

Theme_Keyword: Vegetation

Theme_Keyword: Plants

Theme_Keyword: Biology

Theme_Keyword: Water

Theme:

Theme_Keyword_Thesaurus: ISO 19115 Topic Category

Theme_Keyword: biota

Theme:

Theme_Keyword_Thesaurus: Assateague Island National Seashore Keyword Thesaurus

Theme_Keyword: vegetation

Theme_Keyword: plants

Theme_Keyword: aquatic

Theme_Keyword: SAV

Place:

Place_Keyword_Thesaurus: National Park System Unit Name Thesaurus

Place_Keyword: Assateague Island National Seashore

Place:

Place_Keyword_Thesaurus: National Park System Unit Code Thesaurus

Place_Keyword: ASIS

Place:

Place_Keyword_Thesaurus: Geographic Names Information System

Place_Keyword: North America

Place_Keyword: Maryland

Place_Keyword: Virginia

Place_Keyword: Chesapeake Bay

Access_Constraints: None

Use_Constraints: None.

Point_of_Contact:

Contact_Information:

Contact_Organization_Primary:

Contact_Organization:

Contact_Phone: 804/684-7088 Contact_email: savadmin@vims.edu Virginia Institute of Marine Science

Contact_Position: Data Administrator

Contact_Address:

Address_Type: mailing and physical address

Address: P.O.Box 1346

City: Gloucester Point

State_or_Province: Virginia

Postal_Code: 23062

Country: United States

Contact_Voice_Telephone: 804-684-7000

Contact_Facsimile_Telephone: 804-684-7097

Contact_Electronic_Mail_Address: savadmin@vims.edu

Hours_of_Service: 8:00am-4:30pm

Data_Set_Credit: SAV Mapping Lab, Virginia Institute of Marine Science

Native_Data_Set_Environment:

Microsoft Windows XP Version 5.1 (Build 2600) Service Pack 2; ESRI ArcCatalog 9.1.0.722

Cross_Reference:

Citation_Information:

Originator: Virginia Marine Science

Publication_Date: 2001

Publication_Time: Unknown

Title:

Metadata for 2000 Submerged Aquatic Vegetation (SAV) in the Chesapeake Bay and coastal bays of Maryland and Virginia

Geospatial_Data_Presentation_Form: vector digital data

Data_Quality_Information:

Attribute_Accuracy:

Attribute_Accuracy_Report:

The density attribute for all beds has been reviewed by an experienced photo-interpreter for correctness and consistency with analysis for prior years.

Logical_Consistency_Report:

The coverage contains full ArcInfo polygon topology. There are no unlabeled polygons, no intersections, no unattached lines and all lines have both left and right polygons identified.

Completeness_Report:

The dataset contains all SAV areas that were identified from the areas flown. Some areas that are presumed to contain no SAV were not flown. Some small beds, particularly along narrow tributaries may not have been distinguishable on the aerial photography.

Positional_Accuracy:

Horizontal_Positional_Accuracy:

Horizontal_Positional_Accuracy_Report:

Horizontal positional accuracy is based upon the use of USGS source quadrangles which are compiled to meet National Map Accuracy Standards (NMAS). The aerial photographs were manually overlaid on mylar USGS base material during the photo interpretation process. The mylars were then digitized within 24 meters of the interperted line.

Vertical_Positional_Accuracy:

Vertical_Positional_Accuracy_Report: unknown

Lineage:

Process_Step:

Process_Description:

Identification and delineation of SAV beds by photointerpretation utilized all available information including: knowledge of aquatic grass signatures on film, distribution of SAV in 2000 from aerial photography, 2000 ground survey information, and aerial site surveys. USGS 7.5 minute quadrangle maps (1:24,00 scale) printed by the Mid-Continent Mapping Center of the National Cartigraphic Information Center on stable transparent mylar were used as base maps. Distortion-free, identical copies of these base maps were made at the same scale on stable transparent mylar using a contact diazo process. SAV beds from the 2000 aerial photographs were then mapped onto these diazo mylar copies of USGS 7.5 minute quadrangles. Delineation of each SAV bed was facilitated by superimposing the photographic print with the appropriate diazo mylar quadrangle on a light table. SAV bed boundaries were then traced directly onto the mylar quadrangle with a pencil. Where minor scale differences were evident between a photograph and a quadrangle, or where significant shoreline erosion or accretion had occurred since USGS publication of the map, either a best fit was obtained or shoreline changes were noted on the quadrangle. In addition to delineating SAV bed boundaries, an estimate of SAV density within each bed was made by visually comparing each bed to an enlarged Crown Density Scale similar to those developed for estimating forest tree crown cover from aerial photography. Bed density was categorized into one of four classes based on a subjective comparison with the density scale. These were: 1, very sparse (<10% coverage); 2, sparse (10-40%); 3, moderate (40-70%); or 4, dense (70-100%). Either the entire bed or subsections within the bed were assigned a bed density number (1 to 4) corresponding to the above density classes. Some beds were subsectioned to delineate where variation in SAV density ocurred. Additionally, each distinct SAV unit (bed or bed subsection) was assigned an identifying two letter designation unique to its map. Subsections were futher identified as contiguous beds by the addition of two letters unique to that sequence. These contiguous bed identifications aid the tracking and analysis of single natural bed units that were subsectioned due to variation in SAV density. Coupled with the appropriate SAV map number and year of photography, these two letter designations uniquely identify each SAV bed in the data base.

Process_Date: 20010228

Process_Contact:

Contact_Information:

Contact_Organization_Primary:

Contact_Organization: Virginia Institute of Marine Science

Contact_Position: SAV Data Administrator

Contact_Address:

Address_Type: mailing and physical address

Address: P.O. Box 1346

City: Gloucester Point

State_or_Province: Virginia

Postal_Code: 23062

Country: United States

Contact_Voice_Telephone: 804-684-7000

Contact_Facsimile_Telephone: 804-684-7097

Contact_Electronic_Mail_Address: savadmin@vims.edu

Hours_of_Service: 8:00am-4:30pm

Process_Step:

Process_Description:

The perimeters of all SAV beds mapped from the aerial photography onto the mylar copies were digitized in ArcInfo, using an Altek Model 41 tablet, with a resolution of .001inches (.00254 cm) and an accuracy of .005 inches (.0127cm). The beds for each quadrangle were digitized in a primary ArcInfo coverage, and, as a quality assurance check, in a secondary ArcInfo coverage. These coverages were then overlaid digitally. If the area that differed between the two copies was more than 1 hectare and made up more than 2% of the bed or was more than 0.1 hectare and made up more than 10% of the bed, the bed was flagged for additional review. The primary coverage was then plotted at an exact scale of 1:24,000 on translucent plotter paper and overlaid on the original mylar for visual checking of all beds, with additional emphasis on beds flagged by the overlay step. In instances where the digitized SAV bed boundaries did not correspond to within 0.5 mm of the original, the bed was re-digitized. The bed-by-bed comparison was useful in identifying registration errors or instances where SAV beds were incorrectly labelled, thus eliminating coding errors. After all quadrangles were digitized, the resulting digital data was combined to form a single data set for the entireBay. The quadrangle borders were then scanned (edgematched) to ensure that the SAV polygons were consistent. Inconsistencies were resolved by checking the mylar maps and re-interpreting the photography if necessary.

Process_Date: 20010402

Process_Contact:

Contact_Information:

Contact_Organization_Primary:

Contact_Organization: Virginia Institute of Marine Science

Contact_Position: SAV Data Administrator

Contact_Address:

Address_Type: mailing and physical address

Address: P.O.Box 1346

City: Gloucester Point

State_or_Province: Virginia

Postal_Code: 23062

Country: United States

Contact_Voice_Telephone: 804-684-7000

Contact_Facsimile_Telephone: 804-684-7097

Contact_Electronic_Mail_Address: savadmin@vims.edu

Hours_of_Service: 8:00am-4:30pm

Process_Step:

Process_Description:

The bay segments were overlayed on the dataset by VIMS staff, dividing any beds that fell into multiple segments.

Process_Date: 2001

Process_Contact:

Contact_Information:

Contact_Organization_Primary:

Contact_Organization: Virginia Institute of Marine Science

Contact_Position: SAV Data Administrator

Contact_Address:

Address_Type: mailing and physical address

Address: P.O. Box 1346

City: Gloucester Point

State_or_Province: Virginia

Postal_Code: 23062

Country: United States

Contact_Voice_Telephone: 804-684-7000

Contact_Facsimile_Telephone: 804-684-7097

Contact_Electronic_Mail_Address: savadmin@vims.edu

Hours_of_Service: 8:00-4:30pm

Process_Step:

Process_Description:

The state boundaries were overlayed on the dataset by VIMS staff, dividing any beds that fell into multiple states.

Process_Date: 2001

Process_Contact:

Contact_Information:

Contact_Organization_Primary:

Contact_Organization: Virginia Institute of Marine Science

Contact_Position: SAV Data Administrator

Contact_Address:

Address_Type: mailing and physical address

Address: P.O. Box 1346

City: Gloucester Point

State_or_Province: Maryland

Postal_Code: 23062

Country: United States

Contact_Voice_Telephone: 804-684-7000

Contact_Facsimile_Telephone: 804-684-7097

Contact_Electronic_Mail_Address: savadmin@vims.edu

Hours_of_Service: 8:00am-4:30pm

Spatial_Data_Organization_Information:

Direct_Spatial_Reference_Method: Vector

Point_and_Vector_Object_Information:

SDTS_Terms_Description:

SDTS_Point_and_Vector_Object_Type: G-polygon

Point_and_Vector_Object_Count: 2573

Spatial_Reference_Information:

Horizontal_Coordinate_System_Definition:

Planar:

Grid_Coordinate_System:

Grid_Coordinate_System_Name: Universal Transverse Mercator

Universal_Transverse_Mercator:

UTM_Zone_Number: 18

Transverse_Mercator:

Scale_Factor_at_Central_Meridian: 0.999600

Longitude_of_Central_Meridian: -75.000000

Latitude_of_Projection_Origin: 0.000000

False_Easting: 500000.000000

False_Northing: 0.000000

Planar_Coordinate_Information:

Planar_Coordinate_Encoding_Method: coordinate pair

Coordinate_Representation:

Abscissa_Resolution: 0.000512

Ordinate_Resolution: 0.000512

Planar_Distance_Units: meters

Geodetic_Model:

Horizontal_Datum_Name: North American Datum of 1983

Ellipsoid_Name: Geodetic Reference System 80

Semi-major_Axis: 6378137.000000

Denominator_of_Flattening_Ratio: 298.257222

Entity_and_Attribute_Information:

Detailed_Description:

Entity_Type:

Entity_Type_Label: beds00Copy

Entity_Type_Definition:

2000 Submerged Aquatic Vegetation in the Chesapeake Bay and Coastal Bays of Maryland and Virginia

Entity_Type_Definition_Source: ASIS

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: AREA

Attribute_Definition: Area of feature in sqaure meters

Attribute_Definition_Source: VIMS

Attribute_Domain_Values:

Range_Domain:

Range_Domain_Minimum: 0.040000

Range_Domain_Maximum: 34776471091.814

Attribute_Units_of_Measure: square meters

Attribute:

Attribute_Label: ZONE

Attribute_Definition: Bay zone which contains the SAV bed

Attribute_Definition_Source: VIMS

Attribute_Domain_Values:

Enumerated_Domain:

Enumerated_Domain_Value: 1

Enumerated_Domain_Value_Definition: Upper Bay

Enumerated_Domain_Value_Definition_Source: VIMS

Attribute_Domain_Values:

Enumerated_Domain:

Enumerated_Domain_Value: 2

Enumerated_Domain_Value_Definition: Middle Bay

Enumerated_Domain_Value_Definition_Source: VIMS

Attribute_Domain_Values:

Enumerated_Domain:

Enumerated_Domain_Value: 3

Enumerated_Domain_Value_Definition: Lower Bay

Enumerated_Domain_Value_Definition_Source: VIMS

Attribute_Domain_Values:

Enumerated_Domain:

Enumerated_Domain_Value: 4

Enumerated_Domain_Value_Definition: Delmarva Peninsula Coastal Bays

Enumerated_Domain_Value_Definition_Source: VIMS

Attribute:

Attribute_Label: PERIMETER

Attribute_Definition: perimeter of featrues in meters

Attribute_Definition_Source: VIMS

Attribute_Domain_Values:

Range_Domain:

Range_Domain_Minimum: 1.857000

Range_Domain_Maximum: 6016306.694000

Attribute_Units_of_Measure: meters

Attribute:

Attribute_Label: BEDID

Attribute_Definition: Two-letter SAV bed identifier

Attribute_Definition_Source: VIMS

Attribute_Domain_Values:

Range_Domain:

Range_Domain_Minimum: AA

Range_Domain_Maximum: ZZ

Attribute:

Attribute_Label: DENSITY

Attribute_Definition: SAV density classification

Attribute_Definition_Source: VIMS

Attribute_Domain_Values:

Enumerated_Domain:

Enumerated_Domain_Value: 0

Enumerated_Domain_Value_Definition: No SAV

Enumerated_Domain_Value_Definition_Source: VIMS

Attribute_Domain_Values:

Enumerated_Domain:

Enumerated_Domain_Value: 1

Enumerated_Domain_Value_Definition: 0 - 10% coverage (very sparse)

Enumerated_Domain_Value_Definition_Source: VIMS

Attribute_Domain_Values:

Enumerated_Domain:

Enumerated_Domain_Value: 2

Enumerated_Domain_Value_Definition: 10 - 40 % cover (sparse)

Enumerated_Domain_Value_Definition_Source: VIMS

Attribute_Domain_Values:

Enumerated_Domain:

Enumerated_Domain_Value: 3

Enumerated_Domain_Value_Definition: 40 - 70% cover (moderate)

Enumerated_Domain_Value_Definition_Source: VIMS

Attribute_Domain_Values:

Enumerated_Domain:

Enumerated_Domain_Value: 4

Enumerated_Domain_Value_Definition: 70 - 100% cover (dense)

Enumerated_Domain_Value_Definition_Source: VIMS

Attribute:

Attribute_Label: CONTIGBED

Attribute_Definition:

Two letter identifier for a larger, multiple- density bed of which this is a portion

Attribute_Definition_Source: VIMS

Attribute_Domain_Values:

Range_Domain:

Range_Domain_Minimum: AA

Range_Domain_Maximum: ZZ

Attribute:

Attribute_Label: QUADID

Attribute_Definition: 2001 Distribution of SAV in the Chesapeake Bay.

Attribute_Definition_Source: VIMS

Attribute_Domain_Values:

Range_Domain:

Range_Domain_Minimum: 1

Range_Domain_Maximum: 231

Attribute:

Attribute_Label: CBPSEG

Attribute_Definition: Chesapeake Bay Program segment which contains the SAV bed

Attribute_Definition_Source: VIMS

Attribute_Domain_Values:

Unrepresentable_Domain:

Chesapeake Bay Program Segment abbreviations ("CHIPH" has been added to identify Chincoteague Bay)

Attribute:

Attribute_Label: BEDS00_

Attribute_Definition: unknown

Attribute_Definition_Source: ASIS

Attribute:

Attribute_Label: STATE

Attribute_Definition: U.S. State which contains SAV bed

Attribute_Definition_Source: VIMS

Attribute_Domain_Values:

Unrepresentable_Domain: MD= Maryland DC= Washington D.C. VA= Virginia

Attribute:

Attribute_Label: BEDS00_ID

Attribute_Definition: unknown

Attribute_Definition_Source: ASIS

Attribute:

Attribute_Label: BEDLABEL

Attribute_Definition: unknwon

Attribute_Definition_Source: ASIS

Attribute:

Attribute_Label: SURVEYED

Attribute_Definition: Indicates whether the polygon was covered by the annual survey

Attribute_Definition_Source: VIMS

Attribute_Domain_Values:

Enumerated_Domain:

Enumerated_Domain_Value: T

Enumerated_Domain_Value_Definition: included in the area surveyed

Enumerated_Domain_Value_Definition_Source: VIMS

Attribute_Domain_Values:

Enumerated_Domain:

Enumerated_Domain_Value: F

Enumerated_Domain_Value_Definition: not included in the area surveyed

Enumerated_Domain_Value_Definition_Source: VIMS

Attribute_Domain_Values:

Enumerated_Domain:

Enumerated_Domain_Value: P

Enumerated_Domain_Value_Definition: Area was mapped at less than maximum biomass

Enumerated_Domain_Value_Definition_Source: VIMS

Overview_Description:

Entity_and_Attribute_Overview:

The SAV polygon attributes are used to identify each SAV bed or portion of an SAV bed, classify it by density and assign into a geographic or political region.

Distribution_Information:

Distributor:

Contact_Information:

Contact_Organization_Primary:

Contact_Organization: Virginia Institute of Marine Science

Contact_Position: SAV Data Administrator

Contact_Address:

Address_Type: Gloucester Point, Virginia 23062mailing and physical address

Address: P.O. Box 1346

City: Gloucester Point

State_or_Province: Virginia

Postal_Code: 23062

Country: United States

Contact_Voice_Telephone:

Contact_Phone: 804/684-7088 Contact_Email: savadmin@vims.edu 804-684-7000

Contact_Facsimile_Telephone: 804-684-7097

Contact_Electronic_Mail_Address: savadmin@vims.edu

Hours_of_Service: 8:00am-4:30pm

Resource_Description: 2000 Chesapeake Bay SAV Coverage

Distribution_Liability:

The National Park Service shall not be held liable for improper or incorrect use of the data described and/or contained herein. These data and related graphics (i.e. GIF or JPG format files) are not legal documents and are not intended to be used as such. The information contained in these data is dynamic and may change over time. The data are not better than the original sources from which they were derived. It is the responsibility of the data user to use the data appropriately and consistent within the limitations of geospatial data in general and these data in particular. The related graphics are intended to aid the data user in acquiring relevant data; it is not appropriate to use the related graphics as data. The National Park Service gives no warranty, expressed or implied, as to the accuracy, reliability, or completeness of these data. It is strongly recommended that these data are directly acquired from an NPS server and not indirectly through other sources which may have changed the data in some way. Although these data have been processed successfully on computer systems at the National Park Service, no warranty expressed or implied is made regarding the utility of the data on other systems for general or scientific purposes, nor shall the act of distribution constitute any such warranty. This disclaimer applies both to individual use of the data and aggregate use with other data.

Standard_Order_Process:

Digital_Form:

Digital_Transfer_Information:

Format_Name: shp

Transfer_Size: 10.080

Fees: None

Metadata_Reference_Information:

Metadata_Date: 20060809

Metadata_Contact:

Contact_Information:

Contact_Organization_Primary:

Contact_Organization: Virginia Institute of Marine Science

Contact_Person: REQUIRED: The person responsible for the metadata information.

Contact_Position: SAV Data Administrator

Contact_Address:

Address_Type: mailing and physical address

Address: Gloucester Point, Virginia 23062P.O Box 1346

City: Gloucester Point

State_or_Province: Virginia

Postal_Code: 23062

Country: United States

Contact_Voice_Telephone: 804-684-7000

Contact_Facsimile_Telephone:

Contact_Phone: 804/684-7088 Contact_Email: savadmin@vims.edu 804-684-7097

Contact_Electronic_Mail_Address: savadmin@vims.edu

Hours_of_Service: 8:00am-4:30pm

Metadata_Standard_Name: FGDC Content Standards for Digital Geospatial Metadata

Metadata_Standard_Version: FGDC-STD-001-1998

Metadata_Time_Convention: local time

Metadata_Access_Constraints: none

Metadata_Use_Constraints: none

Metadata_Extensions:

Online_Linkage: <http://nrdata.nps.gov/profiles/nps_profiles.xml>

Profile_Name: NPS Metadata Profile

Metadata_Extensions:

Online_Linkage: <http://www.esri.com/metadata/esriprof80.html>

Profile_Name: ESRI Metadata Profile