eelgrass97

Identification Information

Citation Information

Originator	Seth Barker, Maine Department of Marine Resources (MEDMR)
Publication Date	20030701
Title	eelgrass97
Geospatial Data Presentation Form	vector digital data
Series Name	Maine GIS
Issue Identification	SDE server; Internet Data Catalog
Publication Place	Augusta ME
Publisher	Maine Office of Geographic Information Systems (MEGIS)
Other Citation Details	1:24000
Online Linkage	http://megis.maine.gov/catalog/
Beginning Date	1992
Beginning Time	Unknown
Ending Date	1997
Ending Time	Unknown

Abstract

eelgrass97 is a POLYGON coverage that represents Maine's eelgrass meadows, which form an important aquatic habitat for the state, suitable for mapping at 1:24,000 scale. These meadows provide shelter for juvenile fish, and invertebrates. In certain locations they also help stabilize unconsolidated sediments and shorelines. As a continuing project, sections of the coast have been flown and photographed using Kodak 2448 film at a scale of 1:12000. This photography has been supplemented in the Penobscot Bay region by 1992 flights using Kodak 2445 film. The Penobscot Bay flights were contracted by the Maine Department of Transportation and interpreted by Dr. Fred Short of University of New Hampshire. Areas in the present study were flown in the July to October period during 1993 to 1997. When possible, photography was at the time of extreme low tides, low wind velocity, good water clarity, and maximum biomass of eelgrass. These factors aid in the detection of the subtidal portion a bed. Transparencies from the 1993-1997 flights were oriented beneath and eelgrass bed locations compiled on stable-base manuscripts containing the coastline and other basemap features from the 1:24000 scale USGS topographic maps. Polygons delineating stands of eelgrass were digitized and coded using a four category scale of percent cover. Verification has been carried out by boat, on foot, and by plane. Though dense patches of eelgrass approximately 6 meters in diameter and less can be identified under good conditions, a conservative estimate of the minimum mapping unit is 150 square meters. This represents a stand of approximately 14 meters in diameter.

Purpose

Eelgrass beds along the Maine coast are being mapped in order to better understand the present day distribution and to aid in the identification of sensitive coastal areas for protection in the case of an oil spill.

Time Period of Content

Beginning Date	1992
Ending Date	1997
Currentness Reference	publication date

Status

Progress	Complete
Maintenance and Update Frequency	None planned

Bounding Coordinates

West Bounding Coordinate	-70.8225
East Bounding Coordinate	-66.97426
North Bounding Coordinate	45.10967
South Bounding Coordinate	43.05744

Keywords

Theme	oceans, biota, environment, economy (ISO Keyword Thesaurus)
Theme	habitat, eelgrass, submerged aquatic vegetation (SAV), fisheries (Maine GIS Thesaurus-Theme)
Place	Maine, United States, Gulf of Maine (Maine GIS Thesaurus-Place)
Stratum	biosphere, oceans (GCMD Parameter Keyword)

Use Constraints

Users must assume responsibility in determining the usability of this data for their purposes. Digital maps retain the accuracy of their source materials. The best use of data mapped at scales of 1:500,000 and 1:250,000 is in statewide planning and studies; at 1:100,000 in regional planning and studies; at 1:62,500 and 1:24,000 in detailed studies and local planning; and at 1:12,000 and 1:5,000 or larger scales in parcel level studies and detailed local planning. In the use of Maine GIS data, please check sources, scale, accuracy, currentness and other available information. Please confirm that you are using the correct copy of both data and metadata from the Maine GIS Data Catalog. Updates, corrections, and feedback, incorporated in the Maine GIS database are made in accordance with "Data Standards for Maine Geographic Information Systems", 2002, and coordinated by MEGIS.

Contact Organization

(MEDMR) Maine Department of Marine Resources

Contact Person

Seth Barker

Contact Position

GIS Specialist

Address Type

mailing address

Address

PO Box 8

City

West Boothbay Harbor

State or Province

Postal Code

04575

Country

USA

Contact Voice Telephone

(207) 633-9507

Contact Facsimile Telephone

(207) 633-9579

Contact Electronic Mail Address

seth.barker@maine.gov

Hours of Service

Monday through Friday 0800 - 1700 EST

Data Set Credit

Credit should always be given to the data source and/or originator when the data is transferred or printed.

Native Data Set Environment

(MEDMR) Maine Department of Marine Resources; Maine Office of Information Technology (OIT) Oracle 9i, Maine Office of Geographic Information Systems (MEGIS), Maine GIS SDE, Maine GIS Internet Data Catalog http://megis.maine.gov/catalog/

Attribute Accuracy Report

Thematic accuracy was checked using GPS controlled navigation to representative areas of the coastline. The vector polygon data was loaded into a field PC and displayed in ArcView software. A tracking software allowed the analyst to travel to specific points in the data with precision and to check the type of habitat in the field. Sample sites were selected based on their location and distribution along the coast. No empirical accuracy statistics were generated. Proof plots were checked against original manuscripts

Logical Consistency Report

Following interpretation and digitization, an Arc/Info format polygon coverage was BUILT. An editing process was also conducted to ensure proper closure and labeling.

Completeness Report

All eelgrass beds interpretable from aerial photography were mapped.

Horizontal Positional Accuracy Report

Approximate horizontal accuracy is 12 meters, assuming source data meets National Map Accuracy Standards.

Horizontal Positional Accuracy Value

Horizontal Positional Accuracy Explanation

Compilation base data meets National Map Accuracy Standards for 1:24,000 scale.

Citation Information

Originator	Maine Department of Transportation (MEDOT), Dr. Fred Short Univeristy of New Hampshire (UNH) (ed.), Seth Barker Maine Department of Marine Resources (MEDMR) (comp.)
Title	(KODAK2445)MEGRASSPHOTOS
Geospatial Data Presentation Form	remote-sensing image
Series Name	Eelgrass Mapping Project
Issue Identification	Photography Penobscot Bay
Publication Place	Augusta ME
Publisher	Maine Office of Geographic Information Systems (MEGIS)
[smcilnkh]	false
[smcisrcs]	12000
[smcisrcm]	filmstrip
Calendar Date	1992
Time of Day	Unknown
[smcisrcc]	ground condition

Source Scale Denominator

12000

Type of Source Media

filmstrip

Calendar Date

1992

Time of Day

Unknown

Source Currentness Reference

ground condition

Source Citation Abbreviation

kodak2445

Source Contribution

Eelgrass photography has been supplemented in the Penobscot Bay region by 1992 flights using Kodak 2445 film. The Penobscot Bay flights were contracted for by the MEDOT and interpreted by Dr. Fred Short of UNH.

Citation Information

Originator	Seth Barker Maine Department of Marine Resources (MEDMR)
Title	(KODAK2448)MEGRASSPHOTOS
Geospatial Data Presentation Form	remote-sensing image
Series Name	Eelgrass Mapping Project
Issue Identification	Photography
Publication Place	Augusta ME
Publisher	Maine Office of Geographic Information Systems (MEGIS)
[smcilnkh]	false
[smcisrcs]	12000
[smcisrcm]	filmstrip
Beginning Date	1993
Beginning Time	Unknown
Ending Date	1997
Ending Time	Unknown
[smcisrcc]	ground condition

Source Scale Denominator

12000

Type of Source Media

filmstrip

Beginning Date

1993

Beginning Time

Unknown

Ending Date

1997

Ending Time

Unknown

Source Currentness Reference

ground condition

Source Citation Abbreviation

kodak2448

Source Contribution

As a continuing eelgrass mapping project, sections of the coast have been flown and photographed using Kodak 2448 film at a scale of 1:12000.

Citation Information

Originator	U.S. Geological Survey (USGS)
Publication Date	multiple dates
Publication Time	Unknown
Title	(24k) USGS 1:24,000 scale quadrangles
Geospatial Data Presentation Form	map
Series Name	National Mapping Program Standard Series Topographic Maps
Issue Identification	USGS 7.5 Minute Map Series
Publication Place	Reston VA
Publisher	U.S. Geological Survey
Other Citation Details	24000 Publication date is unique to each quadrangle in the map series. Standard 7.5x7.5 minute quadrangles cover geographic areas of 49 to 71 square miles. 1 inch at map scale represents 2000 feet.
Online Linkage
Beginning Date	19480101
Beginning Time	Unknown
Ending Date	Present
Ending Time	Unknown
[smcisrcc]	publication date

Beginning Date

19480101

Beginning Time

Unknown

Ending Date

Present

Ending Time

Unknown

Source Currentness Reference

publication date

Source Citation Abbreviation

24k

Source Contribution

Eelgrass bed locations were compiled on stable-base manuscripts containing the coastline and other basemap features from the 24k USGS topographic maps.

Process Description

Photo-Interpretation- Duplicated film diapositives were interpreted monoscopically on a large-format light table. Submerged aquatic vegetation (SAV) habitat was annotated on acetate overlays attached to the film. The habitat was assigned to one (1) of four (4) density classes based on percent ground coverage by actual eelgrass. The photography was interpreted by a skilled analyst very familiar with the local environment. GPS controlled field work was used to develop signatures suitable for mapping.

Process Date

1997

Contact Organization

(MEDMR) Maine Department of Marine Resources

Contact Position

GIS Specialist

Address Type

mailing address

Address

PO Box 8

City

West Boothbay Harbor

State or Province

Postal Code

04575

Country

USA

Contact Voice Telephone

(207) 633-9507

Contact Facsimile Telephone

(207) 633-9579

Hours of Service

Monday through Friday 0800 - 1700 EST

Process Description

Data Vectorization- At the conclusion of the interpretation process, the diapositives with overlays attached were placed on the light table below mylar USGS 7.5 minute quads. The photos were manually fitted to the USGS map and the habitat polygons were transferred to the quad mylars. The annotated mylar was scanned and an automated vectorization software was used to capture the linework as ESRI vectors. These vectors were manually edited and a polygon coverage was built using ArcInfo software. The polygon coverage was then attributed according to the four SAV density classes.

Process Date

1997

Contact Organization

(MEDMR) Maine Department of Marine Resources

Contact Position

GIS Specialist

Address Type

mailing address

Address

PO Box 8

City

West Boothbay Harbor

State or Province

Postal Code

04575

Country

USA

Contact Voice Telephone

(207) 633-9507

Contact Facsimile Telephone

(207) 633-9579

Hours of Service

Monday through Friday 0800 - 1700 EST

Process Description

Aerial Photography Acquisition- Conventional color (Kodak Aerochrome 2448) film was acquired over the Maine coast at a nominal scale of 1:12,000. The coast was flown in an incremental fashion in 1993, 1994, 1995, 1996, and 1997. The film was flown according to the environmental parameters recommended in the C-CAP protocol. The mission specifications included 60% endlap and 30% sidelap for adjacent lines. A 153mm color-corrected lens and Wild RC10 camera were used to collect the imagery.

Process Date

1997

Contact Organization

(MEDMR) Maine Department of Marine Resources

Contact Position

GIS Specialist

Address Type

mailing address

Address

PO Box 8

City

West Boothbay Harbor

State or Province

Postal Code

04575

Country

USA

Contact Voice Telephone

(207) 633-9507

Contact Facsimile Telephone

(207) 633-9579

Hours of Service

Monday through Friday 0800 - 1700 EST

Cloud Cover

Direct Spatial Reference Method

Vector

SDTS Point and Vector Object Type

Area chain

Point and Vector Object Count

7519

[smcaptur]

false

Grid Coordinate System Name

UTM Zone Number

Scale Factor at Central Meridian

0.9996

Longitude of Central Meridian

-69

Latitude of Projection Origin

False Easting

500000

False Northing

Planar Coordinate Encoding Method

Abscissa Resolution

Ordinate Resolution

Horizontal Datum Name

North American Datum of 1983

Ellipsoid Name

Geodetic Reference System 80

Semi-major Axis

6378137

Denominator of Flattening Ratio

298.257

Entity Type Label

eelgrass97

Entity Type Definition

polygon feature class

Entity Type Definition Source

Environmental Systems Research Institute, Inc. (ESRI)

Attribute Label

ACRES

Attribute Definition

area of mapped eelgrass meadow in acres

Beginning Date of Attribute Values

Attribute Label

COVER

Attribute Definition

eelgrass percent cover

Attribute Definition Source

User Defined

Range Domain Minimum

Range Domain Maximum

Enumerated Domain Value

Enumerated Domain Value Definition

no submerged aquatic vegetation (SAV)

Enumerated Domain Value

Enumerated Domain Value Definition

0-10% cover (very sparse)

Enumerated Domain Value

Enumerated Domain Value Definition

10-40% cover (sparse)

Enumerated Domain Value

Enumerated Domain Value Definition

40-70% cover (moderate)

Enumerated Domain Value

Enumerated Domain Value Definition

70-100% cover (dense)

Enumerated Domain Value

Enumerated Domain Value Definition

uncoded

Beginning Date of Attribute Values

Attribute Label

HECTARES

Attribute Definition

area of mapped eelgrass meadow in hectares

Beginning Date of Attribute Values

Attribute Label

LOCATION

Attribute Definition

location in relation to low water

Attribute Definition Source

User Defined

Enumerated Domain Value

Enumerated Domain Value Definition

intertidal

Enumerated Domain Value

Enumerated Domain Value Definition

subtidal

Enumerated Domain Value

Enumerated Domain Value Definition

undetermined

Beginning Date of Attribute Values

Entity and Attribute Overview

eelgrass97 POLYGONS are attributed with percent of eelgrass COVER and LOCATION in relation to low water.

Entity and Attribute Detail Citation

The ArcView shapefile and ArcGIS geodatabase formats, commonly used for Maine GIS data, carry default identifiers and attributes that are software generated and/or important for internal recordkeeping. These are listed here to avoid repetition for every layer, and may not be repeated in the attribute descriptions and definitions of each layer. Common software generated identifiers and attributes in Maine GIS data include: FID (feature identifier), Shape (feature geometry), OBJECTID and SHAPE_lengt. In addition, most GIS formats will carry fields for PERIMETER, AREA and/or LENGTH according to feature geometry. These fields are typically available by default, with the units based on coordinate system or projection units of GIS data. Most GIS software packages also provide a means to calculate these values. It is important to test any columns containing PERIMETER, AREA or LENGTH values before using them for analysis purposes. These important values can be carried from format to format and become out-dated. Verify that the values are correct. Also, in your GIS software, please view the properties of data layers for the map units used to calculate these fields, and for the units set for display purposes.

Entity and Attribute Overview

eelgrass97 POLYGONS are attributed with percent of eelgrass COVER and LOCATION in relation to low water.

Entity and Attribute Detail Citation

Contact Organization

(MEGIS) Maine Office of Geographic Information Systems

Contact Person

GIS Coordinator

Contact Position

GIS Coordinator

Address Type

mailing address

Address

State House Station 174

City

Augusta

State or Province

Postal Code

04333-0174

Country

USA

Contact Voice Telephone

207 624-7700

Contact Facsimile Telephone

207 287-3842

Hours of Service

Monday through Friday 0800 - 1700 EST

Resource Description

http://megis.maine.gov/catalog/

Distribution Liability

Users must assume responsibility to determine the usability of this data for their purposes. Although these data have been processed successfully on a computer system at the Maine Office of Geographic Information Systems, no warranty expressed or implied is made by MEGIS regarding the utility of the data on any other system, nor shall the act of distribution constitute any such warranty. Neither the Maine Office of Geographic Information Systems, nor any of its contributors, is liable for misuse of the data, for damage, for transmission of viruses, or for computer contamination through the distribution of these data sets.

Format Name

ESRI Shapefile

Format Version Number

ARC Version 9.x

Format Specification

ArcView Shapefile Format

Format Information Content

MEGIS has made all vector layers, in the Maine GIS Internet Data Catalog, available in ESRI's ArcView shapefile format. A shapefile is a simple non-topological format that stores the geometry and attribute information for a set of geographic features as a set of vector (point, line, polygon) coordinates. Shapefiles draw quickly and directly in ArcView, ArcGIS, ArcExplorer. Shapefiles are a compatible data type for many other types of GIS software. Three files are fundamental to each shapefile: .shp stores the feature geometry (shape and location information); .shx stores the index of the feature geometry; .dbf a dBASE (TM) file stores the attribute information for the features. Other index files may be created to help speed analysis and query: these file formats are .sbn .sbx .ain .aix .fbn and .fbx. In addition you may find projection .prj, and metadata .xml, files associated with shapefiles.

File Decompression Technique

Data available from this website is in .zip compressed format. WinZip is a Windows based, PKZip-compatible compression utility. You will need a program like this to extract the data.

Network Resource Name

[accinstr]

These data are available to Internet browsers for download from the Maine GIS Internet Data Catalog - http://megis.maine.gov/catalog/Data available from this website is in .zip compressed format. WinZip is a Windows based, PKZip-compatible compression utility. You will need a program like this to extract the data.If you are not already a GIS user, free software for viewing these files is available from Environmental Systems Research Institute, Inc. (ESRI) - www.esri.com

[smdistty]

Fees

Data may be downloaded from Maine GIS Internet Data Catalog at no charge.

Turnaround

Data is available for immediate download from the Maine GIS Internet Data Catalog.

Technical Prerequisites

If you are not already a GIS user, free software for viewing these files is available from Environmental Systems Research Institute, Inc. (ESRI) http://www.esri.com/

Contact Organization

Maine Office of Geographic Information Systems

Contact Position

GIS Coordinator

Address Type

mailing address

Address

State House Station 174

City

Augusta

State or Province

Postal Code

04333-0174

Country

USA

Contact Voice Telephone

(207) 624-7700

Contact Facsimile Telephone

(207) 287-3842

Hours of Service

Monday through Friday 0800 - 1700 EST

Distribution Liability

Users must assume responsibility to determine the usability of this data for their purposes.

Format Name

ARCSDE

Format Version Number

ArcSDE 9.x

Format Information Content

Oracle 9i

[accinstr]

Please contact the Maine Office of GIS (MEGIS) for access instructions.

[smdistty]

Fees

Access is available through Maine's wide area network; WAN users may contact the Maine Office of Information Technology, Maine Office of Geographic Information Systems (MEGIS) for a login.

Metadata Reference Information

Metadata Date

19990511

Metadata Review Date

20100114

Metadata Future Review Date

Metadata Contact

Contact Organization	(MEDMR) Maine Department of Marine Resources
Contact Position	GIS Specialist
Address Type	mailing address
Address	PO Box 8
City	West Boothbay Harbor
State or Province	ME
Postal Code	04575
Country	USA
Contact Voice Telephone	(207) 633-9507
Contact Facsimile Telephone	(207) 633-9579
Hours of Service	Monday through Friday 0800 - 1700 EST

Metadata Standard Name

FGDC CSDGM

Metadata Standard Version

FGDC-STD-001-1998

Metadata Access Constraints

none

Metadata Use Constraints

none