Coastal Massachusetts Submerged Aquatic Bed

Abstract:

The Coastal Change Analysis Program (C-CAP) at NOAA Coastal Services Center partnered with The Massachusetts Department of Environmental Protection Wetlands Conservancy Program (DEP-WCP) and Office of Coastal Zone Management (CZM) to produce a digital coverage of submerged aquatic vegetation, primarily eelgrass (Zostera marina) along the Atlantic coast of Massachusetts. Conventional color metric aerial photography at a scale of 1:20,000 was acquired form 1994-1996 according to stringent parameters detailed in the C-CAP protocol (www.csc.noaa.gov/ccap). The photography was photointerpreted by DEP-WCP using a biocular stereoscope (Cartographic Engineering Modular Stereoscope Model SB 190). Polygons of eelgrass were delineated onto acetate overlays affixed to each photograph. Extensive fieldwork was conducted to develop signatures and gather surface level data where the presence or extent of habitat was not apparent from the photography.  An underwater video camera was utilized in this effort.  The aerial photos, with the interpreted acetates attached, were scanned using a photogramteric quality scanner (AGFA Horizon Plus) at a resolution of 600 dpi resulting in a pixel resolution of .85 meters. The resulting image file was rectified (bilinear 2nd order) by C-CAP to 1 meter black and white and color digital orthophotos supplied by CZM. The polygon delineation from the rectified image was then digitized onscreen. In addition, a point file was generated based on field-verified sites as well as all occurrences of widgeon grass (Ruppia maritima) and algae.  The rectification and digitization was completed utilizing the ERDAS Imagine software package. The benthic data is classified according to the System for Classification of Habitats in Estuarine and Marine Environments (SCHEME).  This system is fully described in "Development of a System for Classification of Habitats in Estuarine and Marine Environments (SCHEME) for Florida, Report to U.S. EPA - Gulf of Mexico Program, Florida Fish and Wildlife Conservation Commission, Florida Marine Research Institute. Review Draft 12/04/02."  The polygon vector coverage was accuracy assessed by C-CAP and DEP-WCP in July 1997 and September 1998. The assessment was based on random points generated within the polygon boundaries. Navigation to each point in the field was accomplished using real time differential GPS. The underwater video camera was used to verify the presence of the mapped feature at the random point. The accuracy of the mapped grass was 85.4 % (175 of 205 sites mapped correct).

Purpose:

Provide a baseline digital map of submerged aquatic vegetation resources for coastal management applications.

Supplemental_Information:

A total of six covergaes were produced in this project.
There are two sets of three files. The first set is projected using the Massachusetts mainland state plane projection and covers the entire Atlatntic shoreline. This set contains a SAV polygon coverage, a field-verified point coverage, and a point coverage containing all occurances of Ruppia maritime and algae. The second set is projected using the Massachusetts islands state plan projection and covers Martha's Vineyard and Nantucket. This set contains a SAV polygon coverage, a field-verified point coverage, and a point coverage containing all occurances of Ruppia maritime and algae.
Aerial Photo Information Project
Areas
Nantucket Acquisition
Dates (YYYYMMDD): 19931006
Photo Source: James W. Sewall Company
Mission ID: A5076
Scale: 1:20,000
Overlap/Sidelap: 80/40
Film Type: Aerochrome 2448
Filter Type/Number: clear
Camera Type: Zeiss RMK Top 15
Lens Type and Focal Length: 6"/153 mm
Image Format (23cm, etc.): 9"
Number of Rolls/Frames: Roll # 2097, 70 exposures
Martha's Vineyard, Elizabeth Islands and South Coast of
Cape Cod Acquisition
Dates (YYYYMMDD): 19940511/19940921/19950528
Photo Source: James W. Sewall Company
Mission ID: A 5223
Scale: 1:20,000
Overlap/Sidelap: 80/40
Film Type: Aerochrome 2448
Filter Type/Number: clear
Camera Type: Zeiss RMK Top 15
Lens Type and Focal Length: 6"/153 mm
Image Format (23cm, etc.): 9"
Number of Rolls/Frames Roll # 2224 & 2225, 517 exposures
Northern Coast of Cape Cod
Acquisition Dates (YYYYMMDD): 19950629/19950528/19960419
Photo Source: James W. Sewall Company
Mission ID: A5223
Scale: 1:20,000
Overlap/Sidelap: 80/40
Film Type: Aerochrome 2448
Filter Type/Number: clear
Camera Type: Zeiss RMK A 1.5/23 & Zeiss RMK Top 15
Lens Type and Focal Length: clear
Image Format (23cm, etc.): 9"
Number of Rolls/Frames: Roll # 2225 & 2226, 337 exposures
Boston Harbor and North Shore Acquisition
Dates (YYYYMMDD):19960718
Photo Source: James W. Sewall Company
Mission ID: A 5522
Scale: 1:20,000
Overlap/Sidelap: 80/40
Film Type: Aerochrome 2448
Filter Type/Number: clear
Camera Type: Zeiss RMK A 1.5/23 & Zeiss RMK Top 15
Lens Type and Focal Length: 6"/153 mm
Image Format (23cm, etc.): 9"
Number of Rolls/Frames: roll # 2243 & 2244, 388 exposures
Buzzards Bay and Mount Hope Bay
Acquisition Dates (YYYYMMDD): 19960507
Photo Source: James W. Sewall Company
Mission ID: A 5522
Scale: 1:20,000
Overlap/Sidelap: 80/40
Film Type: Aerochrome 2448
Filter Type/Number: clear
Camera Type: Zeiss RMK A 1.5/23 & Zeiss RMK Top 15
Lens Type and Focal Length: 6"/153 mm
Image Format (23cm, etc.): 9"
Number of Rolls/Frames: Roll # 2237 & 2240, 342 exposures

Attribute_Accuracy_Report:

Overall accuracy of 8 meters for line work. See abstract for attribute accuracy assessment methodology and results.

Entity_and_Attribute_Overview:

The benthic data is classified according to the System for
Classification of Habitats in Estuarine and Marine
Environments (SCHEME).  This system is fully described in
"Development of a System for Classification of Habitats in
Estuarine and Marine Environments (SCHEME) for Florida, Report
to U.S. EPA - Gulf of Mexico Program, Florida Fish and Wildlife
Conservation Commission, Florida Marine Research Institute.
Review Draft 12/04/02."