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Abstract
Polygons
This 2019 dataset consists of digital vector data describing the location, extent and species composition of submerged aquatic vegetation (SAV) in coastal Alabama, including Mississippi Sound, Mobile Bay, Mobile-Tensaw Delta, Mississippi Sound, Little Lagoon, Perdido Bay, and their communicating tributaries. The dataset includes a MrSID ortho mosaic produced from true-color digital aerial imagery acquired on July 26, 29, and 31 and August 1 and 2. ESRI polygon coverage of SAV was created in ArcGIS 10.7, using the MrSID as a base map. SAV distribution was concentrated in upper Mobile Bay and the lower Mobile-Tensaw Delta, Mississippi Sound, and the lower Perdido Bay area of southeast Baldwin County. Overall, there were 866 more acres mapped in 2019 compared to 2015, due mostly to a 469-ac increase in the Hurricane quadrangle, particularly areas around Gravine Island and Chuckfee Bay. There were 149 more acres mapped in the Chickasaw quad compared to 2015, due to expansion of SAV in the Duck Lake region. The Orange Beach Quadrangle had an increase of 74 acres, mostly due to expanded coverage in the area of St. John Bayou. Habitat categories were developed based on observation of the most prevalent species at field survey locations. Of the 37 habitat categories identified, most were mixtures of species occurring in oligohaline and freshwater systems.
Field Points
This 2019 data set consists of GPS point data documenting the location, species composition, and other habitat characteristics of submerged aquatic vegetation beds in coastal Alabama, including Mississippi Sound, Mobile Bay, Mobile-Tensaw Delta, Mississippi Sound, Little Lagoon, Perdido Bay, and their communicating tributaries. Field data were collected as part of a Tier 1 remote sensing investigation of SAV distribution using summer 2019 ortho imagery as a base map. Species identifications were made through in-situ observations or hand collected and identified in the field or laboratory. Depth (m) was measured with a graded sounding pole. Field surveys began in August 2019 and continued to mid-November, assessing a total of 643 field points. Additional locations were visited in the spring of 2020 to survey sites not inspected during 2019, or return to previously surveyed areas to collect additional data. Areas inspected in 2020 included East Fowl River, upper Dog River, upper Perdido Bay, and western Mississippi Sound. In total, field data were collected at 843 locations.
Purpose
DOI: 10.57778/04wy-0x83
Suggested Citation
Heck, K., Byron, D., & Barry A. Vittor and Associates, Inc. (2022). Alabama 2019 Submerged Aquatic Vegetation Polygons and Field points [Dataset]. Dauphin Island Sea Lab. https://doi.org/10.57778/04WY-0X83
Related Publication Citation
Attribution
This project was paid for [in part) with federal funding from the Gulf Coast Ecosystem Restoration Council under the Resources and Ecosystems Sustainability, Tourist Opportunities, and Revived Economies of the Gulf Coast States Act of 2012 (RESTORE Act). The statements, findings, conclusions, and recommendations are those of the author(s) and do not necessarily reflect the views of the Gulf Coast Ecosystem Restoration Council or Alabama Department of Conservation and Natural Resources.
