Mapping High Marsh Systems across the Northern Gulf of Mexico

Keywords: high marsh, irregularly flooded wetlands, Gulf of Mexico, salt pannes, remote sensing, satellite data, elevation data, vegetation data
Session Type: Virtual Poster Abstract
Day: Monday
Session Start / End Time: 2/28/2022 11:20 AM (Eastern Time (US & Canada)) - 2/28/2022 12:40 PM (Eastern Time (US & Canada))
Room: Virtual 33

Abstract

High marsh along the northern Gulf of Mexico coast provides important habitat for avian wildlife, such as the federally threatened Black Rail (Laterallus jamaicensis), and priority species including the Yellow Rail (Coturnicops noveboracensis) and Mottled Duck (Anas fulvigula). Consequently, there is an urgent need to delineate the distribution and quantify the areal coverage of high marsh along the northern Gulf of Mexico. Here, we present a two-step approach for mapping high marsh that integrates high-resolution elevation data, vegetation information, and satellite imagery. First, we used Monte Carlo simulations to incorporate elevation uncertainty and lidar-derived digital elevation models to create a probabilistic map of irregularly flooded wetlands. Next, validation and training data were collected in collaboration with land managers across the northern Gulf of Mexico coast. These data were combined with Sentinel-1 synthetic aperture radar imagery, multi-spectral satellite imagery from Sentinel-2, digital elevation models, and the previously mentioned probabilistic classification to generate a contemporary map of high marsh and salt pannes for the region. This product is the first regional map of these wetland systems across the northern Gulf coast and will provide a baseline for future marsh and avian monitoring efforts along the Gulf of Mexico.