Coastal forested wetlands support many endemic
species, sequester substantial carbon stocks, and
have been reduced in extent due to historic drainage
and agricultural expansion. Many of these
unique coastal ecosystems have been drained,
while those that remain are now threatened by
saltwater intrusion and sea level rise in hydrologically
modified coastal landscapes. Several recent
studies have documented rapid and accelerating
losses of coastal forested wetlands in small areas of
the Atlantic and Gulf coasts of North America, but
the full extent of loss across North America’s
Coastal Plain (NACP) has not been quantified. We
used classified satellite imagery to document a net
loss of 13,682 km2 (8%) of forested coastal
wetlands across the NACP between 1996 and 2016.
Most forests transitioned to scrub-shrub (53%) and
marsh habitats (24%). Even within protected areas,
we measured substantial rates of wetland deforestation
and significant fragmentation of forested wetland
habitats. Variation in the rate of sea level rise, the
number of tropical storm landings, and the average
elevation of coastal watersheds explained about 78%
of the variation in coastal wetland deforestation extent
along the south Atlantic and Gulf Coasts. The rate
of coastal forest loss within the NACP (684 km2/y)
exceeds the recent estimate of global losses of coastal
mangroves (210 km2/y). At the current rate of
deforestation, in the absence of widespread protection
or restoration efforts, coastal forested wetlands may
not persist into the next century.
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This content will become publicly available on June 1, 2025
Vulnerability of Wetlands Due to Projected Sea-Level Rise in the Coastal Plains of the South and Southeast United States
Coastal wetlands are vulnerable to accelerated sea-level rise, yet knowledge about their extent and distribution is often limited. We developed a land cover classification of wetlands in the coastal plains of the southern United States along the Gulf of Mexico (Texas, Louisiana, Mississippi, Alabama, and Florida) using 6161 very-high (2 m per pixel) resolution WorldView-2 and WorldView-3 satellite images from 2012 to 2015. Area extent estimations were obtained for the following vegetated classes: marsh, scrub, grass, forested upland, and forested wetland, located in elevation brackets between 0 and 10 m above sea level at 0.1 m intervals. Sea-level trends were estimated for each coastal state using tide gauge data collected over the period 1983–2021 and projected for 2100 using the trend estimated over that period. These trends were considered conservative, as sea level rise in the region accelerated between 2010 and 2021. Estimated losses in vegetation area due to sea level rise by 2100 are projected to be at least 12,587 km2, of which 3224 km2 would be coastal wetlands. Louisiana is expected to suffer the largest losses in vegetation (80%) and coastal wetlands (75%) by 2100. Such high-resolution coastal mapping products help to guide adaptation plans in the region, including planning for wetland conservation and coastal development.
more » « less- Award ID(s):
- 1728913
- PAR ID:
- 10529340
- Editor(s):
- NA
- Publisher / Repository:
- NA
- Date Published:
- Journal Name:
- Remote Sensing
- Edition / Version:
- NA
- Volume:
- 16
- Issue:
- 12
- ISSN:
- 2072-4292
- Page Range / eLocation ID:
- 2052
- Subject(s) / Keyword(s):
- Wetlands remote sensing sea level rise
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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