Coastal wetlands are barriers against flooding, though accosted by major storms, sea-level rise, and human development.
Researchers are studying those environments to better the nation's Earth system simulations.
Their work in the coastal marshes of Louisiana, Mangrove Swamps of Texas, and wetlands of Chesapeake Bay and Lake Erie is critical to understanding how these ecosystems respond when environmental stressors kick in.
A Closer Look at Louisiana's Coastline
A project underway, led by lead principal investigator Elizabeth Herndon of ORNL, is studying biogeochemical processes taking place along Louisiana's coastline.
Two contrasting sites were selected for this study: one in which a delta is growing due to river diversion and the other where land is sinking because of a sediment supply cutoff.
This study considers freshwater and seawater flooding in understanding interactions in these ecosystems between phosphate, iron, and manganese.
Herndon's team collects water and soil samples to track the impact of flooding and drainage on environmental parameters like pH, moisture, and redox conditions.
These are very important processes in the proper chemical transformations, for the ecosystem. Significantly enhanced predictive modeling capabilities will be gained from this work for decision-making and New Orleans' preparation for the future.
The rise in sea level, which causes the melting of ice and ice sheets, leads to the erosion of the coastline and the flooding of critical habitats such as wetlands and mangroves.
Warmer global temperatures alter the distribution of coastal species, wherein few migrants move to cooler regions whereas others face extinction.
The rising levels of atmospheric CO2 result in ocean acidification, prone to damage to marine life, especially those having calcium carbonate structures. Changed precipitation patterns alter salinity in coastal waters and disturb the sensitive balance of marine ecosystems.
In addition, rising intensities of weather events, such as hurricanes or cyclones, tend to cause extensive destruction to these habitats.
Last but not least, these valuable ecosystem services-one in the form of carbon sequestration and another in the form of storm protection-by coastal regions are compromised for both the environment and human communities dependent upon them.
These are challenges that identify the immediate need for workable conservation and management strategies that ensure the safeguarding of the ecosystems of coasts against the impacts of climate change.
This work from ORNL scientists shows well what proactive steps are being taken to understand and mitigate the impacts of climate change on coastal landscapes.
In addition, during its research, besides manifesting the present state of these ecosystems, it brings the future into focus to be better prepared and respond to challenges that are emerging concerning that.
