Rising sea levels expose coastal forests to increasing amounts of salt water. In the same manner that a human cannot hydrate from seawater, trees cannot survive either, said Putz. You get disruption of biochemical processes. While sea levels have gone through periods of rise and fall over the years, the development of homes and farms along the coastline impede forests from growing anew on higher ground further inland. And the developers i.e. humans are most likely to blame for the global warming that has sped up the process of sea level rise in recent years.
Researchers note the death of trees in a coastal forest due to sea level rise.
They then tagged and counted all the trees and seedlings and monitored groundwater salinity and tidal flooding. Over the next three years, they returned to the sites periodically to note changes to the tree populations and correlate them with measurements of tidal flooding and changes in groundwater salinity. Despite the relatively short duration of the study, many trees died by the end of the field research. The researchers also found that even when older trees and palms survived they often failed to produce new seedlings, effectively making them the last generation of trees on the once densely forested islands. The study shows how sea level rise threatens coastal forests around the world where the forests are sandwiched between the ocean on one side and residential areas or farms on the other, said Putz.