Forest ThreatNet

Hurricanes are one of the most significant threats to coastal plain forest ecosystems and urban communities of the southeastern United States. Hurricanes alter water balances, causing extensive flooding, biogeochemical cycle disruption, water quality degradation, saltwater intrusion, and increased nutrient sedimentation loss in coastal watersheds. Recent research focused on Hurricane Michael highlights local impacts on watershed hydrology and recovery processes since 2018. 

In 2018 Hurricane Michael slammed into the US Gulf coast, a catastrophic event that impacted the Florida panhandle, southwestern Georgia, and southeastern Alabama causing billions of dollars in damage. To understand hurricane impacts on coastal watersheds, Forest Service scientists focused on the Chipola River basin, an area with mixed land uses across more than two thousand square kilometers. The study employed high resolution remote sensing technology, USGS streamflow data, and eco-hydrological modeling tools to assess hydrological impacts of Hurricane Michael in this large coastal plain landscape. Findings suggest that streamflow did not change appreciably during the first two years following the storm at the whole-basin scale, because only a fraction of the gauged watershed lost substantial tree cover. However, hydrological modeling coupled with remote sensing suggested that several sub‐watersheds with the highest decreases in vegetation due to hurricane damage significantly increased their monthly streamflow in 2019. These modeled streamflow changes subsided by the second growing season when vegetation recovered. Overall, this study suggests that changes in vegetation cover after Hurricane Michael did not have lasting hydrological impacts on water yield, and the hydrology of coastal watersheds may be more resilient to hurricane disturbances than previously thought.