RAPID proposal: Impact of storm surge on coastal forest demography in response to repeated hurricane disturbances

Clemson University, Clemson SC

Investigators

Abstract

Large infrequent disturbances, such as hurricanes, significantly alter coastal forests through damaging winds and salt water carried with the storm surge. Depending on the frequency of the hurricanes and concurrent extent of the wind damage and salt water intrusion, coastal forests can be significantly damaged and may transition into salt water marsh. With a more variable climate system, hurricane return times will decrease and projected increasing sea level rise will enhance the opportunity for salt intrusion. Current understanding of hurricane effects is based largely on the effects of a single hurricane; few studies exist that document effects of repeated storms in one location or that separate the effects of storm surge from wind. In October 2016 Hurricane Matthew hit the South Carolina coast in largely in the same area affected by Hurricane Hugo in 1989, thus providing an opportunity to study multiple hurricane impacts on the same coastal forests. Hurricane Matthew differed in intensity and areas inundated with salt water. The project will introduce newer remote sensing capabilities to expand the studies to understand the short term and long term impacts on structure and functioning of the affected forests and at larger landscape and regional scales. This project's timely field assessments of wind damage, salt stress, soil chemistry, tree functioning, and tree establishment coupled with the remote sensing will test theoretical predictions and advance understanding of large infrequent disturbances on coastal forests. Large infrequent disturbances may structure forest ecosystem responses for very long periods of time and may trigger threshold responses that cause multiple paths of ecosystem response or even shifts in complete ecosystem structure and function. Much of the theory devoted to hurricane disturbance effects on coastal forest ecosystems arises from the study of single hurricanes or immediate response following the hurricane. Empirical tests and data are needed to evaluate multiple hurricanes across short and long time and site to regional space scales to fully understand the recovery and trajectories of change. This project leverages data and research sites from a long-term field study of coastal ecosystems to examine the consequences of the Hurricane Hugo on the recovery from wind throw and salt stress. The new studies will examine how wind damage and the salt intrusion from Hurricane Matthew affected soil processes, forest mortality and succession, forest functioning, and invasion of non-native species in response to differential hurricane disturbance. The remote sensing will assess forest structure, stress, phenology, and plant traits across the marsh/forest landscape and at multiple study areas along the coast of South Carolina. This work will provide critical tests of disturbance theory, succession, ecosystem structure and function across multiple space and time scales.