Affiliation:
1. Department of Landscape Architecture and Environmental Planning University of California Berkeley CA USA
2. Department of Landscape Architecture University of Washington Seattle WA USA
3. U.S. Geological Survey Western Ecological Research Center Oakhurst CA USA
4. U.S. Geological Survey Eastern Ecological Science Center Laurel MD USA
5. Department of Civil Engineering University of Texas at Arlington Arlington TX USA
6. Department of Civil and Environmental Engineering University of California Berkeley CA USA
Abstract
AbstractWith sea level rise threatening coastal development, decision‐makers are beginning to act by modifying shorelines. Previous research has shown that hardening or softening shorelines may change the tidal range under future sea level rise. Tidal range can also be changed by natural factors. Coastal marshes, which humans increasingly depend on for shoreline protection, are ecologically sensitive to tidal range. Therefore, it is critical to examine how changes in tidal range could influence marsh processes. A marsh accretion model was used to investigate the ecological response of a San Francisco Bay, California, USA marsh to multiple tidal range scenarios and sea level rise from 2010 to 2100. The scenarios include a baseline scenario with no shoreline modifications in the estuary, a shoreline hardening scenario that amplifies the tidal range, and 14 tidal range scenarios as a sensitivity analysis that span tidal amplification and reduction of the baseline scenario. The modeling results expose key tradeoffs to consider when planning for sea level rise. Compared to the baseline, the hardening scenario shows minor differences. However, further tidal amplification prolongs marsh survival but decreases Sarcocornia pacifica cover, an important species for certain threatened wildlife and an effective attenuator of wave energy. Conversely, tidal reduction precipitates marsh drowning but shows gains in Sarcocornia pacifica cover. These mixed impacts of tidal amplification and reduction shown by the model indicate potential tradeoffs in relation to marsh survival, habitat characteristics, and shoreline protection. This study suggests the need for a cross‐sectoral, regional approach to sea level rise adaptation.
Funder
National Science Foundation
University of California Berkeley
Publisher
American Geophysical Union (AGU)
Subject
Earth and Planetary Sciences (miscellaneous),General Environmental Science