Ecosystem Stress, Recovery, and Restoration
Coastal wetland ecosystems can easily become stressed when hydrology is restricted by features such as a road or berm. While signs of vegetation stress are often evident, widespread vegetation mortality may not occur until additional disturbances such as a hurricane push the ecosystem over an ecological threshold. With time, natural recovery can often occur following a disturbance. Monitoring following disturbances helps us understand the factors influencing natural recovery. If altered hydrology prevents natural recovery, restoration efforts can facilitate and enhance recovery or create new habitat.
Coastal wetland restoration typically involves improving water flow, removing invasive species, sculpting the ground to the appropriate elevations for a wetland, or planting native vegetation. Restoration for oyster reefs involves providing hard substrates such as shells, limestone aggregate, or concrete for oyster settlement. The ultimate success of these restored habitats depends on a number of factors such as neighboring development, proliferation of invasive species, sea-level rise, and erosion. Restored habitats are monitored by identifying plant species and tracking changes in their ground or canopy coverage over time. Monitoring restored oyster reefs is completed by counting the density of live oysters on the artificial substrate. These monitoring projects evaluate the long-term efficacy of habitat restoration and the environmental factors impacting recovery. Lessons learned from monitoring help the design of future restoration projects to improve their ability to withstand the effects of climate change (such as more intense storms, rising sea level, and ocean acidification).