Authors: Anthony Campbell*, University of Rhode Island, Yeqiao Wang, University of Rhode Island
Topics: Remote Sensing, Coastal and Marine, Natural Resources
Keywords: Wetlands, Object-based, Change detection
Session Type: Paper
Start / End Time: 3:20 PM / 5:00 PM
Room: Bonaparte, Marriott, River Tower Elevators, 4th Floor
Presentation File: No File Uploaded
Fire Island National Seashore is a barrier island that runs parallel to south coast of Long Island. Barrier islands provide important coastal resilience and are landscapes of linked ecosystems. The majority of Fire Island is maintained in a natural state under the management of the National Parks Service. Throughout New England and Long Island there is a recent record of long term salt marsh decline. These losses include creek widening, edge erosion, and interior die-off. This study analyzed salt marsh change with a baseline object-based classification of Worldview 2/3 very high resolution satellite imagery for 2015, aerial imagery, and previous classifications. The aerial imagery were used to delineate non-vegetated panne development from 1994-2015. The non-vegetated pannes accounted for nearly 50% of salt marsh loss from a 1997 classification to the 2015 classification. These lead to the testing of non-vegetated panne development as they related to elevation variables and landscape attributes including distance to water, distance to mosquito ditches, distance to an inlet, distance to a breach caused by hurricane Sandy, and landscape type. The results suggest hydrological factors were the most important indicator of panne expansion. The pannes continued to expand throughout the study period, despite nearly all demonstrating sufficient elevation capital to revegetate. In areas such as Fire Island National Seashore with small tidal ranges, limited sediment budgets, and net vertical accretion being outpaced by regional sea level rise there needs to be continued high resolution remote sensing monitoring to understand salt marsh losses and changes to community composition.