Abstract
Mangrove wetlands, which total approximately 150,000 km² worldwide, are essential as transition zones between marine and terrestrial ecosystems on tropical and subtropical coastlines around the world. Studies show a sustained loss in mangrove wetlands throughout the world due to anthropogenic causes and demonstrate a considerable vulnerability of these ecosystems to projected climate change, especially sea level rise. This study used satellite imagery to analyzed historical coverage and significance of changes in mangrove communities to the west of Everglades National Park in a 427 km² coastal region in the vicinity of Everglades City and Naples, in southwest Florida using satellite imageries. Six years where reliable imagery were available were investigated: 1973, 1988, 1995, 2002, 2009 and 2015 to produce an empirical analysis of historical wetland coverage evenly distributed over a period of more than 40 years. Over the period of 1973 to 2015 mangrove cover systematically increased in the study area, with, the total increase of mangrove cover between 1973 and 2015 of 1,770 ±2 ha or 10.0% over the 42 year period. Areas of significant change in ecosystem cover were explicitly shown in the north west corner of the study site near Naples Florida. There is a direct correlation between the loss of salt/brackish marshes and the increase in mangroves, with most of this change located proximate to the upstream coastal barrier Tamiami Trail (Rt. 41). Over the period of 1988 to 2015 salt marshes decreased from 2888 ha to 689 ha (76.14%) in our study area. The total area of wetlands, including salt marshes and mangroves, increased by 27 ha or 0.13% over this 27 year period. Recent sea level rise and the landward barrier highway are suggested as the major cause of this modified coastal squeeze on these wetland ecosystems where salt marshes decreased but mangroves increased.
