The development and contributions of secondary ecological succession to protecting eroding mangrove dominated muddy coasts: evidence from the vietnamese mekong delta

Abstract

Recent literature reveals that the ecological restoration of eroding mangrove-dominated muddy coasts (MDMCs) requires human intervention. However, there is limited information regarding secondary ecological succession (SES) in abandoned MDMCs. The Vietnamese Mekong Delta (VMD) coast was selected as a case study in this study to address partially the aforementioned questions. This study was undertaken by the use of semi-structured interviews, field observations, regular monitoring, and analysis of Google images. The findings show that SES development has existed in two forms in two contrasting environments, which are small and fully exposed areas with no structural protection. The SES development first commenced with the formation of entrapping microsites, consisting of patches of grass species ( Ischaemum sp. and Ipomoea pes-caprae ), plant species ( Cyperus stoloniferus ), uprooted Casuarina trees, marine debris, and the aerial roots of mangrove species. These microsites subsequently trapped floating mangrove seeds and propagules to promote the growth of Avicennia and Rhizophora trees. Despite their size, extent, and exposure, these SES areas withstood the region’s strong seasonal waves. However, they have been cleared to make way for other coastal protection measures or replaced by costly coastal erosion control measures, as they were considered as wastelands and/or abandoned areas.