Sedimentologists have long observed that mangroves have the ability to retain sediment and increase sedimentation rate in comparison to vegetation-free intertidal zones like mudflat and tidal creeks. Recently, in the context of climate change and ocean acidification, mangrove areas have become of interest to researchers as they can act as a sink for carbon/carbonate (blue carbon). However, there are few multidisciplinary studies that directly correlate the quantitative carbonate budget in mangroves to the nature of carbonate sediments, early diagenetic features and microbial erosion. This project aims to fill this gap by investigating both the changes of pore water carbonate chemistry between mangrove and tidal creeks (Red Sea coast; KSA) as well as sedimentological and diagenetic changes in sediments (petrography). The focus will be on both the meter (i.e., forest, marsh, mudflat) and centimeter (i.e., sedimentary structures) scales. For this project, we are looking for a motivated student/recent graduate, with a strong background in carbonate sedimentology, carbonate chemistry, fieldwork (in-situ analysis pH, pore water sampling…), and laboratory work (ICP-MS).