The Physicochemical Properties of Sediment and Ground Cover for a Secondary Mangrove System in Thailand

Jumprom, N.; Rodcharoen, E., and Wichachucherd, B., 2021. The physicochemical properties of sediment and ground cover for a secondary mangrove system in Thailand. Journal of Coastal Research, 37(4), 784–792. Coconut Creek (Florida), ISSN 0749-0208.Mangrove forests serve various positive aspects for human use and accumulate sediment and filter impurities from the land and sea. In this study, the investigation was performed on the year-round changes in the physicochemical characteristics of sediment and the percentage of cover of the bottom in a secondary mangrove where public-access mangrove areas and the mouth of the Mae Klong River to the sea at Samut Songkhram province, Thailand. Organic carbon (OC), organic matter (OM), bulk density, and grain size were measured in the sediment samples. The percentage of cover and litter dry weight were estimated using 50-cm2 quadrats. Conductivity, total dissolved solids, pH, and salinity were measured from the sediment. Air and water temperatures were recorded. The study site was divided into upper-, middle-, and low-tide levels. The results showed that tidal levels and months had significantly different (p < 0.05) influences on all of the factors examined. The percentage of OC and percentage of OM increased continuously at the upper levels but were low at the middle and lower levels. The bulk density, however, was low in value in the low-tide zone. In addition to the percentage of cover, the percentage of soil and percentage of aerial root were found mostly in the middle to low zones. The percentage of garbage waste and percentage of litter were not different at different levels, and nor was the dry weight, throughout the period of study. The grain size in each month was classified as clay type, pH, conductivity, total dissolved solid, and salinity obtained from sediment varied significantly (p < 0.05) among levels and months. In summary, the upper level is influenced by the terrestrial runoff. Environmental factors such as climate and geography affect the sediment quality at the middle and lower levels.