VARIATION IN COMPOSITION OF ORGANIC MARINE DEPOSITS IN SEDIMENTS AND THEIR INFLUENCE ON THE GROWTH OF <em>RHIZOPHORA</em> SPP. IN TANJUNG PIAI MANGROVE FOREST

Abstract

The mangrove ecosystem is constantly threatened by the accumulation of pollutants along its shoreline. The presence of organic deposits from marine litter is not only a threat to marine ecosystems, but it also harms mangrove stands. This study investigated the chemical properties of the sediment in Tanjung Piai mangrove forest and the their effect on the growth of Rhizophora spp. Samples were collected from four separate locations, namely, T1: site without organic deposits, T2: site with new organic deposits, T3: site with decomposed organic deposits, and T4: site with decomposed organic deposits. After one year, the largest growth increment (19 cm) of Rhizophora spp. was observed at the site with decomposed organic deposits (T4), compared with sites without organic deposits (T1). The highest levels of nitrogen (N), organic carbon (OC) and cation exchange capacity (CEC) were also found at T4. The growth of Rhizophora spp. and the physicochemical parameters have a positive association with the levels of N, OC, CEC and exchangeable magnesium and exchangeable potassium. This study revealed that OC, N, and CEC were released into the sediment at Tanjung Piai mangrove forest when organic deposits decomposed and were physically and chemically degraded.