Reflection of stable isotopes and selected elements with the inundation gradient at the Matang Mangrove Forest Reserve (MMFR), Malaysia

Multi-elemental and isotopic fingerprints could help to track changes in mangrove forest productivity and development. This study aims to identify elemental concentrations and stable isotope ratios in inter- and intra-mangrove species along the inundation gradient of the Matang mangrove forest. Matured sun leaves of different mangrove species, namely, Avicennia alba, Rhizophora apiculata, Bruguiera parviflora, and Sonneratia ovata, were collected from the Matang Mangrove Forest Reserve (MMFR). After samples preparation, determination of elemental concentrations and stable isotope ratios were carried out using an Atomic Absorption Spectrometer (AAS) and Isotope Ratio Mass Spectrometry (IRMS) respectively. Trace elements (Mn, Fe, Cu, Zn), cations (Na, K, Ca, Mg) and stable isotope (δ13C and δ15N) ratios were found to follow different patterns along the inundation gradient in the leaves of the sampled plant species. Elemental concentrations of Na, K, Fe, Cu, Zn and Mn along with stable istopic ratio differed significantly within similar and different mangrove species. The results of Rhizophora apiculata elemental concentrations and stable isotope ratios can potentially serve as a baseline to further the research in the MMFR compartments.