Index of environmental pollution and adaptation of Avicennia marina around the ex-bauxite mining area in Bintan Island

Abstract

Bintan Island has high bauxite resource potential. However, its utilization is not balanced with efforts to restore ex-mining land. Physical damage includes erosion and sedimentation of red mud along the coast and the surrounding mangrove forest. This study aims to determine environmental pollution based on the accumulation of lead (Pb) and chromium (Cr) in redmud found in mangrove forests around the bauxite ex-mining area and the adaptation of Avicennia marina to heavy metals. This research was conducted from April to December 2020. Research survey and laboratory analysis using Atomic Absorban Spectrophotometry. The results showed that Pb in the sediments and organs of A. marina was higher than Cr. The results showed that the mangrove forest around the bauxite ex-mining area of Bintan Island was contaminated with low levels of Pb and Cr metals (CF<1, PLI<1) and the environment is lightly polluted (0<Igeo<1). Adaptation of A. marina showed that the metal uptake mechanism was rhizofiltration (BCF<1, TF<1, BCF<TF) and the physical condition was slightly damaged. There was no significant effect between Pb and Cr metals in the sediments and organs of A. marina on the stem diameter and tree height (Sig.> 0.05).