The Gastropod Community Of The Lukut Mangroves, Negeri Sembilan
The community structure of the mangrove gastropods along Sungai Lukut, Negeri Sembilan was determined from February to May 2015. The gastropods were sampled from 4 varying mangrove habitats (river mouth, intact riverine, fringing riverine and freshwater riverine). The line transect with quadrat method was employed to sample the gastropods which were handpicked within quadrats (5m x 5m) from the floor, root, stem, branch and where possible leaves. Among the mangrove tree taxa, Sonneratia alba, Avicennia alba, Rhizophora apiculata and Rhizophora mucronata were the most represented. In total 37 gastropod species from 14 families were sampled from the Lukut mangroves. Higher gastropod density was recorded from the river mouth mangroves (6.94 ind/m2) followed by freshwater (2.21 ind/m2), intact (2.15 ind/m2) and fringing mangroves (1.53 ind/m2). Littoraria scabra (3.31ind/m2) and Nerita lineata (1.34ind/m2, 1.15 ind/m2, and 0.66 ind/m2) were the two most abundant gastropod species sampled. The species richness (S), species diversity (H’) and evenness (J’) were calculated for overall and each of area. S, H and J’ for mangrove trees in overall (1.22, 1.88, 0.86), the river mouth (0.59, 0.97, 0.70), fringing (1.16, 1.47, 0.82), intact (0.99, 1.44, 0.80) and freshwater area (1.39, 1.90, 0.86) were recorded with S, H’ and J’ values for gastropods in overall (4.19, 2.17, 0.60), the river mouth (3.80, 1.89, 0.55), fringing (2.39, 1.87, 0.71), intact (2.87, 1.65, 0.55) and freshwater area (2.95, 1.60, 0.53). In conclusion, disturbance tends to amplify the species abundances but may ultimately reduce density and species richness of gastropod taxa.
Keywords— Gastropod Taxa, Density, Diversity, Species Richness, Evenness, Disturbance.