Dynamic of Mangrove Associated Molluscs in Anthropized Areas of the Cameroon Coastline

Abstract

Due to unabated anthropogenic exploitations, mangrove forests globally are constantly under pressure and degradation, which may result in the reduction of ecosystem functioning and biodiversity. Molluscan fauna, which is one of the main macroinvertebrates that play a major ecological role in nutrient dynamics in mangroves, are sensitive to the changes in their habitat. This survey aims to assess the impact of anthropogenic activities on the diversity of molluscs' communities in the mangrove forest. Anthropogenic disturbances within 20 sampling sites were valued at six mangrove stands and patched scoring the degree of influence according to vegetation, structure, waste and trampling. Molluscs were caught by hand and counted within 1 × 1 m 2 plots placed at three points distant of 50 m established using a straight line transect of 100 m. Upon the 20 sites investigated, five were slightly disturbed, eight moderately disturbed and seven sites were highly disturbed. The mean abundance of molluscs decreased from slightly disturbed areas (172.25 ± 73.09 Ind•m −2 ) to highly disturbed areas (100.57 ± 62.84 Ind•m −2 ). Highly disturbed areas have shown lower species richness (R = 1.09 ± 0.15) and diversity (H' = 2.30 ± 0.31). Human activities in the mangrove forest could particularly have effects on the diversity of molluscs, however, feature potential conservation measures have to be in harmony with the needs of the local population.