Abstract

Mangroves are recognized worldwide as one of the most remarkable ecosystems because of their exceptional biological diversity whose origins are terrestrial, marine or intertidal. Mangroves play a role in coastal protection, biodiversity maintenance, flood mitigation, storm protection, pollution control, and coastal erosion reduction. This study was conducted with the aim of determining the impact of anthropogenic activities on the structure of some biological components in the mangroves of the Cameroon Estuary. The work took place at seven sites in the study area, spread across the Littoral and Southwest regions from February to December 2019. Inventories were carried out on all trees of at least 5cm in diameter in plots of 2500m2 (50m x 50m). Species were identified and counted, and parameters such as circumference, height, or distance between two neighboring trees were measured. The results identified 24 species belonging to 12 families. The “Bois des Singes” (1100 individuals/ha) and Tiko (850 individuals/ha) sites showed higher densities, while the Youpwè site showed the lowest density (125 individuals/ha). The diameters varied significantly (K=11.48; p=0.04) between the Bobongo (33.07±23.10cm) and “Bois des Singes” (18.14±7.94cm). Heights also varied significantly (K=12.22; p=0.03) between Tiko (20.28±10.41m) and “Bois des Singes” (11.98±4.59m). Distances between neighboring trees did not vary significantly between the sites (K=9.17; p=0.1). The calculated basal area was higher at Tiko (36.84m2/ha), and lower in “Bois des Singes” (8.87m2/ha). The free and gratis exploitation of the mangrove’s natural resources leads to its degradation. However, the absence of the use of these resources can also become a disadvantage because the progressive dynamics of the mangroves can lead to channel obstruction.

Keywords: Anthropogenic activities; Biodiversity; Cameroon estuary; Mangroves; Vegetation dynamics