ISSN: 2578-4994
Authors: Mamert OF*, Ernest K, Alain NP, Arfao TA, Nectaire Lie NT, Simeon T, Emmanuel Cedric MM and Serge Hubert ZT
Whilst several studies have dealt with the effects of domestic, municipal and industrial pollution on river biodiversity in Cameroon, very little data is available on the impact of bridge construction works on this biodiversity. To fill these gaps in our knowledge, we collected macroinvertebrates of two forest streams between January to June 2020, and then compared their biological indices at the crossings of the bridges under construction with the same indices at sampling stations located upstream and downstream of the bridges under construction. Simultaneously, Measurements of the physicochemical variables were done. The results showed that macroinvertebrate communities were negatively affected by the construction of the bridges because the taxonomic richness, abundance, taxonomic richness of Ephemeroptera-Plecoptera-Trichoptera and abundance of Ephemeroptera-Plecoptera-Trichoptera were significantly different between the sites under the bridges and the reference sites upstream of the bridges. Habitat modifications related to activities of bridge construction (excavation of the edges of the watercourse, cleaning of the bed, installation of the footings of the foundations of the bridges, embankment, stabilization of the bed of the watercourse by the blocks of stones), would be the principal erosion predictors of macroinvertebrates biodiversity. However, this work does not lead to significant long-term changes in the physicochemical quality of waters. The significant impacts of bridges construction on macroinvertebrate diversity indicates henceforth the importance of habitat restoration after the completion of construction works.
Keywords: River Biodiversity; Macroinvertebrates; Bridge Construction Works; Habitat Modification
