BACTERIAL COMMUNITIES IN A NEWLY REGENERATED MANGROVE FOREST OF SUNGAI HAJI DORANI MANGROVES IN THE WEST COAST OF SELANGOR, MALAYSIA

Abstract

The microbial community is dynamic in a mangrove ecosystem and thus controls various nutrient transformation processes in the ecosystem. In the current efforts to rehabilitate mangroves, this study focused on detecting significant variation within the bacterial community distribution in sediments, at two different depths, of an old regenerated mangrove forest stand of Avicennia marina. The regenerated mangrove forest site was artificially induced by placing wave breakers. Sediment samples were collected at 0–15 cm and 15–30 cm depth and analysed for soil properties. The bacterial community distribution was investigated using high throughput deoxyribonucleic acid (DNA) sequencing of the 16S rRNA gene. Bioinformatics analysis of the DNA sequence data showed that sediments were dominated by Proteobacteria (mostly Gammaproteobacteria and Deltaproteobacteria), followed by Firmicutes (Clostridia), Chloroflexi (Anaerolinae and Dehalococcoidetes), Actinobacteria (Acidimicrobiia, Coriobacteria), Acidobacteria (RB25 and BPC 102), Bacteroidetes (Saprospirae, Flavobacteriia, Bacteriocedes), Gemmatimonadetes and others. However, the intensity of the bacterial groups differed with respect to sampling depths and soil properties. The DNA sequencing revealed the sustenance of observed phylum in the soils of regenerated mangrove forest as compared to old mangrove stand. This highlights the positive effects of rehabilitation using wave breakers leading to microbial colonisation.