Physicochemical properties and bacterial diversity of pristine and stressed Malaysian mangrove ecosystems

Recent microbiome research highlights the complexity and specialisation of microbial communities living in mangrove ecosystems. Distinct prokaryotic community structures reflect the unique environmental conditions and ecological processes in these habitats, emphasising their key roles in biogeochemical transformation and nutrient cycling. Here we highlight the changes in bacterial diversity and community structures in sediments from two contrasting Malaysian mangrove ecosystems, Tanjung Piai mangroves as a degraded pollution-affected site and Matang Mangrove Forest as a pristine well-preserved site, using 16S rRNA gene amplicon sequencing approach. Higher organic carbon and organic matter contents in Matang, in contrast to the higher available phosphorus content in Tanjung Piai sediment, clearly showed differences in the bacterial diversity of both sites. We also observed higher species richness and community diversity in Tanjung Piai, suggesting a more heterogeneous bacterial population potentially influenced by external nutrient inputs and other confounding factors due to anthropogenic activities. Collectively, the findings suggested a possible relationship between specific anthropogenic activity-related variables in mangrove sediment and individual bacterial taxa. Thus, understanding the complex interactions of soil sediment microbiome within the habitat could facilitate the assessment of impact from stress factors and identify mangrove ecosystems needing rehabilitation, as part of the mangrove conservation strategies.