Re ECF Project: 2013-27

Project Title: Composition and Genetic Diversity of Microbial Communities in Mai Po Nature Reserve

Applicant: Professor Wong Chong Kim of The Chinese University of Hong Kong

Total Approved Grant: $499,380

Duration: 1/3/2015 to 31/10/2016

Project Status/Remarks: Completed

This project aims to examine the composition and genetic diversity, as well as the spatial and seasonal patterns, of microbial communities in sediments of Mai Po Nature Reserve using ion semiconductor sequencing. The study will provide baseline information for future studies of the microbial ecology of Mai Po. Information on microbial diversity will contribute to future conservation studies and facilitate suitable conservation management of the internationally important Ramsar wetland.

Summary of the Findings/Outcomes:
Mai Po sediments were dominated by the bacterial phyla Bacteroidetes, Chloroflexi and Proteobacteria, the archaeal phyla Crenarchaeota and Euryarchaeota, and the fungal phylum Ascomycota. There were ~6,000 to ~8,000 observed operational taxonomic units (OTUs) of bacteria, ~1,300 to ~2,000 observed archaeal OTUs, and ~300 to ~900 observed fungal OTUs. Bacteria, archaea and fungi showed different degrees of spatial and seasonal variations. Composition and diversity of bacteria showed significant seasonal differences in both mudflat and mangrove samples, and spatial difference between mudflat and mangrove samples in the dry season. Composition of fungi differed significantly between seasons in both mudflat and mangrove samples. Fungal diversity differed spatially between mudflat and mangrove samples during the dry season. There were no obvious spatial and seasonal variations in archaeal composition and diversity. Temperature, total carbon, archaea diversity, and fungal richness were major factors driving the bacterial community structure. For archaea, major drivers included fungal richness and bacterial diversity, whereas temperature, bacterial richness and archaeal diversity were major drivers of the fungal community.