Diversity of soil fungal communities under natural and managed peat ecosystems in tropical peatland of Sarawak

Abstract

Fungi are primary decomposers in terrestrial ecosystems which involved in degradation of organic matter, particularly in tropical peatland ecosystem that has high content of organic matter accumulation. Fungi in tropical peatland plays important ecological role in regulating ecosystem functions and services. Understanding soil fungal diversity, composition and structure underlying the tropical peatlands are the preliminary steps to predicting the stability of ecosystem functioning under natural and managed peat ecosystems. The aim of this study was to determine soil fungal diversity and communities in tropical peatland of Sarawak under natural (peat swamp forest, PSF and logged-over secondary forest, LOF) and managed (oil palm plantation, OPP) ecosystems. Fungi from peat samples were isolated and identified based on the 18S rDNA region sequencing. Fungal diversity was measured based on Shannon’s diversity index (H’), Simpson’s diversity index (D), species richness (S) and evenness (E). Bray–Curtis dissimilarity was performed to compare fungal communities between study sites. The fungal diversity measurement indicated that LOF had the highest diversity followed by PSF and OPP. In addition to that, the composition of the fungal communities in LOF resembled PSF, compared to OPP. Distinct fungal communities were observed between PSF and OPP due to the dominance of Aspergillus spp. and Trichoderma spp., respectively. In conclusion, LOF is an important ecosystem to retain relatively high fungal diversity. Different fungal communities were observed, which contained ecologically important fungal groups incorporated into the natural and managed peat ecosystems.