Cypermethrin is a pyrethroid insecticide commonly used to control bagworm infestation in oil palm plantations. It is applied through spraying onto the leaves where the bagworms reside. This article reports the fate of cypermethrin used in a Malaysian oil palm plantation during a typical dry season through the analysis of cypermethrin residue in environmental and palm oil samples collected from a supervised field trial. Residues of cypermethrin were not detected in the soil samples collected at different depths, water samples collected at different points in the experimental plots, and oil samples extracted from fresh fruit bunches (FFB) harvested from each plot for both single and double dosages of treatment throughout the study interval. Analysis of leaf samples, however, revealed that cypermethrin residue was detected for both pesticide treatments up to day 2 after cypermethrin application.

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Understanding the microbial processes that regulate methane emissions in the tropical peatlands can facilitate their future management. However, the microbiota of Malaysian tropical peatlands specifically the methanogens (methane producers) and methanotrophs (methane consumers) remains poorly characterised. This study aimed to determine the key players in methane production and to assess their spatial distribution in different oil palm management zones (i.e., avenue, cover crop, frond pile, and weeded circle) across depths namely 0–15 cm, 15–30 cm, and 30–45 cm in an 11-year-old oil palm plantation that was established on the peatland of Sarawak. Based on high-throughput Illumina sequencing targeting the 16S hypervariable V4–V5 regions of archaeal rRNA amplicon, the diversity indices (Shannon and Simpson) and richness (Chao1 and ACE) were highest in the upper peat layers across management zones, and the microbial diversity and composition are influenced by depths. Taxonomic profiling revealed that the domain Archaea was dominated by Halobacteriota, Thermoproteota, and Thermoplasmatota that increased with depth across management zones. Meanwhile, the order Methanomassiliicoccales was predominant, with Methanomethylophilus sp002495325 as the most abundant species in the upper peat layers in the frond pile zone due to a high decomposition rate of organic matter. The key players of methanogenic archaea belonging to Methanomassiliicoccales, Methanosarcinales, Methanomicrobiales, and Methanobacteriales were detected in oil palm peat soils, providing indirect genetic evidence for the biogeochemical processes associated with methane production in the oil palm plantation. Having established the feasibility of utilising high-throughput sequencing to characterise the archaeome of Malaysian oil palm plantation, future works in correlating the relative abundance of methanogens and methanotrophs with methane production will be instrumental in providing valuable insights for prediction and mitigation of methane emissions in oil palm cultivation on peat.

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.

Sago palm is one of the commodities being cultivated and traded in Malaysia for its high starch content. Sago seedling, or commonly referred to as sucker, is the planting material for sago cultivation. This paper discusses the life cycle assessment approach for the calculation of life cycle inventory for the production of one sago sucker. In this study, the functional unit is defined as one sago sucker. The process starts from the reception of suckers from suppliers, raft preparation, planting sago suckers in rafts, fertilization, and ends with transportation of the suckers to the plantation. Interviews and data verification were done on-site at the Crop Research and Application Unit (CRAUN) Sungai Talau Research Station. LCI data showed that water was the main input for the production of sago sucker, followed by diesel for transportation, pesticides, and fertilisers. The outcome of this study provides a basis or guideline to planters in implementing sago best agricultural practices for the production of sustainable sago.