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Publication
Effectiveness of acoustic lures for increasing tropical forest understory bat captures
Aylen, Oliver; Bishop, Philip J.; Rodzay bin Haji Abd Wahab; Grafe, T. Ulmar (John Wiley & Sons Ltd., 2022)

Bats are the most diverse mammalian order second to rodents, with 1400+ species globally. In the tropics, it is possible to find more than 60 bat species at a single site. However, monitoring bats is challenging due to their small size, ability to fly, cryptic nature, and nocturnal activity. Recently, bioacoustic techniques have been incorporated into survey methods, either through passive acoustic monitoring or acoustic bat lures. Lures have been developed on the premise that broadcasting acoustic stimuli increases the number of captures in harp traps or mist nets. However, this is a relatively new, niche method. This study tested the efficacy of two commonly used acoustic bat lure devices, broadcasting two different acoustic stimuli, to increase forest understory bat captures in the tropics. This is the first time an acoustic bat lure has been systematically tested in a tropical rainforest, and the first study to compare two lure devices (Sussex AutoBat and Apodemus BatLure). Using a paired experimental design, two synthesized acoustic stimuli were broadcasted, a feeding call and a social call, to understand the importance of the call type used on capture rates and genus-specific responses. Using an acoustic lure significantly increased capture rates, while the type of device did not impact capture rates. The two acoustic stimuli had an almost even distribution of captures, suggesting that the type of call may be less important than previously thought. Results indicate a possible deterrent effect on Rhinolophous sp., while being particularly effective for attracting bats in the genera Murina and Kerivoula. This study highlights the effectiveness of lures, however, also indicates that lure effects can vary across genera. Therefore, lures may bias survey results by altering the species composition of bats caught. Future research should focus on a single species or genus, using synthesized calls of conspecifics, to fully understand the effect of lures.

Publication
Differential impacts of acacia invasion on nutrient fluxes in two distinct Bornean lowland tropical rain forests
Salwana Md. Jaafar; Faizah Metali; Siti Nisa Syahzanani Nafiah; Nur E’zzati Supri; Nurhazimah Ahmad; Burslem, David F. R. P.; Rahayu Sukmaria Sukri (MDPI, 2022)

Invasive Acacia species can alter nutrient cycling processes in forest ecosystems, particularly affecting total litterfall production and litter decomposition patterns. This study examined the effects of exotic Acacia mangium Willd. on total litterfall production, nutrient concentrations in leaf litterfall fractions, leaf litter decomposition, and nutrient release in lowland heath (HF) and mixed dipterocarp forests (MDF) in Brunei Darussalam, Borneo. Above-ground litterfall traps were installed in HF and MDF with and without invasive Acacia present, representing four habitat types in total, and monthly collections were conducted for 12 months. Litter decomposition bags were deployed to determine the rates of decomposition and nutrient release. Habitats invaded by Acacia exhibited higher total litterfall production, increased leaf litter concentrations of nitrogen, potassium, and calcium, and increased addition of all nutrients measured in litter (nitrogen, phosphorus, potassium, calcium, and magnesium, especially in the Acacia-invaded mixed dipterocarp forest (AMDF) and nitrogen and potassium in Acacia-invaded heath forest (AHF)), reduced nitrogen and potassium use efficiencies in AHF, and reduced stand-level nitrogen and calcium use efficiencies in AMDF. Litter decomposition rates and nutrient release were lower in AMDF than in the three other habitats. The significantly higher total litterfall production coupled with higher nutrient addition in the two Acacia-invaded habitats is expected to progressively increase the abilities of these habitats to produce large quantities of nutrient-rich litter and will likely eventually lead to an enrichment of nutrients in the soil, thus facilitating further invasion by Acacia, particularly in the MDF.

Publication
Contrasting patterns of woody seedlings diversity, abundance and community composition in Bornean heath and peat swamp forests
Nisa S. Nafiah; Rahayu S. Sukri; Muhammad Y.S.M. Ya’akub; Salwana M. Jaafar; Faizah Metali (International Mire Conservation Group and International Peatland Society, 2022)

The diverse lowland forests of Southeast Asia and Borneo are globally recognised biodiversity hotspots containing rare and endangered species and high levels of plant endemism. Heath and peat swamp forests are Bornean lowland forest types with distinctive plant communities that primarily correspond to a soil water gradient from dryland heath to waterlogged peat swamps. Although tree diversity of Bornean heath and peat swamp forests is well described, little is known of their woody seedling communities. This study investigated diversity, abundance and community composition of woody seedlings in mixed peat-swamp (MSF), heath (HF), kerapah (KF) and Shorea albida peat-swamp (SAP) forests in Brunei Darussalam, Northwest Borneo. Within twenty-two 3 × 3 m plots in these forest types, seedlings of 50 ≤ cm height ≤ 100 were censused and taxonomically identified, and measurements of selected environmental and soil properties were obtained. In total, 84 species of woody seedlings from 71 genera were recorded, with Myrtaceae most abundant in MSF, KF and SAP, while Dipterocarpaceae and Sapotaceae were most abundant in HF. Mean seedling abundance and diversity indices did not differ between forest types, but mean species richness was significantly higher in MSF than SAP. Woody seedling community composition differed between forest types and was influenced by soil properties, with MSF seedling communities influenced by total K concentration and soil pH, while SAP was influenced by soil gravimetric water content and total P concentration. These findings highlight the need for increased research on seedling ecology in tropical heath and peat swamp forest formations to further elucidate mechanisms underlying species diversity in these forests, and to guide programmes for their conservation, sustainable management and reforestation.

Publication
An investigation of different types of forest in Brunei Darussalam and their products' uses for community livelihoods
Siti Mariyah Atiqah Binti Haji Duraim; Md. Shafi Noor Islam, Dr. (Universiti Brunei Darussalam, 2024)
Publication
Synthesis and characterization of visible light active BiOCI-based materials for photocatalytic and photoelectrochemical studies
Nurul Asyiqin @ Nabilah Binti Zulkiflee; Mohammad Hilni bin Harun Sani, Dr. (Universiti Brunei Darussalam, 2023)
Publication
An integrated high-resolution mapping shows congruent biodiversity patterns of Fagales and Pinales
Lyu, Lisha; Leugger, Flurin; Hagen, Oskar; Fopp, Fabian; Boschman, Lydian M.; Strijk, Joeri Sergej; Albouy, Camille; Karger, Dirk N.; Brun, Philipp; Wang, Zhiheng; Zimmermann, Niklaus E.; Pellissier, Lo€ıc (Wiley, 2022)

The documentation of biodiversity distribution through species range identification is crucial for macroecology, biogeography, conservation, and restoration. However, for plants, species range maps remain scarce and often inaccurate. We present a novel approach to map species ranges at a global scale, integrating polygon mapping and species distribution modelling (SDM). We develop a polygon mapping algorithm by considering distances and nestedness of occurrences. We further apply an SDM approach considering multiple modelling algorithms, complexity levels, and pseudo-absence selections to map the species at a high spatial resolution and intersect it with the generated polygons. We use this approach to construct range maps for all 1957 species of Fagales and Pinales with data compilated from multiple sources. We construct high-resolution global species richness maps of these important plant clades, and document diversity hotspots for both clades in southern and south-western China, Central America, and Borneo. We validate the approach with two representative genera, Quercus and Pinus, using previously published coarser range maps, and find good agreement. By efficiently producing high-resolution range maps, our mapping approach offers a new tool in the field of macroecology for studying global species distribution patterns and supporting ongoing conservation efforts.