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ABSTRACT The Buffalo Reef deposit is a developed gold mine located in the northern part of Pahang State, within the Central Belt of Peninsular Malaysia. The gold deposit is hosted by the Permo‐Triassic Gua Musang Formation, which consists of shale, carbonaceous shale, mudstone, siltstone, volcanic rocks and low‐grade metamorphic rocks. Gold ore at Buffalo Reef is found in quartz veins and alteration selvages, which fill ductile‐brittle structures along N–S and NE–SW striking faults and shear zones. The sulphide minerals associated with gold ore include pyrite, arsenopyrite, stibnite and minor amounts of galena. Geochemical studies of gold grains reveal that the gold is alloyed with less than 10 wt% Ag and contains no other minor elements, with fineness of gold grains ranging from 882 to 990. Sulphur isotope analysis of sulphide minerals extracted from auriferous veins shows a narrow range of δ34S values from −2.40‰ to +2.70‰ (n = 29). The δ34S composition close to zero relative to VCDT for all sulphide minerals indicate that these minerals are isotopically uniform and derived from a single source. The overlapping sulphur isotope data between the sulphide minerals from the Buffalo Reef and those from other gold deposits in the Central Belt suggest that the sulphur in the ore‐forming fluids responsible for the auriferous quartz veins at Buffalo Reef is likely related to devolatilisation from metamorphic fluids at depth in an orogenic system. However, the substantial contribution of magmatic fluid cannot be ruled out due to the narrow range of sulphur isotopic compositions around zero per mil. The results of this study indicate that gold mineralisation in the study area and in other gold deposits along the Bentong‐Raub Suture Zone in the Central Belt is of the orogenic type. [ABSTRACT FROM AUTHOR]

Integration of land and marine vertical datums is an important aspect of geospatial reference systems. Therefore, this study has been conducted to identify an optimum approach to integrate the marine and land vertical datums. Two hybrid geoid models have been developed and fitted to the the land levelling datum at benchmark and to the tide gauge-benchmark station (TGBM). The differences between the two hybrid geoid models were computed to establish a vertical datum transformation model (VDT). Among the 305 GNSS-levelling points, 295 have been used in the hybridization process and 10 have been used for validation. Based on the comparison, the geoidal differences at the 10 points range from −7.2 to 7.0 cm while the mean and RMSE of differences are 1.3 cm and ± 4 cm, respectively. The second hybrid geoid, which was fitted to local MSL, was developed by directly adding to the offset between the gravimetric geoid and local MSL at nine TGBM stations. The result indicates that the offset derived at Tanjung Gelang is the optimum one with an RMSE of ± 0.045 m. The VDT model developed shows a transformation accuracy of approximately ± 4 cm. [ABSTRACT FROM AUTHOR]

Aujeszky’s disease (AD) is a common disease that has spread worldwide. Various porcine viral diseases exist in Malaysia, where AD is the most common viral endemic disease in the country. The serological status of AD in Peninsular Malaysia was reported prior to 2018, but information after that date is very limited. Hence, our study investigated AD’s serological status in Peninsular Malaysia pig farms based on commercial samples submitted to the Faculty of Veterinary Medicine, Universiti Putra Malaysia, between 2019 and 2021. In this study, 2,780 serum samples were taken from 61 farms, and an enzymelinked immunosorbent assay (ELISA) test was performed using the IDEXX Pseudorabies Virus gpl Antibody Test Kit for AD serology diagnosis. The results showed that the overall seropositive rate of Aujeszky disease virus (ADV) was 1.51% (42/2,780), which dropped from 2.62% (23/879) in 2019 to 0.53% (5/937) in 2020 and 1.45% (14/964) in 2021. In addition, 18.03% (11/61) of the 61 farms that submitted samples were infected with AD. The results indicate that AD still exists in Peninsular Malaysia, and some farms are at risk from the disease. Further analysis suggested that the quarterly seroprevalence of ADV may also be related to region. This study provides serological data on AD in Peninsular Malaysia, which helps to understand the prevalence and serological status of the disease. [ABSTRACT FROM AUTHOR]

Mass oyster mortality occurred at an oyster farm in the Setiu Lagoon on the east coast of Peninsular Malaysia in December 2023. According to interviews with aquaculture farmers, heavy rains that occurred from 20 November to early December caused flooding in the surrounding area, leaving it exposed to low-salinity water for a long period. Mass mortality occurred at oyster farms in early December, with farmers estimating that the dead oysters had a shell length of 1–5 cm and mortality rate of over 90%, and that approximately 50,000 oysters had died. An analysis of meteorological data indicated that a monthly rainfall value of more than 1200 mm/month, which is more than double the normal amount, was observed in November in the same region. During the same period, the seawater temperature in the South China Sea was 1°C higher than normal, and the northeast monsoon caused winds from the northeast to transport moist air to the eastern coast of Peninsular Malaysia, causing heavy rain. Currently, only one waterway, approximately 200 m wide, connects the lagoon to the sea. Until approximately 2012, two waterways were connected to the sea. We concluded that by increasing the number of channels to two, the decrease in salinity in the lagoon during the rainy season could be reduced by enhancing phytoplankton occurrence.

Phytoremediation technology utilises the ability of plants to remove metal toxicity in the soil. Bamboo is one of the fast-growing woody plants that may potentially facilitate the immediate removal of toxic metals from the soil. This study was conducted to identify the potential of Dendrocalamus asper in phytofiltering metal elements from the mining sites such as the Chini watershed in Pahang. Dendrocalamus asper was grown in a greenhouse with several applications of bamboo biochar (BB) and EDTA in addition to the efficiency test in reducing soil contaminants for 100 days. The present study found Dendrocalamus asper with the addition of BB+EDTA had reduced 37.44% Fe, 43.72% As, 79.27% Pb, 22.67% Cd, and 48.60% Al concentration in the soil. The same treatment also showed a higher plant accumulation of metal concentrations Pb (31-fold) followed by Al (1.3-fold), Cr (1.3-fold), As (1.05-fold), Fe (82%) and Cd (81%) compared to the control. Growing bamboo with the combination of BB+EDTA was found to be useful for Pb phytoextraction and suitable as a phytostabiliser for Al, Fe, As, Cr and Cd. The understanding in the potential of Dendrocalamus asper in reducing soil contaminants may benefit stakeholders in managing and r estoring contaminated sites in the fut ure. [ABSTRACT FROM AUTHOR]

The most sought-after timber bamboo species in Peninsular Malaysia, Gigantochloa scortechinii (Buluh semantan, GS), is directly harvested from forests due to a lack of large-scale plantations. GS was confused with its hybrid species (×Gigantocalamus malpenensis, GM), resulted from natural hybridisation with another wild common species, Dendrocalamus pendulus (Buluh akar, DP). This study assessed the similarity and distinctiveness of chemical constituents in DP, GM and GS. On the basis of hybrid intermediacy, we assumed that a chemical property is likely to be heritable if its level in GM is intermediate between those of DP and GS. Culms of all species were collected from the logged-over forests in Perak. Culm dimensions, density and moisture were measured for each species. Based on the Technical Association of the Pulp and Paper Industry (TAPPI) standards of testing methods, the contents of cellulose, hemicellulose, lignin, ash and solvent extractives were analysed for 18 samples (six for each species) using ANOVA and Tukey's test. DP culms are the longest and they have significantly longer (p < 0.05) internodes, smaller diameter and thinner walls than those of GM and GS. GS has a relatively high cellulose content (58.38 ± 1.19%, crystallinity index = 78.30%). Cellulose, hemicellulose and lignin were significantly (p < 0.05) different between DP and GS by 6.31%, 5.70% and 6.27%, respectively. Whereas, those of GM were intermediate, implying that they are heritable characteristics. Lignocellulose contents are rather consistent within each of these species, that is low relative standard deviation (RSD), while ash content and solvent extractives exhibit higher intraspecies variation, possibly attributed to stronger environmental influences than genetics. Based on its chemical properties, we suggested that prospective biomaterials for biofuels, chemicals, pulps and fabrics can be der ived from GS. [ABSTRACT FROM AUTHOR]

This study was conducted at the Tranum Forest Reserve, Raub, Pahang to determine the community structure, species diversity and biomass of trees in the area. Four study plots, each measuring 25 m x 20 m, were established at the study site, which covered a total area of 0.2 ha. All trees with diameter at breast height (DBH) of 5 cm and above were measured and recorded. A total of 175 trees was enumerated in the study plots, comprising 106 species and 79 genera from 40 families. The largest family was Lauraceae, represented by 11 species from six genera, followed by Myrtaceae with eight species from one genus. Tree species diversity of the study area was high, as reflected by a Shannon Diversity Index (H') value of 4.49 (Hmax = 4.66). Margalef Richness Index (R') and Shannon Evenness Index (E) showed values of 20.33 and 0.84, respectively. The most important family, based on the highest Family Important Value Index (FIVi), was Dipterocarpaceae, with a value 17.31%. Shorea platyclados was the most important species with Important Value Index (IVi) of 17.04%. The tree density of the study area was 875 indidivuals per hectare (ind/ha), with Lauraceae being the densest family at 85 ind/ha. Vitex gamosepala was the densest species at 40 ind/ha. The total basal area of trees was 66.23 m²/ha, with Dipterocarpaceae showed the highest basal area of 31.69 m²/ha and Shorea platyclados had the highest basal area of 31.69 m²/ha at species level. The total biomass of trees was estimated at 1,307.56 t/ha, of which the above ground biomass and the below ground biomass were 1,091.33 t/ha and 216.23 t/ha, respectively. Dipterocarpaceae contributed the highest biomass with an estimate of 743.83 t/ha and Shorea platyclados showed the highest biomass at species level with 743.83 t/ha. [ABSTRACT FROM AUTHOR]

This article presents a reflective microcosm to faithfully echo the intricate history of Chinese immigration in Peninsular Malaysia, focusing on two migration waves that occurred during the Malacca Sultanate and colonial eras. It meticulously examines the underlying causes, defining the characteristics, patterns and quantities of each immigration wave by drawing upon historical documents, tombstone inscriptions and demographic data. In a significant departure from conventional wisdom, this study challenges the prevailing notion that Chinese immigrants were overwhelmingly male, shedding light on the fact that the initial wave featured a higher proportion of females. Moreover, the analysis illuminates the intricate interplay between local colonial policies and the external factors emanating from China, demonstrating their profound influence on migration patterns and quantities. The present quantitative study offers fresh insights into the multifaceted experiences of Chinese immigrants in Peninsular Malaysia. It underscores the key findings while bringing attention to the associated complexities and nuances. [ABSTRACT FROM AUTHOR]

Neotropical cichlid possesses territorial aggression which explains their success as alien species that pose threats to local fauna. The feeding ecology of Midas cichlid, Amphilophus citrinellus species outside its native range had never been fully understood. We aim to determine the stomach content, length-weight relationship and condition factor of this non-native species in one of the agroecosystems in Malaysia. The fish was collected using a cast net, and the guts were dissected. The stomach content (n = 35) revealed Midas cichlids feed on a wide array of preys including fish, amphibian and gastropod. The b-value is 2.60 (negative allometric growth) and the relative condition factor, Kn is 1.04. This result represents an initial study on the feeding aspect of this cichlid. Subsequent and continued researches are needed to evaluate the feeding behaviour and prey preferences of this species in its introduced range. [ABSTRACT FROM AUTHOR]

Rising temperatures due to global warming necessitate immediate evaluation of heatwave patterns in Peninsular Malaysia (PM). For this purpose, this study utilized a locally developed heatwave index and a gridded daily maximum temperature (Tmax) dataset from ERA5 (1950–2022). During validation, the ERA5 dataset accurately represented the spatial pattern of Level 1 heatwaves, showing widespread occurrence. Historically, Level 1 heatwaves prevailed at 63.0%, followed by Level 2 at 27.7%, concentrated in northwestern states and the enclave between the Tahan and Titiwangsa mountain ranges. During very strong El Niño events in 1982/83, 1997/98, and 2015/16, Level 2 heatwave distributions were 10.4%, 26.8%, and 15.0%, respectively. For future projection, the model ensemble was created by selecting top-performing Global Climate Models (GCMs) using Kling-Gupta efficiency (KGE), ranked re-aggregation with compromise programming index (CPI), and GCM subset selection via Fisher-Jenks. The linear scaling bias-corrected GCMs (BC-GCMs), NorESM2-LM, ACCESS-CM2, MPI-ESM1-2-LR, ACCESS-ESM1-5, and FGOALS-g3, were found to exhibit better performance, and then ensemble. March to May show the highest increase in all scenarios, ranging from 3.3 °C to 4.4 °C for Level 1 heatwaves and 4.1 °C to 10.7 °C for Level 2 heatwaves. In the near future, SSP5-8.5 projects up to a 40.5% spatial increase for Level 1 heatwaves and a 2.3% increase for Level 2 heatwaves, affecting 97.1% and 57.2% of the area, respectively. In the far future, under SSP2-4.5 and SSP5-8.5, Tmax is projected to rise rapidly (1.5–4.5 °C) in the northern, western, and central regions, with increasing population exposure anticipated in the northern and western regions. [ABSTRACT FROM AUTHOR]

The Spine Bahaba (Bahaba polykladiskos), locally known as 'Gelama Tirusan,' is a member of the Sciaenidae fish family that is distributed across Southeast Asia, reaching as far as North Australia. This species is renowned for its swim bladder, which produces a distinctive loud sound. Despite its distribution in Southeast Asia, no previous studies have reported the presence of the Spine Bahaba in Peninsular Malaysia. This research aims to document the first-ever record of B. polykladiskos in Muar River, Johor, and provide ethnoichthyological insights regarding this species. The ethnoichthyological data were collected using a convenience snowball sampling technique, involving the collection of information from communities residing in the Muar area. In total, 47 respondents participated in the study. The results indicate that a majority of the respondents were familiar with (98%) and had encountered (94%) B. polykladiskos in both the Muar River and the local fish market. The study also documented the demand and trade associated with B. polykladiskos in Muar, with recorded prices ranging from RM 20 to RM 11,500 per fish. Furthermore, this research provides an introductory description of the uses and perceived benefits of B. polykladiskos in traditional medicine, particularly in relation to sexual prowess among male respondents. The study successfully establishes a baseline information for B. polykladiskos in Peninsular Malaysia using an ethnoichthyological approach, thus extending the known geographical distribution of this distinctive species. [ABSTRACT FROM AUTHOR]

Rumen flukes cause heavy economic losses in the ruminant industry worldwide, especially in tropical and subtropical countries. This study estimated the prevalence of rumen flukes in buffaloes, identified the species diversity, and determined risk factors associated with rumen fluke prevalence in Perak, Peninsular Malaysia. A cross-sectional study was conducted, and 321 faecal samples were collected from six buffalo farms. A structured questionnaire was developed, and farmers were interviewed to obtain information regarding risk factors associated with rumen fluke infection. The faecal samples were examined using sedimentation and Flukefinder® techniques. Genomic DNA was extracted from the fluke eggs recovered using the Flukefinder® method, and the internal transcribed spacer 2 (ITS2) fragment was amplified and sequenced to facilitate species identification. The results showed that the overall prevalence of rumen fluke across the sampled farms was 40.2% (129/321). Three rumen fluke species were identified, namely, Fischoederius elongatus, F. cobboldi, and Orthocoelium streptocoelium. Several management factors had a significant association (P < 0.05) with rumen fluke prevalence, including production type, cleaning of the stable, drinking water system, flooding around the farm, grazing system, pasture sharing with other livestock, and deworming program. This work constitutes the first attempt to understand the epidemiology of rumen fluke infection in the region and suggests that good farm management, pasture management, choosing appropriate drugs, and proper husbandry practices may improve buffalo health and production in areas where rumen flukes are prevalent. [ABSTRACT FROM AUTHOR]

Abstract One of the direct and unavoidable consequences of global warming-induced rising temperatures is the more recurrent and severe heatwaves. In recent years, even countries like Malaysia seldom had some mild to severe heatwaves. As the Earth's average temperature continues to rise, heatwaves in Malaysia will undoubtedly worsen in the future. It is crucial to characterize and monitor heat events across time to effectively prepare for and implement preventative actions to lessen heatwave's social and economic effects. This study proposes heatwave-related indices that take into account both daily maximum (Tmax) and daily lowest (Tmin) temperatures to evaluate shifts in heatwave features in Peninsular Malaysia (PM). Daily ERA5 temperature dataset with a geographical resolution of 0.25° for the period 1950–2022 was used to analyze the changes in the frequency and severity of heat waves across PM, while the LandScan gridded population data from 2000 to 2020 was used to calculate the affected population to the heatwaves. This study also utilized Sen's slope for trend analysis of heatwave characteristics, which separates multi-decadal oscillatory fluctuations from secular trends. The findings demonstrated that the geographical pattern of heatwaves in PM could be reconstructed if daily Tmax is more than the 95th percentile for 3 or more days. The data indicated that the southwest was more prone to severe heatwaves. The PM experienced more heatwaves after 2000 than before. Overall, the heatwave-affected area in PM has increased by 8.98 km2/decade and its duration by 1.54 days/decade. The highest population affected was located in the central south region of PM. These findings provide valuable insights into the heatwaves pattern and impact.

The fern species richness assessment was done along environmental gradients in Ayer Hitam forest reserve, Johor, Peninsular Malaysia. This was done to ascertain the distributional pattern of the ferns as influenced by the environmental gradients in this forest. The collection of the fern species was done using a preferential non-random sampling technique. Temperature, humidity, light intensity, and elevation data were obtained at each point of collection of the ferns. The influence of these environmental gradients on the distribution of the species was determined using detrended correspondence analysis (DCA) and general linear model (GLM). A total of 67 ferns were identified at all the study sites. Two ferns namely Asplenium antiquum and Pteris longipinnula were first recorded in this study. In all the sites, light intensity ranges from 337.9 - 8098 lux, temperature ranges from 28.5 - 33°C, humidity ranges from 66.24 - 88.80%, and elevation ranges from 14-33m. Tectaria singaporeana and Nephrolepis biserrata are the only species that are widely distributed across all the study sites. The DCA revealed that the light intensity influences the distribution of the fern species in this forest. However, the GLM showed that temperature had a positive influence on the distribution of the ferns while light intensity had a negative influence on them. [ABSTRACT FROM AUTHOR]

The gut microbiome refers to the microorganism community living within the digestive tract. The environment plays a crucial role in shaping the gut microbiome composition of animals. The gut microbiome influences the health and behavior of animals, including the critically endangered Malayan tiger (Panthera tigris jacksoni). However, the gut microbiome composition of Malayan tigers, especially those living in their natural habitats, remains poorly understood. To address this knowledge gap, we used next-generation sequencing DNA metabarcoding techniques to analyze the gut microbiome of wild Malayan tigers using fecal samples collected from their natural habitats and in captivity. Our aim was to determine the gut microbiota composition of the Malayan tiger, considering the different types of habitat environments. The results revealed a diverse microbial community within the gut microbiome of Malayan tigers. The prominent phyla that were observed included Firmicutes, Proteobacteria, Actinobacteriota, Fusobacteriota and Bacteroidota. Beta diversity analysis revealed significant differences in gut microbiome composition of Malayan tigers that inhabited oil palm plantations, in villages and protected areas. Diversity analysis also revealed significant difference in the gut microbiome between wild and captive Malayan tigers. However, the distinctions of gut microbiome between wild and captive alpha diversity did not yield significant differences. The differences in microbiome diversity resulted from the interplay of dietary intake and environmental factors. This information will facilitate the establishment of focused conservation approaches and enhance our understanding of the effect of microbiome composition on Malayan tiger health. [ABSTRACT FROM AUTHOR]

An episode of extreme monsoonal flood event has severely affected the East and West coast of Peninsular Malaysia from 16th to 18th December 2021. The extreme rainfall was documented to be associated to Tropical Depression 29 and Typhoon Rai. In addition, biomass burning aerosols were suspected to be capable of intensifying the precipitation. Thus, the main causes of this extreme event are studied with model evaluation being carried out with biomass burning as one of the possible reasons and variables. From the sensitivity analysis on the PBL scheme for the model physics, QNSE scheme is tested to be the best scheme to simulate the episode compared with MYJ and ACM2 and used in the model assessment. The performances of ARW (WRF-ARW), BB (WRF-Chem with biomass burning), and NOBB (WRF-Chem without biomass burning) have been assessed in the reproduction of the precipitation pattern and tropical depression. Simulation results indicate that ARW shows an overall better performance for most meteorological variables with better performance in reproducing the surface-level pressure and wind speed. Model scenarios of ARW and BB produced similar tropical depression spatial distributions but differ in magnitude, where the tropical depression in ARW is stronger during the study period over East coastline. All models overestimate the precipitation intensity, but ARW is much better correlated with observation data followed by NOBB and BB. The findings show that biomass burning aerosols have only a minor impact on intensifying or delaying the rainfall event. Therefore, tropical depression over Peninsular Malaysia is shown to be the main causation to this extreme event in 2021. The model could be applied for the future flood risk management in Malaysia to provide information on decision making. [ABSTRACT FROM AUTHOR]

The accurate prediction of the onset and withdrawal of the southwest monsoon (SWM) is crucial to the economic and social well-being of the local community whose livelihoods depend strongly on monsoon rains. To date however, there has been a paucity of research into the prediction of SWM timing in east coast Peninsular Malaysia (ECPM) as compared to other monsoon regions. Thus, this study attempts to identify the variability of SWM dates in ECPM and analyze the influence of ENSO on the timing of SWM. Composites of daily 850 hPa zonal winds and outgoing long-wave radiation (OLR) during 2000-2020 were analyzed. The SWM onset is identified by the sudden acceleration of southerly winds in mid-May, while the retreating SWM wind is recognized by the steady decrease of westerly winds through September until October. The average date of SWM onset and withdrawal over ECPM was found to be May 23rd and September 27th, respectively. ENSO has a greater influence on the SWM onset than the SWM withdrawal. The study adds to our understanding of the inter-annual variability of SWM start and retreat dates, laying the groundwork for future research into the impact of climate change on the monsoon timing variability in the study area.

To understand the habitat status of Pholas orientalis offshore of Selangor, which is an important fishing ground in Malaysia, P. orientalis was obtained from the region in August and November 2014. The shell sizes and weights of the specimens were measured, and tissue sections of various organs were prepared, stained with hematoxylin and eosin solution, and observed under a light microscope. The results obtained for the gonads, digestive tube, and midgut gland were summarised, and the results showed that many individuals of both sexes had already reached the mature stage in August, and the maturation was almost synchronised in both sexes. In November, more than 40% of both sexes entered the spawning stage, suggesting that the spawning peak in the region occurred during the rainy season. From observations of the presence or absence of food in the digestive tube and epithelium condition estimation of the midgut gland, food presence in the clams was confirmed in more than 80% of individuals in both months, and the epithelium condition was also good. In addition, from the Global Eutrophication Watch internet homepage, chlorophyll-a concentration data on the fishing ground area were shown as the stable phytoplankton occurrence area. Therefore, these data suggest that suitable food availability is an important factor for the habitation of this species.

La loche aux yeux de feu Barbucca diabolica, rencontrée dans les eaux douces d’Asie du Sud-Est, est actuellement connue en Thaïlande, en Malaisie occidentale, à Sumatra et à Bornéo. Malgré cette large distribution, il n’y a pas de signalement publié sur cette espèce pour l’île de Belitung (Indonésie). Nous rapportons ici une première occurrence de B. diabolica pour cette île, sur la base de deux spécimens collectés dans la province orientale de Belitung. Ce nouvel enregistrement étend la distribution de l’espèce d’environ 600 km au sud-est de Johor (péninsule malaise, Malaisie), d’environ 400 km à l’est de la rivière Musi (Sumatra, Indonésie) et d’environ 500 km au sud-ouest de la rivière Kapuas (Bornéo, Indonésie). Il s’agit aussi de l’enregistrement de l’espèce sur une île supplémentaire dans la Région du Sundaland. [ABSTRACT FROM AUTHOR]

Plasmodium cynomolgi is a simian malaria parasite that has been increasingly infecting humans. It is naturally present in the long-tailed and pig-tailed macaques in Southeast Asia. The P. cynomolgi Duffy binding protein 1 region II [PcDBP1(II)] plays an essential role in the invasion of the parasite into host erythrocytes. This study investigated the genetic polymorphism, natural selection and haplotype clustering of PcDBP1(II) from wild macaque isolates in Peninsular Malaysia. The genomic DNA of 50 P. cynomolgi isolates was extracted from the macaque blood samples. Their PcDBP1(II) gene was amplified using a semi-nested PCR, cloned into a plasmid vector and subsequently sequenced. The polymorphism, natural selection and haplotypes of PcDBP1(II) were analysed using MEGA X and DnaSP ver.6.12.03 programmes. The analyses revealed high genetic polymorphism of PcDBP1(II) (π = 0.026 ± 0.004; Hd = 0.996 ± 0.001), and it was under purifying (negative) selection. A total of 106 haplotypes of PcDBP1(II) were identified. Phylogenetic and haplotype analyses revealed two groups of PcDBP1(II). Amino acid length polymorphism was observed between the groups, which may lead to possible phenotypic difference between them. [ABSTRACT FROM AUTHOR]

Tea (Camelia sinensis) is one of the most consumed beverages in the world. Research on the nutritional characteristics of tea, particularly lowland tea plantations, is limited in Malaysia. Thus, we aimed to investigate the nutritional characteristics (N, P, K, Ca, Mg, Al, Fe) and antioxidant activity of seven clonal teas (663, 2026, 2024, AT53, TV9, 1294, and 1428) planted at a tropical lowland tea plantation, Bukit Cheeding, Selangor, and their association with the soil edaphic factor. All foliar nutrient concentrations except for Ca and antioxidant activities varied significantly (p<0.05) among tea clones. Clone AT53 had the highest foliar K (1.84 ± 0.7 mg g-1 ), Mg (0.80 ± 0.3 mg g-1 ), Fe (12.97 ± 1.4 mg g-1 ), and Al (16.61± 1.4 mg g-1 ). Clone 663 had the highest P (13.76 ± 1.06 mg g-1 ), and clone 2026 had the highest N (4.39 ± 0.2%). Clone 1248 had the highest antioxidant activity at 50.66 ± 3.2 µg mL-1. Tea foliar N and P concentrations were significantly associated with the N and P of the soil. Besides, several soil nutrients were significantly intercorrelated with foliar nutrient concentrations. Results from this study may benefit growers in selecting better quality clones and managing lowland tea plantation at Bukit Cheeding, Selangor, Malaysia. Good farm management may improve the productivity and sustainability of tea plantations. [ABSTRACT FROM AUTHOR]

Missing values in rainfall records might result in erroneous predictions and inefficient management practices with significant economic, environmental, and social consequences. This is particularly important for rainfall datasets in Peninsular Malaysia (PM) due to the high level of missingness that can affect the inherent pattern in the highly variable time series. In this work, 21 target rainfall stations in the Johor River Basin (JRB) with daily data between 1970 and 2015 were used to examine 19 different multiple imputation methods that were carried out using the Multivariate Imputation by Chained Equations (MICE) package in R. For each station, artificial missing data were added at rates of up to 5%, 10%, 20%, and 30% for different types of missingness, namely, Missing Completely At Random (MCAR), Missing At Random (MAR), and Missing Not At Random (MNAR), leaving the original missing data intact. The imputation quality was evaluated based on several statistical performance metrics, namely mean absolute error (MAE), root mean square error (RMSE), normalized root mean square error (NRMSE), Nash-Sutcliffe efficiency (NSE), modified degree of agreement (MD), coefficient of determination (R2), Kling-Gupta efficiency (KGE), and volumetric efficiency (VE), which were later ranked and aggregated by using the compromise programming index (CPI) to select the best method. The results showed that linear regression predicted values (norm.predict) consistently ranked the highest under all types and levels of missingness. For example, under MAR, MNAR, and MCAR, this method showed the lowest MAE values, ranging between 0.78 and 2.25, 0.93–2.57, and 0.87–2.43, respectively. It also consistently shows higher NSE and R2 values of 0.71–0.92, 0.6–0.92, and 0.66–0.91, and 0.77–0.92, 0.71–0.93, and 0.75–0.92 under MAR, MCAR, and MNAR, respectively. The methods of mean, rf, and cart also appear to be efficient. The incorporation of the compromise programming index (CPI) as a decision-support tool has enabled an objective assessment of the output from the multiple performance metrics for the ranking and selection of the top-performing method. During validation, the Probability Density Function (PDF) demonstrated that even with up to 30% missingness, the shape of the distribution was retained after imputation compared to the actual data. The methodology proposed in this study can help in choosing suitable imputation methods for other tropical rainfall datasets, leading to improved accuracy in rainfall estimation and prediction.

Seaports enable national and international trade in nearly every country around the globe. The new digital world has led most seaport sectors to fully embrace new technologies and tools to better compete with other seaports. Moreover, such maritime activities have potentially significant effects on regional development. The east coast region in Peninsular Malaysia is less developed than the west coast region. It has caused a significant regional development gap, particularly in infrastructure quality, community services, production volume diversification, job opportunities and rising average wealth. Firstly, this study assesses how economic activities affect regional development in Peninsular Malaysia. Secondly, this study aims to identify the challenges and strategies for resolving the regional development imbalance in Peninsular Malaysia. A semi-structured face-to-face interview with fifteen maritime experts was adopted to achieve the proposed objectives. Interview outcomes helped identify and resolve significant problems and create strategies to facilitate the regional development of Malaysian seaports. IR 4.0: These novel strategies may lead to digitalisation in decision-making methods concerning regional development in the Malaysian seaport sector. Integrating four approaches could increase the regional development progress and facilitate continuous growth for the Malaysian seaport industry. The new findings recommend Malaysian seaport digitalisation through progressive regional development. [ABSTRACT FROM AUTHOR]

Growing oil palm among the indigenous peoples in Peninsular Malaysia is not uncommon. While individuals' success either economically or academically are lauded and ought to be nurtured and supported, previous study by Wirth believes that collective success is the key not only in elevating the socioeconomic status but also serves as a mean to retain them as a cohesive unit culturally and socially. This study aims in promoting a model for collective development in the form of cooperative in oil palm cultivation of the indigenous peoples. Through simple random sampling and snowball techniques, a total of fifteen small-scale oil palm farmers from an indigenous village in the state of Pahang were interviewed periodically during the months of June till September, 2020. The results of the study found that these indigenous oil palm farmers faced both social and economic issues between the household members as well as within the indigenous community arising from inequalities of income level. At the macro level, a competent cooperative will attain far greater achievements and more beneficial to the indigenous community than a few successful farmers due to the concept of inclusiveness and sustainability. It is hope that the cooperative model can be replicated in other indigenous communities and effectively raise the overall living standard of the indigenous community in Peninsular Malaysia. [ABSTRACT FROM AUTHOR]

The petiole anatomy of 26 species of Madhuca from Peninsular Malaysia was studied. Methods used in this study were petiole sectioning using a sliding microtome, staining, mounting and observation under light microscope. This is the first report on a comprehensive petiole anatomy of selected Madhuca species from Peninsular Malaysia. The results had shown that there were five types of petiole outlines, and ten types of vascular bundles on the petiole of species studied. All species have sclerenchyma cells in the abaxial side except in M. motleyana, which has clusters of sclerenchyma cells scattered throughout the cortex. The findings showed that two types of crystals and latex canal were shared in all species studied. Only five species out of 26 have trichomes on their petiole. The evaluated petiole anatomical characteristic features proved to be a useful tool for the taxonomic discrimination of the 26 studied species. [ABSTRACT FROM AUTHOR]

Drought assessment has attracted attention in the research community, especially regarding the accuracy of drought indices due to input data uncertainty. This study addressed the impacts of input data uncertainty on the estimation of the Standardized Precipitation Index (SPI) and Standardized Precipitation Evapotranspiration Index (SPEI) for drought assessment in Peninsular Malaysia. The Kolmogorov-Smirnov test recommended the gamma distribution function for the SPI and the log-logistic distribution function for the SPEI. The bootstrap method was used to estimate SPIU and SPEIU, which account for input data uncertainty, and provided estimates for SPI and SPEI values. However, the standard deviation indicated significant input data uncertainty, with values ranging from 0.1038 to 0.1378. The two drought indices exhibited similar classifications of drought categories, but SPIU showed greater uncertainty for very dry and extremely dry events. The findings emphasize the importance of input data uncertainty, especially when dealing with extreme drought events. [ABSTRACT FROM AUTHOR]

Waterbird populations are rapidly declining worldwide, including in many countries in Southeast Asia. Massive land use changes in Peninsular Malaysia are a major threat to biodiversity due to habitat loss and alteration, affecting the populations of many waterbird species. This study was conducted to determine the spatial distribution of three stork species, the Asian Openbill Anastomus oscitans, Painted Stork Mycteria leucocephala and Milky Stork Mycteria cinerea, in Peninsular Malaysia using the citizen science database, eBird. About 86,881 occurrences of the Asian Openbill, 2,391 occurrences of the Painted Stork and 242 occurrences of the Milky Stork were identified in the eBird database throughout Peninsular Malaysia between 2019 and 2021, suggesting major differences in occurrence size between the three species. Map generated from ArcGIS and a statistically significant difference in the population distribution of the three stork species across Peninsular Malaysia indicate habitat segregation. The populations of these stork species should be carefully monitored and managed to avoid imbalance with other waterbird populations. [ABSTRACT FROM AUTHOR]

Proventricular dilatation disease (PDD) is caused by avian bornavirus (ABV) has been identified in psittacine, non-psittacine birds and waterfowl. Birds may show signs of gastrointestinal tract deficit or neurological dysfunction or even both. The objectives of this study were to determine the molecular prevalence, risk factors and public awareness of ABV and PDD among captive and non-captive birds in Peninsular Malaysia.

Abstract Orang Asli, the indigenous people of Peninsular Malaysia, is a minority population and placed behind in terms of socioeconomy, education and health. The Malaysian government has supported Orang Asli since the second Malaysia Plan in the 1970s, resulting in changes in their living standard, access to health, education and occupation. Hence, this review aims to assess the recent prevalence of diseases among Orang Asli in Peninsular Malaysia. The Preferred Reporting Items for Systematic Reviews and Meta-Analysis (PRISMA) review protocol guided this systematic review. The research question was formulated based on Population, Interest, Comparison and Outcome (PICO). The selected databases include Web of Science, Scopus, Ovid and EBSCOhost. The process of identification, screening and inclusion identified 33 articles. The mixed methods appraisal tool (MMAT) was then used to rank the quality of the articles. Selangor is the most frequent state involved in this review (12 studies), followed by Perak (10 studies), Pahang (10 studies) and Kedah (one study). We categorised into four categories of diseases, namely neglected tropical disease (n = 20), non-communicable disease (n = 6), nutritional status (n = 5), and hepatic disease (n = 2). The prevalence of diseases among Orang Asli is higher than in the general population, especially for soil-transmitted helminth (STH) and malnutrition. There is increasing research on non-communicable diseases due to an increasing trend in the socioeconomic status and lifestyle of the Orang Asli. Government agencies and private organisations must work together to empower Orang Asli with a healthy lifestyle, improve their socioeconomic status, and enhance food security, all of which will improve Orang Asli's health and reduce the prevalence of diseases.

The Amomum genus comprises of perennial, tropical, herbaceous plants that are distributed globally and possess both medicinal and ornamental properties. These plants contain a variety of secondary metabolites, including compounds with antioxidant and antimicrobial properties. This is the first transcriptomic analysis of seven Amomum species from Peninsular Malaysia, utilizing leaves, stems, and roots as sample material. Paired-end Illumina HiSeq technology was used for data generation which includes raw data, cleaned reads, de novo assembly, and functional annotation. The data is accessible via NCBI BioProject (PRJNA936673).

To date, documentation of the diversity of orchids from the limestone hills in the northern part of Peninsular Malaysia, particularly in the states of Kedah and Perak, is still lacking, with limited literature available. There is indeed an urgent need to fill this knowledge gap, so that proper documentation of the diversity of orchids from this unique karst habitat can be prepared. In this study, a series of 12 months of diversity assessments on five limestone hills in Kedah and Perak has resulted in the discovery of 56 orchid species from 37 genera. From this account, 12 species are new records within Kedah and 2 species are new records within Malaysia, namely Bulbophyllum meson J.J.Verm., Schuit. & de Vogel and Luisia brachystachys (Lindl.) Blume. Three species are endemic to Peninsular Malaysia which are Anoectochilus sanguineus P.T.Ong & P.O'Byrne, Cheirostylis goldschmidtiana Schltr. and Phalaenopsis appendiculata Carr. Findings of two keystone species, the long-lost Cheirostylis goldschmidtiana and the endangered snow-white slipper orchid, Paphiopedilum niveum (Rchb.f.) Stein, have catalyzed the need for a more comprehensive study to unveil the species richness and endemism within a limestone habitat. Heat maps using geographical data produced from ArcGIS software have enabled precise determination of the areas with the highest concentration of orchid diversity. Results from this study have shown that Gunung Fakir Terbang houses the greatest number of orchid species, followed by Gunung Batu Putih and Gunung Baling. Meanwhile, lower species occurrences were recorded from Gunung Pulai and Gunung Pong. However, lack of attention and delayed conservation action on this unique karst habitat would only lead to more habitat loss, leading to the decline of limestone orchid populations. Orchids as well as other plants are threatened by anthropogenic activity such as quarrying and forest clearing for agriculture. Thus, the results of this study will serve as baseline data for future work in documenting and conserving limestone orchids and their karst habitat in northern Peninsular Malaysia. [ABSTRACT FROM AUTHOR]

To remain competitive, rural tourism should be more proactive in commercializing its products given the challenging external environment. Similarly, homestay programme that offer unique tourism products have the potential to contribute to the socioeconomic development of the country. However, there are homestay programme that have experienced a decline in tourist visits due to a lack of innovation in marketing techniques. Hence, the objective of this study is to explore the impact of the marketing innovation implementation on homestay programme performance. To achieve the objective of the study, a qualitative research approach was used that included face-to-face interviews with homestay programme coordinators. A total of eight homestay programme in Peninsular Malaysia were selected based on several criteria. The results of these interviews were analyzed using content analysis techniques. The study shows that the marketing innovations implemented fall into three categories, namely participation in commercial programs, external agency ventures and the use of a digital medium. The innovation impacted the performance of the homestay programme in terms of increasing community involvement and achievement of homestay awards. The implications of this study contribute to the development of entrepreneurial knowledge by highlighting the importance of innovation and performance in rural tourism. The findings of this study are useful to industry stakeholders as a guide for commercialising homestay programme globally. [ABSTRACT FROM AUTHOR]

Global warming causes a temperature rise and alteration of other meteorological variables that directly or indirectly affect human comfort. The wet bulb globe temperature (WBGT) incorporates the effects of multiple meteorological variables to provide a reliable measure of human thermal stress. Despite the large significance of WBGT on public health, studies related to characterization and trends assessment of WBGT are limited in the tropical humid region like Peninsular Malaysia due to the unavailability of all meteorological variables required for such analysis. This study employed reanalysis meteorological data of ERA5 to assess the characteristics and changes in hourly, daily, monthly, seasonal and annual outdoor WBGT over peninsular Malaysia for the period 1959–2021 using the Liljegren method. The WBGT values were classified into five categories to assess the human thermal stress levels defined by the United States Department of the Army (USDA). The mean daily WBGT in PM varies from 21.5 °C in the central south elevated region to 30.5 °C in the western coastal region. It always reaches a heat-related illness risk level (31.20 °C) in the afternoon during monsoon and extreme stress conditions during inter-monsoonal periods. The trend analysis revealed an increase in WBGT for all the time scales. The higher increase in the mean and maximum WBGT was estimated in the coastal and south regions, nearly by 0.10 to 0.25 °C/decade. The increase in mean nighttime WBGT was 0.24 °C/decade, while in mean daytime WBGT was 0.11 °C/decade. The increase in WBGT caused a gradual expansion of areas experiencing daily WBGT exceeding a high-risk level for 5 h (11 AM to 3 PM). The information and maps generated in this study can be used for mitigation planning of heat-related stress risk in PM, where temperature extremes have grown rapidly in recent years. [ABSTRACT FROM AUTHOR]

Simple Summary: This study evaluated 26 sequences of terrapins worldwide through COI DNA barcoding and phylogenetic analysis, which included 12 species and three families. Moreover, 16 haplotypes were found; they were either misidentified, or a potential cryptic species was determined between B. baska and B. affinis affinis. Thus, COI remains an effective barcode marker for the terrapin species. Technological and analytical advances to study evolutionary biology, ecology, and conservation of the Southern River Terrapin (Batagur affinis ssp.) are realised through molecular approaches, including DNA barcoding. We evaluated the use of COI DNA barcodes in Malaysia's Southern River Terrapin population to better understand the species' genetic divergence and other genetic characteristics. We evaluated 26 sequences, including four from field specimens of Southern River Terrapins obtained in Bota Kanan, Perak, Malaysia, and Kuala Berang, Terengganu, Malaysia, as well as 22 sequences from global terrapins previously included in the Barcode of Life Database (BOLD) Systems and GenBank. The species are divided into three families: eight Geoemydidae species (18%), three Emydidae species (6%), and one Pelomedusidae species (2%). The IUCN Red List assigned the 12 species of terrapins sampled for this study to the classifications of critically endangered (CR) for 25% of the samples and endangered (EN) for 8% of the samples. With new haplotypes from the world's terrapins, 16 haplotypes were found. The intraspecific distance values between the COI gene sequences were calculated using the K2P model, which indicated a potential cryptic species between the Northern River Terrapin (Batagur baska) and Southern River Terrapin (Batagur affinis affinis). The Bayesian analysis of the phylogenetic tree also showed both species in the same lineage. The BLASTn search resulted in 100% of the same species of B. affinis as B. baska. The Jalview alignment visualised almost identical sequences between both species. The Southern River Terrapin (B. affinis affinis) from the west coast of Peninsular Malaysia was found to share the same haplotype (Hap_1) as the Northern River Terrapin from India. However, B. affinis edwardmolli from the east coast of Peninsular Malaysia formed Hap_16. The COI analysis found new haplotypes and showed that DNA barcodes are an excellent way to measure the diversity of a population. [ABSTRACT FROM AUTHOR]

Salt-licks are considered to be important places for conservation of animals; however, functions of salt-licks were still not well studied especially in Peninsular Malaysia. In order to examine the possible mineral-supplementing function of salt-licks of this area, we compared mineral concentration between the water from salt-licks mainly visited by herbivorous mammals to drink water and nearby streams, possible water sources for mammals at the area. We also analyzed the relationship between mineral concentration and salt-lick visit by mammals. Among analyzed minerals, only the concentrations of sodium and calcium were significantly higher in water from all studied salt-licks than those of nearby streams in both dry and rainy seasons, indicating that mammals could supplement these minerals by drinking salt-lick water. Herbivores most frequently visited the salt-lick with the sodium concentration significantly higher than other salt-licks. In contrast, omnivores and carnivores did not show such tendency. Red muntjac (Muntiacus muntjak) and sambar (Rusa unicolor), the first and second most-frequent visitors of salt-licks (41.7% and 20.8% of the visitation record by mammals, respectively), most frequently visited the salt-lick with highest sodium concentration. On the other hand, Malayan tapir (Tapirus indicus) and white-thighed langur (Presbytis siamensis), the third and fourth most-frequent visitors (15.1% and 5.4%, respectively), frequently visited the salt-lick with lower sodium concentration. The results are consistent with hypotheses that sodium supplementation is an important purpose of salt-lick visit by herbivores, and indicated that other factors which would vary by species, such as social interaction, also affect selection of salt-licks to visit by herbivores. [ABSTRACT FROM AUTHOR]

We present a regional thermal structure as well as a new crustal thickness model beneath the Peninsular Malaysia and the surrounding regions. Curie point depth estimates for the entire area range between ∼ 17 – 46 km with a mean of 29 km. The estimated crustal thickness for the study area varies from ∼ 28 – 35 km with an average of ∼ 31 km. Uplifted Curie depths (20 – 25 km) and deeper Moho depths (30 – 34 km) are observed over most parts of Peninsular Malaysia continent. In contrast, the NW Peninsular Malaysia continent and the southern Thailand are characterized by deeper Curie depths between 30 and 40 km. These regions with deeper Curie depths are coincident with the oldest dated rocks on the Sibumasu terrane. The observation of larger Curie depths in NW Peninsular Malaysia implies that the region is presently thermally stable than the remaining parts of the Peninsular. Consistent with deeper crustal thickness (30 – 35 km), the west Sumatra block yields the deepest Curie point depth that ranges between 30 and 46 km. The west Sumatra block and the NW Peninsular Malaysia have low Bouguer anomalies and comparable crustal thickness indicating similarity in regional features. This suggests that these regions are linked by a common ancient continental core. A comparison between the Curie depths and crustal thickness shows that the upper mantle beneath the Island of Sumatra, Singapore, Malay basin, NW Peninsular Malaysia continent, and southern Thailand are significantly magnetized.

Gridded rainfall datasets based on various data sources and techniques have emerged to help describe the spatiotemporal features of rainfall patterns over large areas and have gained popularity in many regional/global climatic analyses. This study explored future variations of rainfall characteristics over peninsula Malaysia and Singapore region based on rainfall indices of PRCPTOT, Rx1day, Rx5day, R95pTOT, R1mm, and R20mm, under 9 CORDEX-SEA RCM datasets with RCP8.5 emission scenario. A monthly quantile delta mapping method (MQDM) was adopted for bias-correction of the RCM modelled data. It was indicated that all the studied rainfall indices have long-term variations both temporally and spatially. Generally, the further the future, the higher the variability and uncertainty of indices. For the study region, the relative increments of the medians from RCM models averaged over all climatic zones in the far future are 40.3%, 25.9%, and 4.7% for Rx1day, Rx5day and R95pTOT, respectively. The annual rainfall amount (PRCPTOT) in the long run would likely increase mainly in the northeast coastal zone and drop in most of other areas over the peninsula, with the median being -5.9% averaged over all zones. The frequency of wet days (R1mm) would generally drop over the whole peninsula, with the median averaged over all zones being -6.8% in the far future. The frequency of heavy rains (R20mm) would overall decrease (by -3.4% in average in the far future) but might still notably increase in the northeast zone (NE) at both annual and southwest monsoon. The extreme conditions implied from individual RCM models could be more alarming. The study result could be useful in revealing the essential spatiotemporal variations of rainfall over the peninsula from short- to long-term futures and supporting large-scale flood risk assessment and adaptation planning. [ABSTRACT FROM AUTHOR]

Gigantochloa scortechinii Gamble, the most economically important wild bamboo species in Peninsular Malaysia, was recently known to hybridise with another common bamboo species, Dendrocalamus pendulus Ridl., in some areas where both species co-exist. In the present study, we reported a new locality (Sungai Siput, Perak) for this hybrid species, ×Gigantocalamus malpenensis K.M. Wong. We assessed the population genetic structure of the hybrid and parental populations in this new locality. Molecular studies were based on the DNA sequence data of two nuclear DNA markers, namely granule bound starch synthase I and cellulase-like protein 1 (PvCel1) genes. Genetic differentiation in these species and their population structures were inferred using network analysis, Bayesian phylogenetic analysis, population structure analysis, population pairwise FST analysis and principal coordinate analysis. We suggest that the hybrid population in Sungai Siput consists of only F1 individuals that were derived from multiple parental individuals. No significant genetic differentiation was detected between the hybridising and non-hybridising G. scortechinii, suggesting that the population structure of the parental populations may not be adversely affected by the occurrence of the new hybrid population. The hybrid population exhibits a considerably high degree of genetic variability, indicating non-uniformity in morphological and physiological properties in the hybrid individuals. Hence, there could be a wide range of choices for clone selection in silviculture. We anticipated opportunities for new hybrid populations to emerge, driven by the environmental factors and, therefore a promising continuous supply from the wild for this bamboo hybrid. [ABSTRACT FROM AUTHOR]

Context: We studied the virus component in the microbial food-web in the tropical coastal Sunda Shelf waters. Aims: We investigated viral processes, including the lysogenic to lytic shift dynamics with seawater warming and nutrient enrichment. Methods: We sampled nearshore and offshore waters of Peninsular Malaysia to provide a natural trophic gradient for correlational analyses. We also conducted laboratory experiments to investigate the changes in virus production rates and lysogeny, when temperature (range: 25–37°C) and nutrient concentrations (range: 0.1–1.0× marine-broth concentration) were manipulated. Key results: Observations showed site-dependent differences in dissolved inorganic nutrient concentration, Chl- a (0.21–3.54 μg L−1) and bacterial abundance (4.09 × 105−9.41 × 105 cells mL−1), but not in viral abundance (measured as virus-like particles or VLP) (1.04 × 106−2.39 × 106 VLP mL−1) and virus production rates (0.59 × 105−4.55 × 105 VLP mL−1 h−1). From laboratory experiments, both warming and nutrient enrichment increased virus production (R 2 > 0.651), decreased lysogeny (R 2 > 0.743), and resulted in an increase of the viral lysis:bacterial production ratio, and a stronger viral control on bacterial production. Conclusions: Although both seawater warming and nutrient enrichment increased virus production and reduced lysogeny, nutrient enrichment was a more important factor. Implications: The increasing nutrient concentrations in these waters will increase virus production and virus top-down control of bacteria, and drive the ecosystem towards heterotrophy. Tropical coastal waters are experiencing warming and nutrient enrichment, and these environmental changes increased both bacterial and virus production. Nutrient enrichment increased virus production and resulted in a stronger virus top-down control on bacterial production. Therefore, eutrophication will drive the ecosystem towards heterotrophy. [ABSTRACT FROM AUTHOR]

The emergence of potentially life-threatening zoonotic malaria caused by Plasmodium knowlesi nearly two decades ago has continued to challenge Malaysia healthcare. With a total of 376 P. knowlesi infections notified in 2008, the number increased to 2,609 cases in 2020 nationwide. Numerous studies have been conducted in Malaysian Borneo to determine the association between environmental factors and knowlesi malaria transmission. However, there is still a lack of understanding of the environmental influence on knowlesi malaria transmission in Peninsular Malaysia. Therefore, our study aimed to investigate the ecological distribution of human P. knowlesi malaria in relation to environmental factors in Peninsular Malaysia. A total of 2,873 records of human P. knowlesi infections in Peninsular Malaysia from 1st January 2011 to 31st December 2019 were collated from the Ministry of Health Malaysia and geolocated. Three machine learning-based models, maximum entropy (MaxEnt), extreme gradient boosting (XGBoost), and ensemble modeling approach, were applied to predict the spatial variation of P. knowlesi disease risk. Multiple environmental parameters including climate factors, landscape characteristics, and anthropogenic factors were included as predictors in both predictive models. Subsequently, an ensemble model was developed based on the output of both MaxEnt and XGBoost. Comparison between models indicated that the XGBoost has higher performance as compared to MaxEnt and ensemble model, with AUCROC values of 0.933 ± 0.002 and 0.854 ± 0.007 for train and test datasets, respectively. Key environmental covariates affecting human P. knowlesi occurrence were distance to the coastline, elevation, tree cover, annual precipitation, tree loss, and distance to the forest. Our models indicated that the disease risk areas were mainly distributed in low elevation (75–345 m above mean sea level) areas along the Titiwangsa mountain range and inland central-northern region of Peninsular Malaysia. The high-resolution risk map of human knowlesi malaria constructed in this study can be further utilized for multi-pronged interventions targeting community at-risk, macaque populations, and mosquito vectors. [ABSTRACT FROM AUTHOR]

A land snail checklist based on multiple collections between 2009 and 2011 on the Batu Caves limestone hill yielded a total of 48 species of land snails. Eight species are synanthropic and non-native, two are restricted to Selangor limestone hills and 11 are known only from Sgr 01 Batu Caves to date. This collection did not account for the 20 species reported from previous studies at Batu Caves. Systematic malacofaunal surveys are recommended for Batu Caves and all limestone hills in its vicinity to better understand endemism and biogeography of land snails on these hills. The ecological effects of activities like open burning, land clearing and infrastructure developments must be investigated to identify and mitigate threats to the land snail community on Batu Caves. [ABSTRACT FROM AUTHOR]

Oil palm is regarded as one of the most important crops in the tropics, contributing significantly to economy of Malaysia. The objective of this study is to model oil palm yield distributions and investigate the factors that influence oil palm yields in Peninsular Malaysia using remote sensing and geographical information system (GIS) techniques. Herein, we investigate six factors that influence oil palm yield in Peninsular Malaysia, including mean annual minimum and maximum temperatures, mean annual rainfall, average number of rainy days per year, average annual relative humidity, and elevation. In order to model oil palm yield in Peninsular Malaysia, a large yield dataset covering Peninsular Malaysia for 37 years (1983 to 2020), as well as related explanatory variables, were collected. Areal interpolation was used to model the average yield distribution across the study area. The findings of this study show that oil palm yields vary across Peninsular Malaysia. Due to favourable climate and elevation, southern and southwestern Peninsular Malaysia, including Johor, Pahang, Melaka, and Selangor, recorded the highest amount of yield. [ABSTRACT FROM AUTHOR]

Changes in the monsoon season rainfall over Peninsular Malaysia by the mid-21st century are examined using multi-model ensemble data from the CMIP6 HighResMIP experiments. We examine simulations of the present and future climate simulations run under a high emission scenario of greenhouse gases from the Shared Socioeconomic Pathways (SSP5-8.5). The combined effects of horizontal and vertical resolutions on the projected changes in monsoon rainfall and associated environmental fields are investigated by comparing the ensemble mean of the projected changes utilizing appropriate multi-model groupings. The results indicate a projected decrease (by up to 11% near Mersing of eastern Johor, for the period 2031–2050 relative to 1981–2000) in monsoon precipitation along the southeastern coast of Peninsular Malaysia during the northeast monsoon season associated with the projected weakening of the monsoon flow during boreal winter. For the northwestern regions (e.g. Perak) often affected by severe floods, a significant increase in precipitation (by up to 33%) is projected during the southwest monsoon season, partly driven by the projected strengthening of the cross-equatorial flow and the weakened low-level anti-cyclonic shear of winds in boreal summer. However, the magnitudes and signal-to-noise ratios of the projected changes vary considerably with respect to different horizontal and vertical resolutions. Firstly, models with relatively high horizontal and vertical resolutions project a more significant decrease in precipitation during the northeast monsoon season. Secondly, for the southwest monsoon season, models with relatively high horizontal resolutions project larger magnitudes of increases in precipitation over the northern region, while smaller increases are found in simulations with relatively high vertical resolutions. Generally, reduced ensemble spread and increased signal-to-noise ratios are found in simulations at higher horizontal and vertical resolutions, suggesting increased confidence in model projections with increased model resolution. [ABSTRACT FROM AUTHOR]

Potential Evapotranspiration (PET) functions as an indicator to estimate the amount of water loss to the atmosphere. Over the years, global climate change has eventually led to a change of PET capacity and this has affected the agricultural sector and water resource management. The objective of this study was to determine the best PET estimation method as well as to carry out a trend analysis and stationarity test of PET in Peninsular Malaysia. The Mann–Kendall (MK) test and Sen's slope estimator were applied for the trend analysis while the Augmented Dickey–Fuller (ADF) test and Kwiatkowski–Phillips–Schmidt–Shin (KPSS) test were applied for the stationarity test. The findings showed that Pulau Langkawi and Kuantan stations exhibited increasing trends while Bayan Lepas station exhibited decreasing trends for the daily, monthly, and annual PET time series. The daily, monthly, and annual PET time series at Bayan Lepas, Ipoh, Subang and Muadzam Shah stations were found to be stationary. Overall, the PET trend was found to be higher in the coastal regions and stationary in the mountainous region. HIGHLIGHTS The Mann–Kendall test and Sen's slope estimator were used to analyse the trends of potential evapotranspiration (PET) series.; The stationarity of PET series was evaluated using the Kwiatknowski–Phillips–Schmidt (KPSS) test.; The Turc method gave the best performances in estimating PET.; The coastal regions exhibited increasing PET trend.; The daily, monthly and annual PET trends in the mountainous region were stationary.;

Understanding of the climate-water nexus for sustainability, required good knowledge of the climate effects on groundwater aquifer units, particularly in rural communities. The studies were achieved using RES2-D modelling of the subsurface structures at the study site. Geophysical exploration with the application of 2-D Electrical Resistivity Imaging (ERI), combined with Induced Polarization (IP) method, were carried out to identify groundwater aquifers during extreme weather at Kampung Kuala Pajam, Beranang, Selangor, Peninsular Malaysia. The signatures obtained from geophysical explorations were used to better understand the phenomena that are responsible for groundwater depletion in the area. In recent times, there had been seasonal fluctuations in the water supply from boreholes serving the community. During the drought season, subsurface underlain this area experienced perennial acute shortages of groundwater supplies due to annual climatic variations that call for immediate solution by meeting the agricultural, domestic, and industrial water usage of the State of Selangor. A Pole-dipole techniques, using seven parallel lines of 400 m each at 5 m inter electrode spacing deployed to study the groundwater accumulation/aquifers within the area. Saturated groundwater occurrences zones were delineated as areas with average resistivity values of about 125 Ω-m, with corresponding chargeability of 30 ms. The methods used identified major faults along the northeast-southwest (NE-SW) directions, suitable for groundwater occurrences with approximate volume of about 2.86 Mega cubic metre (CBM), to proffer lasting solutions to the challenges being experienced by the community using a climate-water nexus sustainability.