Beta diversity - the variation in species composition among spatially discrete communities - and sampling grain - the size of samples being compared - may alter our perspectives of diversity within and between landscapes before and after agricultural conversion. Such assumptions are usually based on point comparisons, which do not accurately capture actual differences in total diversity. Beta diversity is often not rigorously examined. We investigated the beta diversity of ground-foraging ant communities in fragmented oil palm and forest landscapes in Sabah, Malaysia, using diversity metrics transformed from Hill number equivalents to remove dependences on alpha diversity. We compared the beta diversities of oil palm and forest, across three hierarchically nested sampling grains. We found that oil palm and forest communities had a greater percentage of total shared species when larger samples were compared. Across all grains and disregarding relative abundances, there was higher beta diversity of all species among forest communities. However, there were higher beta diversities of common and very abundant (dominant) species in oil palm as compared to forests. Differences in beta diversities between oil palm and forest were greatest at the largest sampling grain. Larger sampling grains in oil palm may generate bigger species pools, increasing the probability of shared species with forest samples. Greater beta diversity of all species in forest may be attributed to rare species. Oil palm communities may be more heterogeneous in common and dominant species because of variable community assembly events. Rare and also common species are better captured at larger grains, boosting differences in beta diversity between larger samples of forest and oil palm communities. Although agricultural landscapes support a lower total diversity than natural forests, diversity especially of abundant species is still important for maintaining ecosystem stability. Diversity in agricultural landscapes may be greater than expected when beta diversity is accounted for at large spatial scales.
Dengue fever (DF) is an urban vector-borne disease transmitted by Aedes aegypti and Aedes albopictus. Both species deposit their eggs in favorable breeding sites either in natural or artificial containers. An understanding of their habitat characteristics is crucial in curbing DF outbreaks
This study assessed the environmental impacts of the formulation of graphene oxide (GO)/multi-walled carbon nanotubes (MWCNTs) conductive membranes and of the process operating parameters of electrically-enhanced palm oil mill effluent (POME) filtration. Two different analyses approaches were employed, cradle-to-gate approach for conductive membrane production and gate-to-gate approach for the POME filtration process. The parameters in conductive-membrane formulation (e.g. the weight ratio of carbon nanomaterials, and concentration of GO/MWCNT nanohybrids) and process operating parameters (e.g. electric field strength and electricity operating mode) were investigated. The findings herein are twofold. Firstly, for the fabrication of GO/MWCNT conductive membranes, the best weight ratio of GO:MWCNTs was found to be 1:9, given its superior membrane electrical conductivity with lower environmental impacts by 8.51% compared to pristine MWCNTs. The most suitable concentration of carbon nanomaterials was found to be 5 wt%, given its lowest impacts on resource depletion, human health, and ecosystems. Secondly, for the electrically-enhanced POME filtration, the optimum process operating parameters were found to be the application of an electric field of 300 V/cm in the continuous mode, given its lower environmental impacts (22.99%-89.30%) secondary to its requirement of the least electricity to produce permeate. The present study has established not only the optimized conditions in membrane formulation but also the operating parameters of electrically-enhanced filtration; such findings enable the use of cleaner production and sustainable approach to minimize fouling for industrial applications, whilst maintaining excellent efficiency.
The Setiu Wetlands, a unique area with nine interconnected habitats, comprises a considerable fraction of the total Peninsular Malaysia's wetland flora. Although botanical collecting in the area has been active in the past 10 years, only a few studies dealing with the wetland flora have been published. Thus, a detailed checklist of this area is urgently needed to ensure the continuity of its inter-relating flora and fauna, as well as the livelihood of the local people. In this work we conducted a survey of the vascular plant flora of Setiu Wetlands and investigated the most important plants used by the local communities. Our checklist accounts for 406 taxa from 277 genera and 106 families, including 24 (6%) species of ferns and lycophytes, three gymnosperms, 257 (64%) dicotyledons and 122 (30%) monocotyledons. This comprehensive plant checklist will be a primary reference for the management of the newly gazetted Setiu Wetlands State Park covering more than 400 hectares of lands and water bodies.
Betta nuluhon, new species, is described from a hill stream habitat in western Sabah. This species is allied to both B. chini and B. balunga, and differs from rest of its congeners in the B. akarensis group in having the following combination of characters: yellow iris when live; mature males with greenish-blue iridescence on opercle when live; mature fish with distinct transverse bars on caudal fin; slender body (body depth 22.1-25.2 % SL); belly area with faint reticulate pattern (scales posteriorly rimmed with black); absence of tiny black spots on anal fin; lateral scales 29-31 (mode 30); predorsal scales 20-21 (mode 20). Notes on a fresh series of B. chini are also provided.
Microalgae-based bioproducts are in limelight because of their promising future, novel characteristics, the current situation of population needs, and rising prices of rapidly depleting energy resources. Algae-based products are considered as clean sustainable energy and food resources. At present, they are not commercialized due to their high production cost and low yield. In recent years, novel genome editing tools like RNAi, ZNFs, TALENs, and CRISPR/Cas9 are used to enhance the quality and quantity of the desired products. Genetic and metabolic engineering are frequently applied because of their rapid and precise results than random mutagenesis. Omic approaches help enhance biorefinery capabilities and are now in the developing stage for algae. The future is very bright for transgenic algae with increased biomass yield, carbon dioxide uptake rate, accumulating high-value compounds, reduction in cultivation, and production costs, thus reaching the goal in the global algal market and capital flow. However, microalgae are primary producers and any harmful exposure to the wild strains can affect the entire ecosystem. Therefore, strict regulation and monitoring are required to assess the potential risks before introducing genetically modified microalgae into the natural ecosystem.
Gunung Senyum Recreational Forest harbours 59 species, two subspecies and five varieties of mosses in 32 genera and 16 families that had been identified from a total of 589 specimens collected from the area. These figures represent 11.8% out of the 558 taxa, 20.2% out of the 158 genera and 34.7% out of the 46 families of mosses reported for Peninsular Malaysia. The total also represents 14.9% of the 442 taxa, 24.0% of the 133 genera and 40.0% of the 40 families of mosses recorded in Pahang. The largest family of mosses found in this limestone forest is Calymperaceae followed by Fissidentaceae. There are two new records for Pahang, Calymperespallidum Mitt. and Taxitheliumbinsteadii Broth. & Dixon. The analysis of species similarities of mosses found in the study area with some other selected areas showed that Gunung Senyum Recreational Forest had a high percentage of species similarity with Perlis State Park at Wang Kelian, another limestone forest, at 38%. Corticol is the main habitat utilised by mosses in Gunung Senyum Recreational Forest with 47 taxa, followed by the lignicol and calcicol each with 35 and 26 taxa, respectively.
Cobia Rachycentron canadum, is one of the emerging aquaculture species but is usually a non-target resource in fisheries
industry and within Malaysia, their landings are among the highest worldwide. Identification of stocks with unique
morphological characters is important for effective management and sustainable utilization. Morphometric variations
among three different cobia populations from Kedah, Terengganu and Johor were studied. All the morphometric
characteristics varied among the three populations as all the elements of the first Eigen vector were positive. Discriminant
analysis suggested that head depth (HD) and maximum body depth, (MaxD) were the most varied among the populations.
Cobia populations from Kedah and Johor were in a single cluster in the dendrogram with a 63.69% similarity while
Terengganu was in another cluster with a similarity of 8.01% from Kedah and Johor. The differences in the observed
morphometry may be resulted from different trophic activities and/or habitat productiveness explored by each of the
populations
Wide spread documentation of antibiotic pollution is becoming a threat to aquatic environment. Erythromycin (ERY), a macrolide belonging antibiotic is at the top of this list with its concentrations ranging between ng/L to a few μg/L in various global waterbodies giving rise to ERY-resistance genes (ERY-RGs) and ERY- resistance bacteria (ERY-RBs) posing serious threat to the aquatic organisms. ERY seems resistant to various conventional water treatments, remained intact and even increased in terms of mass loads after treatment. Enhanced oxidation potential, wide pH range, elevated selectivity, adaptability and greater efficiency makes advance oxidation processes (AOPs) top priority for degrading pollutants with aromatic rings and unsaturated bonds like ERY. In this manuscript, recent developments in AOPs for ERY degradation are reported along with the factors that affect the degradation mechanism. ERY, marked as a risk prioritized macrolide antibiotic by 2015 released European Union watch list, most probably due to its protein inhibition capability considered third most widely used antibiotic. The current review provides a complete ERY overview including the environmental entry sources, concentration in global waters, ERY status in STPs, as well as factors affecting their functionality. Along with that this study presents complete outlook regarding ERY-RGs and provides an in depth detail regarding ERY's potential threats to aquatic biota. This study helps in figuring out the best possible strategy to tackle antibiotic pollution keeping ERY as a model antibiotic because of extreme toxicity records.
Pygoluciola dunguna Nada, 2018 was described from Peninsular Malaysia, using males and reliably associated females. This paper details description of the larva which has been conclusively identified as Pygoluciola dunguna based on DNA barcoding technique and uses morphology, brief habitat and behavioural data. A total of 70 larval specimens were measured and their main features described. The larvae exhibit a riparian or semi-aquatic behaviour, observed crawling on the sandy edge of shallow streams. The stake-like projections along the length of the body suggest a form of defensive mechanism from falling prey to aquatic predators.
Tropical peat forests are a globally important reservoir of carbon, but little is known about CO2 exchange on an annual basis. We measured CO2 exchange between the atmosphere and tropical peat swamp forest in Sarawak, Malaysia using the eddy covariance technique over 4 years from 2011 to 2014. The CO2 fluxes varied between seasons and years. A small carbon uptake took place during the rainy season at the beginning of 2011, while a substantial net efflux of >600 g C/m2 occurred over a 2 month period in the middle of the dry season. Conversely, the peat ecosystem was a source of carbon during both the dry and rainy seasons in subsequent years and more carbon was lost during the rainy season relative to the dry season. Our results demonstrate that the forest was a net source of CO2 to the atmosphere during every year of measurement with annual efflux ranging from 183 to 632 g C m-2 year-1 , noting that annual flux values were sensitive to gap filling methodology. This is in contrast to the typical view of tropical peat forests which must have acted as net C sinks over time scales of centuries to millennia to create the peat deposits. Path analyses revealed that the gross primary productivity (GPP) and ecosystem respiration (RE) were primarily affected by vapour pressure deficit (VPD). Results suggest that future increases in VPD could further reduce the C sink strength and result in additional net CO2 losses from this tropical peat swamp forest in the absence of plant acclimation to such changes in atmospheric dryness.
Recent advances in environmental analytical chemistry have identified the presence of a large number of chemicals of emerging Arctic concern (CEACs) being transported long range to the region. There has been very limited temporal monitoring of CEACs and it is therefore unknown whether they are of increasing or decreasing concern. Likewise, information on potential biological adverse effects from CEACs on Arctic wildlife is lacking compared with legacy persistent organic pollutants (POPs) found at levels associated with health effects in marine mammals. Hence, there is a need to monitor CEACs along with POPs to support risk and regulatory CEAC assessments. We suggest pan-Arctic temporal trend studies of CEACs in wildlife including the establishment of toxicity thresholds to evaluate their potential effects on populations, biodiversity, and ecosystem services.
During a taxonomic revision of species in the genus Stegonotus Duméril et al., 1854, we re-examined over 90% of all known museum specimens from this taxon. Of the five specimens available to us from the island of Borneo, three are clearly distinct from the other two. The latter are from the lowland rainforest in Sarawak, Malaysia, which includes the type locality of S. borneensis, and therefore these specimens retain that name. We here describe the other three, which include the paratype of S. borneensis, as a new species from Sabah, Malaysia. The new species can be differentiated from S. borneensis and all other species of Stegonotus by the combination of a high number of ventrals ( 210) combined with a low number of subcaudals ( 70), a short tail (indicated by a low subcaudal ratio of 0.25), 17-17-15 dorsal scale rows, a snout-scale ratio of 1/4-1/3, the "gull wing +" condition of the rostral, the number of supralabials touching the eye, and a dorsal color pattern featuring a dark gray-brown head offset from a lighter-brown rest of the body. The number of subcaudals in the holotype of the new species is only 21% of the number of ventrals, the lowest proportion in the genus. The new species is found at elevations above 1000 m in the cool, montane habitats of the Crocker Range and around the foot of Mt. Kinabalu, Southeast Asia's tallest mountain, from where it has been known but taxonomically unrecognized since at least the 1880s.
The genus Senyumia was previously known from a single species, S.minutiflora (Ridl.) Kiew, A.Weber & B.L.Burtt, from a limestone karst, Gunung Senyum, in Pahang, Malaysia. Senyumiagranitica Kiew, here described and illustrated, is the second species of the genus. It differs from S.minutiflora, not only in its habitat, but also in its shorter leaves, larger, non-resupinate or only partially resupinate flowers and smaller seeds. It is known from a small, fragmented population from a low range of hills. Therefore, under the IUCN Red List Categories & Criteria, it is assessed as Critically Endangered.
This study aims to assess the environmental impacts of conventional and organic rice cultivations and proposes a sustainable conceptual framework of rice farming based on the life cycle assessment (LCA) approach. A cradle-to-gate LCA was performed by using the ReCiPe 2016 method and SimaPro 8.5 software. The functional unit was one ton of rice grains harvested. Primary data were obtained from the farmer, while secondary data were collected from Ecoinvent 3.0, the Agri Footprint 3.0 database and the literature. The total characterization factors for global warming potential (GWP), water consumption potential (WCP) and fossil fuel depletion potential (FFP) were 457.89 kg CO2-eq, 98.18 m3 and 84.56 kg oil-eq, respectively, at the midpoint level for conventional rice, while the impacts for organic rice were 140.55 kg CO2-eq, 29.45 m3 and 22.25 kg oil-eq, respectively. At the endpoint level, the total characterization factors for human health damage (HH), ecosystem damage (ED) and resource availability (RA) for conventional rice were 9.63 × 10-4 DALY, 5.54 × 10-6 species.year and 30.98 Dollar, respectively, while for organic rice, the impacts were 2.60 × 10-4 DALY, 2.28 × 10-6 species.year and 8.44 Dollar, respectively. Rice cultivation impacted the environment, particularly in relation to three impact categories: GWP, WCP and FFP. The cultivation phase of rice production was the main contributor to environmental impacts due to the production and application of fertilizer and pesticides. It can be concluded that the application of LCA in agricultural sector is able to provide information and responses for policy makers in understanding the potential environmental impacts at various spatial levels.
Soil respiration is the largest carbon efflux from the terrestrial ecosystem to the atmosphere, and selective logging influences soil respiration via changes in abiotic (temperature, moisture) and biotic (biomass, productivity, quantity and quality of necromass inputs) drivers. Logged forests are a predominant feature of the tropical forest landscape, their area exceeding that of intact forest. We quantified both total and component (root, mycorrhiza, litter, and soil organic matter, SOM) soil respiration in logged (n = 5) and old-growth (n = 6) forest plots in Malaysian Borneo, a region which is a global hotspot for emission from forest degradation. We constructed a detailed below-ground carbon budget including organic carbon inputs into the system via litterfall and root turnover. Total soil respiration was significantly higher in logged forests than in old-growth forests (14.3 ± 0.23 and 12.7 ± 0.60 Mg C ha-1 year-1 , respectively, p = 0.037). This was mainly due to the higher SOM respiration in logged forests (55 ± 3.1% of the total respiration in logged forests vs. 50 ± 3.0% in old-growth forests). In old-growth forests, annual SOM respiration was equal to the organic carbon inputs into the soil (difference between SOM respiration and inputs 0.18 Mg C ha-1 year-1 , with 90% confidence intervals of -0.41 and 0.74 Mg C ha-1 year-1 ), indicating that the system is in equilibrium, while in logged forests SOM respiration exceeded the inputs by 4.2 Mg C ha-1 year-1 (90% CI of 3.6 and 4.9 Mg C ha-1 year-1 ), indicating that the soil is losing carbon. These results contribute towards understanding the impact of logging on below-ground carbon dynamics, which is one of the key uncertainties in estimating emissions from forest degradation. This study demonstrates how significant perturbation of the below-ground carbon balance, and consequent net soil carbon emissions, can persist for decades after a logging event in tropical forests.
Need for regional economic development and global demand for agro-industrial commodities have resulted in large-scale conversion of forested landscapes to industrial agriculture across South East Asia. However, net emissions of CO2 from tropical peatland conversions may be significant and remain poorly quantified, resulting in controversy around the magnitude of carbon release following conversion. Here we present long-term, whole ecosystem monitoring of carbon exchange from two oil palm plantations on converted tropical peat swamp forest. Our sites compare a newly converted oil palm plantation (OPnew) to a mature oil palm plantation (OPmature) and combine them in the context of existing emission factors. Mean annual net emission (NEE) of CO2 measured at OPnew during the conversion period (137.8 Mg CO2 ha-1 year-1 ) was an order of magnitude lower during the measurement period at OPmature (17.5 Mg CO2 ha-1 year-1 ). However, mean water table depth (WTD) was shallower (0.26 m) than a typical drainage target of 0.6 m suggesting our emissions may be a conservative estimate for mature plantations, mean WTD at OPnew was more typical at 0.54 m. Reductions in net emissions were primarily driven by increasing biomass accumulation into highly productive palms. Further analysis suggested annual peat carbon losses of 24.9 Mg CO2 -C ha-1 year-1 over the first 6 years, lower than previous estimates for this early period from subsidence studies, losses reduced to 12.8 Mg CO2 -C ha-1 year-1 in the later, mature phase. Despite reductions in NEE and carbon loss over time, the system remained a large net source of carbon to the atmosphere after 12 years with the remaining 8 years of a typical plantation's rotation unlikely to recoup losses. These results emphasize the need for effective protection of tropical peatlands globally and strengthening of legislative enforcement where moratoria on peatland conversion already exist.
Invasive pathogens can be a threat when they affect human health, food production or ecosystem services, by displacing resident species, and we need to understand the cause of their establishment. We studied the patterns and causes of the establishment of the pathogen Dickeya solani that recently invaded potato agrosystems in Europe by assessing its invasion dynamics and its competitive ability against the closely related resident D. dianthicola species. Epidemiological records over one decade in France revealed the establishment of D. solani and the maintenance of the resident D. dianthicola in potato fields exhibiting blackleg symptoms. Using experimentations, we showed that D. dianthicola caused a higher symptom incidence on aerial parts of potato plants than D. solani, while D. solani was more aggressive on tubers (i.e. with more severe symptoms). In co-infection assays, D. dianthicola outcompeted D. solani in aerial parts, while the two species co-existed in tubers. A comparison of 76 D. solani genomes (56 of which have been sequenced here) revealed balanced frequencies of two previously uncharacterized alleles, VfmBPro and VfmBSer , at the vfmB virulence gene. Experimental inoculations showed that the VfmBSer population was more aggressive on tubers, while the VfmBPro population outcompeted the VfmBSer population in stem lesions, suggesting an important role of the vfmB virulence gene in the ecology of the pathogens. This study thus brings novel insights allowing a better understanding of the pattern and causes of the D.solani invasion into potato production agrosystems, and the reasons why the endemic D. dianthicola nevertheless persisted.
Indonesia is the second-largest contributor of microplastics (MPs) pollution in the marine ecosystem. Most MPs pollution-related studies in Indonesia focus on seawater, sediment, with less information found on the commercially important fish species used for human consumption. Skipjack Tuna (Euthynnus affinis) is one of the major exporting fishery commodities from Indonesia. This exploratory study aimed to determine MPs presence in the digestive tract of Skipjack Tuna from the Southern Coast of Java, Indonesia. The fish samples were collected from five different fish traditional auction market along the Southern Coast of Java, Indonesia, namely Pangandaran, Pamayang Sari, Ciletuh, Santolo, and Palabuhan Ratu. The gastrointestinal tract of Skipjack tuna was pretreated using alkaline destruction and filtered. The presence of MPs in the treated samples was visually identified using an optical microscope, while Polybrominated diphenyl ethers (PBDEs) contaminants were analyzed using Gas Chromatography-Mass Spectrometry (GC-MS). A total of 19 suspected MPs particles were found in the form of filament (84%), angular (11%), and round (5%). This result would provide a better indication of the MPs contamination in marine life species in the Southern Coast of Java, Indonesia, as useful information for marine environmental monitoring program in the future.
Soil hardness plays a vital role in evaluating the physical properties of soil structure. With regards to the impact of compaction on practical forest management issues, most report and review forms were available. Thus, the aim of this study was to evaluate the soil condition in riparian forest restoration planted with indigenous species along Kayan Ulu River with special reference to soil hardness. Soil hardness was measured by using Hasegawa-type cone penetrometer from the surface soils to 100 cm depth, with a total of 48 random points for both study sites surveyed; restoration sites planted with Shorea macrophylla in year 1996 and 1998 (SPD96 and SPD98, respectively) for both on and between planting lines. Our findings indicated that, soil hardness in SPD98 was harder as compared to SPD96 at shallow depth presented in one drop penetrability. Likewise, soil penetration resistance on planting line in SPD98 was significantly higher than SPD96 at surface soils (0-20 cm) and subsurface soils (20-40 cm). A high number of strikes and soil penetration resistance indicate that the soils were highly compacted. However, there was no significant difference in term of soil penetration resistance between planting line. In order to avoid effects on tree productivity, it is recommended that in future, the evaluation of soil hardness should be determined during the early establishment for future restoration of riparian ecosystem.