Displaying publications 81 - 100 of 996 in total

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  1. Aziz AT, Dieng H, Ahmad AH, Mahyoub JA, Turkistani AM, Mesed H, et al.
    Asian Pac J Trop Biomed, 2012 Nov;2(11):849-57.
    PMID: 23569860 DOI: 10.1016/S2221-1691(12)60242-1
    To investigate the prevalence of container breeding mosquitoes with emphasis on the seasonality and larval habitats of Aedes aegypti (Ae. aegypti) in Makkah City, adjoining an environmental monitoring and dengue incidence.
    Matched MeSH terms: Ecosystem
  2. Aziz SA, Clements GR, Peng LY, Campos-Arceiz A, McConkey KR, Forget PM, et al.
    PeerJ, 2017;5:e3176.
    PMID: 28413729 DOI: 10.7717/peerj.3176
    There is an urgent need to identify and understand the ecosystem services of pollination and seed dispersal provided by threatened mammals such as flying foxes. The first step towards this is to obtain comprehensive data on their diet. However, the volant and nocturnal nature of bats presents a particularly challenging situation, and conventional microhistological approaches to studying their diet can be laborious and time-consuming, and provide incomplete information. We used Illumina Next-Generation Sequencing (NGS) as a novel, non-invasive method for analysing the diet of the island flying fox (Pteropus hypomelanus) on Tioman Island, Peninsular Malaysia. Through DNA metabarcoding of plants in flying fox droppings, using primers targeting the rbcL gene, we identified at least 29 Operationally Taxonomic Units (OTUs) comprising the diet of this giant pteropodid. OTU sequences matched at least four genera and 14 plant families from online reference databases based on a conservative Least Common Ancestor approach, and eight species from our site-specific plant reference collection. NGS was just as successful as conventional microhistological analysis in detecting plant taxa from droppings, but also uncovered six additional plant taxa. The island flying fox's diet appeared to be dominated by figs (Ficus sp.), which was the most abundant plant taxon detected in the droppings every single month. Our study has shown that NGS can add value to the conventional microhistological approach in identifying food plant species from flying fox droppings. At this point in time, more accurate genus- and species-level identification of OTUs not only requires support from databases with more representative sequences of relevant plant DNA, but probably necessitates in situ collection of plant specimens to create a reference collection. Although this method cannot be used to quantify true abundance or proportion of plant species, nor plant parts consumed, it ultimately provides a very important first step towards identifying plant taxa and spatio-temporal patterns in flying fox diets.
    Matched MeSH terms: Ecosystem
  3. Azman A, Ng KK, Ng CH, Lee CT, Tnah LH, Zakaria NF, et al.
    Sci Rep, 2020 11 05;10(1):19112.
    PMID: 33154411 DOI: 10.1038/s41598-020-76092-4
    Worldwide, many mangrove species are experiencing significant population declines, including Rhizophora apiculata, which is one of the most widespread and economically important species in tropical Asia. In Malaysia, there has been an alarming decline in R. apiculata populations driven primarily by anthropogenic activities. However, the lack of genetic and demographic information on this species has hampered local efforts to conserve it. To address these gaps, we generated novel genetic information for R. apiculata, based on 1,120 samples collected from 39 natural populations in Peninsular Malaysia. We investigated its genetic diversity and genetic structure with 19 transcriptome and three nuclear microsatellite markers. Our analyses revealed a low genetic diversity (mean He: 0.352) with significant genetic differentiation (FST: 0.315) among populations of R. apiculata. Approximately two-third of the populations showed significant excess of homozygotes, indicating persistent inbreeding which might be due to the decrease in population size or fragmentation. From the cluster analyses, the populations investigated were divided into two distinct clusters, comprising the west and east coasts of Peninsular Malaysia. The western cluster was further divided into two sub-clusters with one of the sub-clusters showing strong admixture pattern that harbours high levels of genetic diversity, thus deserving high priority for conservation.
    Matched MeSH terms: Ecosystem*
  4. Azman AS, Othman I, Velu SS, Chan KG, Lee LH
    Front Microbiol, 2015;6:856.
    PMID: 26347734 DOI: 10.3389/fmicb.2015.00856
    Actinobacteria are one of the most important and efficient groups of natural metabolite producers. The genus Streptomyces have been recognized as prolific producers of useful natural compounds as they produced more than half of the naturally-occurring antibiotics isolated to-date and continue as the primary source of new bioactive compounds. Lately, Streptomyces groups isolated from different environments produced the same types of compound, possibly due to frequent genetic exchanges between species. As a result, there is a dramatic increase in demand to look for new compounds which have pharmacological properties from another group of Actinobacteria, known as rare actinobacteria; which is isolated from special environments such as mangrove. Recently, mangrove ecosystem is becoming a hot spot for studies of bioactivities and the discovery of natural products. Many novel compounds discovered from the novel rare actinobacteria have been proven as potential new drugs in medical and pharmaceutical industries such as antibiotics, antimicrobials, antibacterials, anticancer, and antifungals. This review article highlights the latest studies on the discovery of natural compounds from the novel mangrove rare actinobacteria and provides insight on the impact of these findings.
    Matched MeSH terms: Ecosystem
  5. Azman NM, Zainudin MS, Sah SA, Latip NS
    Trop Life Sci Res, 2013 Dec;24(2):51-64.
    PMID: 24575248 MyJurnal
    Taman Negara Pulau Pinang (Penang National Park) is the only site on Pulau Pinang that supports a large population of the White-bellied Sea-eagle (WBSE) Haliaeetus leucogaster; however, the nesting sites of WBSEs have not been widely studied. As information on the location of WBSE nesting sites is very important for conservation works by local authorities, the objective of this study was to determine the distribution of nesting WBSEs in the coastal dipterocarp forest of Penang National Park. Surveys were conducted from December 2007 to July 2008 and October 2008 to April 2009, covering the breeding season of the species (September-July). The nesting sites were observed by boat along the coastline of Penang National Park and by performing ground surveys along the seashore at accessible areas; the nest survey was conducted three days/month from 0900 to 1500. A total of 34 WBSE nesting sites was located. Most of the occupied nests (seven nests) were found at Muka Head and Pantai Kerachut areas, which exhibit the densest concentration of occupied WBSE habitat in Penang National Park. WBSEs preferred to build their nests around Muka Head, which could be due to the frequent occurrence of whirlpools in the water body around that area. Aquatic animals, such as sea snakes and fish, stunned by the whirlpools would emerge to the sea surface, facilitating the foraging and feeding of WBSEs. Our results indicate that it is important to maintain and improve areas of suitable nesting habitat for WBSEs. Management actions should include (1) the yearly monitoring of known breeding sites throughout Penang National Park during the breeding season to determine breeding success over time, (2) recognising the critical habitat or nest-site selection of WBSEs, (3) establishment of a buffer zone surrounding nesting sites and potential habitat from human disturbance, and (4) encouraging on-going research to further understand this species.
    Matched MeSH terms: Ecosystem
  6. Azman NM, Latip NS, Sah SA, Akil MA, Shafie NJ, Khairuddin NL
    Trop Life Sci Res, 2011 Dec;22(2):45-64.
    PMID: 24575217 MyJurnal
    The diversity and the feeding guilds of birds in three different habitats (secondary forest, oil palm plantation and paddy field) were investigated in riparian areas of the Kerian River Basin (KRB), Perak, Malaysia. Point-count observation and mist-netting methods were used to determine bird diversity and abundance. A total of 132 species of birds from 46 families were recorded in the 3 habitats. Species diversity, measured by Shannon's diversity index, was 3.561, 3.183 and 1.042 in the secondary forest, the paddy field and the oil palm plantation, respectively. The vegetation diversity and the habitat structure were important determinants of the number of bird species occurring in an area. The relative abundance of the insectivore, insectivore-frugivore and frugivore guilds was greater in the forest than in the monoculture plantation. In contrast, the relative abundance of the carnivore, granivore and omnivore guilds was higher in the plantation. The results of the study show that the conversion of forest to either oil palm plantation or paddy fields produced a decline in bird diversity and changes in the distribution of bird feeding guilds.
    Matched MeSH terms: Ecosystem
  7. Azmi MA, Mokhtar K, Osnin NA, Razali Chan S, Albasher G, Ali A, et al.
    Environ Res, 2023 Dec 01;238(Pt 1):117074.
    PMID: 37678506 DOI: 10.1016/j.envres.2023.117074
    Coastal ecosystems play an important part in mitigating the effects of climate change. Coastal ecosystems are becoming more susceptible to climate change impacts due to human activities and maritime accidents. The global shipping industry, especially in Southeast Asia, has witnessed numerous accidents, particularly involving passenger ferries, resulting in injuries and fatalities in recent years. In order to mitigate the impact of climate change on coastal ecosystems, this study aimed to evaluate the relationship between employees' perceptions of safety criteria and their own safety behaviour on Langkawi Island, Malaysia. A straightforward random sampling technique was employed to collect data from 112 ferry employees aboard Malaysian-registered passenger boats by administering questionnaires. The findings shed light on the strong connection between providing safety instructions for passengers and safety behaviour among ferry workers. Safety instructions should contain climate-related information to successfully address the effects of climate change. The instructions might include guidance on responding to extreme weather events and understanding the potential consequences of sea-level rise on coastal communities. The ferry company staff should also expand their safe behaviour concept to include training and preparation for climate-related incidents. The need to recognise the interconnectedness between climate change, ferry safety and the protection of coastal ecosystems is emphasised in this study. The findings can be utilised by policymakers, regulatory agencies and ferry operators to design holistic policies that improve safety behaviour, minimise maritime mishaps and preserve the long-term sustainability of coastal ecosystems in the face of difficulties posed by climate change.
    Matched MeSH terms: Ecosystem*
  8. Azmiera N, Low VL, Heo CC
    Acta Parasitol, 2021 Jun;66(2):706-709.
    PMID: 33389626 DOI: 10.1007/s11686-020-00313-z
    INTRODUCTION: Psychoda sp. is often collected from patchy habitats such as sewers, drains and decomposing organic matters. The discovery of Psychoda sp. in forensic studies indicated that it might have noteworthy value in assisting death investigations.

    PURPOSE: This study reports on the first finding of Psychoda larvae collected from decomposing rabbit carcasses placed in Cameron Highlands, Pahang, Malaysia.

    METHODS: The larvae were first observed on rabbit carcasses and were collected using tweezers and carefully preserved in 70% ethanol. They were subsequently mounted on microscopy slides using Hoyer's medium and identified as Psychoda sp. morphologically. The identification was also confirmed through a DNA barcoding analysis.

    RESULTS: Psychoda sp. larvae were collected on day-10 post-mortem where the rabbit carcasses were at the advanced decay stage of decomposition. The cytochrome c oxidase I (COI) gene sequences of the larvae had 90% similarity with the Psychoda spp. in the database.

    CONCLUSION: The finding of these larvae on carrion may provide additional valuable insights into forensic entomology and may assist in death investigations.

    Matched MeSH terms: Ecosystem
  9. Azmy SN, Sah SA, Shafie NJ, Ariffin A, Majid Z, Ismail MN, et al.
    Sci Rep, 2012;2:524.
    PMID: 22826802 DOI: 10.1038/srep00524
    Population surveys and species recognition for roosting bats are either based on capture, sight or optical-mechanical count methods. However, these methods are intrusive, are tedious and, at best, provide only statistical estimations. Here, we demonstrated the successful use of a terrestrial Light Detection and Ranging (LIDAR) laser scanner for remotely identifying and determining the exact population of roosting bats in caves. LIDAR accurately captured the 3D features of the roosting bats and their spatial distribution patterns in minimal light. The high-resolution model of the cave enabled an exact count of the visibly differentiated Hipposideros larvatus and their roosting pattern within the 3D topology of the cave. We anticipate that the development of LIDAR will open up new research possibilities by allowing researchers to study roosting behaviour within the topographical context of a cave's internal surface, thus facilitating rigorous quantitative characterisations of cave roosting behaviour.
    Matched MeSH terms: Ecosystem
  10. Azrina MZ, Yap CK, Rahim Ismail A, Ismail A, Tan SG
    Ecotoxicol Environ Saf, 2006 Jul;64(3):337-47.
    PMID: 15964072
    A study of the impacts of anthropogenic activities on the distribution and biodiversity of benthic macroinvertebrates and water quality of the Langat River (Peninsular Malaysia) was conducted. Four pristine stations from the upstream and 4 stations at the downstream receiving anthropogenic impacts were selected along the river. For 4 consecutive months (March-June 1999), based on the Malaysian DOE (Malaysia Environmental Quality Report 2000, Department of Environment, Ministry of Science, Technology and Environment Malaysia. Maskha Sdn. Bhd. Kuala Lumpur, 86pp; Malaysia Environmental Quality Report 2001, Department of Environment, Ministry of Science, Technology and the Environment Malaysia) water quality index classes, the upstream stations recorded significantly (P<0.05) higher Biological Monitoring Working Party scores and better water quality indices than those of the downstream. The total number of macrobenthic taxa and their overall richness indices and diversity indices were significantly (P<0.05) higher at the upstream stations (54 taxa) than at the downstream stations (5 taxa). The upstream of the Langat River was dominated by Ephemeroptera and chironomid dipterans while other orders found in small quantities included Trichoptera, Diptera, Plecoptera, Odonata, Ephemeraptera, Coleoptera, and Gastropoda. On the other hand, the downstream of the river was mainly inhabited by the resistant Oligochaeta worms Limnodrilus spp. and Branchiodrilus sp. and Hirudinea in small numbers. The relationships between the physicochemical and the macrobenthic data were investigated by Pearson correlation analysis and multiple stepwise regression analysis. These statistical analyses showed that the richness and diversity indices were generally influenced by the total suspended solids and the conductivity of the river water. This study also highlighted the impacts of anthropogenic land-based activities such as urban runoff on the distribution and species diversity of macrobenthic invertebrates in the downstream of the Langat River. The data obtained in this study supported the use of the bioindicator concept for Malaysian rivers. Some sensitive (Trichopteran caddisflies and Ephemeraptera) and resistant species (Oligochaeta such as Limnodrilus spp.) are identified as potential bioindicators of clean and polluted river ecosystems, respectively, for Malaysian rivers.
    Matched MeSH terms: Ecosystem*
  11. Azwar E, Chan DJC, Kasan NA, Rastegari H, Yang Y, Sonne C, et al.
    J Hazard Mater, 2022 02 15;424(Pt A):127329.
    PMID: 34601414 DOI: 10.1016/j.jhazmat.2021.127329
    Aquatic weeds pose hazards to aquatic ecosystems and particularly the aquatic environment in shellfish aquaculture due to its excessive growth covering entire freshwater bodies, leading to environmental pollution particularly eutrophication intensification, water quality depletion and aquatic organism fatality. In this study, pyrolysis of six aquatic weed types (wild and cultured species of Salvinia sp., Lemna sp. and Spirodella sp.) were investigated to evaluate its potential to reduce and convert the weeds into value-added chemicals. The aquatic weeds demonstrated high fixed carbon (8.7-47.3 wt%), volatile matter content (39.0-76.9 wt%), H/C ratio (1.5-2.0) and higher heating value (6.6-18.8 MJ/kg), representing desirable physicochemical properties for conversion into biofuels. Kinetic analysis via Coats-Redfern integral method obtained different orders for chemical reaction mechanisms (n = 1, 1.5, 2, 3), activation energy (55.94-209.41 kJ/mol) and pre-exponential factor (4.08 × 104-4.20 × 1017 s-1) at different reaction zones (zone 1: 150-268 °C, zone 2: 268-409 °C, zone 3: 409-600 °C). The results provide useful information for design and optimization of the pyrolysis reactor and establishment of the process condition to dispose this environmentally harmful species.
    Matched MeSH terms: Ecosystem*
  12. B. Mabel Manjaji Matsumoto, Muhammad Ali Syed Hussein, Yee, Jean-Chai
    MyJurnal
    The central and north west coast of Sabah lies along the western extremity of the Coral Triangle, within which are situated several marine protected areas (MPAs). In the present study we determined in situ coral reef fish populations in several localities along the west coast of Sabah, by exploring species abundance, richness and diversity of ten economically important fish species. The underwater surveys were conducted from May to December 2015. During this eight- month period, surveys at each site were undertaken once every two months. Dives were conducted during the daylight hours. A total of 171 individuals from the targeted fish species were enumerated from the 349 still images and 220 minutes of video footage. Abundance was observed mainly in the semi-protected MPA (n=110) with only one fish species recorded with more than 2 individuals at protected MPA and unprotected sites. We observed a correlation between fish species richness and coral topographic complexity, with study sites at the semi-protected MPA having the most complex topography landscape, and accordingly recording the highest Shannon-Wiener index (H= 2.85). Higher abundance recorded at study sites in the unprotected sites and semi-protected MPA indicate that such areas could potentially become de facto MPAs. A long-term monitoring, assessment and evaluation of the multiple degrees of variables involved such as length-weight relationship, type of habitat, variation in depth, and species behaviour are recommended in order to understand better the relationship and dynamics between these variables.
    Matched MeSH terms: Ecosystem
  13. Bagchi R, Press MC, Scholes JD
    Ecol Lett, 2010 Jan;13(1):51-9.
    PMID: 19849708 DOI: 10.1111/j.1461-0248.2009.01397.x
    One important hypothesis to explain tree-species coexistence in tropical forests suggests that increased attack by natural enemies near conspecific trees gives locally rare species a competitive advantage. Host ranges of natural enemies generally encompass several closely related plant taxa suggesting that seedlings should also do poorly around adults of closely related species. We investigated the effects of adult Parashorea malaanonan on seedling survival in a Bornean rain forest. Survival of P. malaanonan seedlings was highest at intermediate distances from parent trees while heterospecific seedlings were unaffected by distance. Leaf herbivores did not drive this relationship. Survival of seedlings was lowest for P. malaanonan, and increased with phylogenetic dissimilarity from this species, suggesting that survival of close relatives of common species is reduced. This study suggests that distance dependence contributes to species coexistence and highlights the need for further investigation into the role of shared plant enemies in community dynamics.
    Matched MeSH terms: Ecosystem
  14. Bahuguna A, Singh A
    Mitochondrial DNA B Resour, 2019 Oct 17;4(2):3085-3091.
    PMID: 33365866 DOI: 10.1080/23802359.2019.1667270
    Oriental giant squirrels are tree squirrels classified under family Ratufinae. In India, there are three species of genus Ratufa, i.e. Ratufa bicolor, Ratufa macroura and Ratufa indica. They are also distributed in South and Southeast Asia. However Ratufa indica is endemic to India. The fourth species Ratufa affinis is restricted to Maritime Southeast Asia (East Malaysia, Indonesia, Brunei and Thailand) and probably in Singapore. The species is near threatened .The species R.macroura is endemic to South Asia. Forests of South and Southeast Asia are hotspots of squirrel diversity but at the same time they are at a high risk of extinction because of high deforestation rate and habitat fragmentation. The present molecular study is the first study of the species of Ratufa for their identification. In this study old taxidermy samples were used for amplification of 12SrRNA and Cytochrome b genes. Maximum likelihood and neighbor-joining methods were used to delineate the species by using MEGA 6 and also for molecular analysis for variable, conserved, parsimony and singleton sites. Similarities between species through BLAST indicated 92.21-89.57% between R.macroura vs. R. bicolour; 93.22-90% Ratufa macroura vs. Ratufa indica; 96-92% Ratufa indica vs. Ratufa bicolour, 93.88% between Ratufa affinis vs. Ratufa indica, 93.5% R. affinis vs. R. bicolor, 90.5%. R. affinis vs. R. macroura. Ratufa bicolor is noted to be genetically closer to R. indica as inferred by using both markers. The BLAST result indicated that the obtained sequences matched 99-100% with their respective species. It was also noted that R. bicolor of Jalpaiguri, West Bengal are genetically closer to that of Bhutan. The study also revealed the evolution of R. indica and R. macroura from a single population.
    Matched MeSH terms: Ecosystem
  15. Baldeck CA, Kembel SW, Harms KE, Yavitt JB, John R, Turner BL, et al.
    Oecologia, 2016 10;182(2):547-57.
    PMID: 27337965 DOI: 10.1007/s00442-016-3686-2
    While the importance of local-scale habitat niches in shaping tree species turnover along environmental gradients in tropical forests is well appreciated, relatively little is known about the influence of phylogenetic signal in species' habitat niches in shaping local community structure. We used detailed maps of the soil resource and topographic variation within eight 24-50 ha tropical forest plots combined with species phylogenies created from the APG III phylogeny to examine how phylogenetic beta diversity (indicating the degree of phylogenetic similarity of two communities) was related to environmental gradients within tropical tree communities. Using distance-based redundancy analysis we found that phylogenetic beta diversity, expressed as either nearest neighbor distance or mean pairwise distance, was significantly related to both soil and topographic variation in all study sites. In general, more phylogenetic beta diversity within a forest plot was explained by environmental variables this was expressed as nearest neighbor distance versus mean pairwise distance (3.0-10.3 % and 0.4-8.8 % of variation explained among plots, respectively), and more variation was explained by soil resource variables than topographic variables using either phylogenetic beta diversity metric. We also found that patterns of phylogenetic beta diversity expressed as nearest neighbor distance were consistent with previously observed patterns of niche similarity among congeneric species pairs in these plots. These results indicate the importance of phylogenetic signal in local habitat niches in shaping the phylogenetic structure of tropical tree communities, especially at the level of close phylogenetic neighbors, where similarity in habitat niches is most strongly preserved.
    Matched MeSH terms: Ecosystem
  16. Banin LF, Raine EH, Rowland LM, Chazdon RL, Smith SW, Rahman NEB, et al.
    Philos Trans R Soc Lond B Biol Sci, 2023 Jan 02;378(1867):20210090.
    PMID: 36373930 DOI: 10.1098/rstb.2021.0090
    Current policy is driving renewed impetus to restore forests to return ecological function, protect species, sequester carbon and secure livelihoods. Here we assess the contribution of tree planting to ecosystem restoration in tropical and sub-tropical Asia; we synthesize evidence on mortality and growth of planted trees at 176 sites and assess structural and biodiversity recovery of co-located actively restored and naturally regenerating forest plots. Mean mortality of planted trees was 18% 1 year after planting, increasing to 44% after 5 years. Mortality varied strongly by site and was typically ca 20% higher in open areas than degraded forest, with height at planting positively affecting survival. Size-standardized growth rates were negatively related to species-level wood density in degraded forest and plantations enrichment settings. Based on community-level data from 11 landscapes, active restoration resulted in faster accumulation of tree basal area and structural properties were closer to old-growth reference sites, relative to natural regeneration, but tree species richness did not differ. High variability in outcomes across sites indicates that planting for restoration is potentially rewarding but risky and context-dependent. Restoration projects must prepare for and manage commonly occurring challenges and align with efforts to protect and reconnect remaining forest areas. The abstract of this article is available in Bahasa Indonesia in the electronic supplementary material. This article is part of the theme issue 'Understanding forest landscape restoration: reinforcing scientific foundations for the UN Decade on Ecosystem Restoration'.
    Matched MeSH terms: Ecosystem*
  17. Barathan M, Ng SL, Lokanathan Y, Ng MH, Law JX
    Int J Mol Sci, 2024 Mar 07;25(6).
    PMID: 38542054 DOI: 10.3390/ijms25063080
    This paper sheds light on the alarming issue of antibiotic resistance (ABR) in aquatic environments, exploring its detrimental effects on ecosystems and public health. It examines the multifaceted role of antibiotic use in aquaculture, agricultural runoff, and industrial waste in fostering the development and dissemination of resistant bacteria. The intricate interplay between various environmental factors, horizontal gene transfer, and bacterial extracellular vesicles (BEVs) in accelerating the spread of ABR is comprehensively discussed. Various BEVs carrying resistance genes like blaCTX-M, tetA, floR, and sul/I, as well as their contribution to the dominance of multidrug-resistant bacteria, are highlighted. The potential of BEVs as both a threat and a tool in combating ABR is explored, with promising strategies like targeted antimicrobial delivery systems and probiotic-derived EVs holding significant promise. This paper underscores the urgency of understanding the intricate interplay between BEVs and ABR in aquatic environments. By unraveling these unseen weapons, we pave the way for developing effective strategies to mitigate the spread of ABR, advocating for a multidisciplinary approach that includes stringent regulations, enhanced wastewater treatment, and the adoption of sustainable practices in aquaculture.
    Matched MeSH terms: Ecosystem*
  18. Barrett RL
    Ann Bot, 2013 Apr;111(4):499-529.
    PMID: 23378523 DOI: 10.1093/aob/mct008
    BACKGROUND: Sedges (Cyperaceae) form an important ecological component of many ecosystems around the world. Sword and rapier sedges (genus Lepidosperma) are common and widespread components of the southern Australian and New Zealand floras, also occurring in New Caledonia, West Papua, Borneo, Malaysia and southern China. Sedge ecology is seldom studied and no comprehensive review of sedge ecology exists. Lepidosperma is unusual in the Cyperaceae with the majority of species occurring in dryland habitats.

    SCOPE: Extensive review of ecological literature and field observations shows Lepidosperma species to be important components of many ecosystems, often dominating understorey and sedge-rich communities. For the first time, a detailed ecological review of a Cyperaceae genus is presented.

    CONCLUSIONS: Lepidosperma species are long-lived perennials with significant abundance and persistence in the landscape. Speciation patterns in the genus are of considerable interest due to complex biogeographical patterns and a high degree of habitat specificity. Potential benefits exist for medicinal products identified from several Lepidosperma species. Over 178 organisms, including 26 mammals, 42 birds, six reptiles, five amphibians, eight arachnids, 75 insects, three crustaceans and 13 fungi, are found to be dependent on, or making use of, Lepidosperma species. A significant relationship exists between Lepidosperma species and the moth genus Elachista. Implications for the conservation and ecology of both sedges and associated species are discussed.

    Matched MeSH terms: Ecosystem
  19. Bates SS, Hubbard KA, Lundholm N, Montresor M, Leaw CP
    Harmful Algae, 2018 11;79:3-43.
    PMID: 30420013 DOI: 10.1016/j.hal.2018.06.001
    Some diatoms of the genera Pseudo-nitzschia and Nitzschia produce the neurotoxin domoic acid (DA), a compound that caused amnesic shellfish poisoning (ASP) in humans just over 30 years ago (December 1987) in eastern Canada. This review covers new information since two previous reviews in 2012. Nitzschia bizertensis was subsequently discovered to be toxigenic in Tunisian waters. The known distribution of N. navis-varingica has expanded from Vietnam to Malaysia, Indonesia, the Philippines and Australia. Furthermore, 15 new species (and one new variety) of Pseudo-nitzschia have been discovered, bringing the total to 52. Seven new species were found to produce DA, bringing the total of toxigenic species to 26. We list all Pseudo-nitzschia species, their ability to produce DA, and show their global distribution. A consequence of the extended distribution and increased number of toxigenic species worldwide is that DA is now found more pervasively in the food web, contaminating new marine organisms (especially marine mammals), affecting their physiology and disrupting ecosystems. Recent findings highlight how zooplankton grazers can induce DA production in Pseudo-nitzschia and how bacteria interact with Pseudo-nitzschia. Since 2012, new discoveries have been reported on physiological controls of Pseudo-nitzschia growth and DA production, its sexual reproduction, and infection by an oomycete parasitoid. Many advances are the result of applying molecular approaches to discovering new species, and to understanding the population genetic structure of Pseudo-nitzschia and mechanisms used to cope with iron limitation. The availability of genomes from three Pseudo-nitzschia species, coupled with a comparative transcriptomic approach, has allowed advances in our understanding of the sexual reproduction of Pseudo-nitzschia, its signaling pathways, its interactions with bacteria, and genes involved in iron and vitamin B12 and B7 metabolism. Although there have been no new confirmed cases of ASP since 1987 because of monitoring efforts, new blooms have occurred. A massive toxic Pseudo-nitzschia bloom affected the entire west coast of North America during 2015-2016, and was linked to a 'warm blob' of ocean water. Other smaller toxic blooms occurred in the Gulf of Mexico and east coast of North America. Knowledge gaps remain, including how and why DA and its isomers are produced, the world distribution of potentially toxigenic Nitzschia species, the prevalence of DA isomers, and molecular markers to discriminate between toxigenic and non-toxigenic species and to discover sexually reproducing populations in the field.
    Matched MeSH terms: Ecosystem
  20. Beaucournu JC, Wells K
    Parasite, 2009 Dec;16(4):283-7.
    PMID: 20092059
    We report on fleas collected from small mammals in a lower mountane rainforest in the Crocker Range National Park, Sabah, Borneo. Macrostylophora durdeni n. sp., collected from Dremomys everetti and, of minor importance, Tupaia montana, is described. Further records include Gryphopsylla jacobsoni segragata and Lentistivalius vomerus from T. montana.
    Matched MeSH terms: Ecosystem
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