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1.
It has long been assumed that the peat underlying tropical peat swamp forests accumulates because the extreme conditions (water logged, nutrient poor, anaerobic and acidic—pH 2.9–3.5) impede microbial activity. Litterbag studies in a tropical Malaysian peat swamp (North Selangor peat swamp forest) showed that although the sclerophyllous, toxic leaves of endemic peat forest plants (Macaranga pruinosa, Campnosperma coriaceum, Pandanus atrocarpus, Stenochlaena palustris) were barely decomposed by bacteria and fungi (decay rates of only 0.0006–0.0016 k day−1), leaves of M. tanarius, a secondary forest species were almost completely decomposed (decay rates of 0.0047–0.005 k day−1) after 1 year. Thus it is intrinsic properties of the leaves (that are adaptations to deter herbivory in the nutrient poor environment) that impede microbial breakdown. The water of the peat swamp was very high in dissolved organic carbon (70–84 mg l−1 DOC). Laboratory studies revealed initial rapid leaching of DOC from leaves (up to 1,720 mg l−1 from 4 g of leaves in 7 days), but the DOC levels then fell rapidly. The leaching of DOC resulted in weight loss but the physical structure of the leaves remained intact. It is suggested that the DOC is used as a substrate for microbial growth hence lowering the concentration of DOC in the water and transferring energy from the leaves to other trophic levels. This would explain how nutrient poor tropical peatswamps support diverse, abundant flora and fauna despite low nutrient levels and lack of rapid litter cycling such as occurs in other types of tropical rainforests.  相似文献   

2.
This paper presents quantitative data on blowpipe hunting among the Semaq Beri, a group of the aboriginal peoples of Peninsular Malaysia, with special reference to daily activity rhythms, space use, efforts, and efficiency of hunting. The role of hunting is examined in the diet of the population studied, which is in transition from a nomadic to a sedentary lifestyle. The special hunting focus on a few species (the leaf monkeys, Presbytis spp.) is examined in relation to ecology of prey items and using the optimal diet breadth model. Technological efficiencies of the Semaq Beri blowpipe and dart are compared with the Waorani of Ecuador.  相似文献   

3.
Damselfishes (Pomacentridae) are among the most common of reef fishes in tropical seas, comprising 320 species in all, with 268 species alone in the Indo-West Pacific regions. 15 genera (Abudefduf, Amblyglyphidodon, Amphiprion, Chelioprion, Chromis, Chrysiptera, Dascyllus, Pristotis, Dischistodus, Hemiglyphidodon, Neoglyphidodon, Neopomacentrus, Plectroglyphidodon, Pomacentrus, Stegastes) and at least 39 species inhabit the waters of Peninsular Malaysia and Singapore. They are important ecologically because many species are extremely abundant in reefs, and also economically, as several are collected in large numbers for the lucrative aquarium trade. This demand has led to some fishermen using destructive methods in obtaining the fishes, to the point that original standing populations may not be recoverable. This threat poses a need for conservation of the reefs. The present study based primarily on fishes collected from the waters of Singapore and specimens from the Zoological Reference Collection at the National University of Singapore, will serve the dual purpose of establishing a current species list for Malaysia and Singapore, and to update and clarify the local taxonomy of the group. An annotated list (with localities) is provided of the known or reported species to aid studies on reefs.  相似文献   

4.
Begonias are hyper-diverse and important horticultural plants. Six polymorphic microsatellite markers were developed from CT- and GT-enriched libraries of Begonia maxwelliana. The number of alleles per locus ranged from 2 to 12 and the observed heterozygosity ranged from 0.036 to 0.813. Null alleles were detected in one locus (Bma161) after Bonferroni correction. All the six markers were amplifiable in 23 selected Begonia species with the success rates of 17–100%. On average, species of the same section as B. maxwelliana (i.e. sect. Platycentrum) yielded higher transferability (91%). These markers will be useful for population genetic studies of the genus Begonia.  相似文献   

5.
Phylogenetic relationships were inferred for representative Bulbophyllum species of 13 sections from subtribe Bulbophyllinae (Epidendroideae, Orchidaceae) in Peninsular Malaysia. The combined data matrix consists of sequences from ITS nuclear gene region and trnL-F, matK, and rbcL plastid gene regions with 3114 characters. Molecular data were analysed using parsimony and Bayesian inference. The results show that several recognized sections are monophyletic. Section Hirtula with paraphyletic status must split up and section Desmosanthes contain misplaced elements. Furthermore, generic status of Cirrhopetalum and Epicrianthes cannot be supported, because they are deeply embedded within the genus Bulbophyllum. Section Desmosanthes is recognized as the closest group to section Cirrhopetalum; therefore, they can be merged in some aspects.  相似文献   

6.
The females among more than 7000 long-tailed macaques, Macaca fascicularis,that had recently been trapped for biomedical research were examined for pregnancy. The animals were taken from the wild in the north of Peninsular Malaysia during the period 1978 to 1979 and in the south from 1978 to 1982. Both samples showed some pregnancies in all months of the year and a peak during the months of May to July. Additional peaks in other months in some years showed that, while the midyear pregnancy peak was significant, it was not as marked a phenomenon as is the breeding peak in many other species. This might be due to the complexity and unpredictability of both the climate and the macaques’ food supply in Peninsular Malaysia. The additional peaks also illustrated the pitfalls of generalizing about breeding seasonality on the basis of small samples.  相似文献   

7.
The genetic structure of the locally threatened cyprinid Osteochilus melanopleurus, collected from four locations (Gerik, Manong, Bernam and Kahang) in Peninsular Malaysia River systems, was assessed based on partial sequences of the control region (D-loop) mitochondrial DNA. A partial D-loop of 364 base pair gene was extracted from 88 individuals through PCR amplification and direct sequencing. The results show that haplotype diversity (hd = 0.7956–0.9485) was high, with low nucleotide (π = 0.0045–0.0080) variation for each of the populations examined. A molecular variance analysis (AMOVA) revealed few differences between the four populations. A Tajima D test and Fu Fs test were used to investigate the neutrality of each population, revealing that the all examined populations might experience recent population expansion or the bottleneck effect. A phylogeny tree and mismatch distribution analysis provided further evidence that three of four populations had recently expanded, as well as indicating that the Kahang population had in contrast remained stable. Overall, this study concludes that the populations of O. melanopleurus distributed throughout the river systems of Peninsular Malaysia probably originated from a single ancestral source during the last glaciation period, and should therefore be treated as a single evolutionary unit in any conservation efforts.  相似文献   

8.
Bovine anaplasmosis is a major concern to cattle farming in most parts of the world. Anaplasmosis negatively impacts the profitability of cattle farming by reducing the production, reproduction, and draft ability of cattle. Here, we report results from a one-year cross sectional study to determine the epidemiology and the risk factors for Anaplasma marginale infection of cattle in Peninsular Malaysia. Examination of one thousand and forty five blood samples of apparently healthy cattle from forty-three farms in all the states of Peninsular Malaysia by polymerase chain reaction (PCR) assay revealed an overall prevalence of A. marginale infection of cattle of 72.6%, showing high endemicity of this heamoprotozoan among cattle in the country. Cattle breeds, production type, herd owner, herd size, management system, farm size, farm age, prophylactic treatment against blood parasites, presence of ticks, frequency of deticking, zones, closeness to forest, closeness to waste area, closeness to human settlement and closeness to body of water were the risk factors significantly associated (P?<?0.05) with the detection of A. marginale in cattle. Results of this first molecular study on the epidemiology and risk factors for A. marginale infection of cattle from all the states of Peninsular Malaysia suggest policies and strategies for the prevention and control of the parasite to improve profitability of cattle farming in the country.  相似文献   

9.
A comprehensive survey on large mammal diversity from a disturbed forest in Peninsular Malaysia has been carried out for over a period of 21 months. A total of 24 camera traps which accumulated to 5972 trap days. A total of 33 species 27 genera and 15 families of mammals were recorded via camera trapping and observations. The use of camera traps provides detailed information on diversity of some cryptic and secretive mammals. Secondary forest may support a wide diversity of mammals at a stable condition where intrusion, excision and fragmentation are reduced or avoided. The threats to mammals in the study are also discussed.  相似文献   

10.
This paper examines the question of whether hunter-gatherers could live in the tropical rain forest of Peninsular Malaysia without access to cultivated foods. It considers the wild food sources used by the Batek De', a contemporary foraging-trading group of Kelantan state, historical and ethnohistorical evidence concerning the Batek economy in the past, and archeological evidence for independent foraging in the Pleistocene and early Holocene. The conclusion reached is that small nomadic groups of foragers can live off wild resources alone in that environment and have done so in the past, although trade for agricultural produce makes life much easier. This suggests that nonseasonal tropical rain forests vary in their potential for supporting human foraging, depending upon the particular species of plants and animals present.  相似文献   

11.
Little is known about how arboreal arthropods respond to forest disturbance. We assessed how rain forest fragmentation affected the vertical stratification of arboreal dung beetles in Peninsular Malaysia. An arboreal dung beetle species (Onthophagus sp.) moved closer to the forest floor in smaller fragments, suggesting a downward shift in its foraging possibly in response to fragmentation.  相似文献   

12.
The biodiversity inhabiting tropical peat swamp forests in Southeast Asia is currently threatened by commercial logging and agricultural expansion. The occurrence of mammals in such forests is often poorly known and the factors influencing their occurrence in these ecosystems have rarely been quantified. We aim to determine the key habitat and landscape drivers of mammal species richness in fragmented peat swamp reserves. We conducted camera trap surveys in the North Selangor Peat Swamp Forest (NSPSF), the last remaining area of peat swamp forest on the west coast of Peninsular Malaysia. We also measured vegetation structure and landscape metrics to investigate the relationship between these factors and mammal richness. We recorded a total of 16 mammal species from 45 sampling sites using camera traps located in peat swamp forest reserves. Mammal species richness increased with the abundance of large trees and distance away from roads. Species richness decreased significantly with canopy cover and height, the abundance of fallen trees, the abundance of forest palms and saplings, distance away from rivers, and a measure of landscape compositional heterogeneity. Our findings underscore the high conservation value of logged peat swamp forests and the urgent need to halt further deforestation. We recommend: (1) protecting riparian habitat; (2) avoiding further forest conversion particularly areas supporting large trees into oil palm plantations; and (3) limiting road development within and around the NSPSF.  相似文献   

13.
The identification of larval fish has been an important morphological issue in marine biology due to the dramatic transformations that most species undergo from early larval stages to adulthood. Insufficient morphological diagnostic characters in larval fishes made it easy to misidentify them and a difficult process to key to genus and species level. The experiment aims to find out, by applying DNA barcoding, how consistent the morphological identifications can be among larval fish. Larval fish were mainly collected using plankton nets around mangrove areas in Pendas (Johor), Setiu (Terengganu), Pekan (Pahang) and Matang (Perak) Malaysia between April 2015 and October 2015. A total of 354 samples were morphologically identified, mostly to the family level and a few to the genus level. Larval fish ranged from 1.5 mm to 31 mm of total length, with the most abundant individuals being <3 mm. Among them, a total of 177 individuals were selected for DNA barcoding analyses. Molecular works involved polymerase chain reaction (PCR) and sequencing of mitochondrial Cytochrome c Oxidase I (COI) gene fragment (655 base pairs) methods. DNA barcoding enabled all samples to be identified down to species level. The overall genetic identities ranged from 91% to 100%. Morphological identification classified the specimens into 19 families and 11 genera while DNA barcoding identified them into 19 families 33 genera and 40 species. A comparison between the two methods showed a mismatched identification of 42.6% where the accuracy percentage for morphological identification was moderate for the family level (67.8%) but was low for genus level identification (30%). The DNA barcoding method also managed to successfully identify 86.4% of the samples up to their species level where morphological method has failed to do so. The most misidentified families in the study were Blenniidae, Sparidae, Apogonidae Ambassidae and Monachantidae while almost all samples from the family Gobiidae and Engraulidae were correctly identified to family level because of their distinct morphology. In conclusion, taxonomic studies of larval fish should continue using combination of both morphology and DNA barcoding methods. Morphological identification should be more conservative i.e., when in doubt, it is better to key only to family and not to the genus and species level. DNA barcoding is a better method for deeper taxonomic levels identification with the existence of robust sequence reference libraries and should be able to validate the accuracy of traditional larval fish identification.  相似文献   

14.
The perception that better information on environment and development is the determinant of effective rational decision- and policy-making processes provide the impetus for global interest in the use of sustainable development indicators (SDIs). Accordingly, proposals for SDIs are framed either on organisational goals or on disciplinary and multidisciplinary theories—aiming to reduce uncertainties in choosing the best alternative among a set of options concerning sustainability. Despite the fact that many SDI initiatives are explicitly aimed at improving policy-making, it is not apparent that political settings and organisational realities are taken into consideration in designing the framework for sustainability assessment. Ignoring the realities of policy-making dynamics can result in poor institutionalisation of the SDI development process, and therefore reduced impact of indicators. Linkage of SDIs to policy processes must also take into account the complex role of information in policy processes. The importance of societal values, cultural contexts and behaviour of bureaucracies must be understood and used to assist the assessment of progress towards sustainability using SDIs. Essentially, objective knowledge must be tampered with pragmatism in governance. This paper highlights the case of SDI development in the state of Selangor where the notion of instrumental rationality is balanced with the ‘incrementalism’ of the policy process that provided the foundation for institutionalising the reporting and use of SDIs. The ideals and paradoxes of participatory decision-making, the principles of the rational model and decision-making processes within a state government are critically examined.  相似文献   

15.
Four species of otters have been recorded from Malaysia and Singapore in the past: Lutra lutra (Common or Eurasian Otter), Lutra sumatrana (Hairy-nosed Otter), Lutrogale perspicillata (Smooth Otter) and Amblonyx cinereus (Oriental Small-clawed Otter). All four are listed in the Threatened Species Categories of the IUCN Red List of Threatened Animals: L. lutra is designated Vulnerable and the status of the other three Asian species are Insufficiently Known due to lack of information. From a review of the available literature and collation of museum records from Malaysia and Singapore, the past status of the four species are examined. Presently, only L. perspicillata and A. cinereus are common in Peninsular Malaysia where they are widely distributed, but both are rare in Singapore. L. sumatrana is rare but apparently still found in East Malaysia. It is possible that L. lutra did not range in Malaysia this century. Information about the habitat types, group size, range, diet and behaviour for all the species is poorly known. The available information allows a discussion of the Smooth and Small-clawed Otters only. This dearth of knowledge has hampered maintenance and breeding efforts of zoos and conservation activity.  相似文献   

16.
Rohan Pethiyagoda 《Hydrobiologia》1994,285(1-3):189-201
Sixty-two freshwater dispersant (26 endemic), 26 saltwater dispersant and 20 exotic fishes have been recorded from Sri Lanka's inland waters. The discovery of nine new species of freshwater fish during the past decade suggests that Sri Lanka's fish fauna is not yet well known and that further discoveries can be expected. All the new species, and almost all the endemic ones, have been recorded from forested areas in the foothills of the southwestern wet zone and the Knuckles hills. The known ranges of many species are exceedingly small; almost all of them are habitat specialists. 25 species have at least two strong habitat preferences (in almost all case, shade being one), though a majority (32 species) have none. Habitat alteration is therefore the greatest threat to their survival.Eight freshwater fish species are considered endangered and a further five, vulnerable. Three species are rare, 18 common and 13 abundant. All but two of the endangered species and all the vulnerable species are endemic in Sri Lanka. Nine species are each restricted to only one drainage basin, and seven have a known range < 50 km2. Three species of diadromous gobies known only from small populations are considered vulnerable.Examination of the existing threats suggest that deforestation, the widespread dispersion of exotics, pollution caused by agricultural chemicals and increasing pressure from the food fishery present the greatest threats to fish populations. While the endemic fishes are restricted to or most abundant in the wet zone, the overwhelming extent (> 95%) of Sri Lanka's nature reserve areas are in the dry zone. A programme to maintain self-sustaining captive populations of the endangered species is urgently necessary.  相似文献   

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Indigenous palm species of Peru are listed with data on their distribution patterns, ecology, frequency, density in the ecosystems, and conservation status. Peruvian palm flora includes 140 native species in 34 genera with the following distribution patterns: strictly Andean (17), Andean and Subandean (3), strictly Subandean (19), Subandean and Amazonian (20), strictly Amazonian (78), Amazonian and South peripheral (2), South peripheral (1). About 43% of the species occur at very low or low frequency in the country and about 9% are insufficiently known in situ for their conservation status to be defined. There are no Extinct species. Sixteen of the 17 strictly Andean palms are threatened species; 3 of them are Endangered, while only 5 strictly Subandean, 3 Subandean-Amazonian, and 4 strictly Amazonian palms are in these categories.  相似文献   

20.
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