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South And Southeast Asia (south + and_southeast_asia)
Selected AbstractsMid-Holocene and glacial-maximum vegetation geography of the northern continents and AfricaJOURNAL OF BIOGEOGRAPHY, Issue 3 2000I. Colin Prentice Abstract BIOME 6000 is an international project to map vegetation globally at mid-Holocene (6000 14C yr bp) and last glacial maximum (LGM, 18,000 14C yr bp), with a view to evaluating coupled climate-biosphere model results. Primary palaeoecological data are assigned to biomes using an explicit algorithm based on plant functional types. This paper introduces the second Special Feature on BIOME 6000. Site-based global biome maps are shown with data from North America, Eurasia (except South and Southeast Asia) and Africa at both time periods. A map based on surface samples shows the method's skill in reconstructing present-day biomes. Cold and dry conditions at LGM favoured extensive tundra and steppe. These biomes intergraded in northern Eurasia. Northern hemisphere forest biomes were displaced southward. Boreal evergreen forests (taiga) and temperate deciduous forests were fragmented, while European and East Asian steppes were greatly extended. Tropical moist forests (i.e. tropical rain forest and tropical seasonal forest) in Africa were reduced. In south-western North America, desert and steppe were replaced by open conifer woodland, opposite to the general arid trend but consistent with modelled southward displacement of the jet stream. The Arctic forest limit was shifted slighly north at 6000 14C yr bp in some sectors, but not in all. Northern temperate forest zones were generally shifted greater distances north. Warmer winters as well as summers in several regions are required to explain these shifts. Temperate deciduous forests in Europe were greatly extended, into the Mediterranean region as well as to the north. Steppe encroached on forest biomes in interior North America, but not in central Asia. Enhanced monsoons extended forest biomes in China inland and Sahelian vegetation into the Sahara while the African tropical rain forest was also reduced, consistent with a modelled northward shift of the ITCZ and a more seasonal climate in the equatorial zone. Palaeobiome maps show the outcome of separate, independent migrations of plant taxa in response to climate change. The average composition of biomes at LGM was often markedly different from today. Refugia for the temperate deciduous and tropical rain forest biomes may have existed offshore at LGM, but their characteristic taxa also persisted as components of other biomes. Examples include temperate deciduous trees that survived in cool mixed forest in eastern Europe, and tropical evergreen trees that survived in tropical seasonal forest in Africa. The sequence of biome shifts during a glacial-interglacial cycle may help account for some disjunct distributions of plant taxa. For example, the now-arid Saharan mountains may have linked Mediterranean and African tropical montane floras during enhanced monsoon regimes. Major changes in physical land-surface conditions, shown by the palaeobiome data, have implications for the global climate. The data can be used directly to evaluate the output of coupled atmosphere-biosphere models. The data could also be objectively generalized to yield realistic gridded land-surface maps, for use in sensitivity experiments with atmospheric models. Recent analyses of vegetation-climate feedbacks have focused on the hypothesized positive feedback effects of climate-induced vegetation changes in the Sahara/Sahel region and the Arctic during the mid-Holocene. However, a far wider spectrum of interactions potentially exists and could be investigated, using these data, both for 6000 14C yr bp and for the LGM. [source] Origins and population genetics of weedy red rice in the USAMOLECULAR ECOLOGY, Issue 21 2007J. P. LONDO Abstract Weedy red rice (Oryza sativa spontonea) is a persistent and problematic weed of rice culture worldwide. A major hypothesis for the mechanism of production of this weed in South and Southeast Asia is hybridization between cultivated rice (Oryza sativa) and wild rice (Oryza rufipogon). However, weedy red rice can often be found outside the range of O. rufipogon leaving questions on the origin and process behind weedy rice infestations. In the USA, weedy red rice was first documented as early as 1846 and has continued to affect rice production areas. In this study, we attempt to identify the origin and population structure of weedy red rice sampled from the USA using both DNA sequence data from a neutral nuclear locus as well as microsatellite genotype data. Results suggest that two major accessions of weedy rice exist, strawhull and blackhull, and these forms may both hybridize with the cultivated rice of the USA, O. sativa japonica. Using population assignment of multilocus genotype signatures with principal component analysis and structure, an Asian origin is supported for US weedy rice. Additionally, hybridization between strawhull and blackhull varieties was inferred and may present the opportunity for the production of new weedy forms in the future. [source] Molecular characterization of the CP gene and 3,UTR of Chilli veinal mottle virus from South and Southeast AsiaPLANT PATHOLOGY, Issue 3 2008W. S. Tsai Twenty-four isolates of Chilli veinal mottle virus (ChiVMV) from China, India, Indonesia, Taiwan and Thailand were analysed to determine their genetic relatedness. Pathogenicity of virus isolates was confirmed by induction of systemic mosaic and/or necrotic ringspot symptoms on Capsicum annuum after mechanical inoculation. The 3, terminal sequences of the viral genomic RNA were determined. The coat protein (CP) coding regions ranged from 858 to 864 nucleotides and the 3, untranslated regions (3,UTR) from 275 to 289 nucleotides in length. All isolates had the inverted repeat sequence GUGGNNNCCAC in the 3,UTR. The DAG motif, conserved in aphid-transmitted potyviruses, was observed in all isolates. All 24 isolates were considered as belonging to ChiVMV because of their high CP amino acid and nucleotide identity (more than 94·8 and 89·5%, respectively) with the reported ChiVMV isolates including the pepper vein banding virus (PVBV), the chilli vein-banding mottle virus (CVbMV) and the CVbMV Chiengmai isolate (CVbMV-CM1). Based on phylogenetic analysis, ChiVMV isolates including all 24 isolates tested, PVBV, CVbMV and CVbMV-CM1 can be classified into three groups. In addition, a conserved region of 204 amino acids with more than 90·2% identity was identified in the C terminal of the CP gene of ChiVMV and Pepper veinal mottle virus (PVMV), and may explain the serological cross reaction between these two viruses. The conserved region may also provide useful information for developing transgenic resistance to both ChiVMV and PVMV. [source] Synanthropic primates in Asia: Potential sentinels for environmental toxinsAMERICAN JOURNAL OF PHYSICAL ANTHROPOLOGY, Issue 3 2010Gregory Engel Abstract Macaques are similar to humans both physiologically and behaviorally. In South and Southeast Asia they are also synanthropic, ecologically associated with humans. Synanthropy with humans raises the possibility that macaques come into contact with anthropogenic toxicants, such as lead and mercury, and might be appropriate sentinels for human exposures to certain toxic materials. We measured lead (Pb) and mercury (Hg) levels and characterized the stable isotopic compositions of ,15N and ,13C in hair from three groups of free-ranging macaques at the Swoyambhu temple in Kathmandhu, Nepal, an urban population that has abundant contact with humans. Hair lead levels were significantly higher among young macaques and differed among the three groups of macaques that were sampled. Hair Hg levels were low. No statistical association was found between stable isotopic compositions (,15N and ,13C) and Pb and Hg levels. Our data did not find evidence that lead levels were associated with diet. We conclude that, in this population of macaques, behavioral and/or physiologic factors may play a significant role in determining exposure to lead. Chemical analysis of hair is a promising, noninvasive technique for determining exposure to toxic elements in free-ranging nonhuman primates. Am J Phys Anthropol, 2010. © 2009 Wiley-Liss, Inc. [source] Exploring cultural drivers for wildlife trade via an ethnoprimatological approach: a case study of slender and slow lorises (Loris and Nycticebus) in South and Southeast AsiaAMERICAN JOURNAL OF PRIMATOLOGY, Issue 10 2010K.A.I. Nekaris Abstract Illegal and unsustainable trade in wildlife is a major conservation challenge. For Asian primates, economic and cultural traditions, and increased forest access mean that trade may have become detrimental for certain species. Slow and slender lorises (Nycticebus and Loris) are primates particularly prevalent in trade, determined until now by focused counts of lorises in regional markets. Here, we use international trade statistics and a participant,observer approach to assess culturally specific drivers for trade in lorises in South and Southeast Asia, to provide a broader context to help mitigate this practice. Analysis of international records for the last 30 years revealed that live animal trade was more prevalent than trade in body parts (slow lorises, 86.4%; slender lorises, 91.4%), with Laos, Cambodia, and Thailand the largest exporters. We then examine drivers of international and domestic trade based on long-term data from 1994,2009 in Sri Lanka, Cambodia, and Indonesia. We show that slender lorises are important in Sri Lankan folklore, but their use as pets and for traditional medicine is rare. Trade in Bengal slow and pygmy lorises in Cambodia for use in traditional medicines, a practice with deeply historical roots, is widespread. Despite its own set of myths about the magical and curative properties of lorises, trade in Javan, Bornean, and greater slow lorises in Indonesia is largely for pets. Conservation practices in Asia are often generalized and linked with the region's major religions and economies. We show here that, in the case of wildlife trade, culturally specific patterns are evident among different ethnic groups, even within a country. Revealing such patterns is the foundation for developing conservation management plans for each species. We suggest some participatory methods for each country that may aid in this process. Am. J. Primatol. 72:877,886, 2010. © 2010 Wiley-Liss, Inc. [source] Child Labour: a survey of selected Asian countriesASIAN-PACIFIC ECONOMIC LITERATURE, Issue 2 2004Ranjan Ray While the African continent has the highest child labour force participation rates, Asia contains the largest pool of child workers. The nature, magnitude and decline in child labour vary sharply between Asian countries. East Asia now has little child labour; however, child labour continues to have a significant presence in South Asia and in parts of Southeast Asia. This paper surveys the literature on child labour in selected Asian countries, paying special attention to its causes and consequences. The evidence presented shows that Asian child labour, especially in South and Southeast Asia, has some common features. For example, the bulk of child labour is in the 10,14 years age group. The phenomenon is largely rural, and child domestic labour constitutes a significant share. The participation rate of Asian children in the 15,17 years age group in economic activities, 48.4 per cent, is the highest in the world. There is a significant gender element in Asian child labour with boys outnumbering girls in economically active work, while the reverse is the case with domestic child labour. A focus of the survey is the empirical findings that provide insights into the policy instruments that may be needed in combating this phenomenon. The survey also discusses some of the important international and national initiatives that have been taken to reduce child labour. [source] Effect of betel chewing, tobacco smoking and alcohol consumption on oral submucous fibrosis: a case,control study in Sri LankaJOURNAL OF ORAL PATHOLOGY & MEDICINE, Issue 4 2006A. Ariyawardana Background:, Oral submucous fibrosis (OSMF) is a chronic, insidious, disabling potentially malignant condition of the oral mucosa seen predominantly in south and Southeast Asia. No reports are hitherto available on the aetiological factors of OSMF based on Sri Lankan patients. Methods:, A total of 74 patients with OSMF and 74 controls who consecutively attended the Oral Medicine clinic at the Dental Hospital (Teaching) Faculty of Dental Sciences, University of Peradeniya, Sri Lanka were included in the study. Binary logistic regression analyses were performed to model the influence of betel chewing, smoking and alcohol use and to determine the effects of different combinations of chewing habits on OSMF. Results:, Betel chewing was the only significantly associated factor in the aetiology of OSMF (OR = 171.83, 95% CI: 36.35,812.25). There were no interaction effects of chewing, smoking and alcohol consumption in the causation of OSMF. Conclusion:, The present study has shown a strong association of betel quid chewing (including tobacco as an ingredient) with the causation of OSMF. [source] | ||||||||||