10 resultados para East Asia flora

em Indian Institute of Science - Bangalore - Índia


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Eclogites from paragneiss in the Korean Peninsula are characterized by a peak pressure assemblage of garnet + omphacite + quartz + rutile, that is overprinted by multiphase symplectites involving augite, amphibole, orthopyroxene, ilmenite and plagioclase and by a similar high-pressure assemblage with a pronounced absence of the omphacite component in clinopyroxene formed during the peak and orthopyroxene in the retrograde stage. Eclogites were metamorphosed at a minimum pressures of not, vert, similar 20–23 kbar at temperatures of not, vert, similar 840–1000 °C, equivalent to a crustal depth of not, vert, similar 70–75 km, whereas high-pressure granulite in Late Paleozoic rocks underwent metamorphic conditions of not, vert, similar 18–19 kbar at not, vert, similar 950 °C with a minimum crustal depth of not, vert, similar 60–65 km. The presence of the eclogites and high-pressure granulite suggests deep-seated subduction of crustal complexes with metamorphism at different crustal levels. The eclogites were exhumed quickly resulting in near- isothermal decompression. On the other hand, the multistage exhumation of the high-pressure granulites suggests retrograde overprinting after initial decompression. The similarity of these petrological characteristics, metamorphic conditions and also the regional structural styles with those of the Sulu belt (China) strongly suggests the existence of a Permo-Triassic Alpine-type “Korean collision belt” in Far East Asia. This model provides a better understanding of the paleogeograpic evolution of Permo-Triassic East Asia, including a robust tectonic correlation of the Korean collision belt with the Qinling–Dabie–Sulu collision belt.

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Community-based natural resource management (CBNRM) is the joint management of natural resources by a community based on a community strategy, through a participatory mechanism involving all legitimate stakeholders. The approach is community-based in that the communities managing the resources have the legal rights, the local institutions and the economic incentives to take substantial responsibility for sustained use of these resources. This implies that the community plays an active role in the management of natural resources, not because it asserts sole ownership over them, but because it can claim participation in their management and benefits for practical and technical reasons1–4. This approach emerged as the dominant conservation concept in the late 1970s and early 1980s, of the disillusionment with the developmental state. Governments across South and South East Asia, Africa and Latin America have adopted and implemented CBNRM in various ways, viz. through sectoral programmes such as forestry, irrigation or wildlife management, multisectoral programmes such as watershed development and efforts towards political devolution. In India, the principle of decentralization through ‘gram swaraj’ was introduced by Mahatma Gandhi. The 73rd and 74th constitution amendments in 1992 gave impetus to the decentralized planning at panchayat levels through the creation of a statutory three-level local self-government structure5,6. The strength of this book is that it includes chapters by CBNRM advocates based on six seemingly innovative initiatives being implemented by nongovernmental organizations (NGOs) in ecologically vulnerable regions of South Asia: two in the Himalayas (watershed development programme in Lingmutechhu, Bhuthan and Thalisain tehsil, Paudi Grahwal District, Uttarakhand), three in semi-arid parts of western India (watershed development in Hivre Bazar, Maharashtra and Nathugadh village, Gujarat and water-harvesting structures in Gopalapura, Rajasthan) and one in the flood-plains of the Brahmaputra–Jamuna (Char land, Galibanda and Jamalpur districts, Bangladesh). Watersheds in semi-arid regions fall in the low-rainfall region (500–700 mm) and suffer the vagaries of drought 2–3 years in every five-year cycle. In all these locations, the major occupation is agriculture, most of which is rainfed or dry. The other two cases (in Uttarakhand) fall in the Himalayan region (temperate/sub-temperate climate), which has witnessed extensive deforestation in the last century and is now considered as one of the most vulnerable locations in South Asia. Terraced agriculture is being practised in these locations for a long time. The last case (Gono Chetona) falls in the Brahmaputra–Jamuna charlands which are the most ecologically vulnerable regions in the sub-continent with constantly changing landscape. Agriculture and livestock rearing are the main occupations, and there is substantial seasonal emigration for wage labour by the adult males. River erosion and floods force the people to adopt a semi-migratory lifestyle. The book attempts to analyse the potential as well as limitations of NGOdriven CBNRM endeavours across agroclimatic regions of South Asia with emphasis on four intrinsically linked normative concerns, namely sustainability, livelihood enhancement, equity and demographic decentralization in chapters 2–7. Comparative analysis of these case studies done in chapter 8, highlights the issues that require further research while portraying the strengths and limits of NGO-driven CBNRM. In Hivre Bazar, the post-watershed intervention scenario is such that farmers often grow three crops in a year – kharif bajra, rabi jowar and summer vegetable crops. Productivity has increased in the dry lands due to improvement in soil moisture levels. The revival of johads in Gopalpura has led to the proliferation of wheat and increased productivity. In Lingmuteychhu, productivity gains have also arisen, but more due to the introduction of both local and high-yielding, new varieties as opposed to increased water availability. In the case of Gono Chetona, improvements have come due to diversification of agriculture; for example, the promotion of vegetable gardens. CBNRM interventions in most cases have also led to new avenues of employment and income generation. The synthesis shows that CBNRM efforts have made significant contributions to livelihood enhancement and only limited gains in terms of collective action for sustainable and equitable access to benefits and continuing resource use, and in terms of democratic decentralization, contrary to the objectives of the programme. Livelihood benefits include improvements in availability of livelihood support resources (fuelwood, fodder, drinking water), increased productivity (including diversification of cropping pattern) in agriculture and allied activities, and new sources of livelihood. However, NGO-driven CBNRM has not met its goal of providing ‘alternative’ forms of ‘development’ due to impediments of state policy, short-sighted vision of implementers and confrontation with the socio-ecological reality of the region, which almost always are that of fragmented communities (or communities in flux) with unequal dependence and access to land and other natural resources along with great gender imbalances. Appalling, however, is the general absence of recognition of the importance of and the will to explore practical ways to bring about equitable resource transfer or benefit-sharing and the consequent innovations in this respect that are evident in the pioneering community initiatives such as pani panchayat, etc. Pertaining to the gains on the ecological sustainability front, Hivre Bazar and Thalisain initiatives through active participation of villagers have made significant regeneration of the water table within the village, and mechanisms such as ban on number of bore wells, the regulation of cropping pattern, restrictions on felling of trees and free grazing to ensure that in the future, the groundwater is neither over-exploited nor its recharge capability impaired. Nevertheless, the longterm sustainability of the interventions in the case of Ghoga and Gopalpura initiatives as the focus has been mostly on regeneration of resources, and less on regulating the use of regenerated resources. Further, in Lingmuteychhu and Gono Chetona, the interventions are mainly household-based and the focus has been less explicit on ecological components. The studies demonstrate the livelihood benefits to all of the interventions and significant variation in achievements with reference to sustainability, equity and democratic decentralization depending on the level and extent of community participation apart from the vision of implementers, strategy (or nature of intervention shaped by the question of community formation), the centrality of community formation and also the State policy. Case studies show that the influence of State policy is multi-faceted and often contradictory in nature. This necessitates NGOs to engage with the State in a much more purposeful way than in an ‘autonomous space’. Thus the role of NGOs in CBNRM is complementary, wherein they provide innovative experiments that the State can learn. This helps in achieving the goals of CBNRM through democratic decentralization. The book addresses the vital issues related to natural resource management and interests of the community. Key topics discussed throughout the book are still at the centre of the current debate. This compilation consists of well-written chapters based on rigorous synthesis of CBNRM case studies, which will serve as good references for students, researchers and practitioners in the years to come.

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A new species of lygosomatine scincid lizard is described from the sacred forests of Mawphlang, in Meghalaya, northeastern India. Sphenomorphus apalpebratus sp. nov. possesses a spectacle or brille, an unusual feature within the Scincidae, and a first for the paraphyletic genus Sphenomorphus. The new species is compared with other members of the genus to which it is here assigned, as well as to members of the lygosomatine genera Lipinia and Scincella from mainland India, the Andaman and Nicobar Islands, and south-east Asia, to which it also bears resemblance. The new taxon is diagnosable in exhibiting the following combination of characters: small body size (SVL to 42.0 mm); moveable eyelids absent; auricular opening scaleless, situated in a shallow depression; dorsal scales show a line of demarcation along posterior edge of ventral pes; midbody scale rows 27-28; longitudinal scale rows between parietals and base of tail 62-64; lamellae under toe IV 8-9; supraoculars five; supralabials 5-6; infralabials 4-5; subcaudals 92; and dorsum golden brown, except at dorsal margin of lateral line, which is lighter, with four faintly spotted lines, two along each side of vertebral row of scales, that extend to tail base. The new species differs from its congeners in the lack of moveable eyelids, a character shared with several distantly related scincid genera.

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We carried out a large-scale phylogenetic analysis of fejervaryan (dicroglossid frogs with `Fejervaryan lines' on the ventral side of the body) frogs, distributed in South and SE Asia, using published and newly generated sequences of unidentified individuals from the northern Western Ghats. The results corroborate the presence of a larger fejervaryan clade with a sister relationship to a clade composed of Sphaerotheca. Two sister clades could be discerned within the lager fejervaryan clade. The unidentified individuals formed a monophyletic group and showed a strong support for a sister relationship with Minervarya sahyadris. The species was found to be highly divergent (16S rRNA-4% and tyr-1%) from its sister lineage Minervarya sahyadris, and the clade composed of these two lineages were found to be deeply nested within the larger clade of Fejervarya. Based on this, the genus Minervarya Dubois, Ohler and Biju, 2001 is synonymized under the genus Fejervarya Bolkay, 1915. The unidentified lineage is recognized, based on phylogenetic position, genetic divergence and morphological divergence, as a distinct species and named here as Fejervarya gomantaki sp. nov. The presence of rictal glands was observed to be a synapomorphic character shared by the nested clade members, Fejervarya sahyadris and Fejervarya gomantaki sp. nov. Based on the presence of rictal gland and small size, Minervarya chilapata, a species from a lowland region in the Eastern Himalayas, is synonymized under Fejervarya and evidence for morphological separation from the new species, Fejervarya gomantaki sp. nov. is provided. For the fejervaryan frogs, currently three generic names (Frost, 2015) are available for the two phylogenetic subclades; the genus Fejervarya Bolkay, 1915 for the species of fejervaryan frogs having distribution in the South East Asia; the genus Zakerana Howlader, 2011 for the species of fejervaryan frogs having distribution in the South Asia and the genus Minervarya Dubois, Ohler and Biju, 2001 nested within the `Zakerana clade'. In the phylogenetic analysis Minervarya sahyadris, the new species described herein as Fejervarya gomantaki sp. nov. are nested within the `Zakerana clade', if the `Zakerana clade' for the fejervaryan frogs having distribution in the South Asia is provided a generic status the nomen `Minervarya' should be considered as per the principle of priority of the ICZN Code. Taking into consideration the overlapping distribution ranges of members of the sister clades within the larger fejervaryan clade and the absence of distinct morphological characteristics, we also synonymize the genus Zakerana Howlader, 2011, a name assigned to one of the sister clades with members predominantly distributed in South Asia, under the genus Fejervarya Bolkay, 1915. We discuss the need for additional sampling to identify additional taxa and determine the geographical ranges of the members of the sister clades within Fejervarya to resolve taxonomy within this group.

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Aim of the study: Chloranthus erectus (Buch.-Ham.) Verdcourt (Chloranthaceae) is a shrub native to tropical and temperate zone of Eastern Himalaya of India and South-East Asia and have traditionally been used as a folklore medicine to treat localised swelling, joint pain, skin inflammation, fever and bodyache. In this study, an attempthas been made to demonstrate the anti-inflammatory activity of methanol extract obtained from Chloranthus erectus leaves (MECEL) in acute, sub-acute and chronic mouse models. Materials and methods: Inflammation in the hind paw of Wistar albino rat was induced by carrageenan, histamine and serotonin, and tissue granuloma pouch was induced by cotton pellet method. Antiinflammatory drug-phenylbutazone was used as standard drug for comparison. Results: In acute carrageenan-induced rat hind paw edema, oral administration of MECEL at 200 mg/kg produced significant inhibition of edema by 38.34 % (p<0.01) while the histamine- and serotonin-induced sub-acute model, the inhibition of paw edema reached 52.54 % (p < 0.001) and 25.5 % (p < 0.01), respectively. in a 7-day study, MECEL at 20 and 50 mg/kg produced significant suppression of cotton pellet-induced tissue granuloma formation in rats. Conclusions: This preliminary study revealed that the methanol extract of Chloranthus erectus exhibited significant anti-inflammatory activity in the tested models, and may provide the scientific rationale for its popular folk medicine as anti-inflammatory agent.

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The impact of heating by black carbon aerosols on Indian summer monsoon has remained inconclusive. Some investigators have predicted that black carbon aerosols reduce monsoon rainfall while others have argued that it will increase monsoon rainfall. These conclusions have been based on local influence of aerosols on the radiative fluxes. The impact of aerosol-like heating in one region on the rainfall in a remote region has not been examined in detail. Here, using an atmospheric general circulation model, it has been shown that remote influence of aerosol-like heating can be as important as local influence on Indian summer monsoon. Precipitation in northern Arabian Sea and north-west Indian region increased by 16% in June to July when aerosol-like heating were present globally. The corresponding increase in precipitation due to presence of aerosol-like heating only over South Asia (local impact) and East Asia (remote impact) were 28 and 13%, respectively. This enhancement in precipitation was due to destabilization of the atmosphere in pre-monsoon season that affected subsequent convection. Moreover, pre-monsoon heating of the lower troposphere changed the circulation substantially that enabled influx of more moisture over certain regions and reduced the moist static stability of the atmosphere. It has been shown that regional aerosol heating can have large impact on the phase of upper tropospheric Rossby wave in pre-monsoon season, which acts as a primary mechanism behind teleconnection and leads to the change in precipitation during monsoon season. These results demonstrate that changes in aerosol in one region can influence the precipitation in a remote region through changes in circulation.

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In this paper, using idealized climate model simulations, we investigate the biogeophysical effects of large-scale deforestation on monsoon regions. We find that the remote forcing from large-scale deforestation in the northern middle and high latitudes shifts the Intertropical Convergence Zone southward. This results in a significant decrease in precipitation in the Northern Hemisphere monsoon regions (East Asia, North America, North Africa, and South Asia) and moderate precipitation increases in the Southern Hemisphere monsoon regions (South Africa, South America, and Australia). The magnitude of the monsoonal precipitation changes depends on the location of deforestation, with remote effects showing a larger influence than local effects. The South Asian Monsoon region is affected the most, with 18% decline in precipitation over India. Our results indicate that any comprehensive assessment of afforestation/reforestation as climate change mitigation strategies should carefully evaluate the remote effects on monsoonal precipitation alongside the large local impacts on temperatures.

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Bioshields or coastal vegetation structures are currently amongst the most important coastal habitat modification activities in south-east Asia, particularly after the December 2004 tsunami. Coastal plantations have been promoted at a large scale as protection against severe natural disasters despite considerable debate over their efficacy as protection measures. In this paper, we provide an interdisciplinary framework for evaluating and monitoring coastal plantations. We then use this framework in a case study in peninsular India. We conducted a socio-ecological questionnaire-based survey on government and non-government organizations directly involved in coastal plantation efforts in three 2004 Indian Ocean tsunami affected states in mainland India. We found that though coastal protection was stated to be the primary cause, socio-economic factors like providing rural employment were strong drivers of plantation activities. Local communities were engaged primarily as daily wage labour for plantation. rather than in the planning or monitoring phases. Application of ecological criteria has been undermined during the establishment and maintenance of plantations and there was a general lack of awareness about conservation laws relating to coastal forests. While ample flow of international aid has fuelled the plantation of exotics in the study area particularly after the Indian Ocean tsunami in 2004, the long term ecological consequences need further evaluation and rigorous monitoring in the future. (C) 2014 Elsevier Masson SAS. All rights reserved.

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Human provisioning of wildlife with food is a widespread global practice that occurs in multiple socio-cultural circumstances. Provisioning may indirectly alter ecosystem functioning through changes in the eco-ethology of animals, but few studies have quantified this aspect. Provisioning of primates by humans is known to impact their activity budgets, diets and ranging patterns. Primates are also keystone species in tropical forests through their role as seed dispersers; yet there is no information on how provisioning might affect primate ecological functions. The rhesus macaque is a major human-commensal species but is also an important seed disperser in the wild. In this study, we investigated the potential impacts of provisioning on the role of rhesus macaques as seed dispersers in the Buxa Tiger Reserve, India. We studied a troop of macaques which were provisioned for a part of the year and were dependent on natural resources for the rest. We observed feeding behaviour, seed handling techniques and ranging patterns of the macaques and monitored availability of wild fruits. Irrespective of fruit availability, frugivory and seed dispersal activities decreased when the macaques were provisioned. Provisioned macaques also had shortened daily ranges implying shorter dispersal distances. Finally, during provisioning periods, seeds were deposited on tarmac roads that were unconducive for germination. Provisioning promotes human-primate conflict, as commensal primates are often involved in aggressive encounters with humans over resources, leading to negative consequences for both parties involved. Preventing or curbing provisioning is not an easy task as feeding wild animals is a socio-cultural tradition across much of South and South-East Asia, including India. We recommend the initiation of literacy programmes that educate lay citizens about the ill-effects of provisioning and strongly caution them against the practice.

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Evaluation and design of shore protection works in the case of tsunamis assumes considerable importance in view of the impact it had in the recent tsunami of 26th December 2004 in India and other countries in Asia. The fact that there are no proper guidelines have made in the matters worse and resulted in the magnitude of damage that occurred. Survey of the damages indicated that the scour as a result of high velocities is one of the prime reasons for damages in the case of simple structures. It is revealed that sea walls in some cases have been helpful to minimize the damages. The objective of this paper is to suggest that design of shore line protection systems using expected wave heights that get generated and use of flexible systems such as geocells is likely to give a better protection. The protection systems can be designed to withstand the wave forces that corresponding to different probabilities of incidence. A design approach of geocells protection system is suggested and illustrated with reference to the data of wave heights in the east coast of India.