12 resultados para Reserve Bank of India

em Chinese Academy of Sciences Institutional Repositories Grid Portal


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A double parasitism (isopod Cymothoidae and copepod Pennellidae) on black-barred halfbeak fish, Hemiramphus far, was recorded from Pazhayar coastal waters (southeast coast of India) during September 2008. This is the first report from this region and the infection is discussed in relation to environmental and biological parameters.

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To resolve the phylogeny of the autochthonous mitochondrial DNA (mtDNA) haplogroups of India and determine the relationship between the Indian and western Eurasian mtDNA pools more precisely, a diverse subset of 75 macrohaplogroup N lineages was chosen fo

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This paper reports the occurrence of a marine brachyuran crab species Eucrate alcocki SerSne, in SerSne et al., 1973, of the family Euryplacidae Stimpson, 1871, for first time from India, based on a male specimen from Parangipettai fish landing centre in Bay of Bengal, Southeast Coast of India. Although morphologically corresponding with what is currently defined as E. alcocki, the color pattern of the carapace of the present specimen is rather different from that of the Chinese material-only the anterior fifth of the carapace is marked with scattered red spots, the rest of the surface is yellowish, with four unusually shaped red blotches which almost look like Sanskrit characters.

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In order to study the differentiation of Asian colobines, 14 variables measured on 123 skulls, including Rhinopithecus, Presbytis, Presbytiscus (Rhinopithecus avunculus), Pygathrix and Nasalis were analyzed by one-way, cluster and discriminant function analyses. Information on paleoenvironmental changes in China and southeast Asia since the late Tertiary was used to examine the influences of migratory routes and range of distribution in Asian colobines. A cladogram for 6 genera of Asian colobines was constructed from the results of various analyses. Some new points or revisions were suggested: (1) Following one of two migratory routes, ancient species of Asian colobines perhaps passed through Xizang (Tibet) along the northern bank of the Tethys sea and through the Heng Duan Shan regions of Yunnan into Vietnam. An ancient landmass linking Yunnan and Xizang was already present on the east bank of the Tethys sea. Accordingly, Asian colobines would have two centers of evolutionary origin: Sundaland and the Heng Duan Shan regions of China. (2) Pygathrix shares more cranial features with Presbytiscus than with Rhinopithecus. This differs somewhat from the conclusion reached by Groves. (3) Nasalis (karyotype: 2n = 48) may be the most primitive genus among Asian colobines. Certain features shared with Rhinopithecus, e.g. large body size, terrestrial activity and limb proportions, can be interpreted as symple-siomorphic characters. (4) Rhinopithecus, with respect to craniofacial features, is a special case among Asian colobines. It combines a high degree of evolutionary specialization with retention of some primitive features thought to have been present in the ancestral Asian colobine.

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Onychostoma virgulatum, new species, is described from the Qiupu River, a tributary on the Southern bank of the lower Yangtze River at Shitai County, southern Anhui Province, South China. It shares with O. fusiforme and O. meridionale the presence of a longitudinal dark brown stripe extending along the lateral line, a character separating them from all other congeners of the moderate-mouth group diagnosed by having a slightly arched or nearly transverse mouth opening (with the extremities slightly curved posteriorly), its width being equal to or slightly less than the width of head at this same point, and a short postlabial groove extending along half of the length of the lateral margin of the lower jaw. Onychostoma virgulatum differs from both in the presence of two pairs of barbels in adults, from O. fusiforme in the body depth, caudal-peduncle depth, and position of pelvic and anal fins, and from O. meridionale in the structure of the last simple dorsal-fin ray.

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The Yangtze finless porpoise (Neophocaena phocaenoides asiaeorientalis) is currently limited to the middle and lower reaches of the Yangtze River from Yichang to Shanghai, China, and the adjoining Poyang and Dongting Lakes. Its population size has decreased remarkably during the last several decades due to the heavy impact of human activities, including overfishing of prey species, water development projects that cause attendant habitat loss and degradation, water pollution, and accidental deaths caused by harmful fishing gear and collisions with motorized vessels. It was estimated that the number of remaining individuals was down to approximately 1800 in 2006, a number that is decreasing at a rate as high as 5% per year. Three conservation measures - in situ and ex situ conservation and captive breeding have been applied to the protection of this unique porpoise since the early 1990s. Seven natural and two "semi-natural" reserves have so far been established. Since 1996, a small group of finless porpoises has been successfully reared in a facility at the Institute of Hydrobiology of the Chinese Academy of Sciences; three babies were born in captivity on July 5, 2005, June 2, 2007 and July 5, 2008. These are the first freshwater cetaceans ever born in captivity in the world. Several groups of these porpoises caught in the main stream of the Yangtze River, or rescued, have been introduced into the Tian'e-Zhou Semi-natural Reserve since 1990. These efforts have proven that, not only can these animals survive in the area, they are also to reproduce naturally and successfully. More than 30 calves had been born in the reserve since then, with one to three born each year. Taking deaths and transfers into account, there were approximately 30 individuals living in the reserve as of the end of 2007. Among eight mature females captured in April 2008, five were confirmed pregnant. This effort represents the first successful attempt at off-site protection of a cetacean species in the world, and establishes a solid base for conservation of the Yangtze finless porpoise. A lesson must be drawn from the tragedy of Chinese River Dolphin (Lipotes vexillifer), which has already been declared likely extinct. Strong, effective and appropriate protective measures must be carried out quickly to prevent the Yangtze finless porpoise from becoming a second Chinese River Dolphin, and save the biodiversity of the Yangtze River as a whole.

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岷江上游地区高山/亚高山植被分布的坡向性分异显著,阴阳坡高山林线不仅物种组成差异明显,并且分布海拔呈现出阴坡高阳坡低的格局.阳坡林线树种主要是圆柏属乔木,林线类型多为渐变型,海拔高度大约在3 400m~3 800m;阴坡林线树种主要是冷杉,林线类型多为骤变型,海拔高度约在3 800m~4 400m.本研究采用土壤种子库物理筛选、室内萌发实验及野外群落调查等方法,对岷江上游地区阴坡岷江冷杉和阳坡祁连圆柏两类林线树种不同海拔梯度上土壤种子库以及幼苗库特征进行了调查,从土壤种子库和幼苗更新特征的角度对林线乔木树种种群更新特征进行了分析,进而对该地区高山林线在阴阳坡分布差异的原因进行了探讨,结果显示: 1.土壤种子库 阴坡:阴坡高山林线附近岷江冷杉土壤种子的平均密度大约为50.96粒/m2,其中树线以上10m处土壤种子密度为1.00粒/m2,树线处大约19.33粒/m2,林线交错带内土壤种子密度最高为136.83粒/m2,郁闭林内种子密度小于林线交错带,只有30.50粒/m2,种子平均空壳率为52%,霉变率达34%,完好种子只有6%.土壤种子库垂直分布特征为地被物层含种子比重最大,大约在67.50%左右;其次为0~2cm层,约18.84%左右;2~5cm层所占种子比例最小,约13.66%左右.霉变种子数量与土壤深度呈负相关. 阳坡:阳坡祁连圆柏土壤种子的平均密度为60.16粒/m2.树线以上10m处密度为1.92粒/m2,树线位置大约108.16粒/m2,林线交错带内平均为75.80粒/m2,郁闭林内种子密度小于林线交错带,只有20.00粒/m2.种子平均空壳率为36%,完好种子占49%,霉变率较低,大约为10%.阴阳坡林线树种土壤种子库垂直分布特征为:地被物层含种子最多,其次为0~4cm层,4~10cm层所占种子比例最小,霉变种子数量与土壤深度也呈负相关. 2. 幼苗库调查 阳坡:在树线以上区域没有发现幼苗,林线交错带内幼苗密度平均达3 250株/hm2,郁闭林内仅2 750株/ hm2.整个样地内1~2a幼苗很少甚至没有出现,3~10a的幼苗相对较多.空间分布上,祁连圆柏幼苗在林线交错带内接近随机分布,郁闭林内则介于随机分布和均匀分布之间. 阴坡:在树线以上幼苗密度为1 250株/ hm2,全部为1~2a幼苗,林线交错带内幼苗密度平均达7 000株/ hm2,郁闭林内达6 250株/ hm2.林线附近岷江冷杉幼苗丰富度以及幼苗的出现频率明显高于祁连圆柏,年龄结构也较祁连圆柏完整.岷江冷杉幼苗空间分布除了树线处幼苗的分布为随机分布,其他海拔则为集群分布. 3.从不同土壤深度的种子总量和幼苗数量的相关性检验发现,当年生幼苗数量跟表层种子总量相关性极显著, 但是两年生幼苗的数量与底层种子数量相关性显著.土壤种子在土壤中的垂直分布格局从一定程度上可以反映种子库的年际特征.岷江冷杉土壤种子库较丰富,种子散布后的存活力随着时间的变化逐渐下降,属于季节性瞬时种子库;祁连圆柏土壤种子散布格局为集群型分布,成熟种子大部分散布在母株冠幅内,属于永久性土壤种子库. 4.在阴坡林线交错带及以上区域还存在较为丰富的乔木土壤种子,并且在树线以上区域还发现了少量的岷江冷杉幼苗.从样地乔木的年龄结构发现,在林线交错带内上部到树线位置主要以幼龄林为主,且年龄结构完整,基本符合入侵性林线特征;阳坡林线交错带内幼苗出现频率很低,树线以上区域虽然存在种子库,但是没有幼苗出现,在林线交错带内乔木径级差距很大,年龄结构异常不完整,这种特征的林线将会面临两个可能结果:一种是维持现有状态,保持平衡;另外一种就是退化,但阳坡林线的实际动态趋势还有待长期定点研究. Treelines on the upper region of Minjiang River differ between the north aspect and the south aspect in their appearances, altitudes and tree species. On the north aspect, trees of Abies form a sharp and abrupt treeline ranging from 3800m to 4400m, while on the south the treeline is generally lower(3 400~3 800m), more open and gradual and mostly composed of Sabina. In this study, we examined the altitudinal gradients of soil seed banks and seedling recruitments at the treeline ecotones of a N-aspect and a S-aspect by using soil sieving, germination experiment and field investigations, analyzed the characteristics of population regeneration of tree species at the transitional zone and presented a analysis of the causes to the aspect-related difference in treeline patterns in the study area. Major results of our study include: 1. Soil seed bank N-aspect: Of the 50 plots investigated, the average density of soil seeds is 50.96/m2, in which well-formed seeds account for 6%, empty seeds 52%, parasitized seeds34%, and seeds damaged by animals 8%. The size of soil seed bank varies along altitude, being 1.00 seeds /m2 at the 10m above the treeline and ca.19.33 seeds/m2 at the upper limit of treeline. The highest density (136.83 seeds/m2) occurs at the treeline ecotone. By contrast, the density of soil seed for the closed forest is only 30.50 seeds/m2. In terms of vertical strata, 67.50% of the total seeds are at the surface layer, 18.84% at the middle layer (0~2cm) and 13.66% at deeper layer (2~5cm). The number of parasitized seeds is negatively correlated to soil depth. S-aspect: Of the 50 plots investigated, the average density of soil seeds is 60.16 seeds/m2, and the well-formed seeds account for 49%, empty seeds 36%, parasitized seeds10%, and seeds damaged by animals 1%. The size of soil seed bank varies along altitude, with 1.92 seeds/m2 recorded at the10m above the treeline,108.16 seeds/m2 at the upper limit of treeline, and 75.80 seeds/m2 at the treeline ecotone, while that for the closed forest is 20.00 seeds/m2. The number of seeds decreases with the depth of soil. As is on the N-aspect, the size of soil bank, from large to small, follows the order of the surface layer, the middle layer (0~4cm) and the bottom layer (4~10cm). The number of parasitized seeds is also negatively correlated to the depth of the soil. 2. Seedling bank N-aspect: A mean maximum seedling abundance of 31 000 seedlings/hm2 was recorded near alpine treeline at growing season. The density of seedlings is 1 250 seedlings/ha (all being 1 or 2 years old) at the alpine meadow 10m away above treeline, 7 000 seedlings/ha at treeline ecotone and 6 250 seedlings/ha for closed forest.The spatial distribution of Abies faxoniana seedlings is random at the upper limit of the treeline but clumped at other altitudes. S-aspect: No seedlings were found at the alpine meadow 10m away from the treeline. The density of seedlings was 3 250 seedlings/ha at treeline ecotone and 2 750 seedlings/ha for the closed forest.Hardly any 1 year current and 2 year-old seedlings appeared at the plots. The spatial distribution of Sabina przewalskii seedlings is random at treeline ecotone and between “random” and “even” forest closed forest. 3.Correlation tests of seedling population and seed bank at different soil layers indicated that the emergents were strongly correlated to seed bank at surface layer while the number of two-year seedlings was significantly correlated to the seed bank at the bottom of soil layer, indicating that germination mainly occurs at the soil surface while the middle or bottom layer was the reserve for non-germination or dead seeds. It can thus be postulated that Abies faxoniana soil seed bank is of seasonal transient type. By contrast, the soil seed bank of Sabina przewalskii is of persistent type and the soil seeds and seedlings of this species occurred more frequently near the islands of adult trees. 4.A good many soil seeds of both tree species were found near the treeline ecotone and above at N- and S-aspects. A few young seedlings were found above the Abies treeline. Investigation of five altitudinal transects respectively on N- and S-aspects indicated that Abies faxoniana has a more complete age structure than the stands of Sabina przewalskii. The age of firs decreased from closed forest to the upper limit of treeline, which suggests that the Abies treeline is advancing to higher altitude. While on the south aspect, only few Sabina przewalskii soil seeds and nearly no seedlings were found above the treeline ecotone. The stands exhibit extremely great difference in diameter classes with significantly incomplete age structure. This would lead to two possible results for the treelines: maintaining an equilibrium state at the current position or degenerating. But more studies should be carried out at longer time scales or larger spatial scales to understand whether the Sabina treeline is degenerating.

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Geochemical processes in estuarine and coastal waters often occur on temporally and spatially small scales, resulting in variability of metal speciation and dissolved concentrations. Thus, surveys, which are aimed to improve our understanding of metal behaviour in such systems, benefit from high-resolution, interactive sampling campaigns. The present paper discusses a high-resolution approach to coastal monitoring, with the application of an automated voltammetric metal analyser for on-line measurements of dissolved trace metals in the Gulf of Cadiz, south-west Spain. This coastal sea receives metal-rich inputs from a metalliferous mining area, mainly via the Huelva estuary. On-line measurements of dissolved Cu, Zn, Ni and Co were carried out on-board ship during an eight-day sampling campaign in the study area in June 1997. A pumping system operated continuously underway and provided sampled water from a depth of ca. 4 m. Total dissolved metal concentrations measured on-line in the Gulf of Cadiz ranged between <5 nM Cu (<3 nM Ni) ca. 50 km off-shore and 60–90 nM Cu (5–13 nM Ni) in the vicinity of the Huelva estuary. The survey revealed steep gradients and strong tidal variability in the dissolved metal plume extending from the Huelva estuary into the Gulf of Cadiz. Further on-line measurements were carried out with the automatic metal monitor from the bank of the Odiel estuary over a full tidal cycle, at dissolved metal concentrations in the μM range. The application confirmed the suitability of the automated metal monitor for coastal sampling, and demonstrated its adaptability to a wide range of environmental conditions in the dynamic waters of estuaries and coastal seas. The near-real time acquisition of dissolved metal concentrations at high resolution enabled an interactive sampling campaign and therefore the close investigation of tidal variability in the development of the Huelva estuary metal plume.

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[1] The evolution of freshwater plumes and the associated salinity fronts in the northern Bay of Bengal ( henceforth the bay) is studied using rotated empirical orthogonal function (REOF) analysis and extended associate pattern analysis (EAPA). The results show that sea surface salinity distribution is featured by eastern-bay and western-bay plumes in the northern bay during different seasons. The western-bay plume begins in early July, peaks in late August, and then turns into a bay-shaped plume with the two plumes in either side of the bay, which peaks in late October. The southward extension of the western-bay plume can be explained by the southwestward geostrophic flow associated with the cyclonic gyre in the northern bay, which counters the northeastward Ekman drift driven by wind stress. The offshore expansion of the western-bay plume is induced by the offshore Ekman drift which also produces a salinity front near the east coast of India. The bay-shaped plume appears when the cyclonic gyre shifts westward and a weak anticyclonic gyre occupies the northeastern bay. As the season advances, the western part of the bay-shaped plume decays while the eastern part persists until the following June, which is believed to be associated with the anticyclonic gyre in the northern bay. The evolution of the plumes except the eastern part of the bay-shaped plume in fall can be partly explained by the seasonal variation of mass transport associated with the Sverdrup balance. The fact that the western-bay (eastern-bay) plume appears when surface freshwater flux in the northeastern bay increases ( decreases) dramatically suggests that the plumes are not produced directly by surface freshwater flux. River discharge seems to be the freshwater source for the plumes and has little to do with the evolution of the plumes.