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131.
为了解热带印度洋的水声场,利用2004-2013年10a的地转海洋学实时观测阵(Argo)资料,根据声速计算经验公式,对水声的水平分布、铅直断面分布、声跃层的分布、季节变化和铅直结构进行了较为全面的分析,并对强跃层区进行逐月研究。结果表明,50m深度层声速场呈北高南低的纬向带状分布形式,而200m深度层声速场由北向南呈现高—低—高—低分布;在85°E断面上,声速等值线在赤道以南存在较大的槽、脊,而在赤道以北较为平直;声跃层的深度冬季总体分布为南浅北深,夏季在10°N西印度洋和10°S东印度洋各有一部分明显的较深区域;跃层厚度普遍冬季大于夏季,东部大于西部,跃层强度的分布在冬季存在1个高值区,在夏季存在2个高值区;跃层的断面分布上,其结构、强度和位置都随季节有明显变化。  相似文献   
132.
Interdecadal variability in the tropical Indian Ocean has been analyzed based on the long-term climatic observational data. Case study showed that strong interannual signals formed at the surface can penetrate the depth of seasonal thermocline, where the anomalies last a couple of years. Artificial time series based on damping with exponential decay of selected strong events agree well with the detected interdecadal variability in the tropical Indian Ocean. A possible dynamic explanation for interdecadal variability in the tropical Indian Ocean was proposed that irregular interannual signals can lead to a slowly evolving climatic background with the interdecadal time scale through damping of the memory about anomalies in the seasonal thermocline.  相似文献   
133.
论印度种姓制度对西藏社会所带来的负面影响   总被引:1,自引:0,他引:1  
人类已步入高度文明的二十一世纪,但无形的种姓意识至今仍然困扰着青藏高原上赖以生存的许多人,即便受过高等教育的现代人也很难摆脱这种困境,于是出现了干涉婚姻、家庭不和、邻里不和睦、离家出走及亲朋断绝来往等许多社会问题,也势必直接或间接地影响社会主义和谐西藏的建设。然而西藏和谐社会建设是我国和谐社会建设的重要组成部分,应逐渐淡化消除存在这种不利因素的根源。文章对印度种姓制度的起源、发展、比较及其传播到西藏的途径、负面影响、现状进行剖析,提出了如何预防这种不利于建设和谐社会的种姓意识的对策,并强调了提高自身修养,保持高贵品德的重要性。  相似文献   
134.
Rapid socio-economic changes in some developing countries, including India, are creating new scopes for application of precision agriculture (PA). The implications of dramatic shifts for economic development, urbanization and energy consumption in some developing countries are immense. High-tech nature of traditional PA technologies developed in advanced countries created a real challenge for engineers to search suitable PA technologies for developing countries. It is expected that application of balanced soft and hard PA technologies based on the need of specific socio-economic condition of a country will make PA suitable for developing countries also.‘Soft’ PA depends mainly on visual observation of crop and soil and management decision based on experience and intuition, rather than on statistical and scientific analysis. ‘Hard’ PA utilizes all modern technologies such as GPS, RS, and VRT. Three components, namely,‘single PA technology’, ‘PA technology package’ (for the user to select one or combination) and ‘integrated PA technology’, have been identified as a part of adoption strategies of PA in the developing countries. Therefore, the objective of this paper is to find out the scope,the present status and the strategies for adoption of PA in India and in some developing countries. Application of PA in cash crop, plantation crop, etc. has been discussed. Application of some medium and low-tech PA tools such as chlorophyll meter and leaf colour chart in small farms has been included. This exhaustive review of the present status of PA in India and in some developing countries is expected to help to find out the adoption trend and direction of future research. Detailed strategy for the adoption of PA in India has also been proposed.  相似文献   
135.
Diatoms are one of the predominant contributors to global carbon fixation by accounting for over 40% of total oceanic primary production and dominate export production. They play a significant role in marine biogeochemistry cycle. The diatom mat deposits are results of vast diatoms bloom. By analysis of diatom mats in 136°00′--140°00′E, 15°00′--21°00′N, Eastern Philippines Sea, we identified the species of the diatoms as giant Ethmodiscus rex (Wallich) Hendey. AMS 14C dating shows that the sediments rich in diatom mats occurred during 16000--28600 a B.P., which means the bloom mainly occurred during the last glacial period, while there are no diatom mat deposits in other layers. Preliminary analysis indicates that Antarctic Intermediate Water (AAIW) expanded northward and brought silicate-rich water into the area, namely, silicon leakage processes caused the bloom of diatoms. In addition, the increase of iron input is one of the main reasons for the diatom bloom.  相似文献   
136.
Yao  TanDong  Zhou  Hang  Yang  XiaoXin 《科学通报(英文版)》2009,54(16):2724-2731
The δ^18O variation in precipitation acquired from 28 stations within the network of Tibetan Observation and Research Platform (TORP) is studied, with the focus on the altitude effect of δ^18O in river water during monsoon precipitation in an effort to understand the monsoon influence on isotopic composition in annual river water. It is found that δ^18O in precipitation on the Plateau is influenced by different moisture sources, with significant Indian monsoon influence on δ^18O composition in plateau precipitation and river water. The δ^18O of water bodies in the monsoon domain is generally more depleted than that in the westerly domain, suggesting gradual rainout of southwesterly borne marine moisture in the course of long-distance transportation and lifting over the Himalayas. The lapse rate of δ^18O in river water with altitude is the largest during monsoon precipitation, due to the increased temperature vertical gradient over the southern Plateau region controlled by monsoon circulation. The combination of δ^18O in river water in monsoon (wet) and non-monsoon (dry) seasons shows a larger lapse rate than that in non-monsoon (dry) season alone. As the altitude effect of δ^18O in precipitation and river water on the Tibetan Plateau results from the combined effect of monsoon moisture supply and westerly moisture supply, the δ^18O composition and its altitude effect on the Plateau during monsoon seasons should be considered in the reconstruction of paleoelevation of the Tibetan Plateau.  相似文献   
137.
采用POM模式对2005年西北太平洋西边界流系源区进行了数值模拟.针对该海区海表热通量与POM模式匹配困难的问题,在模拟过程中,分别采用由同化AMSR卫星资料插值得到的日平均海表温度场以及由NCEP资料得到的海表净热通量与长、短波辐射通量两种方案来进行海表热强迫.通过与SODA资料的分析结果对比,POM模式模拟结果较好地显示出北赤道流,黑潮源区及棉兰老海流的基本特征,两处断面流速与实际探测资料较为吻合;高度场模拟结果与实况较为一致,但0.9m水位高度线范围呈缩小-放大-缩小-放大的季节性震荡与实况中维持稳定存在一定差异;海温模拟结果与月平均的SODA资料总体一致,但在春夏两季温度略高.  相似文献   
138.
139.
《Journal of Natural History》2012,46(23-24):3143-3173
A total of seven species of Polyplacophora, namely Parachiton hylkiae mauricejayi Schwabe, 2002 Schwabe E 2002 A new subspecies of the genus Parachiton Thiele, 1909 Thiele J 1909 Revision des Systems der Chitonen. I. Teil Zoologica Stuttgart 22, 1–70, pls?1–6  <!--${googleScholarLinkReplacer: %00empty%00 book +Zoologica+Stuttgart+ author%3DJ+Thiele 1909 ++%0AThiele+++J+++++1909++++Revision+des+Systems+der+Chitonen.+I.+Teil++++Zoologica+Stuttgart+++++++22%2C+1%E2%80%9370%2C+pls%E2%80%891%E2%80%936+ %00empty%00 %00null%00}--> from the Indian Ocean Of Sea and Shore 24(4), 220–223  [Google Scholar], Callochiton deshayesi Thiele, 1909 Thiele J 1909 Revision des Systems der Chitonen. I. Teil Zoologica Stuttgart 22, 1–70, pls?1–6  [Google Scholar], Callistochiton barnardi Leloup, 1981, Lucilina indica (Leloup, 1981), Onithochiton maillardi (Deshayes, 1863 Deshayes G. P 1863 Catalogue des mollusques de l'Ile de la Réunion (Bourbon) in L. Maillard (ed.) Notes sur l'Ile de la Réunion (Paris: Dentu), pp.?1–144, pls?28–41  [Google Scholar]), Choneplax indica Odhner, 1919 Odhner N. H. J 1919 Contribution à la faune malacologique de Madagascar Arkiv för Zoologi 12(6), 1–52, pls?1–4  [Google Scholar] and Cryptoconchus oliveri n. sp., were collected during a survey of marine biodiversity at Rodrigues. For all the species taxonomically relevant characters are described, and for the first time are illustrated in detail using SEM photography. The taxonomic status of Lucilina indica (Leloup, 1981) is clarified, and it is rejected from the synonymy of Lucilina carnosa (Kaas, 1979 Kaas P 1979 The chitons (Mollusca: Polyplacophora) of Mozambique Annales of the Natal Museum 23(3), 855–879  [Google Scholar]).  相似文献   
140.
《Journal of Natural History》2012,46(13-14):1065-1077
Over the last two decades, several works on the family Ampeliscidae have been published, in particular about three of the four genera in the family: Ampelisca, Byblis, and Haploops. Recently, additional material collected during the BIOFAR sampling around the Faeroe Islands and during the BIOICE sampling around Iceland, in the Bay of Biscay and the EUMELI 2 campaign along the African coasts were examined. The genus Haploops was numerous (>3500 individuals), and within this material were interesting specimens. Six of them, found at four stations about 100 km off Mauritania, have been recognized as Haploops lodo (Barnard, 1961 Barnard, J. L. 1961. Gammaridean amphipoda from depths of 400 to 6000 m.. Galathea Report, 5: 23128.  [Google Scholar]) a bathyal and abyssal species previously seen only in the Pacific ocean offshore of the American coasts. In this article, an Atlantic H. lodo specimen representative of the Atlantic specimens is compared to the holotype. The geographical and bathymetric distribution of H. lodo in the depths of the North Atlantic and Pacific Oceans are discussed.  相似文献   
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