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1.
The warming of the Earth's atmosphere system is likely to change temperature and precipitation, which may affect the climate, hydrology and water resources at the river basins over the world. The importance of temperature change becomes even greater in snow or glacier dominated basins where it controls the snowmelt processes during the late‐winter, spring and summer months. In this study hydrologic responses of streamflow in the Pyanj and Vaksh River basins to climate change are analysed with a watershed hydrology model, based on the downscaled atmospheric data as input, in order to assess the regional climate change impact for the snowfed and glacierfed river basins in the Republic of Tajikistan. As a result of this analysis, it was found that the annual mean river discharge is increasing in the future at snow and glacier dominated areas due to the air temperature increase and the consequent increase in snow/ice melt rates until about 2060. Then the annual mean flow discharge starts to decrease from about 2080 onward because the small glaciers start to disappear in the glacier areas. It was also found that there is a gradual change in the hydrologic flow regime throughout a year, with the high flows occuring earlier in the hydrologic year, due to the warmer climate in the future. Furthermore, significant increases in annual maximum daily flows, including the 100‐year return period flows, at the Pyanj and Vaksh River basins toward the end of the 21st century can be inferred from flood frequency analysis results. Copyright © 2012 John Wiley & Sons, Ltd.  相似文献   
2.
为了对境外地质矿产勘查开发提供遥感信息支持,在综合前人研究成果及野外验证基础上,对塔吉克斯坦帕米尔地区的地质和构造特征进行深入分析和研究;根据不同地质体的特征影像,对照"资源一号"(ZY-1)02C星遥感图像中所显示的地貌景观、色调及纹形等,建立了塔吉克斯坦南部地区主要沉积岩、变质岩和侵入岩以及断裂构造、褶皱构造和环形构造等的遥感解译标志;通过对ZY-1 02C星的全色/多光谱相机(P/MS)和全色高分辨率相机(HR)数据的遥感地质解译效果对比,认为P/MS数据中地质体的色调差异更为明显,易于建立区域构造格架、开展岩石大类解译;而HR数据所反映地质体的微地貌、纹理及细节更为清晰,易于进一步识别各类岩性及小型构造,尤其对碎屑岩的粒度、层状构造类型、第四系、矿业活动以及特殊成分的岩石等具有较好的反映。  相似文献   
3.
 A lumped-parameter model of groundwater balance is proposed that permits an estimate of discharge variability in comparison with the variability of recharge, by taking into account the influence of aquifer parameters. Recharge–discharge relationships are analysed with the model for cases of deterministic and stochastic recharge time-series variations. The model is applied to study the temporal variability of groundwater discharge in a river valley in the territory of Tajikistan, an independent republic in Central Asia. Received, April 1996 Revised, August 1997 Accepted, March 1998  相似文献   
4.
塔吉克斯坦横跨古亚洲洋、特提斯两大构造域,北部地区属南天山晚海西褶皱系,南部属于阿尔卑斯-喜玛拉雅巨型构造带,其中酸性岩浆岩分布广泛。该国铀矿资源丰富,已成为其重要的优势矿产资源之一。笔者通过系统分析塔吉克斯坦各分区含铀地质建造特征,结合已知铀矿点成矿类型和野外地质工作成果,总结其铀矿分布规律,剖析了3处铀成矿区,圈定2处有利的勘查区域。通过该项目研究,对国内塔里木盆地南缘和西昆仑等地的铀成矿预测可以起借鉴作用,同时对中国铀企业走出去起到指导作用。  相似文献   
5.
塔吉克斯坦帕米尔地区由一系列呈近东西向、向北凸出的弧形活动构造带构成,被称为“西构造结”。由于地缘关系及国内外研究程度差异,塔吉克帕米尔地区在构造单元属性及其与国内构造单元对比上仍存在分歧。本文在系统分析塔吉克帕米尔地区、昆仑和藏北地区区域地质调查和科研成果资料的基础上,结合野外地质调查,着重从物质组成、构造变形两个方面进行对比,以坦尼马斯、如山-帕沙尔特缝合带为界将塔吉克帕米尔地区自北向南划分为北帕米尔、中帕米尔、南帕米尔三个构造单元,其中北帕米尔进一步细化为北带、中带、南带,南帕米尔分为东南帕米尔和西南帕米尔。初步探讨了各单元构造属性,提出了与我国昆仑、藏北地区相邻构造单元的对接方案,为推进帕米尔地区区域地质研究提供支撑。  相似文献   
6.
Climate change due to global warming is a public concern in Central Asia. Because of specific orography and climate conditions, the republic of Tajikistan is considered as the main glacial center of Central Asia. In this study, regional climate change impacts in the two large basins of Tajikistan, Pyanj and Vaksh River basins located in the upstream sector of the Amu Darya River basin are analysed. A statistical regression method with model output statistics corrections using the ground observation data, Willmott archived dataset and GSMaP satellite driven dataset, was developed and applied to the basins to downscale the Global Climate Model Projections at a 0.1‐degree grid and to assess the regional climate change impacts at subbasin scale. It was found that snow and glacier melting are of fundamental importance for the state of the future water resources and flooding at the target basins since the air temperature had a clearly increasing trend toward the future. It was also found that the snowfall will decrease, but the rainfall will increase because of the gradual increase in the air temperature. Such changes may result in an increase in flash floods during the winter and the early spring, and in significant changes in the hydrological regime during a year in the future. Furthermore, the risks of floods in the target basins may be slightly increasing because of the increase in the frequencies and magnitudes of high daily precipitation and the increase in the rapid snowmelt with high air temperatures toward the future. Copyright © 2012 John Wiley & Sons, Ltd.  相似文献   
7.
Smaller foraminifers from Upper Yakhtashian and Bolorian deposits of the stratotype area (Pamir, Darvaz, Tajikistan) are investigated. Four assemblages are defined. The first assemblage is from Chalaroschwagerina vulgaris-Pamirina darvasica Zone. The second assemblage found in the transitional Yakhtashian-Bolorian beds includes Globivalvulina, Palaeotextulariidae, Hemigordiidae, and Glomospira, associated with the first Pachyphloia and Langella forms. Characteristic taxa of third assemblage from the Misellina (Brevaxina) dyhrenfurthi Zone are Geinitzinidae, Globivalvulina, Palaeotextulariidae, Glomospira, and rare Pachyphloia. The forth assemblage of Hemigordiidae, Pachyphloia, Palaeotextulariidae, Geinitzinidae, Pseudoagathammina is identified in the M. (Misellina) parvicostata Zone. The assemblages were compared with concurrent analogs from China, Japan, and Russia. New species and subspecies Glomospira paleograndis sp. nov., G. darvasica sp. nov., Agathammina darvasica sp. nov., Pachyphloia darvasica sp. nov., Nodosinelloides cubanicus elongatus subsp. nov., and Hemigordius saranensis darvasicus subsp. nov. are described.  相似文献   
8.
In recent years, the loess deposits in Central Asia have attracted increasing attention of Qua-ternary paleoclimate researchers[1—8]. The centre of the loess deposits in this area is located in southern Tajikistan, where thick and continuous loess sectio…  相似文献   
9.
Major chemical elements and Rb, Sr, Ba abundances were measured for loess samples from Chashmanigar loess-soil sequence in southern Tajikistan. And the degree of element loss and intensity of weathering of the samples were calculated. From these calculations we found that the paleosol horizons of the Chashmanigar section were chemically weathered to some extent and the weathering intensity of the soils is stronger than that of loess horizons, indicating that paleosols in southern Tajikistan were deposited in relatively warm and humid interglacial ages. In addition, the southern Tajikistan loess deposited before 0.9Ma BP was more intensely weathered than that deposited after 0.9Ma BP, which may imply the intensification of aridity in this area since 0.9Ma BP.  相似文献   
10.
本文系统归纳总结与对比分析了塔里木盆地、北阿富汗-南塔吉克斯坦盆地和卡拉库姆盆地的油气地质特征,并在此基础上探讨了该地区古生代以来地质演化对盆地演化和油气地质特征的控制作用。塔里木盆地奠基在前南华系结晶基底之上,中亚两个盆地奠基在南天山洋闭合之后形成的前二叠系褶皱基底之上。塔里木盆地的盖层沉积明显受到了南侧“原特提斯(北昆仑)”、古特提斯和新特提斯的影响,由于北昆仑带向西尖灭于北帕米尔,中亚两个含油气盆地的中-新生界则主要受到南侧古特提斯和新特提斯的影响。中亚两个盆地的海陆交互相和礁灰岩相侏罗系向东到塔西南相变为陆相,这从烃源岩的角度决定了塔西南与中亚两个盆地中-新生界不同的含油气性。塔里木盆地中-新生界有利的油气生储盖组合主要存在于前陆盆地的陆相地层中,它与下伏古生界含油气层系的叠加作用提高了其油气潜力。  相似文献   
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