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Gravity field and crustal structure of Gyirong-Lugu Region in western xizang (Tibet) Plateau

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Chinese Science Bulletin 1997年第8期42卷 669-673页

作者： Wang, QS Wu, CZ Jiang, WW Institute of Geophysics Chinese Academy of Sciences Beijing China

THE Gyirong-Lugu gravity profile in western xizang Plateau was carried out by Institute ofGeophysics,Chinese Academy of Sciences in 1994—*** data of this gravity profile fillthe gaps in the research of gravity field of western xizang Plateau and provide basic informa-tion for the study of the whole structure and dynamical mechanism of xizang Plateau.

关键词： western xizang Plateau Gyirong-Lugu region gravity crustal structure.

THE　CAUSES　AND　DEVELOPMENTAL　TREND　OF　DESERTIFICATION　IN　THE　MIDDLE　REACHES　OF　THE　YARLUNG　ZANGBO　RIVER　AND　ITS　TWO　TRIBUTARIES　IN　xizang

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Chinese Geographical Science 1995年第4期5卷 355-364页

作者：董光荣董玉祥李森金炯靳鹤龄刘玉璋 Institute of Desert Research the Chinese Academy of Sciences Lanzhou PRC

The middle reaches of the Yarlung Zangbo River and its two tributaries are an important development and construction region in xizang(Tibet) in recent years, but the fast development of desertification has caused immense damages to its social and economic development, so the study on desertification in this region is significant. The paper studies the causes and development trend of desertification in this region through analysis of natural and human factors as well as their relationship. It can be concluded that desertification in the study area is one process which is accelerated and intensified by human activities on the basis of the slow natural desertification process. It is resulted from the dislocation of irrational and intensive human activities, fragile eec-environment and meagre natural resources, and tends to become more wide and severe.

关键词： desertification eco-environment the Yarlung Zangbo River xizang

THE FLORISTIC STRUCTURE OF THE xizang PART OF THE QINGHAI-xizang PLATEAU PLANT SUBKINGDOM

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Chinese Geographical Science 1991年第3期1卷 27-39页

作者：李恒武素功 Kunming Institute of Botany Academic Sinica Kunming PRC

The flora of the Qinghai-xizang Plateau belongs to the floristic subkingdom of the Holarctic plant kingdom. The xizang part of this subkingdom can be divided into 4 plant regions. 1) the Yarlung Zangbo River valley region. There are 1,003 species of seed plants, making up 19.38% of the total species in xizang, and 159 endemic species, 15.89% of the total seed plants. The flora originates mainly from the East Himalayas and the Hengduan Mountains. 2) The Tanggute region. There are 349 species of seed plants and 10 endemic species. The flora represents an intermediate one between the Qinghai-xizang Plateau and the Hengduan Mountains.3) The Qiangtang region. There are 255 species of seed plants and 18 endemic species. The flora derived from the Himalayan flora and mixed with a great number of Tethysian elements. 4) the Ali region. There are 547 species of seed plants and 41 endemic species. The flora seems to be closely related to Tethysian one.

关键词： floristic structure Qinghai-xizang Plateau plant subkingdom xizang

KINEMATIC FEATURES OF TECTONIC DEFORMATION OF TERRANES IN THE xizang (TIBETAN) TETHYAN BELT

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地震地质 1992年第3期 204-214页

作者： Shen Xianjie(Institute of Geology,Academia Sinica,Beijing 100029)

From the point of view of plate kinematics a unified convergence velocity model is employed to derive a series of kinematic equations for deformation of Himalaya and Lhasa-Gangdise terranes during the Himalayan *** equations describe terrane shortening,crust-upper mantle thickening,lateral strike-slip movement,plateau surface uplift,erosion planation and isostatic height of the crust,*** kinematic equations for terrane deformation derived on the basis of mass conservation define the macroscopic trends of tectonic evolution of 2-D deformation of the Himalaya Terrane and 3 D deformation of the Lhasa-Gangdise Terrane during the 40Ma of the Indian-Eurasian convergence-collision on the one hand,and provide the systematically defined initial and boundary conditions for further study on the process of tectono-thermal evolution of the deformed terranes on the other hand.

关键词： Tethyan Belt Terranes Tectonic deformation Plate kinematics Mass conservation xizang

CHARACTERISTICS AND RATIONAL EXPLOITATION OF LAND RESOURCES IN xizang

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Chinese Geographical Science 1996年第4期6卷 321-331页

作者： Li Mingsen (Commission for Integrated Survey of Natural Resources,the Chinese Academy of Sciences, Beijing 100101, PRC) Commission for Integrated Survey of Natural Resources the Chinese Academy of Sciences Beijing PRC

There is vast land in xizang (Tibet), but the land suitable for agriculture is less and concentrated. There is a large quantity of land suitable for animal husbandry, but great differentiation in quality. The land suitable for forestry is in large quantity and high quality. The land in high, cold and dry region is very difficult for use. An of these chacteristics determine the Pedctive structure and scale and the distribution of agriculture, forestry and animal husbandry in xizang. At present, the exploitation level of land resources in xizang is low, the commodity production is backward and some of the land is in degradation. The exploitstion should be combined with the conservation of several kinds of land resources. Per unit pleduction of land staid be enhanced, the improvement of the grassland and the construction of artificial grassland should be carried out. They are the strategy and effective countermeasures for the improcement of economy, production conditions and the eco-environment in xizang.

关键词： land resources productive potentiality xizang land exploitation

DISTRIBUTION CHARACTERISTICS OF BORON AND LITHIUM IN BRINE OF ZHACANG CAKA SALT LAKE, xizang (TIBET), CHINA

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Chinese Journal of Oceanology and Limnology 1984年第2期2卷 218-227页

作者： Zheng Xiyu (Institute of Salt Lake, Academia Sinica, Xining) Institute of Salt Lake Academia Sinica Xining

1. Composition of the Brine The specific gravity of its surface brine is from 1.073 to 1.291. Its salinity is 230-350 g/L. It consists of more than 30 elements, such as Na+, K+, Mg++, Ca++, Cl-,. SO4-, HCO3-, etc. It is also highly mineralized with rich B, Li, and Rb.2. Description of the Lake This saline lake belongs to the sulfate type, of which lake I and lake II are of Na2SO4 subtype and lake III of MgSO4 subtype.3. The Distribution Characteristics of B and Li in the Lake (1) The concentrations of B and Li are higher than that in sea water, B being 78-121 times higher, Li being 2625-4000 times higher. (2) A striking enrichment area of B and Li was formed in this brine lake. (3) The concentrations of B and Li are related to total mineralization of this lake.

关键词： Li Lake DISTRIBUTION CHARACTERISTICS OF BORON AND LITHIUM IN BRINE OF ZHACANG CAKA SALT LAKE TIBET xizang CHINA

A STUDY ON THE SPATIAL DIFFERENTIATION AND THE DIVISION OF FLORISTIC PHYTOGEOGRAPHY OF xizang(TIBET)

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Journal of Geographical Sciences 1991年第1期2卷 29-39页

作者： Zheng Du Institute of Geography CAS

An approach on the floristic differetatiation and division of xizang has been made in the present paper using a quantitative floristic *** to areal types of the *** flora of xizang may be classifed intO five majorgeographicalelements:theNorthTemperate(N),Central Asiatic(C),Tibetan Plateau(T),*** fSH),and theTropical(Tr).Threecross-sectionswerechosenforiUustmting the spatial floristic *** is obvious that the SH-element prevails in the eastern and southeastern xizang and the Tr-element is confined at lower elevations of the southern llanks of the *** the contranry,the T-element dominates on the Plateau proper and the *** plays a significant role in the northwestern part of *** the basis *** spectra of the floristic elements,four floristic boundaries are defined,which separate difierent floristic regions from one another,and a tentative scheme of floristic division of xizang has been proposed.

关键词： xizang geographical elements offlora areal spectra spatial differentiation floristic division

FLOROGEOGRAPHY OF MIRE PLANTS IN SOUTHERN PART OF QINGHAI-xizang PLATEAU AND ITS ADJACENT AREAS

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Chinese Geographical Science 1998年第1期8卷 45-53页

作者：赵魁义

The southern part of the Qinghai xizang (Tibet) Plateau and its adjacent area are rich in mire flora. There are 51 families, 101 genera and 220 species. The geographical compositions of this region are very complex, consisting of the following geographical elements: tropic subtropic elements approximating to 8.33% of the entire flora in the region, tropic temperate elements 22.71%, temperate elements 43.18%, cosmopolitan elements 9.85%, the Qinghai xizang endemic elements 14.39%, north polemountain elements 1.51%. Temperate elements in this region are dominant. The dominant species of mires, Carex lasiocarpa, in this region is also found in northeast China, Finland and North America. The origin of mires of this region is earlier than northeast China and Finland. This shows that the southern part of the Qinghai xizang Plateau and its adjacent areas may be the centre of the origin and distribution of temperate elements.

关键词： florogeography mire plant the Qinghai xizang Plateau

THE ANISOTROPY OF LOESS MAGNETIC SUSCEPTIBILITY IN THE NORTHEASTERN FRINGE OF QINGHAI-xizang PLATEAU AS AN INDICATOR OF PALAEOWIND DIRECTION

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Chinese Geographical Science 1998年第1期8卷 86-91页

作者：王建力

Estimates of the palaeo subaerial wind direction were studied systematically for the first time by using the anisotropy of loess magnetic susceptibility (AMS) measurements in the northwestern China. One hundred and forty undisturbed oriented aeolian loess samples were collected from Lanzhou, Linxia and Wudu areas for AMS measurements, which indicated the subaerial wind directions were not the same while the loess deposited. From the Early Pleistocene to Middle Pleistocene till Late Pleistocene, the wind direction experienced an anticlockwise rotation in the studied area. We suggested this change was related to the uplift of the Qinghai xizang Plateau and the adjustment of current and landform effects.

关键词： anisotropy of magnetic susceptibility palaeo wind direction uplift of the Qinghai xizang Plateau