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Origin of the Red Earth sequence on the northeastern Tibetan Plateau and its implications for regional aridity since the middle Miocene

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Science china Earth sciences 2006年第5期49卷 505-517页

作者： WANG Xianyan1,7, LU Huayu1,2, JI Junfeg3. WANG Xiaoyong1,7, ZHAO Jingbo4. HUANG Baochun5 & LI Zhen6 1. SKLLQG, institute of Earth Environment, Chinese academy of sciences, Xi’an 710075,{3. 2. Department of Urban and Resources sciences, nanjing University, nanjing 210093.{3. 3. Department of Earth sciences, nanjing University, nanjing 210093.{3. 4. Department of geography, Shaanxi Normal University, Xi’an 710062,{3. 5. institute of Geology and Geophysics, Chinese academy of sciences, Beijing 100029,{3. 6 Department of geography, Qinghai Normal University, Xining 810008,{3. 7. Graduate School of the Chinese academy of sciences, Beijing 10003.,{3. 1. SKLLQG Institute of Earth Environment Chinese Academy of Sciences Xi’an 710075 China 7. Graduate School of the Chinese academy of sciences Beijing 100039 China 2. Department of Urban and Resources sciences Nanjing University Nanjing 210093 China 3. Department of Earth sciences Nanjing University Nanjing 210093 China 4. Department of geography Shaanxi Normal University Xi’an 710062 China 5. institute of Geology and Geophysics Chinese Academy of Sciences Beijing 100029 China 6. Department of geography Qinghai Normal University Xining 810008 China

The Red Earth deposit around Xining, northeastern Tibetan Plateau, has beenstudied in terms of soil micro-structure, grain-size distribution, major- and trace-elementchemistry and magne-tostratigraphy. Field investigations indicate that the Red Earth sequenceconsists of 25 visually definable yellow-brown and weakly-developed soils interbedded with reddishstrongly-developed soils, and has a similar structure to the aeolian Red Clay deposit on the ChineseLoess Plateau. Grain-size analysis shows that the Red Earth deposit is very fine-grained with anegligible sand fraction ( > 63.μm). Thin-section observations under light microscopy show that thedeposit has a clayey texture and the coarse fraction ( > 10 μm) mainly consists of quartz,feldspar and micas. Pyroxene and hornblende were also observed. This mineralogical composition ofthe coarse fraction is similar to that of the Quaternary loess. In addition, all of the mineralgrains are semi angular semi-angular and are generally finer than 63.μm. There is a good agreementbetween the major and minor trace element chemistry of loess-soil units and the Red Earth *** REE distributions of the loess-soil and the Red Earth deposit are similar in shape, withenriched LREE and fairly flat HREE profiles and a clear negative Eu anomaly. The geochemicalcharacteristics of the Red Earth deposit are also identical to those of upper continental crust,thus indicating a wind-blown origin. Magnetostratigraphic investigation shows that onset of the RedEarth deposition predates 11.4.Ma BP (13.6 Ma at a nearby site). The distribution of the reportedMiocene aeolian loess at Qin''an of the Loess Plateau is still unknown. Our results indicate thatthis aeolian deposit had extended to the northeastern Tibetan Plateau by at least the middleMiocene. The similarity of the element geochemistry between the Red Earth deposit and the overlyingloess shows that they may have similar sources and dynamic transport system, and may indicate thatthe

关键词： Red Earth deposit, Northeastern Tibetan Plateau, aeolian deposit, aridity of Asia, the middle Miocene.

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Chronology of Holocene lacustrine sediments in Co Ngoin, central Tibetan Plateau

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Science china Earth sciences 2006年第9期49卷 991-1001页

作者： WU Yanhong1, WANG Sumin1& HOU Xinhua1,3.1. Key Laboratory of Lake Sedimentation and Environment, nanjing institute of geography and {3., Chinese academy of sciences, nanjing 2.0008, china 2. institute of Tibetan Plateau Research, Chinese academy of sciences, Beijing 10085, china 3. Graduate University of Chinese academy of sciences, Beijing 10003., china 1. Key Laboratory of Lake Sedimentation and Environment Nanjing Institute of Geography and Limnology Chinese Academy of Sciences Nanjing 210008 China 2. institute of Tibetan Plateau Research Chinese Academy of Sciences Beijing 10085 China 3. Graduate University of Chinese academy of sciences Beijing 100039 China

Chronology is the basis for using lacustrine sediments to reconstruct the history of en-vironmental change. Radioactive-nuclides such as 14., 210Pb and 13.Cs dating are mainly used to establish the chronology for recent several ten thousand years. Because of being mixed with “dead carbon”, the measured 14. age is always older than the actual age which is recognized as “reservoir effect”. Cs is a kind of active metal element, and easy to migrate vertically in the sediment that leads to the error of the time marker. 210Pb dating should make sure to select CIC model or CRS model. On the Tibetan Plateau, most of the lakes are alkaline closed lake where Cs is more moveable in the sediment and the reservoir effect caused by “dead carbon” on 14. dating is stronger. Based on the analysis on results of 14., 210Pb and 13.Cs of the lacustrine sediments from Co Ngoin, central Tibetan Plateau, we use the simple regression method to re-calculate the 14. calendar ages, and establish the time sequence for cores CE-1 and CE-2 with result of 210Pb CRS model for the upper 3. cm and re-calculated 14. calendar age for sediments bellow 3. cm. Since 14.0 cal. a BP, sedimentation inter-rupted for more than 1000 years. According to this time sequence, variations of environmental proxies confidently reflect the major climatic events in Holocene.

关键词： 14., 210Pb and 13.Cs, chronology, lacustrine sediments, climatic event, Co Ngoin, central Tibetan Plateau.

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Effect of sediment resuspension on underwater light field in shallow lakes in the middle and lower reaches of the Yangtze River:A case study in Longgan Lake and Taihu Lake

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Science china Earth sciences 2006年第z1期49卷 114-125页

作者： ZHANG Yunlin, QIN Boqiang, ZHU Guangwei, GAO Guang, LUO Liancong & CHEN Weimin nanjing institute of geography & {3., Chinese {4. of sciences, nanjing 2.0008, china Graduate School of Chinese {4. of sciences, Beijing 10003., china 1. nanjing institute of geography & {3. Chinese Academy of Sciences Nanjing 210008 China 2. Graduate School of Chinese academy of sciences Beijing 100039 China

Based on three continuous in situ underwater light field measurement under different wind waves conditions in Longgan Lake, Meiliang Bay of Taihu Lake in July 2003.and littoral zone near TLLER in July 2004. respectively, the effects of sediment resuspension caused by wind waves on PAR diffuse attenuation, absorption coefficients and euphotic depths are analyzed. In Longgan Lake, PAR diffuse attenuation coefficients during small, middle and large wind waves were 1.74. 2.02 and 2.4. m-1, respectively, and the corresponding PAR spectral diffuse attenuations ranged from 0.98 to 2.97, 1.3. to 3.95 and 1.80 to 5.4. m-1, respectively. In Meiliang Bay, PAR diffuse attenuation coefficients were 2.63. 3.72, 4.3. m-1 during small, middle and large wind waves. PAR diffuse attenuation coefficients increased by 4.% and 66% from small to middle, large wind waves, respectively. Absorption coefficients integrated over the range of PAR of CDOM, phytoplankton were 0.26, 0.28 m-1; 0.76, 0.4. m-1, respectively during middle and large wind waves. Absorption coefficients integrated over the range of PAR of non-algal particulate matter and total suspended particulate matter increased from 0.94.to 1.73.m-1, and from 1.70 to 2.22 m-1, respectively during middle and large wind waves. Relative contributions of absorption coefficients of non-algal particulate matter to total absorption coefficient integrated over the range of PAR were 4..14., 65.05%, respectively, during middle and large wind waves. PAR euphotic depths decreased by 0.4., 0.19, 0.20 m from middle to large wind waves in Longganhu Lake, Meliang Bay and littoral zone near TLLER. Significant correlations were found between transparency, PAR diffuse attenuation coefficients, euphotic depths and total suspended paniculate matter, wind velocity, wave height. Most significant correlations were found between transparency, PAR diffuse attenuation coefficients, euphotic depths and inorganic suspended paniculate matter but low correlations

关键词： shallow lake, Taihu Lake, diffuse attenuation coefficient, absorption coefficient, total suspended particulate matter.

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Research on the evaluation model of the modernization level of urban construction in Jiangsu Province,china

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Science china(Technological sciences) 2010年第9期53卷 2510-2514页

作者： YANG JunYan1 & CHEN Wen2 1 School of Architecture,Southeast University,nanjing 210096,china 2 nanjing {3. of {4. and limnology,Chinese academy of sciences,nanjing 2.0008,china 1. School of Architecture Southeast University Nanjing 210096 China2. Nanjing Institute of Geography and Limnology Chinese Academy of Sciences Nanjing 210008 China

The modernization of urban construction is a key index in the process of urbanization,and also is an important index to measure the level of socio-economic and cultural *** paper analyzes and explores the related concepts of modernization of urban construction,analyzes the situation and identity of urban construction layer by layer so as to establish an evaluation index system of the modernization level of urban construction and then the paper evaluates the modernization level of urban construction from four different angles,which are the perspectives of the urban planning control,the level of urban facilities,urban management,urban construction *** later analyzes the evaluation results by choosing Jiangsu Province as a research hierarchy from the scale chains of urban study and makes efforts to the operative and directive development direction.

关键词： modernization of urban construction index system evaluation model

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APPLICATION　OF　GIS　IN　ANALYZING　ECOSYSTEM＇S　RELATIVE　SENSITIVITY　TO　ACID　DEPOSITION

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Chinese Geographical Science 1996年第4期6卷 359-363页

作者： He Longhua Yans Hongwei(nanjing institute of geography & {3., the Chinese {4. of sciences,nanjing 2.0008, PRC) nanjing institute of geography & {3. the Chinese Academy of Sciences Nanjing PRC

This paper decribo an application of GIS technology in estimating estem's relive sensitivity to acid despition. East china is selected as the research area. Four variable layers, which are ha rock, soil buffering ability, vegetation type and soil humidity, are used in the process. Five grades are separated in this research. The sensitivity mapping is also discussed in this paper.

关键词： acid deposition sensitivity index geographic information system

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Nutrient fluxes induced by disturbance in Meiliang Bay of Lake Taihu

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Science china Earth sciences 2006年第z1期49卷 186-192页

作者： LUO Liancong, QIN Boqiang, ZHU Guangwei, SUN Xiaojing, HONG Dalin, GAO Yajun & XIE Rui nanjing institute of geography & {3., Chinese {4. of sciences, nanjing 2.0008, china nanjing Hydraulic Research institute, Ministry of Water Resources, nanjing 210024. china 1. nanjing institute of geography & {3. Chinese Academy of Sciences Nanjing 210008 China2. Nanjing Hydraulic Research Institute Ministry of Water Resources Nanjing 210024 China

A wave flume experiment was conducted to study nutrient fluxes at water-sediment interface of Meiliang Bay under different hydrodynamic conditions. The results reveal that hydrodynamics has remarkable effects on nutrient fluxes in this area. With a bottom wave stress of 0.019 N m-2 (equivalent to disturbance caused by wind SE 5-7 m s-1 at the sediment sample site of Meiliang Bay), the fluxes of TN, TDN and NH4.-N were separately 1.92× 10-3. -1.81 × 10-4.and 5.28× 10-4.mg m-2 s-1(positive for upward and negative for downward), but for TP, TDP and SRP, the fluxes were 5.69 × 10-4. 1.68 × 10-4.and -1.29 × 10-4.mgm-2 s-1. In order to calculate the released amount of nutrients based on these results, statistic analysis on the long-term meteorological data was *** result shows that the maximum lasting time for wind SE 5-7 m s-1 in this area is about 15 h in summer. Further calculation shows that 111 t TN, 3. t NH4.-N, 3. t TP and 10 t TDP can be released into water (the sediment area was 4..4.% of the whole surface area), resulting in concentration increase of 0.025, 0.007, 0.007 and 0.002 mg L-1 separately. With stronger disturbance (bottom wave stress is 0.217 N m-2 which is equivalent to disturbance caused by wind SE 10-11 m s-1 at the same site), there has been significant increase of nutrient fluxes (1.16× 10-2, 6.76×10-3. 1.14. 10-2 and 2.14. 10-3.mgm-2 s-1 for TN, DTN and NH4.-N and TP). The exceptions were TDP with flux having a decrease (measured to be 9.54. 10-5 mgm-2 s-1 ) and SRP with flux having a small increase (measured to be 5.4. × 10-5 mgm-2 s-1). The same statistic analysis on meteorological data reveal that the maximum lasting time for wind SE 10-11 m s-1 is no more than 5 h. Based on the nutrient fluxes and the wind lasting-time, similar calculations were also made suggesting that 23. t TN, 13..9 t TDN, 228 t NH4.-N, 4..7 t TP, 2.0 t TDP and 1.1 t SRP will be released from sediment at this hydrodynamic condition resulting in the concentration

关键词： hydrodynamics disturbance water-sediment interface nutrient release flux Lake Talhu.

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Geophysical survey on the tectonic and sediment distribution of Qinghai Lake basin

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Science china Earth sciences 2006年第8期49卷 851-861页

作者： AN Zhisheng1, WANG Ping2, SHEN Ji3. ZHANG Yixiang2, ZHANG Peizhen4. WANG Sumin3. LI Xiaoqiang1, SUN Qianli1, SONG Yougui1, AI Li1, ZHANG Yechun2, JIANG Shaoren2, LIU Xingqi3.& WANG Yong3.. {4. of Earth Environment, Chinese academy of sciences (CAS), Xi’an 710075,{3. 2. South{3. Sea {4. of Oceanology, CAS, Guangzhou 5103.1,{3. 3. nanjing institute of geography and limnology, CAS, nanjing 2.0008,{3. 4. {4. of Geology,{3. Earthquake Administration, Beijing 100029,{3. 1. institute of Earth Environment Chinese Academy of Sciences (CAS) Xi’an 710075 China 2. South china Sea institute of Oceanology CAS Guangzhou 510301 China 3. nanjing institute of geography and limnology CAS Nanjing 210008 China 4. institute of Geology China Earthquake Administration Beijing 100029 China

The intensive geophysical survey of Qinghai Lake reveals the buried depth of lake sediments and their distribution features. The result indicates that there are three important inter- phases of Qinghai Lake sediments: T1 is the rife interphase of the lake, above which sediments are spread all over the lake basin with roughly the same thickness; T5 is the interphase from which the neotectonic sedimentary cycle begins, and its above sedimentary environment is relatively stable; Tg is the base of the lake basin. Five west-northwest (WNW) fault belts defined the tectonic structure of Qinghai Lake basin: the central hunch around Haixin Shan with two subbasins both in its north and south. The thickness of the lake sediments varies at different places, the thickest sediments are found within the two subbasins. According to the depth that the Sparker System can reach, sediment in the northern subbasin is deeper than 560 m, while sediment in the southern subbasin is deeper than 700 m. The correlation between the seismic sequence stratigraph and the lithology of onshore core shows that Qinghai Lake sediments consist of muddy silt, clay silt, silty clay, gravel silty clay, etc.

关键词： sediment, geophysical survey, Qinghai Lake.

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Effects of main range and strength factors on change of COD in a shallow lake

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Journal of Environmental sciences 1998年第1期10卷 51-57页

作者： Fan Cheng xin nanjing institute of geography and {3.,Chinese {4. of sciences,nanjing 2.0008,china

A model involving the relationship between non conservative matter (COD) and main range factors(loading, water stage) and strength factor (temperature) in a shallow lake has been established on the basis of less change of water stage area curve in certain extent, broader distribution in pollution sources and more homogeneous in quantity of heat. The effects of COD inflow and /or outflow, and hydro meterological factors upon COD content in Lake Taihu were calculated and simulated under the actual situation of the loadings and regimen. The results simulated by using the model are in better agreement with the observed field data. The error of the model was also discussed.

关键词： COD model environmental factor effects shallow lake.

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MAJOR PROBLEMS OF SUSTAINABLE DEVELOPMENT ALONG THE BANK AREA OF THE CHANGJIANG RIVER

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Chinese Geographical Science 2000年第2期10卷 97-104页

作者： YANG Gui-shan(nanjing institute of geography and {3.,the Chinese {4. of sciences, Nanjng 2.0008, P R. china) nanjing institute of geography and {3. the Chinese Academy of Sciences Nanjing P. R. China

Developing the Changjiang(Yangtze) River and building a developed economic zone along the bank area of the Chanajiang River is a great strategic decision of the national macroeconomic development distribution. This decision has both given an impetus to fast development of the regional economy and exacerbated the contradiction among economy and resources and environment. In this paper, some major problems ekisting in economic sustainable development, such as scattered industrial structure, duplicated construction of the great projects, enlarging the development gap of the regional economy and deteriorated environment etc., have been studied. The results show that scattered structure and duplicated distribution of some key industries and projects, especially automobile, electronics and petrochemical industry and communication, power installations, is one of the reasons for low industrial economic benefit; the great development gap among upper, middle and lower reaches areas are enlarging since the 1990’ s; soil erosion, nood disaster and environmental pollution are still exacerliating due to unreasonable over-development. Based on the above analysis, this paper brings out some countermeasures and proposals for increasing the ability of regional sustainable development, including transregional reorganization of industrial structure linking by assets and speeding the process of regional economy integration; gradually controlling and reducing the development gap arnong upper, middle and lower reaches areas through regional cooperation on a mutually beneficial basis; as well as strengthening ecological construction and environmental protection and increasing environmental bearing capacity etc.

关键词： the bank area of the Changjiang River sustainable development structure problems environment deterioration

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THE CHARACTERISTICS AND MAIN PROBLEMSOF MINORITY REGIONS IN china

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Chinese Geographical Science 2001年第4期11卷 8-13页

作者： ZHANG Luo-cheng, WU Chu-cai(nanjing institute of geography & {3., the Chinese {4. of sciences, nanjing 2.0008, P. R. china) nanjing institute of geography & {3. the Chinese Academy of Sciences Nanjing P. R. China

ABSTRACT: china is a country that has a large number of minorities, who live in specific regions which are mainly located in central and west china. These regions are abundant in natural resources, which are potential advantages and also an important basis for economic development in these regions. They are of general importance for china in strategic and ecological terms. They will not only affect the environment for survival of the minority regions but also affect the sustainable development of the eastern and central parts of china and even the survival and development of the Chinese nation as a whole. Minorities live in relatively compact communities, among the 55 minorities, {4. of them were highly compact minorities, with a compact level of more than 90% . Here the development in infrastructure as well as social and economic development (e. g. export-oriented economy) has been and is still slow, regional poverty are most concentrated. The economic structures in minority areas are still in the low stage, which have resulted in underdevelopment in these regions.

关键词： minority regions development problems

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