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Geomorphologic evidence of phased uplift of the northeastern qinghai-Tibet Plateau since 14 million years ago

Science china Earth Sciences 2004年第9期47卷 822-833页

作者： LU Huayu1, WANG Xiaoyong1, AN Zhisheng1, MIAO Xiaodong1, ZHU Rixiang3, MA Haizhou2. LI Zhen4, TAN Hongbing2.& WANG Xianyan1 1. State Key Laboratory of Loess and Quaternary Geology, Institute of Earth Environment, Chinese Academy of Sciences, Xi’an 710075 china 2. qinghai Institute of Salt Lakes, Chinese Academy of Sciences.{2., china 3. Institute of Geology and Geophysics, Chinese Academy of Sciences, Beijing 10002., china 4. department of geography, qinghai normal University,{2., china Chinese Acad Sci Inst Earth Environm State Key Lab Loess & Quaternary Geol Xian 710075 Peoples R China Chinese Acad Sci Qinghai Inst Salt Lakes Xining 810008 Peoples R China Chinese Acad Sci Inst Geol & Geophys Beijing 100029 Peoples R China qinghai normal Univ Dept Geog Xining 810008 Peoples R China

A typical sequence of fluvial terraces and aeolian deposits overlying these ter- races were multidisciplinary investigated. New evidences for uplift process of the northeastern qinghai-Tibetan Plateau in the past 14 million years were obtained. At least 11 river terraces along Huangshui, the first-class tributary of Yellow River, at the xining-Huzhu region are identi- fied. While the first one (T1) is classified as an accumulation terrace, the others are all basement river terraces, which consist of the Tertiary sandstone and siltstone bedrock, fluvial gravel and pebbles and the overlying aeolian loess-Red Clay deposit. Samples from the aeolian deposits were examined for paleomagnetic stratigraphic reconstruction (1030 samples), luminescence dating (16 samples), magnetic susceptibility and grain-size distribution (more than 4000 sam- ples). The luminescence dating and stratigraphic correlation suggest that terraces of Tll, T10, T8, T7, T3, T2. T1 were formed at 14, 11.3, 1.55, 1.2. 0.15, 0.07 and 0.01 million years ago, re- spectively. Sedimentological analysis and geomorphological observation indicate that formation and evolution of these terraces were mainly driven by tectonic uplift. Therefore, the terrace se- quence provides an ideal geological record, of the uplift process of the northeastern during the past 14 million years, and the timings of the terraces formation are regarded as the timings of tectonic uplift. The significant uplifting events took place at 14, 11.3, 1.2.and 0.15 mil- lion years ago, respectively. The fluvial incision at the xining-Huzhu region is less than 100 m during a period of ~12.million years in the Miocene era (between the Tll and T9), while the Huangshui River had incised 432.m during the past 1.2.million years (from T7 to the present floodplain). The river incision process clearly demonstrates that accelerated rising of the north- eastern qinghai-Tibet Plateau during the late Cenozoic, and provides new evidence of previous thoughts

关键词： river terrace, tectonic uplift, loess-Red Clay, the past 14 million years, northeastern qinghai-Tibet Plateau.

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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, china 2. department of Urban and Resources Sciences, Nanjing University, Nanjing 2.0093, china 3. department of Earth Sciences, Nanjing University, Nanjing 2.0093, china 4. department of geography, Shaanxi normal University, Xi’an 710062. china 5. Institute of Geology and Geophysics, Chinese Academy of Sciences, Beijing 10002., china 6 department of geography, qinghai normal University, xining 810008, china 7. Graduate School of the Chinese Academy of Sciences, Beijing 100039, china 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 2. 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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Mo_(2.P Monolayer as a Superior Electrocatalyst for Urea Synthesis from Nitrogen and Carbon Dioxide Fixation:A Computational Study

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Energy & Environmental Materials 2024年第1期7卷 207-214页

作者： Dongxu Jiao Zhongxu Wang Yuejie Liu qinghai Cai Jingxiang Zhao Carlos R.Cabrera Zhongfang Chen College of Chemistry and Chemical Engineering and Key Laboratory of Photonic and Electronic Bandgap Materials Ministry of EducationHarbin Normal UniversityHarbin 150025China Modern Experiment Center Harbin Normal UniversityHarbin 150025China Heilongjiang Province Collaborative Innovation Center of Cold Region Ecological Safety Harbin 150025China department of Chemistry and Biochemistry The University of Texas at El PasoEl Paso TX 79968USA department of Chemistry University of Puerto RicoRio Piedras CampusSan JuanPuerto Rico 00931USA

Urea synthesis through the simultaneous electrocatalytic reduction of N_(2.and CO_(2.molecules under ambient conditions holds great promises as a sustainable alternative to its industrial production,in which the development of stable,highly efficient,and highly selective catalysts to boost the chemisorption,activation,and coupling of inert N_(2.and CO_(2.molecules remains rather ***,by means of density functional theory computations,we proposed a new class of two-dimensional nanomaterials,namely,transition-metal phosphide monolayers(TM_(2.P,TM=Ti,Fe,Zr,Mo,and W),as the potential electrocatalysts for urea *** results showed that these TM_(2.P materials exhibit outstanding stability and excellent metallic ***,the Mo_(2.P monolayer was screened out as the best catalyst for urea synthesis due to its small kinetic energy barrier(0.35 eV)for C-N coupling,low limiting potential(-0.39 V),and significant suppressing effects on the competing side *** outstanding catalytic activity of the Mo_(2.P monolayer can be ascribed to its optimal adsorption strength with the key^(*)NCON species due to its moderate positive charges on the Mo active *** findings not only propose a novel catalyst with high-efficiency and high-selectivity for urea production but also further widen the potential applications of metal phosphides in electrocatalysis.

关键词： C-N coupling density functional theory Mo_(2.P monolayer urea synthesis

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Study on sea water intrusion into palaeochannels on south coastal plain of the Laizhou Bay by the Bohai Sea

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Acta Oceanologica Sinica 2003年第1期22卷 69-74页

作者： Han Mei geography department, Shandong {2. University, Jinan 2.0014, china Shandong normal Univ Dept Geog Jinan 250014 Peoples R China

The palaeochannel evolution in the study region is divided into four stages by such methods as 14C dating. Sea water intrusion through palaeochannels has been studied as a focal point. Palaeochannels are the main passageways through which the sea water intrudes at a higher speed, through many means and in a changeable dynamic state.

关键词： Palaeochannel sea water intrusion south coastal plain of Laizhou Bay

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Geomorphologic evolution and environmental changes in the Shaluli Mountain region during the Quaternary

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Chinese Science Bulletin 2005年第1期50卷 52-57页

作者： ZHOU Shangzhe1,2. XU Liubing1, CUI Jianxin1, ZHANG Xiaowei1 & ZHAO Jingdong1 1. National Laboratory of Western china’s Environmental Systems of Ministry of Education of china and {2. of geography, Lan- zhou University, Lanzhou 730000, china 2. {2. of geography, South china normal University, Guang- zhou 510631, china National Laboratory of Western china''s Environmental Systems of Ministry of Education of china and {2. of geography Lanzhou University Lanzhou 730000 China department of geography South China Normal University Guangzhou 510631 China

Geologic and geomorphologic evidence from the Shaluli Mountain indicates that the planation surface that formed in the Late Tertiary disintegrated during the Late Pliocene-Early Quaternary. At the same time, rift ba- sins appeared on some parts of the planation surface, and began to accumulate fluvial-lacustrine sediment. These are interpreted as being the response of this region to Phase-A of the Qingzang Tectonic Movement. After this, the Shaluli Mountain continued to rise in several pulses. Faulting and incision by some large tributaries of the Jinsha and Yalong Rivers resulted in several rift river valleys and the earliest terraces. Generally, the planation surface in this region had been uplifted to about 3500—3700 m a.s.l. no later than 550—600 ka BP, after the Kunlun-Huanghe Tectonic Move- ment, and coupled with global glacial climate, and resulted in the earliest glaciation recognized so far in the Hengduan Mountains. At the same time, loess was deposited in the Ganzi area of the northern Shaluli Mountain. During the last glacial period, the Shaluli Mountain approached its present altitude and developed several large ice caps, such as the Daocheng Ice Cap and Xinlong Ice Cap, as well as several huge valley glaciers. These paleoglaciers produced some of the most spectacular glacial topography on the Tibetan Pla- teau.

关键词：地形学环境变化 Shaluli山脉展平面西藏高原 ESR-年代测定

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Formation and Evolution of Ancient Lakes on South Coast Plain of Laizhou Bay

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Chinese Journal of Population,Resources and Environment 2005年第4期3卷 26-32页

作者： Han Mei 1, Zhou Baohua 2. Yang Peilin 1,Gao Guiqin 1 & Zhang Weiying 1 1. department of geography, Shandong {2. University, Jinan 2.0014, china 2. department of geography, Jinan University, Jinan 2.0001, china department of geography Shandong Normal University Jinan 250014 China department of geography Jlnan University Jinan 250001 China

Based on the data of historical geography, the analysis of the stratigraphic section, and the textual research of place names and satellite photographic interpretations, the authors study the formation and evolution of ancient lakes on the south coast plain of Laizhou Bay where there were once three lakes: Judian Lake, Qingshuibo Lake and Biehua Lake. All the lakes formed 6000 years ago evolved from the lagoons near the estuary and went through two periods, the golden age in the Middle Holocene and the shrinking age in the Late Holocene. The disappearance of the lakes resulted from the drying climate, the migration of the river courses and the activities of human beings. Among the three reasons, the migration of the river courses is the main one.

关键词： ancient lake cause historical evolution south coast plain of Laizhou Bay

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Climate change tendency and grassland vegetation response during the growth season in Three-River Source Region

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Science china Earth Sciences 2010年第10期53卷 1506-1512页

作者： QIAN Shuan1,FU Yang2.& PAN FeiFei3 1 National Meteorological Center,Beijing 100081,china 2.qinghai Meteorological Research Institute,{2. 810001,china 3 department of geography,University of North Texas,Denton,TX 762.3,USA 1. National Meteorological Center Beijing 100081 China2. Qinghai Meteorological Research Institute Xining 810001 China3. Department of Geography University of North Texas Denton TX 76203 USA

Climate change,climate suitablity change for grassland vegetation,and grassland response to climate change during the growth season are studied systematically by using meteorological data of temperature,precipitation,and length of sunlight from 1961 to 2.07,NOAA/AVHRR NDVI from 1982.to 2.06,and observations of grass height,biomass,and coverage in enclosed grassland from 1994 to *** models are developed to evaluate climate change and the climatic suitability of grassland vegetation *** temperature,accumulative precipitation,and length of sunlight during the growth season increased from 1961 to 2.07 at rates of 0.2.°C/10 yr,2.32.mm/10 yr,and 2.81 h/10 yr,*** increase rates of ave-rage temperature between April and May,and between June and August are 0.17 and 0.30°C/10 yr;accumulative rainfall between April and May increased at a rate of 2.80 mm/10 yr,and accumulative rainfall between June and August decreased at a rate of 0.38 mm/10 yr;the increase rates of accumulative length of sunlight between April and May,and between June and August are 2.15 and 1.2.h/10 *** climatic suitability of grassland vegetation growth showed an increasing trend,and the increase rate between April and May is greater than that between June and *** NDVI observations from 1982.to 2.06 and measurements of grass height,dry biomass,and coverage from 1994 to 2.06 show that the climate change has resulted in an increase in plant productivity of the grassland in Three-River Source *** some protection measures are taken as soon as possible,the deteriorated grassland in Three-River Source Region can recover.

关键词： climate change climate suitability change grassland vegetation Three-River Source Region

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An approach to the design principles for indicator system of desertification degree

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Journal of Geographical Sciences 2000年第3期10卷 93-98页

作者： SUN Wu1, LI Sen2.(1. department of geography, South{2. normal University, Guangzhou 510631,{2. 2. department of geography, Foshan University, Foshan 52.00,{2.)

From the analysis on the problem of selection, data acquisition, quantification and accuracy check in the indicators to desertification degree both at home and abroad, one might conclude that in the existing assessment of desertification degree there is a prevailing tendency which is the substitution of absolute landscape for relative land degradation, namely, assessment of desertification degree is that of absolute landscape state to some extent. As a result the reassessment accuracy of desertification scope, damaging degree and control effect are affected. The regaining and establishment of the initial and final ecological datum level of land degradation are the prerequisite to the establishment of normal scientific indicator system. From the viewpoint of this three design principles of indicators to the desertification degree are put forward: the zonal principle of indicator systems decided by the ecological datum level corresponding to their bioclimatic zones, the hierarchical principle of indicator systems decided by different spatial scales and the resolutions of different sensors and principle of landscape types based on the 3S as core-indicator.

关键词： ecological datum level zonal principle hierarchical principle landscape-type principle

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Politeness Principle and the Choice of Address Forms in Intercultural Communication

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海外英语 2011年第9X期 289-290页

作者： TIAN Yan-ping(Foreign Languages department,qinghai {2. University,xining 810008,china) Foreign Languages department Qinghai Normal University Xining 810008 China

This paper makes a tentative study of the politeness strategies stressed in the choice of address forms in Chinese,American and Japanese culture under the guidance of Politeness Principle by Brown and *** a comprehensive analysis,It is concluded that the major function of English address forms is to indicate solidarity and realize positive politeness,In contrast,both Chinese and Japanese address forms emphasize deference and help achieve negative politeness;It is the author's hope that a better understanding of these addressing rules in different cultures will benefit effective use of these languages and help avoid miscommunication in intercultural communication.

关键词： politeness principle address forms positive politeness negative politeness intercultural communication

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A Complete Solution to the Chromatic Equivalence Class of Graph Bn-8,1,4

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Journal of Mathematical Research with Applications 2012年第3期32卷 253-268页

作者： Yaping MAO,Chengfu YE,Shumin ZHANG department of Mathematics,qinghai {2. University,qinghai 810008,P.R.china department of Mathematics Qinghai Normal University Qinghai 810008

Two graphs are defined to be adjointly equivalent if and only if their complements are chromatically *** the properties of the adjoint polynomials and the fourth character R;（G）,the adjoint equivalence class of graph B;is *** to the relations between adjoint polynomial and chromatic polynomial,we also simultaneously determine the chromatic equivalence class of B;that is the complement of B;.

关键词： chromatic equivalence class adjoint polynomial the smallest real root the fourth character.

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