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Variations of near-surface atmospheric CO_(2.and H_(2.O concentrations during summer on Muztagata

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Science china Earth Sciences 2006年第1期49卷 18-26页

作者： XU Baiqing1,2. YAO Tandong1,2. LU Anxin2. GUO Xuejun, LIU Xianqin2.& LI Zhen2.1. Laboratory of Environment and Process on Tibetan Plateau, institute of Tibetan Plateau research, Chinese Academy of Sciences, Beijing 100085,{2. 2. Key Laboratory of Cryosphere and Environment, Jointly Established by Cold and Arid Regions Environmental and Engi-neering research institute and institute of Tibetan Plateau research, Chinese Academy of Sciences and Chinese Academy of Meteorological Sciences,{2. Meteorological Administration, lanzhou 73.000,{2. Laboratory of Environment and Process on Tibetan Plateau Institute of Tibetan Plateau Research Chinese Academy of Sciences Beijing China Key Laboratory of Cryosphere and Environment Jointly Established by Cold and Arid Regions Environmental and Engineering Research Institute and Institute of Tibetan Plateau Research Chinese Academy of Sciences and Chinese Academy of Meteorological Sciences China Meteorological Administration Lanzhou China

Expeditions during the summers of 2.02.and 2.03 implemented continuous monitoring of near-surface (2.m height) atmospheric CO2.and H2. concentrations at the 4500 m elevation on Muztagata. The resultant data sets reveal a slight decrease of CO2.concentrations (of about 5 μmol·mol?1) and changes in the diurnal variations from the end of June to the middle August. The daily maximum CO2.concentrations occur between 02.30―05:30 AM (local time) and the minimum levels occur between 12.00―15:30 PM. The atmospheric CO2.concentrations in the summer of 2.02.were around 5 μmol·mol?1 lower than those during the same period of 2.03, whereas the diurnal amplitude was higher. In contrast, we found that the daily mean atmospheric H2. content in 2.03 was much lower than that in 2.02.and there exists a striking negative correlation between CO2.and H2. con-centrations. We therefore suggest that the near-surface atmospheric CO2.concentration is affected not only by photosynthesis and respiration, but also by the air H2. content in the glaciated region around Muztagata.

关键词： atmospheric CO2 and H2. concentration, continuous monitoring, glaciation region, Muztagata.

林克明旧居修缮与活化利用,广州,广东,中国

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世界建筑 2024年第8期 64-69页

作者： Guangdong Architectural Design and research institute Group Co.,Ltd. Architectural Design and research institute of South china University of Technology 广东省建筑设计研究院集团股份有限公司华南理工大学建筑设计研究院有限公司

街区断点更新林克明旧居(简称旧居)1935年由中国第一代著名建筑师林克明设计建造。旧居所在的越秀北路原为民国初年广州城墙拆除后的城基路,城外即东濠涌,前后高差达8m。林克明巧妙地利用地形组织功能与空间,并采用摩登建筑理念,使建筑... 详细信息

街区断点更新林克明旧居(简称旧居)1935年由中国第一代著名建筑师林克明设计建造。旧居所在的越秀北路原为民国初年广州城墙拆除后的城基路,城外即东濠涌,前后高差达8m。林克明巧妙地利用地形组织功能与空间,并采用摩登建筑理念,使建筑形体呈现出迷人的风采。

关键词：建筑形体建筑理念活化利用功能与空间著名建筑师林克明修缮城墙

Hydrogen isotopic characteristics and their genetic relationships for individual n-alkanes in plants and sediments from Zoigê marsh sedimentary environment

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Science china Earth Sciences 2010年第9期53卷 1329-1334页

作者： DUAN Yi1, ZHENG ChaoYang2.& WU BaoXiang1 1 Key Laboratory of Petroleum Resources research, institute of Geology and Geophysics, Chinese Academy of Sciences,{2., china 2.Department of Geology, Northwest University, Xi’an 710069, china Key Laboratory of Petroleum Resources research Institute of Geology and Geophysics Chinese Academy of Sciences Lanzhou China Department of Geology Northwest University Xi’an China

To understand internal relations of their hydrogen isotopic compositions in typical marsh environment, we, using GC-IRMS analytical technique, measured the hydrogen isotopes of individual n-alkanes in the herbaceous plant, woody plant leaf, and sediments from Zoigê marsh in china. The results show significant differences in the hydrogen isotopic compositions of n-alkanes among the different kinds of plants and the different species in the same kind. δD values of n-alkanes in the herbaceous plants (from -2.4‰ to -184‰) are lighter than those in woody plant leaf ( from -195‰ to -142. ), and the hydrogen isotopic compositions of n-alkanes in K. tibetica P. are lighter than P. pratensis L. The mean δD values of n-alkanes in the sediments from Zoigê marsh reflect that they were derived from herbaceous plants, which is consistent with the peat samples being composed mainly of herbaceous plant remnants. The significant differences in hydrogen isotopic compositions of n-alkanes among the sedimentary samples are caused possibly by environment factors and the difference in input quantity of different herbaceous plants. A certain negative correlation exists between the δ13C and δD values of n-alkanes in the samples, and plant types can be distinguished using the cross plot of δD vs. δ13C values of n-alkanes in the plants. These data and recognitions provide scientific basis for hydrogen isotopic applied research of individual n-alkanes.

关键词： marsh environment plants sediments individual lipids hydrogen isotopes genetic relationship

A land surface model incorporated with soil freeze/thaw and its application in GAME/Tibet

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Science china Earth Sciences 2006年第12期49卷 1311-1322页

作者： HU Heping1, YE Baisheng2. ZHOU Yuhua3 & TIAN Fuqiang1 1. Department of Hydraulic Engineering, Tsinghua University, Beijing 100084, china 2. Cold and Arid Regions Environmental and Engineering research {2., Chinese Academy of Sciences, lanzhou 73.000, china 3. Department of Civil Engineering, Massachusetts {2. of Technology, USA Department of Hydraulic Engineering Tsinghua University Beijing China Cold and Arid Regions Environmental and Engineering research institute Chinese Academy of Sciences Lanzhou China Department of Civil Engineering Massachusetts Institute of Technology USA

Land surface process is of great importance in global climate change, moisture and heat exchange in the interface of the earth and atmosphere, human impacts on the environment and eco- system, etc. Soil freeze/thaw plays an important role in cold land surface processes. In this work the diurnal freeze/thaw effects on energy partition in the context of GAME/Tibet are studied. A sophisti- cated land surface model is developed, the particular aspect of which is its physical consideration of soil freeze/thaw and vapor flux. The simultaneous water and heat transfer soil sub-model not only reflects the water flow from unfrozen zone to frozen fringe in freezing/thawing soil, but also demon- strates the change of moisture and temperature field induced by vapor flux from high temperature zone to low temperature zone, which makes the model applicable for various circumstances. The modified Picard numerical method is employed to help with the water balance and convergence of the numerical scheme. Finally, the model is applied to analyze the diurnal energy and water cycle char- acteristics over the Tibetan Plateau using the Game/Tibet datasets observed in May and July of 1998. Heat and energy transfer simulation shows that: (i) There exists a negative feedback mechanism between soil freeze/thaw and soil temperature/ground heat flux; (ii) during freezing period all three heat fluxes do not vary apparently, in spite of the fact that the negative soil temperature is higher than that not considering soil freeze; (iii) during thawing period, ground heat flux increases, and sensible heat flux decreases, but latent heat flux does not change much; and (iv) during freezing period, soil temperature decreases, though ground heat flux increases.

关键词： land surface model,soil freeze/thaw,GAME/Tibet,simultaneous liquid,vapor and heat transfer.

Estimation on the response of glaciers in china to the global warming in the 2.st century

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Chinese Science Bulletin 2000年第7期45卷 668-672页

作者： SHI Yafeng & LIU Shiyin Laboratory of Ice Core and Cold Regions Environment, Cold and Arid Regions Environmental and Engineering research institute, Chinese Academy of Sciences,{2., china Cold and Arid Regions Environmental and Engineering research institute, Chinese Academy of Sciences,{2., china Laboratory of Ice Core and Cold Regions Environment Cold and Arid Regions Environmental and Engineering Research Institute Chinese Academy of Sciences Lanzhou China Cold and Arid Regions Environmental and Engineering research institute Chinese Academy of Sciences Lanzhou China

Glaciers in china can be categorized into 3 types, i.e. the maritime (temperate) type, sub-continental (sub-polar) type and extreme Continental (polar) type, which take 2.%, 46% and 32. of the total existing glacier area (59 406 km2. respectively. researches indicate that glaciers of the three types show different response patterns to the global warming. Since the Maxima of the Little Ice Age (the 17th century), air temperature has risen at a magnitude of 1.3℃on average and the glacier area decreased corresponds to 2.% of the present total glacier area in western china. it is estimated that air temperature rise in the 2.30s, 2.70s and 2.00s will be of the order of 0.4-1.2. 1.2.2.7 and 2.1-4.0 K in western china. With these scenarios, glaciers in china will suffer from further shrinkage by 12., 2.% and 45% by the 2.30s, 2.70s and 2.00s. The uncertainties may account for 30%-67% in 2.00 in china.

关键词： modern glacier global warming Little Ice Age glacier type temperature rise in the 2.st century estimated glacier shrinkage.

Relationships between δ ^(18)O in summer precipitation and temperature and moisture trajectories at Muztagata, western china

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Science china Earth Sciences 2006年第1期49卷 27-35页

作者： YU Wusheng1,2. YAO Tandong1,2. TIAN Lide1,2. LI Zhen2. SUN Weizhen2.& WANG Yu2.1. Laboratory of Environment and Process on Tibetan Plateau, institute of Tibetan Plateau research, Chinese Academy of Sciences, Beijing 100085,{2. 2. Key Laboratory of Cryosphere and Environment, Jointly Established by Cold and Arid Regions Environmental and Engi-neering research institute and institute of Tibetan Plateau research, Chinese Academy of Sciences and Chinese Academy of Meteorological Sciences,{2. Meteorological Administration, CAS, lanzhou 73.000,{2. Laboratory of Environment and Process on Tibetan Plateau Institute of Tibetan Plateau Research Chinese Academy of Sciences Beijing China Key Laboratory of Cryosphere and Environment Jointly Established by Cold and Arid Regions Environmental and Engineering Research Institute and Institute of Tibetan Plateau Research Chinese Academy of Sciences and Chinese Academy of Meteorological Sciences China Meteorological Administration Lanzhou China

Based on summer observations of stable isotope of precipitation at Muztagata, western china, during 2.02.2.03, this paper presents the relationship between δ 18O in precipitation and air temperature, and discusses the effect of moisture transport on δ 18O in precipitation. Results show that air temperature correlates positively with δ 18O in precipitation, and the temperature effect controls the δ 18O of precipitation in this area. The Muztagata region exhibits high δ 18O values in summer precipi-tation, similar to those shown at stations in adjacent regions. According to the results of our model set up to trace the moisture trajectories, the westerlies and local moisture circulation contribute to varia-tions of oxygen isotopes in precipitation. In addition, the impacts of the moisture transport distance, the moisture transport level, and the incursion of the polar air mass also influence the variations of δ 18O in precipitation. The moisture origins and transport mechanisms also contribute to the variation of δ 18O in precipitation at Muztagata.

关键词： Muztagata, δ18O, precipitation, temperature, moisture transport.

Joint exploration of crustal structure in Fuzhou basin and its vicinities by deep seismic reflection and high-resolution refraction as well as wide-angle reflection/refraction

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Science china Earth Sciences 2005年第7期48卷 925-938页

作者： ZHU Jinfang1, XU Xiwei2. ZHANG Xiankang3, HUANG Zonglin1, CHEN Xiangxiong1, FANG Shengming3, LIU Baojin3, ZHENG Rongzhang2.4 1. Seismological Bureau of Fujian Province,Fuzhou 350003,china 2. institute of Geology,china earthquake Administration,Beijing 10002.,china 3. research Center for Exploration Geophysics,china earthquake Administration,Zhengzhou 450002.china 4. State Key Laboratory of earthquake Dynamics,institute of Geology,china earthquake Administration,Beijing 10002.,china Seismological Bureau of Fujian Province Fuzhou 350003 China institute of Geology China Earthquake Administration Beijing 100029 China research Center for Exploration Geophysics China Earthquake Administration Zhengzhou 450002 China State Key Laboratory of earthquake Dynamics Institute of Geology China Earthquake Administration Beijing 100029 China

The Fuzhou basin and its vicinities are located at the northern end of the southeastern coastal seismic zone of the mainland of china. By the joint explorations of high-resolution seismic refraction and wide-angle reflection/refraction as well as deep seismic reflection in the region, which is the first synthetic profile in china, its fine velocity structure and geometric structure from the ground to Moho discontinuity is obtained. The result shows that the crust is obviously layered with a thickness of about 32.km. Basically, it consists of two parts: upper crust and lower crust. The velocity of the upper crust is 5.9-6.2.km/s in which there is a 3-4-km-thick weak low-velocity layer between the depths of 10-15 km, while the velocity of the lower crust in the range of 6.3-7.2.km/s. There exists a strong velocity gradient layer about 3 km thick above the Moho discontinuity whose velocity increases from 6.5 to 7.2. km/s. There exist high-angle normal faults that are small in size and extend only in the shallow crust. These faults are the secondary developed on the hanging wall of westward dipping low-angle normal faults. Thus, their seismogenic ability is limited, however, there exists a high-angle deep fault in the crust from Changle-Zaoan fault zone to seashore fault zone. This deep fault has cut the interface between the upper and lower crusts and Moho discontinuity, and may be the deep structure to trigger destructive {2. source in future to affect Fuzhou City. These results have advanced the detecting precision of the deep structure in the southeastern coastal seismic zone of the mainland of china. In the aspect of the combined feature of the deep and shallow extensional structures that consist of the westward dipping low-angle normal faults and secondary normal faults on their hanging walls in the upper crust, it is firstly obtained that a united structural interpretation has deepened the knowledge about the deep dynamic process in the southeastern coasta

关键词： deep seismic reflection high-resolution seismic refraction wide-angle.

Ice core dust particulate by XPS-SEM/EDAX——Impact of dust particulate on SO_4^(2.) record in ice cores

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Chinese Science Bulletin 1999年第15期44卷 1424-1427页

作者： LI Zhongqin , LU Gongxuan , LIU Baozhong , FU Hongxiang LIU YuTianshan Glaciological Station , lanzhou institute of Glaciology and Geocryology , Chinese Academy of Sciences ,{2.,china State Key Laboratory for Oxo Synthesis and Selective Oxidation, lanzhou institute of Chemical Physics , Chinese Academy ofSciences ,{2., china, Tianshan Glaciological Station Lanzhou Inst. Glaciol. Geocryology Chinese Academy of Sciences Lanzhou 730000 China State Key Lab. Oxo Synthesis S. Lanzhou Inst. of Chemical Physics Chinese Academy of Sciences Lanzhou 730000 China

The ice core dust particulate sampled from Mt. Xixabangma has been analyzed by means of X-ray photoelectron spectrometer （XPS） and scanning electron microscope with energy dispersion X-ray analysis （SEM/EDAX）. The results show that the contents of SO42. and SO32. in the surface layer of the dust are significantly higher than those in the subsurface layer （with the exception of organic sulfide）. This difference indicates that the surface SOx has been captured and then chemically converted by the atmospheric dust particulate before its deposition with snow, which is obviously different from those inner layer sulfates and sulfites contained by dust itself. In addition, it has been determined by SEM/EDAX that the dust contains relatively high concentrations of transition metal elements such as Fe and Ti oxides which could function as photocatalysts to the conversion of SOx adhered on the surface of the dust, and consequently accelerate the deposition of SOx to snow. Our research also

关键词： ice core records dust partculate sulfate ions.

Progress and review of the studies on the end-Triassic mass extinction event

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Science china Earth Sciences 2005年第12期48卷 2049-2060页

作者： DENG Shenghui1,2. LU Yuanzheng1,2.3 & XU Daoyi4 1. research institute of Petroleum Exploration and Development, Beijing 100083,{2. 2. Key Laboratory of Oil and Gas Reservoir of Petrochina, Beijing 100083,{2. 3.{2. University of Geosciences, Beijing 100083,{2. 4. institute of Geology,{2. earthquake Administration, Beijing 10002.,{2. research institute of Petroleum Exploration and Development Beijing China Key Laboratory of Oil and Gas Reservoir of Petrochina Beijing China china University of Geosciences Beijing China institute of Geology China Earthquake Administration Beijing China

The mass extinction at the end-Triassic is one of the five biggest in the Phanerozoic. However,it is the least well understood among these five events, and only till last decade it became a great academic interesting subject to geologists. The evidences for this event come obviously from bivalves, brachiopods, ammonites, corals, radiolaria, ostracods and foraminifera of marine habitats, and plants and tetrapods of terrestrial realm. By contrast, for some of other groups, such as marine gastropods and marine vertebrates, no mass extinction has been recog-nized yet. The extinction event is strongly marked at specific level but shown a complicated situa-tion at generic and family levels. Dramatic changing of the environment, such as the temperature raise due to the greenhouse effect, the marine anoxic habitats caused by a sudden transgression after the regression at the end of Triassic, has been claimed to be the main cause of the extinction. Many hypotheses have been suggested to demonstrate the mechanisms of the environment changing, among which two popular ones are the bolide impact and volcanic eruption. The Triassic-Jurassic (Tr-J) boundary mass extinction event is still poorly understood because no enough data have been obtained from the Tr-J boundary successional sections of both marine and terrestrial sediments, and most of these studies were regionally restricted. The basic aspects of the event and its associated environmental conditions remain poorly characterized and the causal mechanism or mechanisms are equivocal. Some authors even doubt its occurrence. china has many successionally developed terrestrial and marine Tr-J sections. Detailed studies of these sections may be important and significant for well understanding of the event.

关键词： progress, review, end-Triassic, mass extinction, mechanism, Tr-J boundary.