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The role of aerial algae in the formation of the landscape of the Yunnan Stone Forest,Yunnan Province, china

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Science china Earth sciences 2004年第9期47卷 846-864页

作者： TIAN Youping1,3. ZHANG Jie2, SONG Linhua1 & BAO Haosheng2 1. Institute of Geographic sciences and Natural Resources Research, chinese Academy of sciences, {3. 100101, china 2. Department of Geography, Nanjing University, Nanjing 210093. china 3. school of Earth sciences and Resources, china University of Geosciences, {3. 100083. china Institute of Geographic sciences and Natural Resources Research Chinese Academy of Sciences Beijing 100101 China Department of Geography Nanjing University Nanjing 210093 China school of Earth sciences and Resources China University of Geosciences Beijing 100083 China

Aerial algae on the surface of carbonate rocks at the Stone Forest, Shilin County, Yunnan Province, china, and their bioerosion were investigated in the field and studied in the laboratory in detail. Through the observation, identification and statistics of more than one hun- dred algal samples and rock samples with the optical microscopes (stereomicroscope, biological microscope) and the scanning electronic microscope (SEM), the relationships between erosional forms on the surface of the Stone Forest and algae and/or algal communities and the genetic mechanism for the formation of erosional forms were analyzed. It is suggested that aerial algae play an active role in bioerosive processes that may affect the formation of karst erosional forms. These effects include both direct and indirect ones. The direct effect is the initiative control (algal shape-controlling role) of algae on the formation of karst forms of various scales, mostly mi- cro-scale (3.) and minor-scale (10-3.10-1m) erosional forms. The algal shape-controlling roles can be divided into the algal individual shape-controlling role and the algal community shape-controlling role. The former mostly controls the formation of micro-scale erosional forms, while the latter mostly controls the formation of micro-scale and smaller minor-scale erosional forms. The indirect effect refers to the promoting role of algae in the formation of karst forms, which may affect the formation of karst forms of all types and scales. The bioerosion of algae accelerates the weathering process of the whole Stone Forest karst landforms.

关键词： aerial algae, bioerosion, the Stone Forest, Yunnan Province, china.

Population information extraction in Chaohu watershed based on RS and GIS

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chinese Science Bulletin 2003年第2期48卷 181-183页

作者： LIU Jianjun1,2 & LI Chunlai3.1. Institute of Geochemistry, chinese Academy of sciences, Guiyang 550002, china 2. {3. school, chinese Academy of sciences, beijing 10003., china 3. National Astronomical Observatories, chinese Academy of sciences, beijing 100012, china Correspondence should be addressed to Liu Jianjun (e-mail: dhsliujj@ ***) Institute of Geochemistry Chinese Academy of Sciences Guiyang China graduate school Chinese Academy of Sciences Beijing China National Astronomical Observatories Chinese Academy of Sciences Beijing China

It is always difficult to extract population in-formation of small watershed during the region environment assessment. The report adopted compound areal interpola-tion to study the population in Chaohu watershed with the GIS technique and landuse interpretation data from remote sensing. The result indicated that the method is effective to extract population information of small watershed.

关键词：巢湖流域人口分布信息提取 RS GIS 小流域生态环境评价

An efficient chiral synthesis of (R)-N-[3.acetyl-4.(2-hydroxy-3.isopropylamino-propoxy)phenyl]-butanamide with high enantioselectivity

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Science china Chemistry 2009年第8期52卷 1216-1219页

作者： WANG NaiXing1,2 & TANG XinLiang1,3.1 Technical Institute of Physics and Chemistry,chinese Academy of sciences,beijing 100080,{3. 2 College of Chemistry and Chemical Engineering,graduate University of chinese Academy of sciences,beijing 10004.,{3. 3.school of Chemical Engineering and Environment,beijing Institute of Technology,beijing 100081,{3. 1. Technical Institute of Physics and Chemistry Chinese Academy of Sciences Beijing 100080 China 2. College of Chemistry and Chemical Engineering Graduate University of Chinese Academy of Sciences Beijing 100049 China 3. school of Chemical Engineering and Environment Beijing Institute of Technology Beijing 100081 China

R-Enantiomer of the β-receptor antagonist N-[3.acetyl-4.(2-hydroxy-3.isopropylamino-propoxy)phenyl] butanamide with high enantioselectivity was synthesized from cheap starting materials and enantiopure chiral reagent through an efficient,convenient and practical synthetic *** product was detected by 1H NMR,13. NMR,and MS,and the enatiomeric excess was determined by chiral HPLC analysis using a chiracel AD-H column.

关键词： chiral synthesis enantioselectivity enatiomeric excess chiral HPLC analysis

Threshold quantum secure direct communication without entanglement

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Science china(Physics,Mechanics & Astronomy) 2008年第2期51卷 176-183页

作者： YANG YuGuang1,3.& WEN QiaoYan2 1 College of Computer Science and Technology, beijing University of Technology, beijing 100022, china 2 {3. of Science, beijing University of Posts and Telecommunications, beijing 100876, china 3.State Key Laboratory of Information Security (graduate {3. of chinese Academy of sciences), beijing 10004., china 1. College of Computer Science and Technology Beijing University of Technology Beijing 100022 China 3. State Key Laboratory of Information Security (graduate school of chinese Academy of {3.) Beijing 100049 China 2. school of Science Beijing University of Posts and Telecommunications Beijing 100876 China

For the first time, a threshold quantum secure direct communication (TQSDC) scheme is presented. Similar to the classical Shamir's secret sharing scheme, the sender makes n shares, S1, …, Sn of secret key K and each receiver keeps a share secretly. If the sender wants to send a secret message M to the receivers, he en-codes the information of K and M on a single photon sequence and sends it to one of the receivers. According to the secret shares, the t receivers sequentially per-form the corresponding unitary operations on the single photon sequence and ob-tain the secret message M. The shared shares may be reusable if it can be judged that there is no eavesdropper in line. We discuss that our protocol is feasible with current technology.

关键词： quantum secure direct communication threshold secure direct communication quantum secret sharing

Inertial theory of the mean Hadley circulation under the condition of nonstatic equilibrium

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Science china Earth sciences 2006年第5期49卷 546-553页

作者： CHAO Jiping1 & LIU Fei2,3.1. National Marine Environmental Forecasting Center, beijing 100081, china 2. Key Laboratory Regional Climate-Environment for Temperate East Asia, Institute of Atmospheric Physics, chinese Academy of {3., beijing 100029, china 3. graduate University of chinese Academy of {3., beijing 10004., china 1. National Marine Environmental Forecasting Center Beijing 100081 China 2. Key Laboratory Regional Climate-Environment for Temperate East Asia Institute of Atmospheric Physics Chinese Academy of Sciences Beijing 100029 China 3. graduate University of chinese Academy of sciences Beijing 100049 China

Tropical atmosphere is divided into two layers, the layer near the ground is the planet boundary layer, where the motion is linear, if the radiation equilibrium temperature is given at the top of the boundary layer, the vertical motion there can be obtained. It is the non-viscous ideal atmos- pheric layer above the boundary one, where the motion is nonlinear. After getting the conservation laws of angular momentum, potential temperature and potential vortex, the inertial theory of the Hadley circulation driven by the vertical motion of the boundary layer is established, followed by sev- eral examples of its application.

关键词： Hadley circulation, inertial theory, conservation laws of angular momentum, potential temperature and potential vortex.

Experimental study on phosphorus release from sediments of shallow lake in wave flume

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Science china Earth sciences 2006年第z1期49卷 92-101页

作者： SUN Xiaojing,ZHU Guangwei, LUO Liancong & QIN Boqiang Nanjing Institute of Geography & Limnology, chinese Academy of sciences, Nanjing 210008, china {3. {4. of chinese Academy of sciences, beijing 10003., china 1. Nanjing Institute of Geography & Limnology Chinese Academy of Sciences Nanjing 210008 China2. Graduate School of Chinese Academy of Sciences Beijing 100039 China

Influence of wave on sediment resuspension and nutrients release from sediments, collected from Lake Taihu and Lake Chaohu, was studied in flume experiments. Under strong-wave conditions, concentrations of suspended solids (SS), total phosphorus (TP) and dissolved total phosphorus (DTP) in overlying water were increased significantly following the sediments re-suspension. During the experiments on sediments of Lake Taihu and Lake Chaohu, TP concentrations increased 6 times and 3.times, and DTP concentration increased 100% and 70% more than it in presuspension, respectively. Concentration of soluble reactive phosphorus (SRP) of experiment on sediment of Lake Taihu increased 25%. During the massive sediment suspension, the dissolved phosphorus in pore water and much of the phosphorus adsorbed by the sediment particles were released into overlying water. The phenomena in this wave flume experiment are quite similar to the situation observed in situ of Lake Taihu. The critical wave stresses of sediment re-suspension are nearly equal. The change of concentrations of SS, TP, and SRP was the same as that in situ *** study showed that concentrations of TP and SRP in lake water could be increased significantly by wave disturbance. Phosphorus release was significantly enhanced by wave disturbance at the beginning of massive sediment re-suspension, but decreased later.

关键词： shallow lakes, wave disturbance, internal release, phosphorus, wave flume experiment.

Genetic fingerprinting of plankton community provides new insights into aquatic ecology

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Progress in Natural Science:Materials International 2006年第9期16卷 893-898页

作者： YAN Qingyun, YU Yuhe and FENG Weisong ( Institute of Hydrobiology, chinese Academy of sciences, Wuhan 4.2}072, china {3. school of the chinese Academy of Sci-ences, beijing 10003., china) [a]Institute of Hydrobiology Chinese Academy of Sciences Wuhan China [b]graduate school of the chinese Academy of {3. Bejing China

Over the past two decades, molecular techniques have been widely used in ecological study and molecular ecology has been one of the most important branches of ecology. Meanwhile, genetic fingerprinting analyses have significantly enhanced our knowledge of the diversity and evolutionary relations of the planktonic organisms. Compared with conventional approaches in ecological study (e.g. morphological classification), genetic fingerprinting techniques are simpler and much more effective. This review provides an overview of the principles, advantages and limitations of the commonly used DNA fingerprinting techniques in plankton research. The aim of this overview is to assess where we have been, where we are now and what the future holds for solving aquatic ecological problems with molecular-level information.

关键词： genetic fingerprinting plankton community aquatic ecology genetic diversity.

Response of remotely sensed Normalized Difference Water Deviation Index to the 2006 Drought of eastern Sichuan Basin

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Science china Earth sciences 2008年第5期51卷 748-758页

作者： ZHANG WenJiang1, LU QiFeng2, GAO ZhiQiang3.& PENG Jian4.1 school of Water Resource and Hydropower, Sichuan University, Chengdu 610065, china 2 National Satellite Meteorological Center, china Meteorological Administration, {3. 100081, china 3.Institute of Geographic sciences and Natural Resources Research, chinese Academy of sciences, {3. 100101, china 4.school of Environmental sciences, Peking University, {3. 100871, china 1. school of Water Resource and Hydropower Sichuan University Chengdu 610065 China 2. National Statellite Meteorological Center China Meteorological Administration Beijing 100081 China 3. Institute of Geographic sciences and Natural Resources Research Chinese Academy of Sciences Beijing 100101 China 4. school of Environmental sciences Peking University Beijing 100871 China

One of the most serious droughts in last century occurred in eastern Sichuan Basin in the summer of 2006 (hereinafter called the Drought). The response of Moderate Resolution Imaging Spectroradiometer (MODIS, boarding on NASA satellites of Terra and Aqua) to the Drought was analyzed in order to reach one practicable monitoring solution for regional soil moisture. Temporal process and spatial extension of the Drought were firstly estimated with ground meteorological and hydrological observations. Then, for the whole region of Sichuan and Chongqing, the remotely sensed Normalized Difference Water In- dex (NDWI) for the summers of 2001―2006 were calculated based on 8-day composite MODIS products, which were further used to construct a new water index (Normalized Difference Water Deviation Index, NDWDI) to examine the sensitivity of remote sensing in the Drought. The study showed that the NDWDI is more sensitive to regional drought than other absolute-soil-moisture-based indices. With the new index, the study extracted the spatial-temporal characteristics of the 2006 Drought, and explored its developing and withdrawing processes, which agreed with related statistics. Compared with ground method of drought observation, the NDWDI-based remote sensing solution of this paper is more pref- erable and practicable in that the local soil properties of water consumption and supply are implicitly taken into account, and the spatial representativity limit of ground observation is circumvented to a degree as satellite remotely senses the earth surface in a way of two-dimensional pixel matrix. So, the NDWDI-based method can be used to monitor regional soil water stress situation more practically and efficiently.

关键词： Sichuan Basin drought Normalized Difference Water Deviation Index response of remote sensing regional scale

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 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 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.