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Evolution of desertification in a two-dimensional energy balance model coupled with thermodynamics and dynamics

Science china Earth Sciences 2010年第11期53卷 1726-1733页

作者： CHAO JiPing1,2 & LI YaoKun3,4.1National Marine Environmental Forecasting Center, Beijing 100081, china 2First Institute of Oceanography, State Oceanic administration, Qingdao 266061, china 3State Key Laboratory of Numerical Modeling for Atmospheric Sciences and Geophysical Fluid Dynamics, Institute of Atmospheric Physics, Chinese Academy of Sciences, Beijing 100029, china 4.raduate University of Chinese Academy of Sciences, Beijing 10004., china 1. National Marine Environmental Forecasting Center Beijing 100081 China2. First Institute of Oceanography State Oceanic Administration Qingdao 266061 China3. State Key Laboratory of Numerical Modeling for Atmospheric Sciences and Geophysical Fluid Dynamics Institute of Atmospheric Physics Chinese Academy of Sciences Beijing 100029 China4. Graduate University of Chinese Academy of Sciences Beijing 100049 China

The relationship between desert evolution and change in albedo has been investigated quasi-analytically using a zonal mean two-dimensional energy balance model which considers the radiation transmission process due to thermodynamics and bound- ary layer movement caused by kinetics. A climate state including temperature, zonal wind, meridional wind and vertical wind can be simulated according to the current zonal distribution of albedo. Given desert distribution, characterized by the value and distribution of albedo, the response of climate on albedo has been studied to analyze the evolution of desert climate. One significant result is that the simple model can reproduce mean meridional circulation. Another result indicates that climate corresponds to two equilibria. This happens when the junction temperature between vegetation and desert is higher than a certain critical value. As for the first equilibrium, the desert belt is predicted to move southward in the northern hemisphere with the increasing values of albedo, which corresponds to the current trend of climate change. For the second equilibrium, vegetation will expand northward with increasing values of albedo, which would indicate a narrowing of the desert belt. In order to determine if the two equilibria exist, new physical models are needed.

关键词： two-dimensional energy balance model desertification two equilibria

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Analytical method of Cr stable isotope and its application to water pollution survey

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Chinese Science Bulletin 2010年第7期55卷 664-669页

High Cr(VI) concentration is a potential serious risk to environment and ecologic ***,it is essential to effectively monitor Cr contamination in water systems and scientifically evaluate its evolution trend.A new method of in-situ tracer technique by Cr isotopic analysis for quantitatively estimating Cr-contamination and its regional evolution in natural waters as well as a case application are reported in this *** on documented literatures,an experimental procedure for chemical separation and purification of Cr in water samples and its analytical method for Cr isotopic measurement by thermal ionization mass spectrometry(TIMS) are *** samples collected around a chemical factory in Hubei province were analyzed by this *** samples showδ53Cr values ranging from-1.7‰to 7.3‰and an elevating trend with an increasing in distance from the sampling site to pollution source.A functional correlation following Rayleigh fractionation law was established between sample'sδ53Cr value and its extent of Cr *** study suggests that Cr isotopic analysis is an effective method to reveal the spatial distribution and its evolution trend of Cr contamination in the regional water *** is thus helpful to assessing the self-purifying ability of local water system according to Cr isotopic fractionation.

关键词：铬(VI) 水污染调查稳定同位素应用同位素分析供水系统演变趋势示踪技术

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LOD score exclusion analyses for candidate disease susceptibility genes using case-parents design

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Progress in Natural Science:Materials International 2006年第1期16卷 30-38页

作者： DENG Hongwen1,2,3 and GAO Guimin2,4.(1.Laboratory of Molecular and Statistical Genetics, College of Life Sciences, Hunan Normal University, Changsha 4.0081, china 2.Osteoporosis Research Center, Creighton University Medical Center, Omaha NE 68131, USA 3. Department of Biomedical Sciences, Creighton University, Omaha NE 68131, USA 4. Virginia Bioin format ics Institute and Department of Statistics, Virginia Polytechnic Institute and State University, Blacksburg VA 24.61-0315, USA) [a]Laboratory of Molecular and Statistical Genetics College of Life Sciences Human National University Changsha China [b]Osteoporosis Research Center Creighton University Medical Center Omaha NE USA [c]Department of Biomedical Sciences Creighton University Omaha NE USA [d]Virginia Bioinformatics Institute and Department of Statistics Virginia Polytechnic Institute and State University Blacksburg VA USA

The focus of almost all the association studies of candidate genes is to test for their importance. We recently developed a LOD score approach that can be used to test against the importance of candidate genes for complex diseases and quantitative traits in random samples. As a complementary method to regular association analyses, our LOD score approach is powerful but still affected by the population admixture, though it is more conservative. To control the confounding effect of population heterogeneity, we develop here a LOD score exclusion analysis using case-parents design, the basic design of the transmission disequilibrium test (TDT) approach that is immune to population admixture. In the analysis, specific genetic effects and inheritance models at candidate genes can be analyzed and if a LOD score is ≤ - 2. 0, the locus can be excluded from having an effect larger than that specified. Simulations show that this approach has reasonable power to exclude a candidate gene having small genetic effects if it is not a disease susceptibility locus (DSL) with sample size often employed in TDT studies. Similar to association analyses with the TDT in nuclear families, our exclusion analyses are generally not affected by population admixture. The exclusion analyses may be implemented to rule out candidate genes with no or minor genetic effects as supplemental analyses for the TDT. The utility of the approach is illustrated with an application to test the importance of vitamin D receptor (VDR) gene underlying the differential risk to osteoporosis.

关键词： association studies candidate genes case-parents design disease susceptibility locus exclusion mapping LOD score.

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Spatial prediction and analysis of Himalayan marmot plague natural epidemic foci in china based on HJ-1 satellite data

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Science china Earth Sciences 2010年第S1期53卷 8-15页

作者： GAO MengXu1,4.LI XiaoWen1,2,CAO ChunXiang1,ZHANG Hao1,LI Qun3,ZHOU Hang3 HE QiSheng1,4.XU Min1,4.ZHAO Jian1,4.ZHENG Sheng1,4.& CHEN Wei1,4.1State Key Laboratory of Remote Sensing Science,Jointly Sponsored by the Institute of Remote Sensing Applications of Chinese Academy of Sciences and Beijing Normal University,Beijing 100101,china 2School of Geography,Beijing Normal University,Beijing 100875,china 3Office for Disease Control and Emergency Response,Chinese Center for Disease Control and Prevention,Beijing 102206,china 4.raduate University of Chinese Academy of Sciences,Beijing 10004.,china 1. State Key Laboratory of Remote Sensing Science Jointly Sponsored by the Institute of Remote Sensing Applications of Chinese Academy of Sciences and Beijing Normal University Beijing 100101 China4. Graduate University of Chinese Academy of Sciences Beijing 100049 China2. School of Geography Beijing Normal University Beijing 100875 China3. Office for Disease Control and Emergency Response Chinese Center for Disease Control and Prevention Beijing 102206 China

Plague,caused by the gram-negative bacterium Yersinia pestis,is a serious and rapidly progressing illness in humans that can be fatal if not treated *** Qinghai-Tibet Plateau is the largest area of natural Himalayan marmot(Marmota himalayana) plague foci in china and covers more than 630000 *** County in Gansu province is a part of this natural focus of plague and was chosen as a study *** study used an ecological niche modeling(ENM) approach to predict the potential distribution of the Himalayan *** and Disaster Monitor Satellite(HJ-1) data was used to investigate environment factors that affect plague host animal *** animal point data from active surveillance was combined with environmental variables from the HJ-1 satellite and other databases,and the models of the potential distribution of Himalayan marmot were produced with the Genetic Algorithm for Rule-Set Production(GARP).The probability of marmot presence was divided into 0-5%,5%-20%,20%-4.%,4.%-80%,and 80%-100% *** with 80%-100% probability exhibited the greatest potential for the presence of Himalayan *** to the predicted potential distribution of Himalayan marmot in the study area,active surveillance of plague hosts and plague control and prevention could be more efficient.

关键词： Himalayan marmot plague spatial prediction GARP HJ-1 satellite

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Growth characteristics and response to climate change of Larix Miller tree-ring in china

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Science china Earth Sciences 2010年第6期53卷 871-879页

作者： SUN Yu1,4. WANG LiLi1,2,3, CHEN Jin5, DUAN JianPing1,4. SHAO XueMei1,2 & CHEN KeLong6 1 Institute of Geographic Sciences and Natural Resources Research, Chinese Academy of Sciences, Beijing 100101, china 2 Institute of Tibetan Plateau Research, Chinese Academy of Sciences, Beijing 100085, china 3 Institute of Desert and Meteorology, china Meteorological administration, Urumqi 830002, china 4.Graduate University of Chinese Academy of Sciences, Beijing 10004., china 5 Institute of Vertebrate Paleontology and Paleoanthropology, Chinese Academy of Sciences, Beijing 10004., china 6 School of Life and Geography Sciences, Qinghai Normal University, Xining 810008, china 1. Institute of Geographic Sciences and Natural Resources Research Chinese Academy of Sciences Beijing 100101 China4. Graduate University of Chinese Academy of Sciences Beijing 100049 China2. Institute of Tibetan Plateau Research Chinese Academy of Sciences Beijing 100085 China3. Institute of Desert and Meteorology China Meteorological Administration Urumqi 830002 China5. Institute of Vertebrate Paleontology and Paleoanthropology Chinese Academy of Sciences Beijing 100044 China6. School of Life and Geography Sciences Qinghai Normal University Xining 810008 China

As one of the earliest species used in dendrochronological studies, Larix responds sensitively to climate change. In this study, nine larch species and one variety from eleven sites were collected to study the growth characteristics of tree-ring width using dendrochronological methods. Ten residual tree-ring chronologies were developed to analyze their relationships with regional standardized anomaly series by Pearson’s correlation analysis. The results suggest that most of the chronologies had significantly positive correlations with the mean temperature and mean maximum temperature in May. The spring temperature evidently limited the radial growth of the larch species without precipitation control. The largest mean tree-ring width was found in Himalayan Larch in Jilong, whereas Master Larch in Si’er reflected the smallest mean value. Both species presented little climate information in this study. Chinese, Potanin, and Tibetan larches are significantly correlated with climate change, implying a huge potential for climate history reconstruction. The elevation of the sampling sites appears to be an important condition for tree-ring growth of larches responding to climate factors.

关键词： Larix Miller tree-ring climate change mean temperature in May

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The potential effect of variations in climate and agricultural practice on N_2O emissions (Ⅱ)——Variations in agricultural practice

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Chinese Science Bulletin 1999年第S2期44卷 97-99页

作者： XU Wenbin~(1,2), HONG Yetang~1, CHEN Xuhui~3, LI Changsheng~4. LIN Qinghua~1 and WANG Yu~1, 1. State Key Laboratory of Environmental Geochemistry, Institute of Geochemistry, Chinese Academy of Sciences, Guiyang 550002, china 2. Institute of Environment and Resources Chemistry, Zhejiang University, Hangzhou 310027, china 3. Soil and Fertilizer Institute, Guizhou Academy of Agricultural Sciences, Guiyang 550013, china 4. Institute for the Study of Earth, Oceans, and Space, University of New Hampshire, Durham, USA State Key Laboratory of Environmental Geochemistry Institute of Geochemistry Chinese Academy of Sciences Guiyang 550002 China Institute of Environment and Resources Chemistry Zhejiang University Hangzhou 310027 China Soil and Fertilizer Institute Guizhou Academy of Agricultural Sciences Guiyang 550013 China Institute for the Study of Earth Oceans and Space University of New Hampshire Durham NH United States

WE expanded Decomposition-Denitrification （DNDC）modeling study to systematically assess the potential effect of farming practice on N2O emission by choosing a corn-rape rotation and a soybean-winterwheat rotation field in Guizhou province, westsouthern china, asN2O emission from subtropical agricultural soil study plots. These sensitivity studies address questions relevant to issue of how change in fanning practice might be used to mitigate emissions. Manure additions had the most pronounced impact on N2O emissions of farming practice simulatedand the influence of manure addition was nonlinear （fig. 1）. This result is consistent with previous studies for an Iowa corn field. The addition of manure remarkably elevates the level of organic carbon, enhances soil nitrogen mineralization, and increases the efficiency of N2O production. Simulated results alsoshowed that the influence of manure additions on N2O emission from soybean-winter wheat field had

关键词： N2O emission farming practice potential effect agricultural soil.

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Sm-Nd isotopic ages of Tiqiushan eclogites in Xinyi region and its geological significance

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Chinese Science Bulletin 1999年第S2期44卷 144-146页

作者： WANG Yinxi~(1,2), YANG Jiedong~(1,2), TAO Xiancong~(1,2), GE Ningjie~4. CHEN Peirong~3, FAN Chunfang~3 and LI Jianhua~5 1. Center of Modern Analysis, Nanjing University, Nanjing 210093, china 2. State Key Laboratory for Research of Mineral Deposits, Nanjing University, Nanjing 210093, china 3. Department of Earth Science, Nanjing University, Nanjing 210093, china 4. Department of Earth and Space Sciences, University of Science and Technology of Chian, Hefei 230026, china 5. No.5 Geological Party of Jiangsu {4., Xuzhou 221005, china Center of Modern Analysis Nanjing University Nanjing 210093 China State Key Laboratory for Research of Mineral Deposits Nanjing University Nanjing 210093 China Department of Earth and Space Sciences University of Science and Technology of Chian Hefei 230026 China Department of Earth Science Nanjing University Nanjing 210093 China No. 5 Geological Party of Jiangsu province Xuzhou 221005 China

GEOLOGICAL scientists have paid much attention to the suture zones formed by collision between the Sino-Korean and Yangtze blocks because of the discovery of the ultrahigh pressue metamorphic (UHPM) rocksfrom northern Jiangsu province (Su), southern Shandong province (Lu) and the Dabie *** the age of 200-24. Ma is probably the best estimation for UHPM metamorphism in the DabieMountains, the primary intrusive and metamorphic ages of the complex from northern Jiangsu provincehave not been determined before. Using the Sm-Nd isotopic dating method, our study is aimed at datingthe UHPM metanorphic event of northern Jiangsu province and researching a probable relation between theUHPM rocks from the Dabie Mountains and the UHPM rocks from northern Jiangsu province.

关键词： northern Jiangsu eclogite rocks Sm-Nd isotopic ages.

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Comprehensive benefit of flood resources utilization through dynamic successive fuzzy evaluation model: A case study

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中国科学：技术科学英文版 2010年第2期53卷 529-538页

作者： FENG Feng1,2, XU ShiGuo1, LIU JianWei1, LIU Dan1,3 & WU Bo4.1 Institute of Water Environment, School of Civil and Hydraulic Engineering, Dalian University of Technology, Dalian 116024. china 2 Yellow River Conservancy Technical Institute, Kaifeng 4.5003, china 3 College of Water Resources, Shenyang Agricultural University, Shenyang 110161, china 4.Office of Flood Control and Draught Relief in Jilin province, Changchun 130033, china 1. Institute of Water Environment School of Civil and Hydraulic Engineering Dalian University of Technology Dalian 116024 China2. Yellow River Conservancy Technical Institute Kaifeng 475003 China3. College of Water Resources Shenyang Agricultural University Shenyang 110161 China4. Office of Flood Control and Draught Relief in Jilin Province Changchun 130033 China

Taking the flood resources utilization in Baicheng, Jilin during 2002–2007 as the research background, and based on the entropy weight and multi-level & multi-objective fuzzy optimization theory, this research established a multi-level & semi-constructive index system and dynamic successive evaluation model for comprehensive benefit evaluation of regional flood resources utilization. With the year 2002 as the base year, the analyzing results showed that there existed a close positive correlation between flood utilization volume and its benefits, comprehensive evaluation value and its comparison increment. Within the six successive evaluation years, the comprehensive benefit of 2003 was the best, in which the benefit evaluation increment reached 82.8% whereas the year of 2004.was the worst, in which the increment was only 18.2%. Thus the sustainability and correctness of the evaluation were verified by six years successive evaluation and increment comparison. The analyzing results showed that the economic benefits, ecological benefits and social benefits of flood utilization were remarkable, and that the comprehensive benefit could be improved by increasing flood utilization capacity, which would promote the regional sustainable development as well. The established dynamic successive evaluation provides a stable theoretical basis and technical support for further flood utilization.

关键词： flood resources utilization comprehensive benefit dynamic successive fuzzy evaluation Baicheng City

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Vortex genesis over the Bay of Bengal in spring and its role in the onset of the Asian Summer Monsoon

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Science china Earth Sciences 2011年第1期54卷 1-9页

作者： WU GuoXiong1, GUAN Yue1,2, WANG TongMei3, LIU YiMin1, YAN JingHui4.& MAO JiangYu1 1 State Key Laboratory of Numerical Modeling for Atmospheric Sciences and Geophysical Fluid Dynamics (LASG), Institute of Atmospheric Physics, Chinese Academy of Sciences, Beijing 100029, china 2Graduate University of Chinese Academy of Sciences, Beijing 10004., china 3Department of Atmospheric Science, Sun Yat-Sen University, Guangzhou 510275, china 4.ational Climate Center, china Meteorological {4., Beijing 100080, china 1. State Key Laboratory of Numerical Modeling for Atmospheric Sciences and Geophysical Fluid Dynamics (LASG) Institute of Atmospheric Physics Chinese Academy of Sciences Beijing 100029 China2. Graduate University of Chinese Academy of Sciences Beijing 100049 China3. Department of Atmospheric Science Sun Yat-Sen University Guangzhou 510275 China4. National Climate Center China Meteorological Administration Beijing 100080 China

Physical processes associated with onset of the 1998 Asian summer monsoon were examined in detail using multi-source datasets. We demonstrated that strong ocean-atmosphere-land interaction in the northern Indian Ocean and tropical Asian area during spring is a fundamental factor that induces the genesis and development of a monsoon onset vortex over the Bay of Bengal (BOB), with the vortex in turn triggering onset of the Asian summer monsoon. In spring, strong surface sensible heating over India and the Indochina Peninsula is transferred to the atmosphere, forming prominent in situ cyclonic circulation, with anticyclonic circulations over the Arabian Sea and northern BOB where the ocean receives abundant solar radiation. The corresponding surface winds along the North Indian Ocean coastal areas cause the ocean to produce the in situ offshore currents and upwelling, resulting in sea surface temperature (SST) cooling. With precipitation on the Indochina Peninsula increasing from late April to early May, the offshore current disappears in the eastern BOB or develops into an onshore current, leading to SST increasing. A southwest-northeast oriented spring BOB warm pool with SST >31°C forms in a band from the southeastern Arabian Sea to the eastern BOB. In early May, the Somali cross-equatorial flow forms due to the meridional SST gradient between the two hemispheres, and surface sensible heat over the African land surface. The Somali flow overlaps in phase with the anticyclone over the northern Arabian Sea in the course of its inertial fluctuation along the equator. The convergent cold northerlies on the eastern side of the anticyclone cause the westerly in the inertial trough to increase rapidly, so that enhanced sensible heat is released from the sea surface into the atmosphere. The cyclonic vorticity forced by such sensible heating is superimposed on the inertial trough, leading to its further increase in vorticity strength. Since atmospheric inertial motion is destr

关键词： air-sea interaction spring BOB warm pool monsoon onset vortex inertial oscillation Asian summer monsoon onset

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Preparation and microstructure of CuO-CoO-MnO/SiO2 nanocomposite aerogels and xerogels as catalyst carriers

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Progress in Natural Science:Materials International 2011年第4期21卷 330-335页

作者： Yue-qing ZHAO~1,Ying-hua LIANG~2,Xi-zhe ZHAO~3,Qian-yi JIA~4.Hong-sheng LI~4.1.College of Light Industry,Hebei United University,Tangshan 063000,china 2.College of Chemical Engineering,Hebei United University,Tangshan 063009,china 3.College of Printing and Packaging Engineering,Beijing Institute of Graphic Communication,Beijing 102600,china 4.College of Materials Science and Engineering,Hebei United University,Tangshan 063009,china [a] College of Light Industry Hebei United University Tangshan 063000 China [b] College of Chemical Engineering Hebei United University Tangshan 063009 China [c] College of Printing and Packaging Engineering Beijing Institute of Graphic Communication Beijing 102600 China [d] College of Materials Science and Engineering Hebei United University Tangshan 063009 China

CuO-CoO-MnO/SiO2nanocomposite aerogels and xerogels were prepared using tetraethyl orthosilicate（TEOS） as Si source,and aqueous solution of Cu,Co and Mn acetates as the precursor via sol-gel process,CO2supercritical drying（SCD） technique or ambient pressure drying *** microstructure of the CuO-CoO-MnO/SiO2nanocomposite aerogels and xerogels were characterized by field emission scanning electron microscopy（FE-SEM）,transmission electron microscopy（TEM） and X-ray diffraction（XRD）.The specific surface area,pore size and pore size distribution of the nanocomposite aerogels and xerogels were determined by the Brunauer-Emmett-Teller（BET） *** results showed that CuO-CoO-MnO/SiO2nanocomposite aerogels are porous,with a pore size distribution of 2-50 nm,an average pore size of 19.4.nm,a specific surface area of 384.9 m2/g and a particle size distribution of 10-150 nm,whereas the pore size distribution of CuO-CoO-MnO/SiO2composite xerogels is 1.7-128.6 nm,the average pore size is only 9.9 nm,the specific surface area is only 99.1 m2/g,and the particle size distribution is 100-500 *** structure of CuO-CoO-MnO/SiO2nanocomposite aerogels is favorable to increase the loading of catalysts.

关键词： composite aerogel composite xerogel catalyst carrier preparation microstructure

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