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Resource and Environmental Quality Changes and Adjustment Principles for Sustainable Development in Rapidly Developing Coastal Region of Southeastern china

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Pedosphere 2001年第4期11卷 289-299页

作者： ZHAO QIGUO institute of soil science, the{3., P. O. Box 821, nanjing 2.0008 (china) 中科院南京土壤所江苏南京 210008

Problems in water-land resources and environmental quality increase with the fast economic development in the coastal region of southeastern china. This region has the highest density in population, industry and towns in china, and the large export-oriented economy makes itself a strategic importance while china enters into international markets. The problems facing to this region include arable land reduction, land degradation aggravation, high percentage of built-up land with high rate of expansion, expanded non-point pollution, deteriorated water quality, decreasing biodiversity, destroyed ecosystems, severe air pollution, frequently occurred acid rain, and multi-pollutants. The important research fields in the near future should include a) influence of high-intensity exploitation of resources on changes of environment quality and its feedback; b) interface processes, key mechanisms and adjustment principles for degradation of water-, land-, and air-resources and environmental quality; c) evolvement processes and nurturing theory of biodiversity and ecological resources; and d) spatio-temporal variation and human-induced effects on regional resources and environment quality. Strategies for sustainable development in the region are as follows: a) controlling to ensure basic cultivated land area; b) enforcing remediation of polluted water environment, and controlling non-point pollution; c) strengthening ecological construction and ecological security; and d) controlling multi-pollution and preventing trace toxic pollutants.

关键词： coastal region environment quality fast economic development southeastern china water- land resource

Environmental characteristics of Mid-Holocene recorded by lacustrine sediments from Lake Daihai, north environment sensitive zone, china

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science china Earth sciences 2006年第9期49卷 968-981页

作者： SUN Qianli1,2, ZHOU Jie1, SHEN Ji3. CHEN Peng1,2, WU Feng1,2 & XIE Xiuping1,2 1. State Key Lab of Loess and Quaternary Geology, institute of Earth Environment, chinese academy of sciences, Xi’an 710075, china 2. Graduate University of chinese academy of sciences, Beijing 10003., china 3. nanjing institute of Geography and Limnology, chinese academy of sciences, nanjing 2.0008, china 1. State Key Lab of Loess and Quaternary Geology Institute of Earth Environment Chinese Academy of Sciences Xi’an 710075 China 2. Graduate University of chinese academy of sciences Beijing 100039 China 3. nanjing institute of Geography and Limnology Chinese Academy of Sciences Nanjing 210008 China

Climate proxies, such as total organic carbon and nitrogen (TOC, TN), carbonate content (CaCO3., grain-size and pollen of the sediment core retrieved from enclosed Lake Daihai which lies in the north china environment sensitive zone are analyzed to reconstruct the environment evolution of the area based on high-resolution radiocarbon chronology. The results reveal that the TOC and TN contents of the sediments correlate well with pollen percentage and pollen flux variations during the Holocene, and both reach their peak values simultaneously at 6.7―3.5 ka BP (calendar age, 7.6―3.6 ka BP). Since 6.7 ka BP, both the CaCO3.and organic matter contents of the core have simultaneous variations, and their high values also occur during 6.7―3.5 ka BP. While during 9.0―6.7 ka BP (calendar age, 10―7.6 ka BP) relatively lower level of organic matter content and pollen flux corre- spond to the higher level of carbonate content. The above relations suggest that during 6.7―3.5 ka BP, the productivity and effective precipitation were greatly improved in the lake drainage area, and this would probably strengthen the hydrodynamic conditions, enhancing organic matter, pollen and carbonate inputs from terrestrial sources. Such processes would account for the enrichment of both organic matter and carbonate in the sediments. While during 9.0―6.7 ka BP, the lower level of or- ganic matter, pollen flux but high carbonate content show depressed productivity and declined vege- tation coverage. The higher carbonate content at this stage would have probably resulted from the higher evaporation ratio of the lake water under relatively drier climate conditions. Therefore, it is in- ferred that during 6.7―3.5 ka BP, the climate was more humid with abundant rainfalls and vegetation was more flourishing in the Lake Daihai area. This can be seen as Holocene Climate Optimum (HCO). As a result, this has evident discrepancies with the traditional notion that the HCO occurs at Early Holocene or early Mid

关键词： Lake Daihai, Mid-Holocene, lacustrine sediments, environmental characteristics.

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,{3., 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 14C, 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 14C 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 14C dating is stronger. Based on the analysis on results of 14C, 210Pb and 13.Cs of the lacustrine sediments from Co Ngoin, central Tibetan Plateau, we use the simple regression method to re-calculate the 14C 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 14C calendar age for sediments bellow 3. cm. Since 1400 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： 14C, 210Pb and 13.Cs, chronology, lacustrine sediments, climatic event, Co Ngoin, central Tibetan Plateau.

PROBABILISTIC NUMERICAL APPROACH FOR PDE AND ITS APPLICATION IN THE VALUATION OF EUROPEAN OPTIONS

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Journal of Computational Mathematics 2001年第6期19卷 591-600页

作者： Dong-sheng Wu (institute of Systems science, academy of Mathematics and Systems {3., chinese academy of sciences, Beijing 100080, china ) 中科院系统科学所北京 100080

Presents a probabilistic numerical approach for a class of probabilistic differential equation. Application of the Brownian motion and Monte-Carlo method; Application in the valuation of European Options.

关键词： Brownian motion probabilistic numerical solution European Options

Physical mechanisms of plant roots affecting weathering and leaching of loess soil

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science china Earth sciences 2006年第9期49卷 1002-1008页

作者： LI Yong1,2, ZHANG Qingwen1,2, WAN Guojiang3. HUANG Ronggui3. PIAO Hechun3. BAI Lingyu2 & LI Lu2 1. State Key Laboratory of soil Erosion and Dryland Farming on the Loess Plateau, institute of soil and Water Conservation,{3., Yangling 712100, china 2. institute of Agro-Environment and Sustainable Development, chinese academy of Agricultural sciences, Beijing 100081, china 3. institute of Geochemistry,{3., Guiyang 550002, china 1. State Key Laboratory of soil Erosion and Dryland Farming on the Loess Plateau Institute of Soil and Water Conservation Chinese Academy of Sciences Yangling 712100 China 2. institute of Agro-Environment and Sustainable Development Chinese Academy of Agricultural Sciences Beijing 100081 China 3. institute of Geochemistry Chinese Academy of Sciences Guiyang 550002 China

Plant roots have potential impacts on soil mineral weathering and *** objective is to understand the physical mechanisms of plant roots affecting weathering andleaching of loess soil. Root densities were measured through the method of a large-size dug profile,and transport fluxes of soil elements were determined using an undisturbed monolith soilinfiltration device on the hilly and gully regions of the chinese Loess Plateau. The results showthat the improvement effects of soil environment by plant roots are mainly controlled by the densityand weight of the fibrous roots with the diameters less than 1 mm. Plant roots have the strongereffects on soil physical properties than chemical properties. The principal components analysis(PCA) indicates that soil physical properties by plant roots account for 56.7% of variations in soilenvironment whereas soil chemical properties and pH contribute about 24.2% of the soil *** roles of plant roots in controlling soil weathering and leaching increased in the followingorder: infiltration enhancement > increase of bio-active substance > stabilization of soilstructure. The effects of plant roots on soil mineral weathering and leaching can be quantifiedusing the multiple regression models with the high prediction accuracies developed in this study.

关键词： plant roots, soil weathering and leaching rates, soil environment field, principal components analysis (PCA), chinese Loess Plateau.

^(40)Ar/^(3.)Ar dating of shear deformation of the Xianshuihe fault zone in west Sichuan and its tectonic significance

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science china Earth sciences 2004年第9期47卷 794-803页

作者： ZHANG Yueqiao1, CHEN Wen2, 3.& YANG Nong1 1. institute of Geomechanics, chinese academy of Geological {3., Beijing 100081, china 2. institute of Geology, chinese academy of Geological {3., Beijing 10003., china 3. institute of Geology and Geophysics, chinese academy of sciences, Beijing 100029, china institute of Geomechanics Chinese Academy of Geological Sciences Beijing 100081 China institute of Geology Chinese Academy of Geological Sciences Beijing 100037 China institute of Geology and Geophysics Chinese Academy of Sciences Beijing 100029 China

Based on field geological survey, structural measurements and classical Ar/Ar dating of mica, biotite and K-feldspar, we obtain cooling ages for Miocene left-lateral shear along the Xianshuihe fault zone. The results document two thermal events during the sinistral shear. The early event (12-10 Ma) corresponds to rapid cooling of the Zheduoshan granitic massif from above 700℃ to below 3.0℃. The late event (5-3.5 Ma) corresponds to cooling of granites intruded along the eastern side of the fault zone. These dating results provide important thermochronological constraint on the timing of late Cenozoic eastward extrusion of the Chuan-Dian Block in the SE Tibetan margin.

关键词： Xianshuihe fault zone, Zheduoshan granitic massif, sinistral shear deformation, 40Ar/3.Ar dating, late Cenozoic.

Concatenating construction of the multisymplectic schemes for 2+1-dimensional sine-Gordon equation

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science china Mathematics 2004年第1期47卷 18-30页

作者： WANG Yushun, WANG Bin & QIN MengzhaoLASG, institute of Atmospheric Physics, chinese academy of sciences, Beijing 100029, china School of Mathematics and Computer {3., nanjing Normal University, nanjing 210097, china School of Mathematics and System {3., chinese academy of sciences, Beijing 100080, china 1. LASG Institute of Atmospheric Physics Chinese Academy of Sciences 100029 Beijing China 2. School of Mathematics and Computer science Nanjing Normal University 210097 Nanjing China 3. School of Mathematics and System science Chinese Academy of Sciences 100080 Beijing China

In this paper, taking the 2+1-dimensional sine-Gordon equation as an example, we present the concatenating method to construct the multisymplectic schemes. The method is to discretizee independently the PDEs in different directions with symplectic schemes, so that the multisymplectic schemes can be constructed by concatenating those symplectic schemes. By this method, we can construct multisymplectic schemes, including some widely used schemes with an accuracy of any order. The numerical simulation on the collisions of solitons are also proposed to illustrate the efficiency of the multisymplectic schemes.

关键词： 2+l-climensional sine-Gordon equation multisymplectic scheme concatenating method solitons

Occurrences of Permian radiolarians in central and eastern Nei Mongol(Inner Mongolia) and their geological significance to the Northern china Orogen

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chinese science Bulletin 2004年第24期49卷 2613-2619页

作者： SHANG Qinghua nanjing institute of Geology and Paleontology,chinese {3. of sciences,nanjing 2.0008,china institute of Vertebrate Paleontology and Paleoanthropology,chinese {3. of sciences,Beijing 100044,china nanjing institute of Geology and Paleontology Chinese Academy of Sciences Nanjing 210008 China

The Zhesi (Jisu) Formation of the Middle Per- mian in Nei Mongol (Inner Mongolia) was commonly con- sidered to be a shallow marine sequence. Here I report the radiolarians found in the argillite bed of that formation in Zhesi and Xilinhot areas. This fact indicates a deep marine sedimentary facies persisted during the Middle Permian, and suggests that the ocean between the North china Block and Siberian Craton was not closed until the Late Guadalupian. The suture of this two blocks is probably extends along the Linxi ophiolite belt, south of the Hegenshan ophiolite belt.

关键词：造山带地质意义内蒙古放射虫二叠纪

CONVERGENCE AND SUPERCONVERGENCE OF HERMITE BICUBIC ELEMENT FOR EIGENVALUE PROBLEM OF THE BIHARMONIC EQUATION

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Journal of Computational Mathematics 2001年第2期19卷 139-142页

作者： Dong-sheng Wu (institute of Systems science, academy of Mathematics and Systems {3., chinese academy of sciences, Beijing 100080, china ) 中科院系统科学所北京 100080

Provides information on a study which discussed the convergence and superconvergence for eigenvalue problem of the biharmonic equation using the Hermite bicubic element. Discussion on eigenvalue problem for biharmonic equation; Background on asymptotic error expansions and interpolation postprocessing; Superconvergence approximations to the eigenvalue and eigenfunction.

关键词： Hermite bicubic element biharmonic equation interpolation postprocessing eigenvalue problem