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Palaeoclimate simulation of Little Ice Age

Progress in Natural Science:Materials International 2004年第8期 68-76页

作者： LIU Jian 1. CHEN Xing 2, WANG Sumin 1.and ZHENG Yiqun 1. (1. nanjing{1. of geography and {3., Chinese Academy of Sciences, nanjing 21.008, china 2. Department of Atmospheric Science, nanjing University, nanjing 21.093. china) nanjing{1. of geography and {3. Chinese Academy of Sciences Nanjing 210008 China Department of Atmospheric Science Nanjing University Nanjing 210093 China

Little Ice Age (LIA) is a typical cold climate period in global scope with a profound impact upon human society. In this study, a coupled global atmospheric circulation model including the land processes (AGCM + SSiB) is used to perform the simulation of LIA climate. Under the control of solar radiation reduction mechanism, the decrease of temperature is more obvious in summer than in winter; meanwhile, there is regional difference in the change of winter temperature. But the temperature decrease is the main characteristic of the annual mean temperature. Volcanic dust has an evident effect on the winter temperature decrease, but to a less extent than the solar radiation. The synchronous function caused by the reduction of solar radiation and the increase of optic depth of volcanic dust has a superposed strengthening effect on the temperature decrease in large regions. Promotion of the vegetation cover rate profits the increase of temperature, and vise versa. Certain decrease of solar radiation will favor the increase of summer monsoon precipitation in East Asia. The increase of optic depth of volcanic dust does not have a significant effect on the annual precipitation in most parts of Eurasian continent. The composite effect of the decrease of solar radiation and the increase of volcanic dust makes the summer monsoon precipitation in East china increase, and that in South Asia decrease. Together with vegetation change, the result shows that precipitation increases with the increase of vegetation coverage (e.g. East Asia), and when the vegetation coverage reduces (e.g. North Africa) the precipitation will decrease, too.

关键词： Little Ice Age model simulation East Asia.

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The Current State of china's Freshwater Resources and Related Suggestions

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Bulletin of the Chinese Academy of Sciences 2001年第3期15卷 170-176页

作者： Wu Ruijin(nanjing{1. of geography and {3., CAS) nanjing{1. of geography and {3. CAS

china has many lakes, marshlands and rivers. Due to their uneven geographical distribution and varied degrees of salinity, their exploitable freshwater resources are limited. In the wake of the highspeed growth of national economy in recent years, human infringement upon their natural settings has been increasingly intense, leading to the degeneration of{1.'s lacustrine ecosystems and the degradation of their surrounding environments. Lakes are shrinking and becoming more saline. In arid and semi-arid inland areas, some of them have even disappeared. In addition, lake water pollution and eutrophication in densely populated areas are getting worse, resulting in serious water shortages in some places. Silt deposition in lake basins, water surface shrinkage caused by hectic and irrational reclamation for farmland, the prevalence of flooding and water-logging calamities and ecosystem depletion caused by predatory exploitation of fishery resources, all of these have become restrictive factors in regional sustainable development. The author of this article suggests measures for the protection and sustainable exploitation of limnetic settings in{1..

关键词： OC The Current State of china’s Freshwater Resources and Related Suggestions Lake

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The qanats of Xinjiang:historical development, characteristics and modern implications for environmental protection

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Journal of Arid Land 2012年第2期4卷 211-220页

作者： WenJun HU1.,2,JieBin ZHANG 3.YongQiang LIU 1.1.ohai University,{1. 21.098,china 2The International Economic&Technical Cooperation and Exchange Center,Ministry of Water Resources,Beijing 1.0053. china 3.Xinjiang {3. of Ecology and geography,Chinese Academy of Sciences,Urumqi 83.01.,china Chinese Acad Sci Xinjiang Inst Ecol & Geog Urumqi 830011 Peoples R China Hohai Univ Nanjing 210098 Jiangsu Peoples R China Minist Water Resources Int Econ & Tech Cooperat & Exchange Ctr Beijing 100053 Peoples R China

In china,qanats(kan’erjing/karez)exist only in Xinjiang Uygur autonomous region,being one form of traditional irrigation technology that made great contributions to oasis *** are different opinions on the origin and date of the qanats in Xinjiang due to a lack of adequate *** uncontrolled over-exploitation of groundwater by pumping wells,as well as the expansion of surface water interventions nowadays,has caused serious impacts on not only the qanats,but also local ecological *** exist long-time arguments on whether the qanats should be restored or *** study aimed to examine the historical development, geological conditions and characteristics,and modern implications of the qanats for oasis environmental protection, and to discuss the initiatives taken by local *** whole Xinjiang Uygur autonomous region was included as the study area,with a specific focus on Turpan *** materials and data were obtained from literature review and governmental *** on a systematic examination of three prevailing theories on the origination of Xinjiang’s qanats,it is suggested modern archaeological techniques could be good solutions to explore the origination in addition to historical records used *** qanats fail to fully meet today’s enormous water demands,their rich historical,cultural,ecological and environmental implications in arid areas should not be *** a cultural heritage and ecologically-friendly engineering creation,qanat systems shall be kept in good condition and function by a valuable *** initiatives to protect and restore target qanat systems in Xinjiang could provide positive examples for the practices in other regions of the world where the protection and restoration of qanats or similar technologies are desired.

关键词： arid areas qanat(kan’erjing/karez) groundwater environmental protection oasis Xinjiang

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Discovery of Cathaysiodendron Lee from the Early Carboniferous of Jingyuan,Gansu,western china

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Progress in Natural Science:Materials International 2004年第10期14卷 63-66页

作者： WANG Jun and WU Xiuyuan (nanjing{1. of Geology and Palaeontology,Chinese Academy of Sciences,nanjing{3.,china) Chinese Acad Sci Nanjing Inst Geol & Palaeontol Nanjing 210008 Peoples R China

As one of the representative members of the Late Palaeozoic Cathaysian flora,Cathaysiodendron has been previously recorded from the Early Permian Taiyuan and Shanxi Formations in north *** species of Cathaysiodendron presented here are from the lower member of Chouniugou Formation of Ciyao,Jingyuan,*** overlying marine beds yield fusulinids that are of Visean age in western Europe and conodonts of the Datang Stage in south china,so that the age of the bed containing Cathaysiodendron as Visean,Early Carboniferous,is well *** a record of Cathaysiodendron is significant in terms of Carboniferous phyto-{1. and the evolution of the Cathaysian Lepidophytes.A new species,Cathaysiodendron jingyuanense Wang&Wu *** described and a second one mentioned.

关键词： Cathaysiodendron Early Carboniferous Visean Cathaysian flora

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Sustainable Nutrient Management in Chinese Agriculture: Challenges and Perspective

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Pedosphere 2006年第2期16卷 253-263页

作者： GAO Chao SUN Bo ZHANG Tao-Lin Department of geography Nanjing University Nanjing 210093 （China）. institute of Soil Science Chinese Academy of Sciences Nanjing 2100（78 （China）

china has to raise agricultural productivity in its limited and shrinking farmland to guarantee food security for its huge and ever-growing population. Sustainable soil nutrient management is of paramount importance to the world's most populous country. Critical challenges the country is facing in sustaining soil fertility and in alleviating the hazardous impact of intensive fertilizer use are discussed in this paper. It is emphatically pointed out that national strategies as well as area-specific action plans with respect to scientific nutrient management are urgently needed to balance productivity and sustainability in the future. Relevant proposals for addressing those challenges are also presented.

关键词： china food security nutrient management soil fertility water quality

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DYNAMIC VARIATIONS OF WATER QUALITY IN TAIHU LAKE AND MULTIVARIATE ANALYSIS OF ITS INFLUENTIAL FACTORS

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Journal of Geographical Sciences 1997年第3期7卷 72-82页

作者： Cai Qiming Gao Xiyun Chen Yuwei Ma Shengwei nanjing{1. of geography and {3., CAS, nanjing 21.008 People’s Republic of chinaMartin Dokulil{1. of {3., Austria

Dynamic variation of water quality in Meiliang Bay and part of West Taihu Lake has been analysed based on data from 1.91.to 1.92. Principal Component Analysis is used to reveal the mutual relationships of various factors. It is shown that there existis an obvious spatial and temporal variation in the main factors of water quality. Annual values of TP, CON, TN, Chl-a and conductivity decrease evidently from inner Meiliang Bay to the outer from north to south. TP and TN fluctuate seasonally with much higher value in winter. This is particularly true for the mouth of Liangxi River. In addition, the Chl-1.has a synchronous variation with water temperature, although being lagged a little, and closely relates to TP and TN. Finally, the results from Principal Component Analysis show that TP, TN, SS (or SD), water temperature and Chl-a are the most influential factors to water qualuty in this area, and both suspensions and algae can contribute to transparency to Taihu Lake.

关键词： Taihu Lake dynamic variation water quality principal component analysis.

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Environmental magnetic studies of lacustrine sediments

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Chinese Science Bulletin 2002年第7期47卷 613-616页

作者： HU Shouyun, DENG Chenglong, E. Appel & K. L. Verosubnanjing{1. of geography and {3., nanjing 21.008, china institute of Geology and Geophysics, Beijing 1.01.1. china Institut fur Geologic, Universitat Tubingen, 72076 Tubingen, Germany Departm 1. nanjing{1. of geography and {3. 210008 Nanjing China 2. institute of Geology and Geophysics 100101 Beijing China 3. Institut für Geologie Universit?t Tübingen 72076 Tübingen Germany 4. Department of Geology University of California 95616 Davis CA USA

In recent decades, environmental magnetism has become an important method for studying past global climatic and environmental changes. For an environmental magnetic study, it is important to understand the magnetic properties of various magnetic minerals in lacustrine sediments and the processes involved in the formation, transport, and preservation of these magnetic minerals. The magnetic response of lacustrine sediments to climatic change may vary widely from lake to lake. To reconstruct the processes contributing to paleoclimatic and paleoenvironmental change, it is, therefore, necessary to derive a complete understanding of the potential origin of the magnetic signal observed.

关键词： rock magnetism paleoclimate paleoenvironment lacus-trine sediments.

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Statistical study on the spatial - temporal distribution features of the arctic sea ice extent

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Acta Oceanologica Sinica 1990年第3期9卷 373-387页

作者： Wang Xiaolan, Fan Zhongxiu,Peng Gongbing and Zhou Enji Hohai University, nanjing,{1. institute of {3.,Academia Sinica,Beijing,{1.

On the basis of the arctic monthly mean sea ice extent data set during 1.53.1.84, the arctic region is divided into eight subregions,and the analyses of empirical orthogonal functions, power spectrum and maximum entropy spectrum are made to indentify the major spatial and temporal features of the sea ice fluctuations within 3.-year period. And then, a brief appropriate physical explanation is tentatively suggested. The results show that both seasonal and non-seasonal variations of the sea ice extent are remarkable, and iis mean annual peripheral positions as well as their interannu-al shifting amplitudes are quite different among all subregions. These features are primarily affected by solar radiation, o-cean circulation, sea surface temperature and maritime-continental contrast, while the non-seasonal variations are most possibly affected by the cosmic-geophysical factors such as earth pole shife, earth rotation oscillation and solar activity.

关键词： temporal distribution features of the arctic sea ice extent Statistical study on the spatial

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Angular Distribution of Element Contents in Tree Rings and the Environmental Information

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Pedosphere 1999年第1期9卷 69-76页

作者： KE SHANZHE LIU ZHENGRONG QIAN JUNLONG CHEN RUSONGI and KE XIAOKANG (Physics Department, nanjing University, nanjing 21.095,china)(nanjing institute of Geogmphy and limnology, the Chinese Academy of Sciences, nanjing 21.008, china)(Garded and Greenbelt 南京大学物理系江苏南京 210093 南京大学物理系江苏南京中科院南京地理与湖泊所江苏南京 210008 南京大学化学系江苏南京 210009

Element contents of tree rings and soils near tree roots collected from Deodar cedar (Cedrus deodara (Roxb.) G. Don) and Masson pine (Picks massoniana lamb.) were determined to study the relationship between the angular distribution of element contents in tree rings and the environmental information. The chemical composition and properties of soils are very much complicated, which leads to the non-uniform distribution of the element contents in tree rings. The statistical multi-variable regression method was used to got the information of the tree-centered distribution of element contents in the environment (soil) (C’), C’(z, θj ), from the distribution of element contents in tree rings (C), C(Z, θi), which depends on the plane azimuth angle (θi), i. e., C=C(Z,θi), where Z is the atomic number of the element, with a satisfactory result,though this study is only a primary one.

关键词： angular distribution element contents environmental information tree rings

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Soil Organic Carbon Storage in china

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Pedosphere 2004年第4期14卷 491-500页

作者： XIEXian-Li SUNBo ZHOUHui-Zhen LIAn-Bo instituteofSoilScience ChineseAcademyofSciencesNanjing210008（China）. geographyCollege NanjingNormalUniversityNanjing210097（China）

Soil organic carbon (SOC) storage under different types of vegetations in china were estimated using measured data of 2 440 soil profiles to compare SOC density distribution between different estimates, to map the soil organic carbon stocks under different types of vegetation in china, and to analyze the relationships between soil organic carbon stocks and environmental variables using stepwise regression analyses. Soil organic carbon storage in china was estimated at 69.3. Gt (1. 1. g). There was a big difference in SOC densities for various vegetation types, with SOC distribution closely related to climatic patterns in general. Stepwise regression analyses of SOC against environmental variables showed that SOC generally increased with increasing precipitation and elevation, while it decreased with increasing ***, the important factor controlling SOC accumulation for forests was elevation, while for temperate steppes mean annual temperature dominated. The more specific the vegetation type used in the regression analysis, the greater was the effect of environmental variables on SOC. However, compared to native vegetation, cultivation activities in the croplands reduced the influence of environmental variables on SOC.

关键词： china environmental factors soil organic carbon storage vegetation

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