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The reconstruction and interpretations of lake status at 6 ka and 1. ka *** inland mainland Asia

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Chinese Science Bulletin 1998年第14期43卷 1145-1157页

作者： QIN Boqiang 1. SHI Yafeng 1.and YU Ge 2, 3.1. {1. {1. of geography & {3., Chinese Academy of Sciences, nanjing 21.008, china 2. Dynamic Palaeoclimatology, Lund University, PO Box 1.7, S 221.00, Lund, Sweden 3. Department of nanjing{1. of geography & Limnolagy Chinese Academy of Sciences Nanjing China Dynamic Palaeoclimatology Lund University Lund Sweden Department of Geology and Ocean Sciences Nanjing University Nanjing China

By means of survey of literature through compilations of sedimentological, biogeological and geomorphologic data, the inland lake level changes in arid or semi arid mainland Asia at 6 and 1. ka B.P. have been reconstructed. The results showed that the lakes from western and northwestern Asia were characterized by very high water levels at 1. ka B.P., but low or intermediate water stands at 6 ka B.P. The high lake level in this region was associated with the southward displacement of westerlies, therefore, the extent of the high lake stand indicated the southern flank of westerlies during the glaciation. Conversely, the lakes from the eastern and southern Asia registered comparative low levels at 1. ka B.P. and significantly high one at 6 ka B.P. The lowering of lake level at 1. ka B.P. was caused by the weakened summer monsoon and the high lake level at 6 ka B.P. by the enhanced summer monsoon induced by the enlarged thermal contrast between land and ocean. The extent of high lake levels indicated the northern boundary of monsoon expansion. Between the above two regions, there is a climatic transitional zone in the Central Asia where the lake behavior was close to that in southeastern Asia at 6 ka B.P. but became similar to that in northwestern Asia at 1. ka B.P. Thus this zone became a transitional sector from the monsoon to the westerlies.

关键词： lake status inland mainland Asia westerlies monsoon.

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, {1. {1. of geography and {3., Chinese Academy of Sciences, nanjing 21.008, china 2. {1. of Tibetan Plateau Research, Chinese Academy of Sciences, Beijing 1.085, china 3. Graduate University of Chinese Academy of Sciences, Beijing 1.003., 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 1.C, 21.Pb and 1.0}Cs dating are mainly used to establish the chronology for recent several ten thousand years. Because of being mixed with “dead carbon”, the measured 1.C 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. 21.Pb 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 1.C dating is stronger. Based on the analysis on results of 1.C, 21.Pb and 1.0}Cs of the lacustrine sediments from Co Ngoin, central Tibetan Plateau, we use the simple regression method to re-calculate the 1.C calendar ages, and establish the time sequence for cores CE-1.and CE-2 with result of 21.Pb CRS model for the upper 3. cm and re-calculated 1.C calendar age for sediments bellow 3. cm. Since 1.00 cal. a BP, sedimentation inter-rupted for more than 1.00 years. According to this time sequence, variations of environmental proxies confidently reflect the major climatic events in Holocene.

关键词： 1.C, 21.Pb and 1.0}Cs, chronology, lacustrine sediments, climatic event, Co Ngoin, central Tibetan Plateau.

Research on the evaluation model of the modernization level of urban construction in Jiangsu Province,china

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Science china(Technological Sciences) 2010年第9期53卷 2510-2514页

作者： YANG JunYan1.& CHEN Wen2 1.School of Architecture,Southeast University,nanjing 21.096,{1. 2 nanjing {3. of geography and limnology,Chinese Academy of Sciences,nanjing 21.008,{1. 1. School of Architecture Southeast University Nanjing 210096 China2. Nanjing Institute of Geography and Limnology Chinese Academy of Sciences Nanjing 210008 China

The modernization of urban construction is a key index in the process of urbanization,and also is an important index to measure the level of socio-economic and cultural *** paper analyzes and explores the related concepts of modernization of urban construction,analyzes the situation and identity of urban construction layer by layer so as to establish an evaluation index system of the modernization level of urban construction and then the paper evaluates the modernization level of urban construction from four different angles,which are the perspectives of the urban planning control,the level of urban facilities,urban management,urban construction *** later analyzes the evaluation results by choosing Jiangsu Province as a research hierarchy from the scale chains of urban study and makes efforts to the operative and directive development direction.

关键词： modernization of urban construction index system evaluation model

An analysis on the evolvement processes of lake eutrophication and their characteristics of the typical lakes in the middle and lower reaches of Yangtze River

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Chinese Science Bulletin 2006年第13期51卷 1603-1613页

作者： CHENG Xiaoying1.2,3.& LI Shijie1.1. {1. {1. of geography & {3., Chinese Academy of Sciences, nanjing 21.008, china 2. The Key Laboratory of Industrial Biotechnology, Ministry of Educa- tion, Southern Yangtze University, Wuxi 21.03., china 3. School of Biotechnology, Southern Yangtze University, Wuxi 21.03., china nanjing{1. of geography & {3. Chinese Academy of Sciences Nanjing China The Key Laboratory of Industrial Biotechnology Ministry of Education Southern Yangtze University Wuxi China School of Biotechnology Southern Yangtze University Wuxi China

According to the study on the aquatic environment of the typical lakes in the middle and lower reaches of Yangtze River, lake eutrophication is a process in which the lake ecosystem degenerates, resulting in the deterioration of the water quality due to the enrichment of the nutrients. Moreover, the succession of lake ecosystem and change of water quality both couple well with the evolvement of tro- phic state. Then the conceptual model is mentioned and ten lake states are classified. Based on these, the authors analyzed the eutrophication processes of the typical lakes in the middle and lower reaches of Yangtze River. The large lakes with taking in - send- ing out water typical of Poyang Lake evolve from State 1.before the 1.80s into State 2 after the 1.80s, the large and medium lakes typical of Taihu Lake evolve from State 1.2 in the 1.60s into State 8 in the 1.80s then into State 9 in the 1.90s, the medium and small shallow lakes typical of Honghu Lake evolve from State 1.in the 1.60s into State 2 after the 1.80s and the small city (suburban) lakes typical of Donghu Lake evolve from State 2 in the 1.60s into State 9 after the 1.70s. Further, the 1.80s is the key con- version period of the lakes of various types typical of Poyang Lake, Honghu Lake and Taihu Lake con- verting into mesotrophic state, the 1.90s is that of Taihu Lake into eutrophic state and the 1.70s is thatof the small city (suburban) lakes typical of Donghu Lake into eutrophic state. The series of nutrient evolvement of different typical lakes are similar, but the processes are not synchronous, which is related to the various human and natural driving mechanisms in lake basins.

关键词：长江湖泊富营养化概念模型转变时期驱动机制

New progress of lake sediments and environmental changes research in china

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Chinese Science Bulletin 1999年第19期44卷 1744-1754页

作者： WANG Sumin and ZHANG ZhenkeLaboratory of Lake Sediment and Environment, nanjing{1. of geography and {3., Chinese Academy of Sciences , nanjing 21.008, china Department of geography and Oceanology, nanjing University , nanjing 21.093., china Laboratory of Lake Sediment and Environment Nanjing Institute of Geography and Limnology Chinese Academy of Sciences Nanjing China Department of geography and Oceanology Nanjing University Nanjing China

Environmental change recorded by lake sediments is one of the important branches of the past global changes study. The new progress of lake sediments and environmental changes in china since the late 1.80s has been comprehensively discussed. The highlights emphasized are Asian paleomonsoon migration reflected by lake level fluctuation, uplift of the Qinghai-Xizang Plateau recorded by lacustrine sediments, saltlake sediments and

关键词： lake sediments environmental change.

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, {1. of Earth Environment, Chinese Academy of Sciences, Xi’an 71.075, china 2. Graduate University of Chinese Academy of Sciences, Beijing 1.003., china {3., Chinese Academy of Sciences, nanjing 21.008, 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{1. 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, 1.―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.

A high-resolution late Pleistocene record of pollen vegetation and climate change from Jingning, NW china

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Science china Earth Sciences 2006年第2期49卷 154-162页

作者： LI Chunhai1., TANG Lingyu1. FENG Zhaodong3.4, ZHANG Hucai2, WANG Weiguo3.& AN Chenbang3.1. nanjing {1. of Geology and Palaeontology, Chinese Academy of Sciences, nanjing 21.008,{3. 2. Nanjng {1. of geography and limnology, Chinese Academy of Sciences, nanjing 21.008,{3. 3. Environment and Resources College, Lanzhou University, Lanzhou 73.000,{3. 4. Beijing Normal University, Beijing 1.0875,{3. 1. nanjing{1. of Geology and Palaeontology Chinese Academy of Sciences Nanjing 210008 China 2. Nanjng institute of{1. and limnology Chinese Academy of Sciences Nanjing 210008 China 3. Environment and Resources College Lanzhou University Lanzhou 730000 China 4. Beijing Normal University Beijing 100875 China

With the support of 1. AMS-1.C data, a high-resolution pollen record from the Suancigou section at Jingning, Gansu Province was established. Our results showed that the vegetation ex-perienced a series of changes characterized by the alternative growth and decline of forest and steppe components during the period from 44.2 to 1. ka B.P. in the Jingning area. Over the period of 44―29 ka B.P. (MIS3., coniferous forests were flourishing, indicating a humid climate with the tem-perature being lower than that of the present. Since 23.ka B.P., the vegetation was dominated by steppe-desert steppe under a cold and dry condition, and entered the Last Glacial Maximum domi-nated by desert steppe. Several periods of the marked decrease in the arborous pollen content in Suancigou well corresponded to the North Atlantic Heinrich events, especially to Heinrich event 3. further supporting that the Heinrich events were well reflected by the pollen record in the Loess Pla-teau as well.

关键词： Western Loess Plateau, pollen record, climatic change, late Pleistocene.

Alkaline phosphatase activity and the phosphorus mineralization rate of Lake Taihu

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Science china Earth Sciences 2006年第z1期49卷 176-185页

作者： GAO Guang, ZHU Guangwei, QIN Boqiang, CHEN Jun & WANG Ke nanjing{1. of geography & {3., Chinese Academy of Sciences, nanjing 21.008, china Hohai University, nanjing 21.098, china Chinese Acad Sci Nanjing Inst Geog & Limnol Nanjing 210008 Peoples R China Hohai Univ Nanjing 210098 Peoples R China

The phosphorus fractions, the alkaline phosphatase activity (APA) and other water chemical parameters were concomitantly monitored from April 2003.to October 2004 in different ecotype sites of Lake Taihu. During the stages of algae growth, the phosphorus fractions and their relationships with APA in different ecotype sites were discussed and the phosphorus mineralization rate was calculated. In the water of Lake Taihu, most of the phosphorus (70.2%) could be attributed to the suspended particulate phosphorus, while the dissolved reactive phosphorus (DRP) seems to contribute less than 7%. About 58% of the total phosphorus, however, can be hydrolyzed as inorganic phosphate to compensate for phosphorus deficiency of algae and bacteria growth. During the different algae growth stages, the APA and its Kinetic parameters were varied significantly between different ecotype sites of Lake Taihu. This trend is also visible by comparing the phosphorus mineralization rate,and the most rapidly phosphorus turnover time is only several minutes. The fast recycle of phosphorus can, to some extent, be explained that the phosphorus source of algal blooms. The phytoplankton seems to compensate for phosphorus deficiency by using the alkaline phosphatase to hydrolyze phosphomonoesters.

关键词： Lake Taihu, alkaline phosphatase, kinetic parameters, phosphorus, mineralization rate.

AN APPROACH ON SEVERAL PROBLEMS OF china'S URBANIZATION DEVELOPMENT

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Journal of Geographical Sciences 1996年第2期6卷 35-41页

作者： Chen Wen(nanjing{1. of geography & {3., CAS, nanjing 21.008People’s Republic of china) nanjing Inst of Geogr +{1. CAS Nanjing 210008 China

china, having urique national conditions, is facing a basic contradiction between large numbers of less educated surplus rural labor forces and limited capacities of urban employment and infrastructure on the urbanization ***, the urbanization model should prevail in comprehensive and several ways: (1.On occupational and spatial shift rural surplus labors, two fashions of 'leaving land bot not countryside' and 'leaving both land and countryside' should be integrated with joint effort of cities and countryside. (2) On urbanization motive, urban construction will be invested by not only the govermment (from the upper), but the locality, personnel and foreigners (from the lower). ({1. On urban scales, metropolis,large, medium-sized and small cities and towns should play fully their roles to absorb rural surplus lanors. Thereby, the present urban development policy needs to be rectified, which this paper has discussed particularly. (4) On account of great regional disparities in china, urban development should perform different models in different regions. In addition, this paper has also focused on the problem and its primary countermeasures of 'labor force mass', a hot issue closely related to urbanization and rural labor transfer.

关键词： national conditions urban development model urban development policy,rural labor mass