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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. nanjing institute of {2. & limnology, chinese academy of sciences, nanjing 210008, china 2. The Key Laboratory of Industrial Biotechnology, Ministry of Educa- tion, Southern Yangtze University, Wuxi 2.4036, china 3. School of Biotechnology, Southern Yangtze University, Wuxi 2.4036, china nanjing institute of {2. & limnology 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 1980s into State 2.after the 1980s, the large and medium lakes typical of Taihu Lake evolve from State 1-2.in the 1960s into State 8 in the 1980s then into State 9 in the 1990s, the medium and small shallow lakes typical of Honghu Lake evolve from State 1 in the 1960s into State 2.after the 1980s and the small city (suburban) lakes typical of Donghu Lake evolve from State 2.in the 1960s into State 9 after the 1970s. Further, the 1980s 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 1990s is that of Taihu Lake into eutrophic state and the 1970s 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

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Estimation of annual actual evapotranspiration from nonsaturated land surfaces with conventional meteorological data

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Science china Earth sciences 2004年第3期47卷 239-246页

作者： QIU Xinfa1, ZENG Yan2. MIAO Qilong1 & YU Qiang2.1. Department of geography, nanjing {2. of Meteorology, nanjing 2.0044, china 2. {2. of Geographic sciences and Natural Resources Research, chinese academy of sciences, Beijing 100101, china nanjing Inst Meteorol Dept Geog Nanjing 210044 Peoples R China chinese Acad Sci Inst Geog Sci Beijing 100101 Peoples R China chinese Acad Sci Nat Resources Res Beijing 100101 Peoples R China

Views diverge greatly on the relationship between actual evapotranspiration (AE) and potential evapotranspiration (PE). Penman showed that AE is determined in intensity by PE and changes proportionally as a function of PE. In contrast, Bouchet indicated that AE deter-mines PE and varies inversely with PE. Based on nearly 30 years data from 432.weather stations and 512.hydrological stations in china, the two different theories, Penman抯 assumption and Bouchet抯 complementary relationship between AE and PE, were tested on nine river basins. With data integration technique, the complementary relationship between AE and PE was dis-played entirely. A general model to estimate the actual evapotranspiration from nonsaturated surfaces by routine meteorological observations has been established on the basis of thorough analysis of the concept of PE. The results show that the calculations are all in error control of <10%, except for a few years over the Yellow River Basin.

关键词： complementary relationship of evapotranspiration, potential evapotranspiration, actual evapotranspiration.

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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 institute of {2. & limnology, CAS, nanjing 210008People’s Republic of china) nanjing Inst of Geogr + limnology 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). (3) 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

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STUDY ON URBAN LAND SAVING IN THE ECONOMICDEVELOPED COASTAL REGION OF china

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chinese Geographical Science 2001年第1期11卷 11-16页

作者： SHEN Jian-rong, CHEN Shuang, YAO Shi-mou (Department of Urban and Resources Science, nanjing University, nanjing 2.0093, P. R.{2. nanjing institute of geography and limnology, the chinese academy of sciences, nanjing 210008, P. K{2.) Department of Urban and Resources Science Nanjing University Nanjing P. R. China nanjing institute of {2. and limnology the Chinese Academy of Sciences Nanjing P. R. China

In the initial period of industrialization a great deal of land is needed for chinese industry development as well as land resource per person of china is much lower than the average value in the world, thus it is necessary to save land in chinese urban constrUction. This paper mainly discussed the features of urban land use in economic developed coastal cities: one is that the index of urban land per person in middle-small cities was higher than in large cities; another is that urban land has not been used highly and strongly; the third is that the industrial land occupied an irrationally large percentage of whole urban land; the final is that rural enterprises took up a quantity of land. Thereafter, this paper put forward five land-saving measures: first, to adopt the idea of saving land; next, to adjust the land-use structure when redeveloping the old city and alternate some land use when adjusting the industry structure of the city; the third, to develop the system of payment for using land and the management of urban planning; finally to enhance the effective regional plan and the urban landuse plan.

关键词： cities land saving measures the coastal region of china

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Origin of the Red Earth sequence on the northeastern Tibetan Plateau and its implications for regional aridity since the middle Miocene

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Science china Earth sciences 2006年第5期49卷 505-517页

作者： WANG Xianyan1,7, LU Huayu1,2. JI Junfeg3, WANG Xiaoyong1,7, ZHAO Jingbo4, HUANG Baochun5 & LI Zhen6 1. SKLLQG, institute of Earth Environment, chinese academy of sciences, Xi’an 710075,{2. 2. Department of Urban and Resources sciences, nanjing University, nanjing 2.0093,{2. 3. Department of Earth sciences, nanjing University, nanjing 2.0093,{2. 4. Department of geography, Shaanxi Normal University, Xi’an 710062.{2. 5. institute of Geology and Geophysics, chinese academy of sciences, Beijing 10002.,{2. 6 Department of geography, Qinghai Normal University, Xining 810008,{2. 7. Graduate School of the chinese academy of sciences, Beijing 100039,{2. 1. SKLLQG Institute of Earth Environment Chinese Academy of Sciences Xi’an 710075 China 7. Graduate School of the chinese academy of sciences Beijing 100039 China 2. Department of Urban and Resources sciences Nanjing University Nanjing 210093 China 3. Department of Earth sciences Nanjing University Nanjing 210093 China 4. Department of geography Shaanxi Normal University Xi’an 710062 China 5. institute of Geology and Geophysics Chinese Academy of Sciences Beijing 100029 China 6. Department of geography Qinghai Normal University Xining 810008 China

The Red Earth deposit around Xining, northeastern Tibetan Plateau, has beenstudied in terms of soil micro-structure, grain-size distribution, major- and trace-elementchemistry and magne-tostratigraphy. Field investigations indicate that the Red Earth sequenceconsists of 2. visually definable yellow-brown and weakly-developed soils interbedded with reddishstrongly-developed soils, and has a similar structure to the aeolian Red Clay deposit on the chineseLoess Plateau. Grain-size analysis shows that the Red Earth deposit is very fine-grained with anegligible sand fraction ( > 63 μm). Thin-section observations under light microscopy show that thedeposit has a clayey texture and the coarse fraction ( > 10 μm) mainly consists of quartz,feldspar and micas. Pyroxene and hornblende were also observed. This mineralogical composition ofthe coarse fraction is similar to that of the Quaternary loess. In addition, all of the mineralgrains are semi angular semi-angular and are generally finer than 63 μm. There is a good agreementbetween the major and minor trace element chemistry of loess-soil units and the Red Earth *** REE distributions of the loess-soil and the Red Earth deposit are similar in shape, withenriched LREE and fairly flat HREE profiles and a clear negative Eu anomaly. The geochemicalcharacteristics of the Red Earth deposit are also identical to those of upper continental crust,thus indicating a wind-blown origin. Magnetostratigraphic investigation shows that onset of the RedEarth deposition predates 11.4 Ma BP (13.6 Ma at a nearby site). The distribution of the reportedMiocene aeolian loess at Qin''an of the Loess Plateau is still unknown. Our results indicate thatthis aeolian deposit had extended to the northeastern Tibetan Plateau by at least the middleMiocene. The similarity of the element geochemistry between the Red Earth deposit and the overlyingloess shows that they may have similar sources and dynamic transport system, and may indicate thatthe

关键词： Red Earth deposit, Northeastern Tibetan Plateau, aeolian deposit, aridity of Asia, the middle Miocene.

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Geophysical survey on the tectonic and sediment distribution of Qinghai Lake basin

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Science china Earth sciences 2006年第8期49卷 851-861页

作者： AN Zhisheng1, WANG Ping2. SHEN Ji3, ZHANG Yixiang2. ZHANG Peizhen4, WANG Sumin3, LI Xiaoqiang1, SUN Qianli1, SONG Yougui1, AI Li1, ZHANG Yechun2. JIANG Shaoren2. LIU Xingqi3 & WANG Yong31. institute of Earth Environment, chinese academy of sciences (CAS), Xi’an 710075,{2. 2. South{2. Sea institute of Oceanology, CAS, Guangzhou 510301,{2. 3. nanjing institute of geography and limnology, CAS, nanjing 210008,{2. 4. institute of Geology,{2. Earthquake Administration, Beijing 10002.,{2. 1. institute of Earth Environment Chinese Academy of Sciences (CAS) Xi’an 710075 China 2. South china Sea institute of Oceanology CAS Guangzhou 510301 China 3. nanjing institute of {2. and limnology CAS Nanjing 210008 China 4. institute of Geology China Earthquake Administration Beijing 100029 China

The intensive geophysical survey of Qinghai Lake reveals the buried depth of lake sediments and their distribution features. The result indicates that there are three important inter- phases of Qinghai Lake sediments: T1 is the rife interphase of the lake, above which sediments are spread all over the lake basin with roughly the same thickness; T5 is the interphase from which the neotectonic sedimentary cycle begins, and its above sedimentary environment is relatively stable; Tg is the base of the lake basin. Five west-northwest (WNW) fault belts defined the tectonic structure of Qinghai Lake basin: the central hunch around Haixin Shan with two subbasins both in its north and south. The thickness of the lake sediments varies at different places, the thickest sediments are found within the two subbasins. According to the depth that the Sparker System can reach, sediment in the northern subbasin is deeper than 560 m, while sediment in the southern subbasin is deeper than 700 m. The correlation between the seismic sequence stratigraph and the lithology of onshore core shows that Qinghai Lake sediments consist of muddy silt, clay silt, silty clay, gravel silty clay, etc.

关键词： sediment, geophysical survey, Qinghai Lake.

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Estimation of internal nutrient release in large shallow Lake Taihu, china

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Science china Earth sciences 2006年第z1期49卷 38-50页

作者： QIN Boqiang, ZHU Guangwei, ZHANG Lu, LUO Liancong, GAO Guang & GU Binhe nanjing institute of {2. & limnology, chinese academy of sciences, nanjing 210008, china Everglades Department, South Florida Water Management District, 3301 Gun Club Road, West Palm Beach, FL 33406, USA chinese Acad Sci Nanjing Inst Geog & Limnol Nanjing 210008 Peoples R China S Florida Water Management Dist Everglades Dept W Palm Beach FL 33406 USA

Based on field investigation of wave, sediment suspension and the changes in nutrient concentration of the water column in Lake Taihu, china, we proposed two release models to quantify nutrient release under static and dynamic conditions, respectively. Under static conditions, nutrient release from sediments to the overlying water mainly depends on chemical diffusion induced by concentration gradient, in which the nutrient release is controlled by the temperature, dissolved oxygen concentration in the sediment-water interface, oxidation-reduction potential and the concentration difference between porewater and overlying water. Under dynamic condition (or disturbed condition),both dissolved and particulate nutrients in sediments are released into the water column because of wind-induced sediment suspension. The amount of nutrient release under dynamic conditions is larger than that under the static condition. The release of dissolved nutrients, however, does not increase because the wind induced turbulence made oxidation of metallic elements such as Fe (ferric iron), Mn which are capable of precipitating soluble reactive phosphate (SRP). Under dynamic conditions, therefore, the release of total phosphorus (TP) increases dramatically but the release of SRP is close to those under static conditions. In sediments of Lake Taihu, high Fe content leads to a high ratio of Fe to P contents in sediments (Fe:P ratio). Under dynamic conditions, therefore, nutrient release is controlled by the intensity of disturbance, sediment consolidation and nutrient content in *** for dissolved nutrients, especially SRP, the release is also controlled by the intensity of dynamic re-oxidation, Fe content in sediments and nutrient concentration gradient between porewater and overlying water. Based on these two release modes, the release flux in Lake Taihu has been estimated. In the static condition (i.e. laboratory experimental condition), total release of NH4+-N for whole lake is ca

关键词： shallow lake, eutrophication, internal loading, sediment, nutrient, dynamic turbulence.

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CLIMATIC VARIATIONS IN china OVER THE LAST 2.00 YEARS

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chinese Geographical Science 2001年第2期11卷 97-103页

作者： YANG Bao1, SHI Ya-feng2. LI Heng-peng2.(1. Cold and Arid Regions Environmental and Engineering Research institute, the chinese academy of sciences,Lanzhou 730000, P.R.{2. 2. institute of geography and limnology, the chinese academy of sciences Cold and Arid Regions Environmental and Engineering Research institute the Chinese Academy of Sciences Lanzhou P. R. China institute of geography and {2. the Chinese Academy of Sciences Nanjing P. R. China

A compilation of paleoclimate records from ice core, tree-rings, lake sediments and historical documents provides a view of temperature change in china over the recent 2.00 years. For all-china temperature reconstruction, six sub-stages are identified for the last two millennia. Around AD 0－2.0, AD 800－1100, AD 132.－1400 and the period from AD 1880 on were warm while around AD 2.0－800, AD 1100－132., AD 1400－1880 were cold. Also, temperature varied from region to region in each of the warm or cold periods. The Eastern Han warm period (0－AD 2.0), the cold period covering the span of Wei, Jin, and the Southern and Northern Dynasties, the MWP (AD 800－1100) and succeeding LIA occurred in eastern china and the Qilian Mountains. Only the first two climatic events were recorded in Guliya ice core while the so-called MWP and LIA was far weaker. Also, the warming between AD 800 and 1100 didn′t occur in the south of Xizang (Tibet) Plateau. Instead, the southern Xizang Plateau experienced warming in AD 1150－1400. The aggregated china temperature agrees well with North-hemisphere temperature in the past millennia, indicating close relationship of temperature changes between china and North-hemisphere.

关键词： climatic variations the last two millennia china

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New species and new records of diatoms from Lake Fuxian,china

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Journal of Systematics and Evolution 2010年第1期48卷 65-72页

作者： 1 Yan-Ling LI 1 Zhi-Jun GONG 2.Chun-Chao WANG 1 Ji SHEN 1(State Key Laboratory of Lake Science and Environment,nanjing institute of {2. and limnology,chinese academy of sciences,nanjing 210008,china) 2.nanjing institute of Geology and Palaeontology,chinese academy of sciences,nanjing 210008,china) (State Key Laboratory of Lake Science and Environment Nanjing Institute of Geography and Limnology Chinese Academy of Sciences Nanjing 210008 China) (nanjing institute of Geology and Palaeontology Chinese Academy of Sciences Nanjing 210008 China) *Correspondence: Yan-Ling LI *Correspondence: *?Author for correspondence. E-mail: ylli@*** Tel.: 86-2.-86882.40 Fax: 86-2.-57713063.

One new species,four newly recorded genera,and two newly recorded species of diatoms are described from *** are Sellaphora fuxianensis ***,Sellaphora Mereschkowsky,Karayevia Round & Bukhtiyarova,Placoneis Mereschkowsky,Fallacia Stickle & Mann,Placoneis prespanensis Levkov,Krstic & Nakov,and Fallacia lucinensis(Hustedt) *** taxa were collected from Lake Fuxian in Yunnan Province,*** species were observed with light and scanning electron microscopes,and their taxonomic characters are discussed.

关键词： china diatom new records new species.

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The changes of Lop Nur Lake and the disappearance of Loulan

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Journal of Arid Land 2010年第4期2卷 295-303页

作者： ZhiChao WANG Xinjiang institute of Ecology and geography,{2., Urumqi 830011, china chinese Acad Sci Xinjiang Inst Ecol & Geog Urumqi 830011 Peoples R China

The causes of the disappearance of the ancient town of Loulan in Xinjiang, china have been generally agreed to derive from two factors: human activities and natural factors (environmental variations). In this paper, the Muzart Glacier was selected as an example, and found that the length of the glacier has been gradually decreasing and the snow line has been retreating to a higher altitude, both results contributing to a decrease in river flow below the Muzart Glacier. From the distribution of moraines in the Tianshan Mountains and adjacent areas in different periods, the paper speculates that there have been four minor glacial periods since the Quaternary. Although the durations and scales of the four minor glacial periods were different, they all indirectly influenced the formation and disappearance of the Lop Nur Lake. The events of the fourth minor glacial period are the important impact factors in the existence and disappearance of Loulan. Whether the disappearance of Loulan can be related to the events of the three previous minor glacial periods needs further investigation.

关键词： glacier moraine Loulan Lop Nur

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