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Seasonal variation of potential denitrification rates of surface sediment from Meiliang Bay, Taihu Lake, china

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Journal of Environmental Sciences 2010年第7期22卷 961-967页

作者： Jicheng Zhong, Chengxin Fan, Guofeng Liu, Lei Zhang, Jingge Shang, Xiaozhi GuState Key Laboratory of Lake Science and Environment, nanjing institute of {2. and limnology, Chinese Academy of Sciences,{4., china. [a] State Key Laboratory of Lake Science Environment Nanjing Institute of Geography limnology Chinese Academy of Sciences Nanjing 210008 China

The regulatory effects of environmental factors on denitrification were studied in the sediments of Meiliang Bay, Talhu Lake, in a monthly sampling campaign over a one-year period. Denitrification rates were measured in slurries of field samples and enrichment experiments using the acetylene inhibition technique. Sediment denitrification rates in inner bay and outer bay ranged from 2.8 to 51.5 nmol N2.（g dw （dry weight）·hr） and from 1.5 to 81.1 nmol N2.（g dw·hr）, respectively. Sediment denitrification rates were greatest in the spring and lowest in the summer and early autumn, due primarily to seasonal differences in nitrate concentration and water temperature. For each site, positive and linear relationships were regularly observed between denitrification rate and water column nitrate concentration. Of various environmental factors on denitrification that we assessed, nitrate was determined to be the key factor limiting denitrification rates in the sediments of Meiliang Bay. In addition, at the two sites denitrification rates were also regulated by temperature. The addition of organic substrates had no significant effect on denitrification rate, indicating that sediment denitrification was not limited by organic carbon availability in the sediments. Nitrate in the water column was depleted during summer and early autumn, and this suppressed effective removal of nitrogen from Taihu Lake by denitrification.

关键词： denitrification sediment environmental factors Taihu Lake

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. & {4., Chinese Academy of Sciences,{4., china 2. The Key Laboratory of Industrial Biotechnology, Ministry of Educa- tion, Southern Yangtze University, Wuxi 2.4.36, china 3. School of Biotechnology, Southern Yangtze University, Wuxi 2.4.36, 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

Dating sediments on several lakes inferred from radionuclide profiles

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Journal of Environmental Sciences 1998年第1期10卷 58-65页

作者： Xiang Liang Lake Sediment and Environment Laboratory,nanjing institute of {2. & limnology, Chinese Academy of Sciences,nanjing 210008,china

In this paper, several sediment cores from three lakes (Gucheng Lake, Dianchi Lake and Dabusopao Lake) in the different regions of china were dated radiometrically by 2.0 Pb, 137 Cs and in Dianchi also by 2.1 Am. The study shows that the profiles of 137 Cs in lake sediment of china generally have 2.4.distinct chronological markers, i.e. the onset of fallout in 1954.and peak fallout in 1963, 1974.and 1986. As many places of the northern hemisphere, the peak fallout in 1963 was the result of the atmospheric atomic weapons test. But in some areas of china, there may be have one or two other peaks of 137 Cs fallout, one can derive from Chernobyl fallout in 1986 and the other is caused by the nuclear testing fallout in early 1970s. So in these areas, the profiles of 137 Cs can have 2.or 3 peaks as the time markers. 2.1 Am, which is another fallout product from nuclear weapons testing, also provides a useful dating marker in Dianchi. These time markers are of considerable value to confirm 2.0 Pb dates in the three lakes. Despite there are some questions remain concerning the interpretation of these radionuclide records in lake sediments, coupling with 2.0 Pb and 137 Cs (and/or 2.1 Am) is suggested to be a valuable limnological tool for establishing sediment chronologies for the lake sediments in china.

关键词： lake sediment radionuclide dating method.

Spacial organization on the rural settlements in plain areas—taking Pinghu city in Zhejiang of china as an example

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Journal of Geographical Sciences 2000年第3期10卷 59-64页

作者： XUE Dong-qian1, YAO Shi-mou2. ZHANG Hong1 (1. Dept. of Tourism and Environment, Shaanxi Normal University, Xi’an 710062. china 2. {4. {2. of geography and {4., Chinese Academy of Sciences, nanjing 210008, china)

This paper analyses the spacial distribution, quantity-scale, function-structure and facilities from the angle of spacial organizational optimizing theory and sustainable development thought. The authors point out the distributional principles of rural settlements in plain areas, and put forward planning and distribution of various levels of rural settlements (central villages, basic villages and natural villages).

关键词： plain area central villages basic villages natural villages spacial organization

Effect of sediment resuspension on underwater light field in shallow lakes in the middle and lower reaches of the Yangtze River:A case study in Longgan Lake and Taihu Lake

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Science china Earth Sciences 2006年第z1期49卷 114-125页

作者： ZHANG Yunlin, QIN Boqiang, ZHU Guangwei, GAO Guang, LUO Liancong & CHEN Weimin nanjing institute of {2. & limnology, Chinese Academy of Sciences,{4., china Graduate School of Chinese Academy of Sciences, Beijing 100039, china 1. nanjing institute of {2. & limnology Chinese Academy of Sciences Nanjing 210008 China 2. Graduate School of Chinese Academy of Sciences Beijing 100039 China

Based on three continuous in situ underwater light field measurement under different wind waves conditions in Longgan Lake, Meiliang Bay of Taihu Lake in July 2.03 and littoral zone near TLLER in July 2.04. respectively, the effects of sediment resuspension caused by wind waves on PAR diffuse attenuation, absorption coefficients and euphotic depths are analyzed. In Longgan Lake, PAR diffuse attenuation coefficients during small, middle and large wind waves were 1.74. 2.02.and 2.4. m-1, respectively, and the corresponding PAR spectral diffuse attenuations ranged from 0.98 to 2.97, 1.34.to 3.95 and 1.80 to 5.4. m-1, respectively. In Meiliang Bay, PAR diffuse attenuation coefficients were 2.63, 3.72. 4.37 m-1 during small, middle and large wind waves. PAR diffuse attenuation coefficients increased by 4.% and 66% from small to middle, large wind waves, respectively. Absorption coefficients integrated over the range of PAR of CDOM, phytoplankton were 0.2., 0.2. m-1; 0.76, 0.4. m-1, respectively during middle and large wind waves. Absorption coefficients integrated over the range of PAR of non-algal particulate matter and total suspended particulate matter increased from 0.94.to 1.73 m-1, and from 1.70 to 2.2. m-1, respectively during middle and large wind waves. Relative contributions of absorption coefficients of non-algal particulate matter to total absorption coefficient integrated over the range of PAR were 4..14., 65.05%, respectively, during middle and large wind waves. PAR euphotic depths decreased by 0.4., 0.19, 0.2. m from middle to large wind waves in Longganhu Lake, Meliang Bay and littoral zone near TLLER. Significant correlations were found between transparency, PAR diffuse attenuation coefficients, euphotic depths and total suspended paniculate matter, wind velocity, wave height. Most significant correlations were found between transparency, PAR diffuse attenuation coefficients, euphotic depths and inorganic suspended paniculate matter but low correlations

关键词： shallow lake, Taihu Lake, diffuse attenuation coefficient, absorption coefficient, total suspended particulate matter.

Multiple Effects of Energy Issues and Countermeasures: A Case of Shandong Province

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Chinese Journal of Population,Resources and Environment 2008年第4期6卷 88-94页

作者： Wang Chengxin1,2., Wang Gefang3 , Yao Shimou4.1. College of Population, Resources and Environment, Shandong Normal University, Jinan Shandong 2.0014. china 2. Research Center of Cycle Economy of Shandong Province, Jinan Shandong 2.0001, china 3. Party School of the Shandong Committee of CPC, Jinan Shandong 2.002., china 4. nanjing {4. of geography and limnology, Chinese Academy of Sciences, nanjing Jiangsu {14., china College of Population Resources and Environment Shandong Normal University Research Center of Cycle Economy of Shandong Province Party School of the Shandong Committee of CPC nanjing institute of {2. and limnology Chinese Academy of Sciences

Energy is now becoming the bottleneck of urban and regional development. The paper takes Shandong Province, one of the most energy consuming provinces in china, as an example, uses quantity methods such as SPSS (Stastics Package for Social Science) cluster sampling and regression analysis, and applies quantity analysis, to analyze the situation of energy issues in Shandong province. The conflicts between the quick industrialization and increasing extensive economic development, between urban population and energy consuming per head, between the infinite energy consuming desire and the low level of managing system, and between the unstable world energy supply and the limited energy storage in china are the main factors of energy crisis in Shandong, which not only results in energy shortage, but also becomes the barrier of economic and social development. In order to ensure sufficient energy supply for Shandong province in the 2.st century, we should take countermeasures, such as changing the economic development model, pursuing a multiple and high quality energy strategy, improving the intensive urbanization strategy, and building a scientific energy system.

关键词： energy effects countermeasure Shandong Province

Simulation　of　sludge－dredging　effects　in　controlling　nutrient　release　of　LakeKasumigaura　with　large－size　core　samples

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Journal of Environmental Sciences 1996年第4期8卷 385-389页

作者： Fan Chengxin (nanjing institute of {2. and limnology, Chinese Academy of Sciences,nanjing 210008,china) Morihiro AIZAKI Kunio KOHATA(The National institute for Environmental Studies, Tsukuba), Japan nanjing Inst. Geogr. and limnology Chinese Academy of Sciences Nanjing 210008 China Natl. Inst. for Environ. Studies Tsukuba Japan

Nutrient release from the dredged and undredged sediments in Lake Kasumigaura were simulated under the laboratory control conditions with large-size core samples. It was found that phosphate and ammonia release fluxes are less in aerobic than those in anaerobic. In different simulated dredged depth, the phosphate release showed large divergence in the anaerobic than in the aerobic. There was a larger accumulated release of phosphate and ammonia at actual dredged (St. B) than the undredged (St. A) in anaerobic condition. This showed that the sludge-dredging was effective of controlling phosphorus and nitrogen release. A preliminary assessment is drawn from the experiments that the sludge-dredging work in Tsuchiura Bay of Lake Kasumigaura can reduce about 15. 9% of phospbate and 56. 2. of anunonia release from the sediments respectively.

关键词： sludge-dredging nutrient release aerobic and anaerobic conditions core samples Lake Kasumigaura.

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 {2. and limnology, Chinese Academy of Sciences,{4., 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 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 14., 2.0Pb and 137Cs dating are mainly used to establish the chronology for recent several ten thousand years. Because of being mixed with “dead carbon”, the measured 14. 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. 2.0Pb 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 14. dating is stronger. Based on the analysis on results of 14., 2.0Pb and 137Cs of the lacustrine sediments from Co Ngoin, central Tibetan Plateau, we use the simple regression method to re-calculate the 14. calendar ages, and establish the time sequence for cores CE-1 and CE-2.with result of 2.0Pb CRS model for the upper 35 cm and re-calculated 14. calendar age for sediments bellow 35 cm. Since 14.0 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： 14., 2.0Pb and 137Cs, chronology, lacustrine sediments, climatic event, Co Ngoin, central Tibetan Plateau.

Study on the simulation of transparency of Lake Taihu under different hydrodynamic conditions

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Science china Earth Sciences 2006年第z1期49卷 162-175页

作者： PANG Yong, LI Yiping & LUO Liancong College of Environmental Science and Engineering, Hohai University, nanjing 2.0098, china nanjing {4. of {4. & limnology, Chinese Academy of Sciences, nanjing 2.0098, china Hohai Univ Coll Environm Sci & Engn Nanjing 210098 Peoples R China Chinese Acad Sci Nanjing Inst Geog & Limnol Nanjing 210098 Peoples R China

It was indicated in this study that there were negative relations between the concentrations of suspended solid (SS) and transparency according to the analysis of measured data of Lake Taihu. Their relations in pervious studies were reviewed, which showed that the changes of transparency in Lake Taihu could be reflected by simulating suspended solid concentration (SSC). Measured data showed that the changes of SSC with wind speed were similar at different water *** increased with the increasing of wind speed. Both wave and lake current of Lake Taihu had positive relations with SSC. However, wave was the main factor affecting sediment suspension, while flow took the second place. In this study, a numerical model coupling lake current, wave and SSC of Lake Taihu was developed. In the SS model, the combined effects of wave and current were *** amounts of suspended and deposited sediments near the lake bed surface layer were treated separately. The stochastic characteristics of turbulent flow pulsation near lake beds were also considered, and the start-up conditions of sediment suspension were introduced to the model. The model elucidated the mutual exchange processes between sediment particles in SS and active sediments within and on the bed surface layer. Simulated results showed that lake current had relatively significant effects on the SSC at littoral areas of Lake Taihu, while SSC at the central area of the lake was mainly influenced by wave. The changes of transparency with SSC were simulated for Lake Taihu using this model. Calculated results were validated by measured data with good fitness, which indicated that the model is basically suitable for the simulation and prediction of transparency of Lake Taihu.

关键词： transparency suspended solid hydrodynamlc sediment suspension model.