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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 institute of {2. and limnology, chinese academy of sciences , nanjing 210008, china Department of {2. and Oceanology, nanjing University , nanjing 2.0093 , 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 1980s 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.

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, nanjing 210008, china Graduate School of chinese academy of sciences, Beijing 100039, china nanjing institute of {2. & limnology Chinese Academy of Sciences Nanjing China Graduate School of chinese academy of sciences Beijing 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 2.45 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 5.40 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 41% 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, 0.49 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 44.14%, 65.05%, respectively, during middle and large wind waves. PAR euphotic depths decreased by 0.40, 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.

APPLICATION　OF　GIS　IN　ANALYZING　ECOSYSTEM＇S　RELATIVE　SENSITIVITY　TO　ACID　DEPOSITION

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chinese Geographical Science 1996年第4期6卷 359-363页

作者： He Longhua Yans Hongwei(nanjing institute of {2. & limnology, the chinese academy of sciences,nanjing 210008, PRC) nanjing institute of {2. & limnology the Chinese Academy of Sciences Nanjing PRC

This paper decribo an application of GIS technology in estimating estem's relive sensitivity to acid despition. East china is selected as the research area. Four variable layers, which are ha rock, soil buffering ability, vegetation type and soil humidity, are used in the process. Five grades are separated in this research. The sensitivity mapping is also discussed in this paper.

关键词： acid deposition sensitivity index geographic information system

Temporal-spatial variations of euphotic depth of typical lake regions in Lake Taihu and its ecological environmental significance

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Science china Earth sciences 2006年第4期49卷 431-442页

作者： ZHANG Yunlin1, 2. QIN Boqiang1, HU Weiping1, WANG Sumin1, CHEN Yuwei1 & CHEN Weimin1 1. nanjing institute of {2. & limnology, chinese academy of sciences, nanjing 210008, china 2. Graduate School of the chinese academy of sciences, Beijing 100039, china nanjing institute of {2. & limnology Chinese Academy of Sciences Nanjing China Graduate School of the chinese academy of sciences Beijing China

By using the data of underwater irradiance measured in the different lakeregions of Lake Taihu during 1998—2.04 and total suspended solids (TSS), wind speeds of the total13 stations in typical lake regions during 1993—2.03, this paper analyzes the factors ofinfluencing on PAR (pho-tosynthetically available radiation) attenuation, euphotic depth, andpresents the temporal and spatial variations of euphotic depth of typical lake regions in LakeTaihu, and the spectral distributions of euphotic depth at station 2. The results show that theconcentration of TSS is the most important factor impacting PAR attenuation, followed by chlorophylla; chromophoric dissolved organic matter (CDOM) has little impact on the PAR euphotic depth. During1993—2.03, the mean yearly PAR euphotic depths of the typical lake regions ranged from 1.04 to1.95 m with a mean value of 1.35±0.2. m. The PAR euphotic depth fell into 3 spatial zone types:Type Ⅰ, the lowest, including the lake center and the inflows of rivers; Type Ⅱ, intermediate,including Meiliang Bay, Wulihu Lake and Gonghu Bay; Type Ⅲ, the greatest, including the East LakeTaihu; corresponding mean depths were approximately 1.1, 1.4, 2.0 m, respectively. The seasonalvariations of euphotic depths were not quite the same in different lake regions. In the lake center,the mean values of PAR euphotic depth in summer and autumn were significantly greater than those inwinter and spring; in the Meiliang Bay, winter means were significantly greater than in the otherthree seasons; in the East Lake Taihu, winter means were significantly less than in the other threeseasons. However, no distinct seasonal change was recorded in the Wulihu Lake, Gonghu Bay and theinflows of rivers. The spectral distributions of euphotic depth present a minimal value at the bluelight wave band of 400 nm, and a peak at the green light wave band of around 580 nm. In 1998 and1999, based on the seasonal many-day continuous measurements, the PAR euphotic depths at station 2.

关键词： lake taihu euphotic depth diffuse attenuation coefficient total suspendedsolid ecological

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, 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 Key Laboratory of Lake Sedimentation and Environment Nanjing Institute of Geography and Limnology Chinese Academy of Sciences Nanjing China institute of Tibetan Plateau Research Chinese Academy of Sciences Beijing China Graduate University of chinese academy of sciences Beijing China

Chronology is the basis for using lacustrine sediments to reconstruct the history of en-vironmental change. Radioactive-nuclides such as 14C, 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 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. 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 14C dating is stronger. Based on the analysis on results of 14C, 2.0Pb and 137Cs 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 2.0Pb CRS model for the upper 35 cm and re-calculated 14C calendar age for sediments bellow 35 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, 2.0Pb and 137Cs, chronology, lacustrine sediments, climatic event, Co Ngoin, central Tibetan Plateau.

Effects of main range and strength factors on change of COD in a shallow lake

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Journal of Environmental sciences 1998年第1期10卷 51-57页

作者： Fan Cheng xin nanjing institute of {2. and limnology,chinese academy of sciences,nanjing 210008,china

A model involving the relationship between non conservative matter (COD) and main range factors(loading, water stage) and strength factor (temperature) in a shallow lake has been established on the basis of less change of water stage area curve in certain extent, broader distribution in pollution sources and more homogeneous in quantity of heat. The effects of COD inflow and /or outflow, and hydro meterological factors upon COD content in Lake Taihu were calculated and simulated under the actual situation of the loadings and regimen. The results simulated by using the model are in better agreement with the observed field data. The error of the model was also discussed.

关键词： COD model environmental factor effects shallow lake.

Economic development and major guarantee projects in the region along the Yangtze River

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Journal of Geographical sciences 1998年第3期8卷 83-92页

作者： CHEN Wen YU Xiaogan nanjing institute of {2. & limnology, chinese academy of sciences nanjing 210008 china

The region along the Yangtze River is the major exploitation belt and a linkage of eastern and western parts of china. It plays an essential role in the national economic development. Since the implementation of the reform and open door policy, regional economy has got rapidly developed. In the process of development, the region also faces difficulties like energy shortage, backward transportation facilities, grain output reduction, and environmental deterioration. Countermeasures are put forward in the paper to cope with the difficulties.

关键词： regional economy development strategy industry transportation energy Yangtze Valley.

THE CHARACTERISTICS AND MAIN PROBLEMSOF MINORITY REGIONS IN china

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chinese Geographical Science 2001年第4期11卷 8-13页

作者： ZHANG Luo-cheng, WU Chu-cai(nanjing institute of {2. & limnology, the chinese academy of sciences, nanjing 210008, P. R. china) nanjing institute of {2. & limnology the Chinese Academy of Sciences Nanjing P. R. China

ABSTRACT: china is a country that has a large number of minorities, who live in specific regions which are mainly located in central and west china. These regions are abundant in natural resources, which are potential advantages and also an important basis for economic development in these regions. They are of general importance for china in strategic and ecological terms. They will not only affect the environment for survival of the minority regions but also affect the sustainable development of the eastern and central parts of china and even the survival and development of the chinese nation as a whole. Minorities live in relatively compact communities, among the 55 minorities, 35 of them were highly compact minorities, with a compact level of more than 90% . Here the development in infrastructure as well as social and economic development (e. g. export-oriented economy) has been and is still slow, regional poverty are most concentrated. The economic structures in minority areas are still in the low stage, which have resulted in underdevelopment in these regions.

关键词： minority regions development problems

Estimation on dynamic release of phosphorus from wind-induced suspended particulate matter in Lake Taihu

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Science china Earth sciences 2004年第8期47卷 710-719页

作者： FAN Chengxin1, ZHANG Lu1,2. QIN Boqiang1, WANG Sumin1, HU Weiping1 & ZHANG Chen1 1. Taihu Lake Laboratory for Ecosystem Research, nanjing institute of {2. & limnology, chinese academy of sciences, nanjing 210008, china 2. Graduate School of chinese academy of sciences, Beijing 100039, china Taihu Lake Lab. for Ecosystem Res. Nanjing Inst. of Geography/Limnology Chinese Academy of Sciences Nanjing 210008 China Grad. Sch. of chinese Acad. of Sci. Beijing 100039 China

Through man-made disturbance experiments, the corresponding relationships be-tween suspended particulate matter (SPM) and wind speed in different lake areas were simu-lated, the physicochemical formal transformation and biological mineralizing and decaying processes of phosphorus in SPM were studied, the contribution of phosphorus transformation to phosphorus loading of the water of Lake Taihu was quantitatively estimated. The results show that about 0.44 t·a-1 loading in Lake Taihu mainly comes from phosphorus-releasing action of SPM in physicochemical transformed to soluble reactive phosphorus (SRP), and the contribution mainly from biological mineralizing and decaying was about 42..8 t·a-1, which is equal to 15.0% of the total external loading of Lake Taihu, namely 4.7—7.5 times as much as SRP loading en-tering the lake by the rivers; thus it is the important source in dynamical internal loading of the lake. The determining factors for dynamical internal loading in lakes are organic phosphorus content in suspended solid and its biological transition availability.

关键词： phosphorus release,wind wave disturbance,particulate decaying,dynamical loading,Lake Taihu.