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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 geography & limnology, chinese academy of sciences, nanjing 210008, china 2. The Key Laboratory of Industrial Biotechnology, Ministry of Educa- tion, Southern Yangtze University, Wuxi 214036, china 3. School of Biotechnology, Southern Yangtze University, Wuxi 214036, china nanjing institute of geography & 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

Late Jurassic and Early Cretaceous Radiolarians from Zhilong,Gyangse,Tibet

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地学前缘 2009年第S1期16卷 275-276页

作者： Bo Xu,Hui Luo nanjing institute of Geology and Palaeontology,chinese academy of sciences,nanjing 210008,china.

Abundant well-preserved Late Jurassic-Early Cretaceous radiolarian fossils were extracted from 31 bedded green chert samples collected from Zhilong section,Gyangse,southern ***

关键词： Late Jurassic Early Cretaceous radiolarians Zhilong Gyangse Tibet

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 geography & 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.

Numerical simulation of Meiyu front and the diagnosis of moist vorticity vector

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Progress in Natural Science:Materials International 2007年第11期17卷 1341-1347页

作者： Ping Fan1,2 and Luo Zhexian2(1. institute of Atmospheric Physics, chinese academy of sciences, Beijing 100029, china 2. nanjing University of Information sciences & Technology, nanjing 210044, china) institute of Atmospheric Physics Chinese Academy of Sciences Beijing 100029 China nanjing University of Information sciences & Technology Nanjing 210044 China

Moist vorticity vector is introduced to study the development and evolution of mesoscale convective vortex (MCV) in the Meiyu front precipitation with the Advanced Regional Predication System (ARPS). In this study, the heavy rainfall is simulated to investigate the genesis, development and dissipation of middle scale convective vortex, which occurred from 0000 UTC 3 July to 1200 UTC 5 July over the Jianghuai River valley. Moist vorticity vector (MVV) has zonal, radial and vertical components in its 3D spatial distribution. The simulation shows that the vertical component of moist vorticity vector well demonstrates the spatial distribution characteristics of middle scale convective vortex, especially in the process of Meiyu front precipitation. Diagnosis upon zonal, radial averaged and mass-integrated quantities of MVV shows that its vertical component and the surface precipitating ratio are in phase with a correlation coefficient of 0.68, indicating that the vertical component of MVV is closely associated with the Meiyu front precipitation. In addition, the tendency of the vertical component of MVV is mainly determined by the interaction between the vorticity and the zonal and radial gradient of condensational or depositional heating.

关键词： moist vorticity vector mesoscale convective vortex Meiyu front precipitation

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 institute of Meteorology, nanjing 210044, china 2. institute 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.

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 geography 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.: 86-25-86882140 Fax: 86-25-57713063.

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.

Influence of Neutral Salts and pH on Exchangeable Acidity of Red Soil and Latosol Colloids

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Pedosphere 2002年第1期12卷 81-88页

作者： ZHOU SHIWEI, ZHANG GANGYA and ZHANG XIAONIAN institute of Soil Science, the chinese academy of sciences, nanjing 210008 (china) institute of Soil Science the Chinese Academy of Sciences Nanjing 210008

In the present work, the exchangeable acidity of a red soilcolloid and a latosol colloid at different pH during reacting withfour neutral salts was measured. The results show that theexchangeable acidity increased with increasing amounts of the neutralsalts added, and the relation between them was almost linear. Whenthe amount of the neutral salt added was lower than a certain value,the slop of the line was high, and the slop turned low when theamount exceeded that value, so there was a turning point in eachline. The addition amounts of the neutral salts for the turningpoints were affected by the cation species of the neutral salts, butpH had less effect on them. After the turning points occurred, theexchangeable acidity of the red soil colloid still graduallyincreased with the addition amounts of the neutral salts, but that ofthe latosol colloid did not increase any more.

关键词： exchangeable acidity latosol neutral salt pH

Exchange Reaction Between Selenite and Hydroxyl Ion of Variable Charge Soil Surfaces: I. Electrolyte Species and pH Effects

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Pedosphere 2003年第4期13卷 227-232页

作者： ZHOU SHIWEI, ZHANG GANGYA and ZHANG XIAONIANinstitute of Soil Science, the chinese academy of sciences, nanjing 210008 (china) institute of Soil Science the Chinese Academy of Sciences Nanjing 210008

Hydroxyl release of red soil and latosol surfaces was quantitatively measuredusing a self-made constant pH automated titration instrument, to study the changes of hydroxylrelease with different added selenite amounts and pH levels, and to study the effects ofelectrolytes on hydroxyl release. Hydroxyl release increased with the selenite concentration, with arapid increase at a low selenite concentration while slowing down at a high concentration. The pHwhere maximum of hydroxyl release appeared was not constant, shifting to a lower valus withincreasing selenite concentration. Hydroxyl release decreased with increasing electrolyteconcentration, and the decrease was very rapid at a low electrolyte concentration but slow at a highelectrolyte concentration. For NaClO_4, NaCl and Na_2SO_4, hydroxyl release was in the order ofNaClO_4 > NaCl >> Na_2SO_4, and the difference was very significant. But for NaCl, KCl and CaCl_2,the order of hydroxyl release was NaCl > KCl > CaCl_2, and the difference was smaller. The amount ofhydroxyl release from Xuwen latosol was greater than that from Jinxian red soil. Hydroxyl releaseexisted in a wider range of pH with Xuwen latosol than with Jinxian red soil, due to theirdifference in soil properties. However, both soils had similar curves of hydroxyl release,indicating the common characteristics of variable charge soils.

关键词： hydroxyl release ion exchange reaction selenite adsorption variable chargesoils

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Numerical Simulation of Preferential Flow of Contaminants in Soil

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Pedosphere 2001年第2期11卷 131-136页

作者： XU SHAOHUI, DU ENHAO and ZHANG JIABAO institute of Soil Science, the chinese academy of sciences, nanjing 210008 (china) 中科院南京土壤所江苏南京 210008

A simple modeling approach was suggested to simulate preferential transport of water and contaminants in soil. After saturated hydraulic conductivity was interpolated by means of Krige interpolation method or scaling method, and then zoned, the locations where saturated hydraulic conductivity was larger represented regions where preferential flow occurred, because heterogeneity of soil, one of the mechanisms resulting in preferential flow, could be reflected through the difference in saturated hydraulic conductivity. The modeling approach was validated through numerical simulation of contaminant transport in a two-dimensional hypothetical soil profile. The results of the numerical simulation showed that the approach suggested in this study was feasible.

关键词： contaminant numerical simulation preferential flow soil