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Application of Equilibrium Partitioning Approach to the Derivation of Sediment Quality Guidelines for Metals in Dianchi Lake

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Pedosphere 2007年第3期17卷 284-294页

作者： CHEN Yun-Zeng YANG Hao ZHANG Zhen-Ke QIN Ming-Zhou JIN Feng LU Jun-Jie institute of Resources and Environment Henan University Kaifeng 475001 （China） State Key Laboratory of Soil and Sustainable Agriculture Institute of Soil Science Chinese Academy of SciencesNanjing 210008 （China） College of geography Nanjing Normal University Nanjing 210097 （China） Key Laboratory of Coast and Island Development of MOE Nanjing University Nanjing 210093 （China）

For the past 20 years, numerous studies have been carried out on the application of equilibrium partitioning approach （EqPA） for the derivation of sediment quality guidelines （SQGs）. However, for metals, few Equilibrium-partitioning- based numerical SQGs have been developed or are currently available because of the confounding factors mediating the bioavailability of metals. A study was conducted at Dianchi Lake, which is a heavily eutrophicated lake on the Yunnan- Guizhou Plateau, china with the focus on the measurement of partitioning coefficient （Kp） and SQGs derivation and normalization to acid volatile sulfide （AVS）, fine material, and organic carbon. Using new normalization methods, SQGs were formulated for seven metals including copper, zinc, lead, cadmium, chromium, mercury, and arsenic in Dianchi Lake. In Dianchi Lake sediments, the fine material contributed 25.4.-3..0% to the SQG values, with the largest contribution to the SQG value of mercury; AVS contributed 2.9%-75.0% to the SQG values, with the largest contribution to the SQG value of cadmium. This indicated that the fine material and the AVS were the most important controlling factors to the bioavailability of mercury and caximium, respectively. The contribution of total organic carbon （TOC） to the SQG values of copper and leaxi was 3.8% and 7.1%, respectively, indicating that at relatively lower concentrations, the contribution of TOC was not significant. In addition to normalization methods, appropriate procedures for the application of EqPA including sample collection, storage, and analysis are also essential to improve the reliability of SQGs. The normalized Dianchi Lake SQGs were higher than most of the empirically based SQGs developed in North America, but lower than Hong Kong interim SQGs except for cadmium and arsenic. The differences could be attributed to the approaches used for derivation of SQGs and the water quality criteria adopted and the differences in the physical and chemical charac

关键词： acid volatile sulfide fine material normalization method organic carbon sediment quality guidelines

Fractionation of Heavy Metals in Sediments from Dianchi Lake,china

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Pedosphere 2007年第2期17卷 265-272页

作者： LI Ren-Ying YANG Hao ZHOU Zhi-Gao Lü Jun-Jie SHAO Xiao-Hua JIN Feng State Key Laboratory of Soil and Sustainable Agriculture Institute of Soil Science Chinese Academy of Sciences Nanjing 210008 （China）. College of geography Science Nanjing Normal University Nanjing 210097 （China） Department of Applied Meteorology Nanjing University of Information Science ＆ Technology Nanjing 210044 （China）

Fractionation of heavy metals in sediments can help in understanding potential hazards of heavy metals. The present study analyzed total concentrations and fractions of selected heavy metals （Cd, Cr, Cu, Pb, and Zn） in surface sediments from Dianchi Lake, Yunnan Province, china, as well as factors that may affect distributions of the various heavy metal fractions. Total concentrations of the heavy metals decreased in the order Zn 〉 Cu 〉 Pb 〉 Cr 〉 Cd. These heavy metals, except Cr, were much higher than their background levels, indicating that Dianchi Lake was polluted by Cd, Zn, Pb, and Cu. Cadmium occurred mainly as the non-residual fraction （sum of the HOAc-soluble, reducible, and oxidizable fractions）（97.6%）, and Zn （55.7%） was also predominantly found in the non-residual fraction. In contrast, most of the Cr （88.5%）, Pb （81.8%）, and Cu （59.2%） occurred in the residual fraction. Correlation analysis showed that total heavy metal concentrations, organic matter and reducible Fe were the main factors affecting the distributions of the various heavy metal fractions. In the Walhai section of Dianchi Lake （comprising 97% of the lake area）, the concentrations of Cd, Zn, Pb, and Cu in the non-residual fraction were significantly lower （P ≤ 0.01 or 0.05） than those of the Caohal section （3. of the lake area）. This indicated that potential heavy metal hazards in the Caohai section were greater than the Waihai section.

关键词： Dianchi Lake heavy metal fractions lake sediment organic matter reducible Fe

SOME KEY PROJECTS FOR THE SUSTAINABLE DEVELOPMENT OF THE YANGTZE CORRIDOR

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Bulletin of the Chinese academy of sciences 1996年第3期10卷 207-214页

作者： Yu Xiaogan & Chen Wen(nanjing institute of geography and {3., CAS)

The Yangtze Valley is expected to become the largest industrial corridor in the world and additionally home to a cluster of inland harbours and urbanized belts thanks to its highly favorable conditions that encourage rapid economic development. In order to realize this spectacular goal, it is imperative to introduce a lot of key infrastructure projects for energy, transport, grain production and eco-environment protection for the Valley’s sustainable development.

关键词： SOME KEY PROJECTS FOR THE SUSTAINABLE DEVELOPMENT OF THE YANGTZE CORRIDOR

Palaeoclimate simulation of Little Ice Age

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Progress in Natural Science:Materials International 2004年第8期 68-76页

作者： LIU Jian 1, CHEN Xing 2, WANG Sumin 1 and ZHENG Yiqun 1 (1. nanjing institute of geography and {3., Chinese {4. of sciences, nanjing 2.0008, china 2. Department of Atmospheric Science, nanjing University, nanjing 210093. china) nanjing institute of geography and {3. Chinese Academy of Sciences Nanjing 210008 China Department of Atmospheric Science Nanjing University Nanjing 210093 China

Little Ice Age (LIA) is a typical cold climate period in global scope with a profound impact upon human society. In this study, a coupled global atmospheric circulation model including the land processes (AGCM + SSiB) is used to perform the simulation of LIA climate. Under the control of solar radiation reduction mechanism, the decrease of temperature is more obvious in summer than in winter; meanwhile, there is regional difference in the change of winter temperature. But the temperature decrease is the main characteristic of the annual mean temperature. Volcanic dust has an evident effect on the winter temperature decrease, but to a less extent than the solar radiation. The synchronous function caused by the reduction of solar radiation and the increase of optic depth of volcanic dust has a superposed strengthening effect on the temperature decrease in large regions. Promotion of the vegetation cover rate profits the increase of temperature, and vise versa. Certain decrease of solar radiation will favor the increase of summer monsoon precipitation in East Asia. The increase of optic depth of volcanic dust does not have a significant effect on the annual precipitation in most parts of Eurasian continent. The composite effect of the decrease of solar radiation and the increase of volcanic dust makes the summer monsoon precipitation in East china increase, and that in South Asia decrease. Together with vegetation change, the result shows that precipitation increases with the increase of vegetation coverage (e.g. East Asia), and when the vegetation coverage reduces (e.g. North Africa) the precipitation will decrease, too.

关键词： Little Ice Age model simulation East Asia.

Sensitivity Assessment for Soil Hydraulic Conductivity in a Coupled Surface-Subsurface Water Flow Model

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Sensitivity Assessment for Soil Hydraulic Conductivity in a ...

Surface pollen and vegetation reconstruction from central and northern mountains of Taiwan

水资源管理与工程国际学术会议

作者： Qi ZHANG State Key Laboratory of Lake Science and Environment nanjing institute of geography and {3..Chinese {4. of sciences nanjing.2.0008.china

＜正＞For coupled surface-subsurface water flow modeling,the soil layer is an important domain since it affects both the generation of surface runoff and water flux between surface and groundwater *** is a need to assess how the soil physical parameters affect the modeling results to help guide field measurements and model parameter *** paper investigates the sensitivity of the modeling results in response to the soil hydraulic conductivity by performing a surface-subsurface water flow simulation for a sub catchment of Lake *** indicate that soil lateral flow and groundwater recharge are the most sensitive flow components to the change of soil hydraulic *** increase in soil hydraulic conductivity results in an increase in these *** increase in groundwater recharge consequently causes the rise of groundwater table for the catchment,which induces more groundwater discharge to rivers as base *** is worthy to note that a change of soil hydraulic conductivity less than 3.%does not cause a noticeable change in flow components. It is also interesting to notice that the model prediction accuracy of river discharge is not sensitive to the change of soil hydraulic conductivity,which implies that assessment of simulation accuracy and model validation using river discharge solely may not be sufficient for a surface-subsurface water flow simulation. Internal flow components are important and essential to use for a more reliable model validation.

关键词： Soil hydraulic conductivity sensitivity seeseement base flow groundwater recharge soil lateral flow coupled hydrological modeling WATLAC

来源： cnki会议评论

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cnki会议

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Chinese Science Bulletin 2003年第3期48卷 291-295页

作者： YU Ge1, LIEW Pingmei2, XUE Bin1 & LI Zhengyi2 1. nanjing institute of geography & Limnolog of the Chinese Academof {3.,{4., china 2. Department of Geology, Taiwan University, Taibei 106-17, Taiwan, china nanjing institute of geography & Limnolog of the Chinese {3. of {4. Nanjing 210008 China

Surface pollen from various montane vegeta-tions in Shalixian Mt. and Lepei Mt. of central and northern Taiwan have been explored and analyzed. The pollen datawere used to simulate vegetation types by using the biomisa-tion technique. Computing three matrixes of pollen taxa,plant functional types and combined biomes, vegetation types at each site have been finally defined through the fuzselections of a tie-breaking rule. The results show that sur-face pollen data can simulate the subtropical Castanopsis andCyclobalanopsis forests, alpine warm-temperate Quercus and Quercus-Pinus forests, and alpine temperate/cool-temperate conifers of Tsuga-Picea and Picea-Abies forests. Simulatedelevations of the forests are similar to actual locations of the forests. This study can add vertical surface pollen data forextending investigation of various vegetation types in china, provide PFT schemes and vegetation types in low-latitude and montane areas, and be applied as modern analogues for fossil pollen in order to reconstruct Quaternary

关键词：台湾省北部山区中部山区表层花粉植被重建植被类型

CLIMATIC VARIATIONS IN china OVER THE LAST 2000 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 73.000, P.R.{3. 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 limnology 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 2000 years. For all-china temperature reconstruction, six sub-stages are identified for the last two millennia. Around AD 0－24., AD 800－1100, AD 13.0－14.0 and the period from AD 1880 on were warm while around AD 24.－800, AD 1100－13.0, AD 14.0－1880 were cold. Also, temperature varied from region to region in each of the warm or cold periods. The Eastern Han warm period (0－AD 24.), 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 1150－14.0. 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

Fractionations of rare earth elements in plants and their conceptive model

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Science china(Life sciences) 2007年第1期50卷 47-55页

作者： DING ShiMing1,2, LIANG Tao2, YAN JunCai3. ZHANG ZiLi3. HUANG ZeChun2 & XIE YaNing4.1 nanjing institute of {4. & {3., Chinese academy of sciences, nanjing 2.0008, china 2 institute of Geographic sciences and Natural Resources Research, Chinese academy of sciences, Beijing 100101, china 3.Anhui Agricultural University, Hefei 23.03., china 4.State Key Laboratory of Synchrotron Radiation, institute of High Energy Physics, Chinese academy of sciences, Beijing 10003., china 1. nanjing institute of geography & {3. Chinese Academy of Sciences Nanjing 210008 China 2. institute of Geographic sciences and Natural Resources Research Chinese Academy of Sciences Beijing 100101 China 3. Anhui Agricultural University Hefei 230036 China 4. State Key Laboratory of Synchrotron Radiation Institute of High Energy Physics Chinese Academy of Sciences Beijing 100039 China

Fractionations of rare earth elements (REEs) and their mechanisms in soybean were studied through application of exogenous mixed REEs under hydroponic conditions. Significant enrichment of middle REEs (MREEs) and heavy REEs (HREEs) was observed in plant roots and leaves respectively, with slight fractionation between light REEs (LREEs) and HREEs in stems. Moreover, the tetrad effect was observed in these organs. Investigations into REE speciation in roots and in the xylem sap using X-ray absorption spectroscopy (XAS) and nanometer-sized TiO2 adsorption techniques, associated with other controlled experiments, demonstrated that REE fractionations should be dominated by fixation mechanism in roots caused by cell wall absorption and phosphate precipitation, and by the combined effects of fixation mechanism and transport mechanism in aboveground parts caused by solution complexation by intrinsic organic ligands. A conceptive model was established for REE fractionations in plants based on the above studies.

关键词： rare earth elements (REEs) fractionation tetrad effect plant accumulation X-ray absorption spectroscopy (XAS) nanometer-sized TiO2

Pollen and Phytolith Analyses of Ancient Paddy Fields at Chuodun Site, the Yangtze River Delta

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Pedosphere 2007年第2期17卷 209-218页

作者： LI Chun-Hai ZHANG Gang-Ya YANG Lin-Zhang LIN Xian-Gui HU Zheng-Yi DONG Yuan-Hua CAO Zhi-Hong ZHENG Yun-Fei DING Jin-Long nanjing institute of geography and {3. Chinese Academy of Sciences Nanjing 210008 （China） institute of Soil Science Chinese Academy of Sciences Nanjing 210008 （China） Zhejiang Provincial institute of Cultural Relics and Archaeology Hangzhou 310014 （China） Suzhou Museum Suzhou 215001 （China）

A number of paddy fields pertaining to the Majiabang Cultures (5500-3.00 years BC) were discovered during the archaeological excavations that were carried out since 1998 at the Chuodun site in the Yangtze River Delta. The pollen and phytolith analyses of two soil profiles from the northeastern part of this site were carried out to trace the agricultural practices of the Neolithic period. The phytolith results showed that rice domestication in the Yangtze River Delta could be traced back to as early as the Majiabang Culture. The pollen assemblage also revealed low levels of aquatic species, similar to that in modern paddy fields. This finding suggested that humans might have removed weeds for rice cultivation during the Neolithic period. Thus, pollen analysis in association with phytolith analysis was a promising method for identifying ancient paddy fields.

关键词： ancient paddy fields Neolithic period pollen analysis phytolith analysis Yangtze River Delta