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Identification of Greigite in the Pliocene Sediments of Qinghai lake and Its Geological Significance

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Acta Geologica Sinica(English Edition) 2016年第6期90卷 2261-2262页

作者： FU Chaofeng Jan BLOEMENDAL QIANG Xiaoke Mimi J.HILL AN Zhisheng Key Laboratory of Western Mineral Resources and Geological Engineering Ministry of Education of ChinaChang'an University State Key Laboratory of Loess and Quaternary Geology Institute of Earth and EnvironmentCAS Geomagnetism Lab School of Environmental SciencesUniversity of Liverpool

The Qinghai lake in North China is the largest interior plateau lake in Central Asia, and is sensitive to climate change and the environmental effects of Tibetan Plateau uplift. An almost continuous 626 m long sedimen... 详细信息

关键词： In lake Identification of Greigite in the Pliocene Sediments of Qinghai lake and Its Geological Significance

RELATIVE BRIGHTNESS INDEX AND IT’S CLIMATIC SIGNIFICANCE FROM LACUSTRINE SEDIM ENT OF NAPAHAI lake,NORTHWESTERN YUNNAN PLATEAU,CHINA

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Chinese Geographical Science 2002年第3期12卷 58-62页

作者： Yin, Yong Fang, Nian-qiao Hu, Chao-yong Nie, Hao-gang Qing, Zun-li The Key Laboratory of Coast & Island Development Nanjing University Nanjing P. R. China China University of Geosciences Beijing P. R. China China University of Geosciences Wuhan P. R. China

Information on the palaeoenvironm ent from Late Pleistocene to Holocen e in northwestern Yannan Plateau has been deduced from a study of a 28.81m-long core taken from Napahai *** results from Relative Brightness In-dex(RBI )as well as those from the lithological analyses of bulk sediments,total organic carbon and granulometric analy-ses have been used to reconstruct the environmental and climatic evoluti on of the *** ages were provided by three 14 C *** record suggested a climate fluctuation between warm-dry a nd cool-wet from ca.57to 32ka B.P.,which led a shallowing and swamping of the l *** water level again increased quickly at ca.32ka B.P.,reached it’ s peak during LGM(Last Glacial Maximum,ca.18-20ka B.P.)and remained relative high until ca.15ka *** high wa-ter level at LGM is attributed to cold-wet *** area experienced an abrupt and unstable climatic ch anges dur-ing the transition period from15to 10ka *** a dominated littoral en ***-dry climate led to the contrac-tion of the lake during the Holocene a nd reed-swamps became *** a minor wet-cool pulse during the L ate Holocene,the modern climate became to be established.

关键词： Relative Brightress Index total organic carbon particle size palaeoclimate Napahai lake

A 16000-year pollen record of Qinghai lake and its paleoclimate and paleoenvironment

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Chinese Science Bulletin 2002年第22期47卷 1931-1936页

作者： LIU Xingqi SHEN Ji WANG Sumin YANG Xiangdong TONG Guobang ZHANG Enlou Key Laboratory of lake Sedimentation and Environment Nanjing Institute of Geography and LimnologyChinese Academy of SciencesNanjing 210008China Institute of Hydrological and Environmental Geology Chinese Academy of Geological SciencesZhengding 050803China

The paleoclimate and paleoenvironment of Qinghai lake indicated by a 16000-year pollen record are as follows. It was very cold and dry before 15200 years. During the Late Glacial, the climate varied from colder and semiarid to cool and semi-humid and fluctuated frequently but with little amplitude. Three cold events in the periods of 13400-13000, 11600-12000, and 11000-10400 aBP respectively correspond to the Oldest Dryas, Older Dryas and Younger Dryas events, whereas the two warm periods between them, 12000-13000 and 11600-11000 aBP, respectively correspond to Boiling and Allerod periods. The temperature increased abruptly after the Younger Dryas event, and then the climate gradually turned to be warm and wet from warm and semiarid. In the Holocene, the largest amplitude of cold event that occurred at ca. 8200 aBP is quite prominent. The Holocene climatic optimum culminated at 6700 aBP. After 2100 aBP, the climate tended to be cold and dry, keeping on up to now. Palaeoclimatic evolution and events of

关键词： Qinghai lake pollen Lateglacial paleoclimate and paleoenvironment.

Evaluation of the WRF-lake Model over Two Major Freshwater lakes in China

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Journal of Meteorological Research 2019年第2期33卷 219-235页

作者： Yuanyuan MA Yi YANG Chongjian QIU Chenghai WANG Key Laboratory for Semi-Arid Climate Change of the Ministry of Education College of Atmospheric SciencesLanzhou University Key Laboratory of Land Surface Process and Climate Change in Cold and Arid Regions Northwest Institute of Eco-Environment and Resources Chinese Academy of Sciences

This paper evaluates the performance of the Weather Research and Forecasting(WRF) model coupled with a lake scheme over the lake Poyang and lake Dongting regions. We choose several cases with different weather characteristics, including winter with/without precipitation and summer with/without precipitation, and conduct a series of experiments(without the lake model, with the default lake model, and with a calibrated lake model that adjusts the water absorption, extinction coefficients, and surface roughness length) for each case. The results show that the performance of the lake model is significantly affected by the weather conditions. For the winter with precipitation cases, the performance of the default lake model is even worse than without the lake model, but the calibrated lake model can obviously reduce the biases of 2-m temperature and dew-point temperature. Although the performance of the default and new calibrated models is intricate for other cases, the new calibrated model has prominent advantages for 2-m dew-point temperature. Moreover, a long-term simulation of five months also shows that the new calibrated coupled lake model performs better than the default one. These imply that the new calibrated coupled lake model is more suitable to be used in studies of the effects of lake Poyang and lake Dongting on regional weather and climate.

关键词： atmosphere-lake coupled model lake Poyang lake Dongting calibration weather characteristics

The Factors for Transformation between the Fractions of Speciation of Trace Metals in lake Sediments

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Acta Geologica Sinica(English Edition) 2017年第2期91卷 753-754页

作者： ZHANG Hui School of Environmental Science and Engineering Shanghai Jiaotong UniversityShanghai 200240China

Objective Despite the fact that the bioavailability of trace metals indicated by their speciation has been an indispensable parameter in the assessment and treatment of the environmental pollution of trace metals, many studies have suggested that the bioavailability of trace metals may change according to the conditions of the environment, and the speciation of trace metals can also transform between some fractions. These transformations are related with these factors such as the compositions, microorganism, time, and other physical-chemical conditions of the system. Our work aims to systematically investigate and probe the factors to affect the transformation aside from analysis at certain time-place. The results of these understanding and investigations can be used for reasonably determining the allocation of financial and technical resources in natural and engineered processes, with bringing about inspirations from the evolution of the speciation of the trace metals on environmental impacts.

关键词： The Factors for Transformation between the Fractions of Speciation of Trace Metals in lake Sediments lake

lake records and LGM climate in China

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Chinese Science Bulletin 2000年第13期45卷 1158-1164页

作者： Ge Yu Bin Xue Sumin Wang Jian Liu Nanjing Inst Geog & Limnol Nanjing 210008 Peoples R China

Chinese lake status database has provided systematic geological records of much higher lake level and fresher water than today at the LGM from western China. This wet condition was significant contrast with very dry conditions in eastern China. Together with lake studies from Eurasian continents, there was a wet-condition belt from the Mediterranean and the Middle East, Central Asia to western China. Palaeoclimate simulations confirmed that the wet conditions in western China were produced by decrease of the evaporation and increase of precipitation by positive anomaly of annual P-E of 70-95 mm/a between the LGM and today. The westerlies enhanced in the strength and shifted southwards-eastwards in the position, and the low thermal conditions in the Eurasian continent creating temperature 4-16℃ lower than today and relatively low evaporation, were the major two important climate conditions to yield cold-wet climates in western China.

关键词： LGM high lake level western China precipitation and evaporation.

Numerical simulation of wind-driven circulation and pollutant transport in Taihu lake based on a quadtree grid

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Water Science and Engineering 2019年第2期12卷 108-114页

作者： Xiao-dong Liu Ling-qi Li Peng Wang Zu-lin Hua Li Gu Yuan-yuan Zhou Lu-ying Chen Key Laboratory of Integrated Regulation and Resource Development on Shallow lakes of Ministry of Education Nanjing 210098China College of Environment Hohai UniversityNanjing 210098China

In this study,a two-dimensional flow-pollutant coupled model was developed based on a quadtree *** model was established to allow the accurate simulation of wind-driven flow in a large-scale shallow lake with irregular natural boundaries when focusing on important smallscale localized flow *** quadtree grid was created by domain *** governing equations were solved using the finite volume method,and the normal fluxes of mass,momentum,and pollutants across the interface between cells were computed by means of a Godunov-type Osher *** model was employed to simulate wind-driven flow in a circular basin with non-uniform *** computed values were in agreement with analytical *** results indicate that the quadtree grid has fine local resolution and high efficiency,and is convenient for local *** is clear that the quadtree grid model is effective when applied to complex flow ***,the model was used to calculate the flow field and concentration field of Taihu lake,demonstrating its ability to predict the flow and concentration fields in an actual water area with complex geometry.

关键词： Numerical simulation Wind-driven circulation Pollutant transport Quadtree grid Shallow-flow hydrodynamics Taihu lake

Evolution model of a modern delta fed by a seasonal river in Daihai lake,North China:determined from groundpenetrating radar and trenches

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Frontiers of Earth Science 2019年第2期13卷 262-276页

作者： Beibei LIU Chengpeng TAN Xinghe YU Xin SHAN Shunli LI College of Geosciences China University of PetroleumBeijing 102249China School of Geoscience and Technology Southwest Petroleum UniversityChengdu 610500China Key Laboratory of Marine Sedimentology and Environmental Geology First Institute of OceanographyState Oceanic AdministrationQingdao 266061China School of Energy Resources China University of Geosciences (Beijing)Beijing 100083China

While deltas fed by seasonal rivers are common in modem sedimentary environments,their characteristics remain unclear as compared to those fed by perennial *** study identifies a small delta discharged by a seasonal stream flowing into Daihai lake,in northern China,which is driven by ephemeral and high-energy flood *** 3D facies architecture was analyzed using ground-penetrating radar (GPR) and sedimentary logs from outcrop and *** types of radar surfaces,including truncations of underlying inclined strata,weak reflections,and depositional surface of downlap and onlap,were *** radar facies (highangle obliquetangential,low-angle subparallel,gently plane parallel,plane-parallel,chaotic,and continuous strong reflection) were identified based on distinctive reflections,including amplitude,continuity,dip,and termination *** depositional units (Unit A to E) were documented from proximal to distal *** discharge signatures include significant grain-size decrease over short distance,abundant Froude supercritical flow sedimentary structures,poorly developed barforms,and small-scale scour and fill *** of lake-level and sediment budget were evaluated over the past 60 *** highstand stage (1960- 1980),amalgamated channel (Units A and B),and delta front (Unit C) were *** slope stage (1980-1996),the lower deposits (Units A,B,C) were eroded by Unit D with a distinct truncation *** lowstand stage,most eroded sediments bypassed the incised channel and accumulated in the distal part,in which a new depositional unit was formed (Unit E).The model demonstrates that deltas fed by seasonal rivers tend to accumulate large amounts of sediments carried by high magnitude floods within short periods.

关键词： delta evolution seasonal discharge ground-penetrating radar sedimentary architecture Daihai lake

Seasonal release of Fe and Mn at the sediment-water interface in Aha lake

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Chinese Science Bulletin 1996年第16期41卷 1359-1363页

作者：陈振楼普勇黄荣贵万国江 East China Normal University Shanghai 200062 China Institute of Geochemistry Chinese Academy of Sciences Guiyang 550002 China

The release of various harmful and poisonous elements from sediments to overlying water via pore water is one of the geochemical processes influencing and restricting the water quality of lakes. It is important for protecting and managing freshwater lakes to uncover and recognize the basic features and forming mechanism of this process.

关键词： sediment-water interface Fe-Mn, release Aha lake