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Environmental archaeology of the Dachang region in the Daning Valley,the Three Gorges reservoir region of the Yangtze River,china

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Chinese Science Bulletin 2008年第S1期53卷 140-152页

作者： ZHANG Yun 1 &ZHU Cheng 2 1 State Key Laboratory of Vegetation and Environmental Change,Institute of Botany,Chinese Academy of sciences,Beijing 100093, china 2 school of geographic and oceanographic sciences,nanjing university,nanjing 210093,china State Key Laboratory of Vegetation and Environmental Change Institute of Botany Chinese Academy of Sciences Beijing China school of geographic and oceanographic sciences Nanjing University Nanjing China

Environmental archaeology of archaeological sites on both sides of the Dachang section in the Daning River,the Three Gorges of the Yangtze River,shows that riverbed evolution has a great influence on the distribution of archaeological sites during the prehistorical and historical period,and it restricts human activity and the development of ancient *** investigation,dating data,paleocurrent analysis of 100 gravels on the riverbed and archaeological excavation reveal that the riverbed of the Dachang section developed in the Shuangyantang region during the early stage,after about 30 kaBP it shifted westward gradually and reached the present *** with the westward shift,the focus of ancient culture changed for several *** the Western Zhou Dynasty's period,the east riverbank of the Daning River was the main residential *** the Han Dynasty,along with the westward shift,the living space of ancient people was no longer confined to the east riverbank and the focus of culture moved *** the Zhangjiawan site became the main dwelling *** the late Han Dynasty, the villages were flooded and the ancients had to immigrate to a high *** of the Han and the Jin Dynasties outcropped on the flood plain of the east bank because their surface sediments were eroded by several flood events and the westward shift of the riverbed.

关键词： the Daning River environmental archaeology the Shuangyantang site the Zhangjiawan site tombs of the Han and the Jin Dynasties

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Paddy Soil Stability and Mechanical Properties as Affected by Long-Term Application of Chemical Fertilizer and Animal Manure in Subtropical china

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Pedosphere 2007年第5期17卷 568-579页

作者： LI Jiang-Tao ZHANG Bin school of geographic and oceanographic sciences Nanjing University Nanjing 210093 （China） Institute of Soil Science Chinese Academy of Sciences Nanjing 210008 （China）

Wet stability, penetration resistance （PR）, and tensile strength （TS） of paddy soils under a fertilization experiment for 22 years were determined to elucidate the function of soil organic matter in paddy soil stabilization. The treatments included no fertilization （CK）, normal chemical fertilization （NPK）, double the NPK application rates （2NPK）, and NPK mixed with organic manure （NPK＋OM）. Compared with CK, Fertilization increased soil organic carbon （SOC） and soil porosity. The results of soil aggregate fragmentation degree （SAFD） showed that fast wetting by water was the key fragmentation mechanism. Among the treatments, the NPK＋OM treatment had the largest size of water-stable aggregates and greatest normal mean weight diameter （NMWD）（P ≤ 0.05）, but the lowest PR and TS in both cultivated horizon （Ap） and plow pan. The CK and 2NPK treatments were measured with PR 〉 2.0 MPa and friability index 〈 0.20, respectively, in the Ap horizon, suggesting that the soils was mechanically unfavourable to root growth and tillage. In the plow pan, the fertilization treatments had greater TS and PR than in CK. TS and PR of the tested soil aggregates were negatively correlated to SOC content and soil porosity. This study suggested that chemical fertilization could cause deterioration of mechanical properties while application of organic manure could improve soil stability and mechanical properties.

关键词： soil aggregate stability chemical fertilization organic matter penetration resistance tensile strength

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洪泽湖湿地生态脆弱性的驱动力系统与评价

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水土保持研究 2008年第6期15卷 245-249页

作者：叶正伟淮阴师范学院地理系江苏淮安223001 南京大学地理与海洋科学学院南京210093

洪泽湖湿地具有地质地貌基底性脆弱、南北气候过渡带影响的界面性脆弱、旱涝灾害频繁的波动性脆弱、生物多样性面临胁迫性的脆弱、水质污染的介入性脆弱以及人类不合理活动频繁的干扰性脆弱。AHP层次分析法评价结果显示:洪泽湖湿地的生... 详细信息

洪泽湖湿地具有地质地貌基底性脆弱、南北气候过渡带影响的界面性脆弱、旱涝灾害频繁的波动性脆弱、生物多样性面临胁迫性的脆弱、水质污染的介入性脆弱以及人类不合理活动频繁的干扰性脆弱。AHP层次分析法评价结果显示:洪泽湖湿地的生态脆弱性综合指数为3.155 4,已呈显著的中度脆弱。评价结果同洪泽湖湿地脆弱性分析特征具有较好的一致性。

关键词：洪泽湖湿地生态脆弱性层次分析法评价

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The Geomorphologic Process of the Diamicton in Jinpingzi in the Valley of Jinsha River,china

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地学前缘 2009年第S1期16卷 45-45页

作者： Qinmian Xu~1,Dayuan Yang~2,Zhaoshuai Ge~3 1.Tianjin Institute of Geology and Mineral Resources,Tianjin 300170,china. 2.school of geographic and oceanographic sciences,nanjing university,nanjing 210093,china 3.school of Urban and Environmental sciences,Xuzhou Normal university,Xuzhou 221116,china

The diamicton of Jinpingzi,which looks like a slide according to morphological character,lies on the Kangdian tectonic *** as geomorphologic, sedimentary characteristics and stratigraphy of the diamicton of Jinpingzi,there are three geomorphologic processes,which are accumulation and sidesway(197-137 ka B.P.),divagation and incision(137-41ka B.P.) and intensity

关键词： the Jinsha River:diamicton Late Medio-Pleistocene geomorphic process

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Spatial distribution of 10m firn temperature in the Antarctic Ice Sheet

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Science china Earth sciences 2011年第5期54卷 655-666页

作者： WANG YeTang1,3 & HOU ShuGui2,3 1 Shandong Marine Fisheries Research Institute,Yantai 264006,china 2 MOE,Key Laboratory for Coast and Island Development,school of geographic and oceanographic sciences,nanjing university,nanjing 210093,china 3State Key Laboratory of Cryospheric Science,Cold and Arid Regions Environmental and Engineering Research Institute,Chinese Academy of sciences,Lanzhou 730000,china Shandong Marine Fisheries Research Institute Yantai China State Key Laboratory of Cryospheric Science Cold and Arid Regions Environmental and Engineering Research Institute Chinese Academy of Sciences Lanzhou China MOE Key Laboratory for Coast and Island Development School of Geographic and Oceanographic Sciences Nanjing University Nanjing China

A database of Antarctic 10 m firn temperature was constructed using available borehole temperature measurements with data quality control to extend knowledge of Antarctic climate. Slopes from a high-resolution digital elevation model and the main ice divide were used to delineate main drainage sectors across Antarctica. In each drainage sector, a quantitative relationship between temperature and latitude, longitude and altitude was established using available tim temperature data. Quantitative relationships incorporating other factors affecting Antarctic air temperature such as atmospheric circulation and small-scale to- pography were used to derive a 10-km resolution grid map of surface temperature. The resulting temperature patterns presented a reasonable depiction of both large and small-scale variations in Antarctic 10 m firn temperature. This map is useful for many spatial variation studies, Antarctic ice sheet models, and comparison with satellite-derived temperature data and outputs of atmospheric general circulation models.

关键词： Antarctica 10 m firn temperature spatial distribution

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The role of aerial algae in the formation of the landscape of the Yunnan Stone Forest,Yunnan Province, china

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Science china Earth sciences 2004年第9期47卷 846-864页

作者： TIAN Youping1,3, ZHANG Jie2, SONG Linhua1 & BAO Haosheng2 1. Institute of geographic sciences and Natural Resources Research, Chinese Academy of sciences, Beijing 100101, china 2. Department of Geography, nanjing university, nanjing 210093, china 3. school of Earth sciences and Resources, china university of Geosciences, Beijing 100083, china Institute of geographic sciences and Natural Resources Research Chinese Academy of Sciences Beijing China school of Earth sciences and Resources China University of Geosciences Beijing China Department of Geography Nanjing University Nanjing China

Aerial algae on the surface of carbonate rocks at the Stone Forest, Shilin County, Yunnan Province, china, and their bioerosion were investigated in the field and studied in the laboratory in detail. Through the observation, identification and statistics of more than one hun- dred algal samples and rock samples with the optical microscopes (stereomicroscope, biological microscope) and the scanning electronic microscope (SEM), the relationships between erosional forms on the surface of the Stone Forest and algae and/or algal communities and the genetic mechanism for the formation of erosional forms were analyzed. It is suggested that aerial algae play an active role in bioerosive processes that may affect the formation of karst erosional forms. These effects include both direct and indirect ones. The direct effect is the initiative control (algal shape-controlling role) of algae on the formation of karst forms of various scales, mostly mi- cro-scale (<10-3m) and minor-scale (10-3-10-1m) erosional forms. The algal shape-controlling roles can be divided into the algal individual shape-controlling role and the algal community shape-controlling role. The former mostly controls the formation of micro-scale erosional forms, while the latter mostly controls the formation of micro-scale and smaller minor-scale erosional forms. The indirect effect refers to the promoting role of algae in the formation of karst forms, which may affect the formation of karst forms of all types and scales. The bioerosion of algae accelerates the weathering process of the whole Stone Forest karst landforms.

关键词： aerial algae, bioerosion, the Stone Forest, Yunnan Province, china.

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Helium isotope investigation on magnetic reversal boundaries of loess-paleosol sequence at Luochuan, central Chinese Loess Plateau

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Chinese Science Bulletin 2007年第17期52卷 2407-2412页

作者： DU XueQing1,6, WANG YongHong2, REN JianGuo3, YE XianRen4 & LU HuaYu5,1 1 State Key Laboratory of Loess and Quaternary Geology, Institute of Earth Environment, Chinese Academy of sciences, Xi’an 710075, china 2 College of Marine Geosciences, Ocean university of china, Qingdao 266003, china 3 National Natural Science Foundation of china, Beijing 100085, china 4 Lanzhou Research Center for Petroleum and Natural Gas Resources, Institute of Geology and Geophysics, Chinese Academy of sciences, Lanzhou 730000, china 5 Key Laboratory of Coast and Island Development, school of geographic and oceanographic sciences, nanjing university, nanjing 210093, china 6 Graduate university of Chinese Academy of sciences, Beijing 100049, china State Key Laboratory of Loess and Quaternary Geology Institute of Earth Environment Chinese Academy of Sciences Xi’an China Graduate university of Chinese Academy of sciences Beijing China College of Marine Geosciences Ocean University of China Qingdao China National Natural Science Foundation of china Beijing China Lanzhou Research Center for Petroleum and Natural Gas Resources Institute of Geology and Geophysics Chinese Academy of Sciences Lanzhou China Key Laboratory of Coast and Island Development School of Geographic and Oceanographic Sciences Nanjing University Nanjing China

Extraterrestrial particles have higher 3He/4He ratios than those of terrestrial sediments ( > 100 Ra versus < 0.03 Ra, where Ra is the 3He/4He ratio normalized to the atmospheric value of 1.4×10?6). The inter- planetary dust particles (IDPs), which are very rich in 3He, continuously bombard the Earth and can accumulate in deposits. IDPs sedimentation rate changes can significantly influence 3He concentration in the Earth surface sediments. Since IDPs are not easy to detect in terrestrial deposits, measuring helium isotopes is a helpful approach to examine changes in IDPs. Helium concentration and helium isotopic composition magnetic substances and the quartz particles were examined for helium concen- tration and helium isotopic ratio. Results show that the 3He/4He ratio and the 3He concentrations of the magnetic substances are clearly higher than those of the bulk samples and the quartz particles, and, the 3He/4He ratio of the extracted magnetic substances is also higher than that of the average level of the Earth’s crust. The higher helium content in the magnetic fractions can be explained by an influx of IDPs.

关键词：中国黄土高原古土壤氦同位素行星际尘埃颗粒反方向磁化

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A new interpolation method for Antarctic surface temperature

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Progress in Natural Science:Materials International 2009年第12期19卷 1843-1849页

作者： Yetang Wang~(a,b),Shugui Hou~(b,c,*) a Monitoring Centre of Ocean Environment of Shandong Province,Yantai 264006,china b State Key Laboratory of Cryospheric Science,Cold and Arid Regions Environmental and Engineering Research Institute, Chinese Academy of sciences,Lanzhou 73000,china c MOE,Key Laboratory for Coast and Island Development,school of geographic and oceanographic sciences,nanjing university,nanjing 210093,china Monitoring Centre of Ocean Environment of Shandong Province Yantai 264006 China State Key Laboratory of Cryospheric Science Cold and Arid Regions Environmental and Engineering Research Institute Chinese Academy of Sciences Lanzhou 73000 China MOE Key Laboratory for Coast and Island Development School of Geographic and Oceanographic Sciences Nanjing University Nanjing 210093 China

We propose a new methodology for the spatial interpolation of annual mean temperature into a regular grid with a geographic resolution of 0.01°for Antarctica by applying a recent compilation of the Antarctic temperature data.A multiple linear regression model of the dependence of temperature on some geographic parameters(i.e.,latitude,longitude,and elevation) is proposed empirically,and the kriging method is used to determine the spatial distribution of regional and local deviations from the temperature calculated from the multiple linear regression *** modeled value and residual grids are combined to derive a high-resolution map of surface air temperature. The performance of our new methodology is superior to a variety of benchmark methods(e.g.,inverse distance weighting,kriging, and spline methods) via cross-validation *** simulation resembles well with those distinct spatial features of surface temperature,such as the decrease in annual mean surface temperature with increasing latitude and the distance away from the coast line; and it also reveals the complex topographic effects on the spatial distribution of surface temperature.

关键词： Surface temperature DEM Antarctica

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Differential Hydrological Grey Model (DHGM) with self-memory function and its application to flood forecasting

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Science china(Technological sciences) 2009年第4期52卷 1039-1049页

作者： CHEN XiangDong1, XIA Jun1,2 & XU Qian3 1 Key Laboratory of Water Cycle and Related Land Surface Processes, Institute of geographic sciences and Natural Resources Research, Chinese Academy of sciences, Beijing 100101, china 2 State Key Laboratory of Water Resources and Hydropower Engineering Science, Wuhan university, Wuhan 430072, china 3 school of Hydrology and Water Resources, Hohai university, nanjing 210098, china Key Laboratory of Water Cycle and Related Land Surface Processes Institute of Geographic Sciences and Natural Resources Research Chinese Academy of Sciences Beijing China State Key Laboratory of Water Resources and Hydropower Engineering Science Wuhan University Wuhan China school of Hydrology and Water Resources Hohai University Nanjing China

This paper addresses a problem of flood forecasting with the self-memory function. Considering flood forecasting’s uncertainty and updating demand, a hybrid hydrological model, namely Differential Hy- drological Grey Model with self-memory function (DHGM-SM), is developed. The model has two fold features. One is to establish a self-memorization equation linked with DHGM, that could extract useful information from past data series and realize updating of hydrological dynamic process. The other is that this model has higher efficiency relative to original hydrological model without self-memory func- tion. This approach was applied to river flow forecasting of two representative basins in Tunxi of South china and Daqinggou of North china. It is shown that this hybrid method has satisfactory forecasting accuracy by examination of both calibration and validation.

关键词： differential grey model the self-memorization principle real-time forecasting faded-memory recursive least square method

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Uncertainty analysis of CO_2 flux components in subtropical evergreen coniferous plantation

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Science china Earth sciences 2009年第2期52卷 257-268页

作者： LIU Min1,2,3, HE HongLin1, YU GuiRui1, LUO YiQi4, SUN XiaoMin1 & WANG HuiMin1 1 Institute of geographic sciences and Natural Resources Research, Chinese Academy of sciences, Beijing 100101, china 2 Gradute school of the Chinese Academy of sciences, Beijing 100049, china 3 school of Geography Science, nanjing Normal university, nanjing 210097, china 4 Department of Botany and Microbiology, university of Oklahoma, 770 Van Vleet Oval, Norman, OK 73019, USA Institute of geographic sciences and Natural Resources Research Chinese Academy of Sciences Beijing China Gradute school of the Chinese Academy of sciences Beijing China school of Geography Science Nanjing Normal University Nanjing China Department of Botany and Microbiology University of Oklahoma Norman USA

We present an uncertainty analysis of ecological process parameters and CO2 flux components (Reco, NEE and gross ecosystem exchange (GEE)) derived from 3 years’ continuous eddy covariance meas-urements of CO2 fluxes at subtropical evergreen coniferous plantation, Qianyanzhou of chinaFlux. Daily-differencing approach was used to analyze the random error of CO2 fluxes measurements and bootstrapping method was used to quantify the uncertainties of three CO2 flux components. In addition, we evaluated different models and optimization methods in influencing estimation of key parameters and CO2 flux components. The results show that: (1) Random flux error more closely follows a dou-ble-exponential (Laplace), rather than a normal (Gaussian) distribution. (2) Different optimization meth-ods result in different estimates of model parameters. Uncertainties of parameters estimated by the maximum likelihood estimation (MLE) are lower than those derived from ordinary least square method (OLS). (3) The differences between simulated Reco, NEE and GEE derived from MLE and those derived from OLS are 12.18% (176 g C·m-2·a-1), 34.33% (79 g C·m-2·a-1) and 5.4% (92 g C·m-2·a-1). However, for a given parameter optimization method, a temperature-dependent model (T_model) and the models derived from a temperature and water-dependent model (TW_model) are 1.31% (17.8 g C·m-2·a-1), 2.1% (5.7 g C·m-2·a-1), and 0.26% (4.3 g C·m-2·a-1), respectively, which suggested that the optimization methods are more important than the ecological models in influencing uncertainty in estimated carbon fluxes. (4) The relative uncertainty of CO2 flux derived from OLS is higher than that from MLE, and the uncertainty is related to timescale, that is, the larger the timescale, the smaller the uncertainty. The relative uncertainties of Reco, NEE and GEE are 4%-8%, 7%-22% and 2%-4% respectively at annual timescale.

关键词： CO2 flux components statistical uncertainty analysis bootstrapping method subtropical evergreen coniferous plantation Qianyanzhou

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