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Anatomical variations of living and fossil Liquidambar leaves:A proxy for paleoenvironmental reconstruction

science china Earth sciences 2011年第4期54卷 493-508页

作者： XIAO Liang 1,2.3,4,sUN BaiNian 1,2.,LI Xiangchuan 1,REN WenXiu 1 &JIA Hui 1 1 Key Laboratory of Western china's environmental systems of the Ministry of Education and college of Earth and Environment {2.,Lanzhou University,Lanzhou 730000,china 2.state Key Laboratory of Palaeobiology and stratigraphy,Nanjing Institute of Geology and Palaeontology,chinese Academy of {2.s,Nanjing 2.0008,china 3 college of Arts and {2.s,Bryant University,smithfield RI 02.17,U.s.A. 4 Key Laboratory of Western china's Mineral resources and Geological Engineering of Ministry of Education,chang’an University,Xi’an 710054,china Key Laboratory of Western china’s environmental systems of the Ministry of Education and college of Earth and Environment {2. Lanzhou University Lanzhou China state Key Laboratory of Palaeobiology and stratigraphy Nanjing Institute of Geology and Palaeontology Chinese Academy of Sciences Nanjing China college of Arts and sciences Bryant University Smithfield USA Key Laboratory of Western china’s Mineral resources and Geological Engineering of Ministry of Education Chang’an University Xi’an China

Based on living ***,we have established that such epidermal cell properties as epidermal cell circumference(circum.) ,undulation index(UI) ,epidermal cell area(EA) on both upper and lower epidermis and the corresponding epidermal cell density(ED) ,are suitable to differentiate between sun and shade ***,stomatal properties on the lower epidermis,including stomatal length(sL) ,stomatal pore length(PL) and the corresponding stomatal density(sD) ,are reliable parameters to identify sun/shade *** this anatomical approach was applied to 18 leaf remains of *** from the Miocene Xiannanshan Formation,Zhejiang Province(eastern china) ,and the fossil leaves were sorted into two groups,namely,sun and shade *** indicates that anatomical differences between sun and shade leaves found in living species could be used for fossil ***,the variation of UI between sun and shade morphotypes is larger on the upper epidermis as compared with the lower epidermis,showing that the UI on the upper epidermis is more sensitive to environmental *** addition,anatomical features are more variable in sun leaves than in shade leaves for both modern and fossil Liquidambar,suggesting sun leaves may be more sensitive to environmental *** leaves can then be a better indicator of paleoenvironmental ***,stomatal parameters of sun morphotype should be adopted on reconstructing paleoenvironments using Liquidambar leaf *** the other hand,the three-lobed fossil *** leaf assemblage in the Xiananshan Formation is represented by an almost similar percentage of sun and shade morphotypes(56%and 44%,respectively) ,which is attributed to the short transport before *** a result,identifying sun/shade morphotypes are very useful in reconstructing paleoenvironments based on fossil leaves of Liquidambar.

关键词： Liquidambar formosana Liquidambar miosinica leaf anatomy the Miocene Xiananshan Formation sun and shade leaves

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Important progress on the use of isotope techniques and methods in catchment hydrology

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Research in cold and Arid Regions 2009年第3期1卷 207-214页

作者： JinKui Wu 1,2. YongJian Ding 1, Baisheng Ye 1, QiYue Yang 3, Zhi Wei 1 1. Key Laboratory of Ecological Hydrology and Basin sciences in cold and Arid Regions environmental and Engineering Re-search Institute, chinese Academy of sciences, Lanzhou, gansu 730000, china. 2. Institute for Landscape Ecology and resources Management, Justus-Liebig-University Giessen, Giessen 35392. Germany. 3. college of Earth and environmental science, Lanzhou University, Lanzhou, gansu 730000, china. chinese Acad sci Cold & Arid Reg Environm & Engn Res Inst Key Lab Ecol Hydrol & Basin Sci Lanzhou 730000 Gansu Peoples R China Justus Liebig Univ Giessen Inst Landscape Ecol & Resources Management D-35392 Giessen Germany Lanzhou Univ Coll Earth & Environm Sci Lanzhou 730000 Gansu Peoples R China

The use of isotope techniques and methods in catchment hydrology in the last 50 years has generated two major types of progress: (1) Assessment of the temporal variations of the major stocks and flows of water in catchments, from which the estimation of wa-ter residence times is introduced in this paper. (2. Assessment of catchment hydrologic processes, in which the interactions be-tween different waters, hydrographical separation, and bio-geochemical process are described by using isotopes tracers. Future progress on isotope techniques and methods in hydrology is toward the understanding of the hydrological process in large river basins. Much potential also waits realization in terms of how isotope information may be used to calibrate and test distributed rainfall-runoff models and regarding aid in the quantification of sustainable water resources management.

关键词： isotope hydrological process catchment progress

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The impact of vegetation restoration on erosion-induced sediment yield in the middle Yellow River and management prospect

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science china Earth sciences 2005年第6期48卷 724-741页

作者： cHEN Hao1, ZHOU Jinxing2. cAI Qiangguo1, YUE Zhongqi3, LU Zhongchen4, LIANG Guanglin1& HUANG Jianguo5 1. Key Laboratory of Water cycle and Related Land surface Processes, Institute of Geographic sciences and Natural resources Re-search, chinese Academy of sciences, Beijing 100101, china 2. Institute of Forestry, chinese Academy of Forestry sciences, Beijing 100091, china 3. Department of civil Engineering, University of Hong Kong, Hong Kong, china 4. Eco-environmental Research center, chinese Academy of sciences, Beijing 100085, china 5. college of resources and Environment, southwest Agricultural University, chongqing 400716, china correspondence should be addressed to chen Hao Key Laboratory of Water cycle and Related Land surface Processes Institute of Geographic Sciences and Natural Resources Research Chinese Academy of Sciences Beijing China Institute of Forestry Chinese Academy of Forestry Sciences Beijing China Department of civil Engineering University of Hong Kong Hong Kong China Eco-environmental Research center Chinese Academy of Sciences Beijing China college of resources and Environment Southwest Agricultural University Chongqing China

According to the characteristics of water and erosion environments of different natural zones on the Loess Plateau, this paper studies changes of vegetation types, distribution boundaries of forest and grass as well as restoration capacity of vegetation in different natural zones in the middle Yellow River. The annual precipitation of 530 mm is the critical annual pre-cipitation for forest and grass distribution in the middle Yellow River. Among the zonal and azonal environmental factors affecting watershed sediment yield, the intermediate diameter D50 (mm) of suspended load and forest coverage (V, %) play the leading role. Of them the effect weight of forest coverage (V, %) on catchments sediment yield is only 3.4% less than the role of the intermediate diameter (D50, mm), they are almost the same. To effectively control soil erosion in semiarid, especially in hilly-gullied areas and make sediment transport modulus reduce to less than 6000 t/km2. it is rather difficult by merely relying on natural restoration of forest. In the process of cultivated land conversion into forest land and grassland, measures suiting local conditions should be adopted in tree species selection and artificial afforestation (grass planting) based on management with biological measures for slopeland and engineering measures for hilly-gullied areas, so that watershed forest coverage in key counties can reach at least over 30%.compared with the standard period of precipitation prior to the 1960s, with the decrease of an-nual precipitation at various periods, plant productivities decline to different degrees under natural conditions. The main reason accountable for the low survival rate of new seedlings and grass over years is due to precipitation decrease. In light with regression models of annual pre-cipitation and natural vegetation productivities, it is possible to obtain estimated values of wa-tershed natural vegetation productivity and eco-water consumption needed for the restoration to

关键词： vegetation restoration, eco-water requirement, watershed sediment yield, the middle Yellow River.

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Response of cucumber plants to increased UV-B radiation under water stress

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Journal of environmental sciences 2000年第2期12卷 111-115页

作者： YANG Zhi\|min\+1, ZHENG shao\|jian\+2. HU Ai\|tong\+1, ZHENG You\|fei\+3, YAN Jing\|yi\+3 (1. college of science, Nanjing Agricultural University, Nanjing 2.0095, china 2. college of Natural {2. and environmental sciences, Nanjing Agricultural

Three days old cucumber (cucumis sativus L.) was grown in a factorial design under two levels of water condition (well watered and drought) and two supplemental levels of ultraviolet\|B(2.0—32. nm) irradiance(0, 0\^2., 0\^42.W/m\+2. for 30 days. Plants were grown in a greenhouse under visible light with 400 μmol/(m\+2.s), day\|night temperature 32.2.℃ and relative humidity 70±10%. The combination of UV\|B radiation and water stress resulted in the decrease in plant height, leaf area ratio and relative growth rate, and increase in specific leaf mass and net assimilation rate. There was almost no effect of ultraviolet\|B radiation on the contents of chlorophyll a and b under water stress. However, interactive effects of ultraviolet\|B radiation and water conditions on the content of anthocyanin were much great. UV\|B irradiance with water stress also caused a reduction in net photosynthesis, apparent quantum efficiency, gas exchange and stomatal resistance, and an increase in evaporation.

关键词： cucumber UV\|B water stress interaction. cLc number: s181 Document code: A

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Uptake of Organic Phosphorus by Arbuscular Mycorrhizal Red clover

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Pedosphere 2002年第2期12卷 103-110页

作者： sONGYONGcHUN P.cHRIsTIE DepartmentofPlantNutrition CollegeofAgriculturalResourcesandEnvironmentalSciencesChinaAgriculturalUniversityBeijing100094（China） DepartmentofAgriculturalandenvironmentalscience The

The capacities of two arbuscular mycorrhizal (AM) fungi, Glomus mosseae and Glomus versderme, tomineralize added organic P were studied in a sterilized calcareous soil. Mycorrhizal (inoculated with eitherof the AM fungi) and non-mycorrhizal red clover (Trghlium pmtense L.) plants were grown for eight weeksin pots with upper root, central hyphal and lower soil compartments. The hyphal and soil compartmentsreceived either organic P (as Na-phytate) or inorganic P (as KH2.O4) at tbe rate of 50 mg P kg-1. No P wasadded to the root compartments. control pots received no added P. Yields were higher in mycorrhizal than innon-mycorrhizal clover. Mycorrhizal inoculation doubled shoot P concentration and more than doubled totalP uptake of plaflts in P-amended soil, irrespective of the form of applied P. The mycorrhizal contributionto inorganic P uptake was 80% or 76% in plants inoculated with G. mosseae or G. verefforme, *** va1ues were 74% and 82. when Na-phytate was

关键词：土壤杀菌石灰质矿化植物真菌类生长磷红三叶草

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Lithosphere types in North china:Evidence from geology and geophysics

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science china Earth sciences 2005年第11期48卷 1809-1827页

作者： QIU Ruizhao1,2. DENG Jinfu3, ZHOU su3, LI Jinfa4, XIAO Qinghui1,5, WU Zongxu6 & LIU cui3 1. Institute of Geology, chinese Academy of Geological sciences, Beijing 100037, china 2. Development and Research center, china Geological survey, Beijing 100037, china 3. china University of Geosciences, Beijing 100083, china 4. china University of Geosciences, Wuhan 430074, china 5. information center of Ministry of Land and resources, Beijing 100812. china 6. Institute of Geology, state seismological Bureau, Beijing 10002., china Institute of Geology Chinese Academy of Geological Sciences Beijing China Development and Research center China Geological Survey Beijing China china University of Geosciences Beijing China china University of Geosciences Wuhan China information center of Ministry of Land and resources Beijing China Institute of Geology State Seismological Bureau Beijing China

On the basis of the characteristics of geology and geophysics in North china, three types of lithosphere, namely, the cratonic, the orogenic and the rift lithospheres can be c.a.s.fied. In terms of petrological method (based on the {2. from Precambrian rock assemblages, igneous activities, deep-seated enclaves, etc.) and the relationship between seismic velocity and rock compositions, the crust-mantle petrological and chemical structure models can be set up. Researching results indicate that the geology and geophysics of North china platform bears the similar characteristics in comparison with those of the global typical cratons. The Eerduosi(Ordos) block located in the west of the North china Platform is a remnant of cratonic lithosphere after the North china platform had undergone “activation” in Mesozoic and “reconstruction” in cenozoic times. The continental crust consists mainly of TTG rock assemblage while the subcontinental lithosphere mantle mainly consists of strongly depleted harzburgite. The craton was finally formed in late Archaean and early Proterozoic, and has been kept in stability up to present; its crustal-mantle petrological structures of lithosphere can be set up as a reference for the study of North china craton and even sino-Korean craton. In the Mesozoic period, the middle and east areas of North china platform were activated in the Yanshanian orogenic process, the continental crust was reformed by material and heat-transfer of convective mantle and the original crustal TTG component was reconstructed to be granitic crust, and the subcontinental lithosphere man- tle was replaced by the Yanshanian harzburgite-lherzolite. The Yanshan-Taihang Mountains were the remnants of orogenic lithosphere after the rifting in eastern North china in cenozoic. The present thickness of continental crust and lithosphere in the Yanshan-Taihang Mountains is not equal to their thickness during the Yanshanian orogenic movement because they had undergone the

关键词： lithospheric types,evidence of geology and geophysics,crust-mantle petrological structure,deep process

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Identification of Prorocentrum minimum and Takayama pulchella by fluorescence in situ hybridization through epifluorescence microscopy and flow cytometry

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Acta Oceanologica sinica 2009年第2期28卷 103-114页

作者： HOU Jianjun LAI Hongyan HUANG Bangqin cHEN Jixin college of Fisheries Huazhong Agricultural University Wuhan 430070 China college of Life sciences Hubei Normal University Huangshi 435002 China state Key Laboratory of Marine environmental science Environmental Science Research Center Xiamen University Xiamen 361005 China Key Laboratory of Freshwater Fish Germplasm resources and Biotechnology Yangtse River Fisheries Research Institute Jinzhou 434000 China state Key Laboratory of Freshwater Ecology and Biotechnology Institute of Hydrobiology Chinese Academy of Sciences Wuhan 430072 China

Partial rDNA sequences of Prorocentrum minimum and Takayama pulchella were amplified, cloned and sequenced, and these sequence data were deposited in the GenBank. Eight oligonucleotide probes （DNA probes） were designed based on the sequence analysis. The probes were employed to detect and identify P. minimum and T. pulchella in unialgal and mixed algal samples with a fluorescence in situ hybridization method using flow cytometry. Epifluorescence micrographs showed that these specific probes labeled with fluorescein isothiocyanate entered the algal cells and bound to target sequences, and the fluorescence signal resulting from whole-cell hybridization varied from probe to probe. These DNA probes and the hybridization protocol we developed were specific and effective for P. minimum and T. pulchella, without any specific binding to other algal species. The hybridization efficiency of different probes specific to P. minimum was in the order： PM18s02.PM2.s02.〉 PM2.s01 〉PM18s01, and that of the probes specific to T. pulcheUa was TP18s02.TP2.s01 〉 TP2.s02. 〉TP18s01. The different hybridization efficiency of the DNA probes could also be shown in the fluorescent signals between the labeled and unlabeled cells demonstrated using flow cytometry. The DNA probes PM18s02. PM2.s02. TP18s02.and TP2.s01, and the protocol, were also useful for the detection of Mgae in natural samples.

关键词： oligonucleotide DNA probes Prorocentrum minimum Takayama pulcheUa fluorescence in situ hybridization flow cytometry

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study of attenuation depths for MODIs bands in the Bohai sea in china

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Acta Oceanologica sinica 2009年第5期28卷 39-48页

作者： LIU Ying LI Guosheng Institute of Geographic sciences and Natural resources Research Chinese Academy of Science Beijing 100101 China Xinjiang Institute of Ecology and Geogrphy Chinese Academy of Science Urumqi 830011 China

An attenuation depth is defined for remote sensing purposes as a depth above which 90% of the arising light leaving the water surface is originated. The deeper the attenuation depth, the more information of water is detectable by remote sensing, then the more precise information of water is extracted. Meanwhile, the attenuation depth is helpful to know water layer （by its thickness） from which remote sensing will be able to extract information. A number of investigators are using the moderate resolution imaging spectroradiometer （or MODIs） for remote sensing of ocean color. It is necessary to have a rough idea of the effective attenuation depth of imagery in each of the spectral bands employed by the MODIs. The attenuation depth is directly determined from MODIs data. Though analyzing the spectral distribution of the attenuation depth on 7 August 2.03 and the seasonal variation of the attenuation depth （551 nm） in the Bohai sea indicated that： the spectral distribution of the attenuation depth for the spectral range between 400 to 700 nm is single-peak curve, and it’s similar and difference in different regions is consistent with other scholars’ results of zoning, moreover, it supports the Bohai sea is case 2.water; the maximum attenuation depth shifts toward longer wavelengths, liking the red shift, with increase of turbidity of water, just like the maximum attenuation depth in the outside of the northwest coast of the Bohai sea and the Bohai strait is at 531nm, in the central of the Bohai sea is at 551nm, in the region controlled by the Huanghe （Yellow） River, the region impacted by the old Huanghe River, the western side of the Liaodong Bay and the eastern side of the Liaodong Bay is at 555 nm; the seasonal change of the attenuation depth is the largest in the summer, followed by the fall, and the ranking of winter and spring in different regions is distinct. The attenuation depth in different regions is dissimilar： the order of the attenuation depth in different

关键词： attenuation depth MODIs Bohai sea

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study on Water consumption coefficient of People's Living and Its Regional Disparity in the North of china

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chinese Journal of Population,resources and Environment 2005年第2期3卷 20-26页

作者： Wang Jing’ai 1-3, Mao Rui 3,4, Yang Mingchuan 3,4 & Zhou Junju 11 college of Geography & Remote sensing 2.Key Laboratory of Regional Geography of Beijing Normal University 3 Key Laboratory of environmental change and Natural Disaster of Ministry of Education of china 4 college of {2. science & Technology, Beijing Normal University, Beijing 100875, china college of Geography and Remote sensing Beijing 100048 China Key Laboratory of environmental change and Natural Disaster of Ministry of Education of china Beijing 100048 China college of resources science and Technology Beijing Normal University Beijing 100875 China

By employing the information-reshufflingmethod that integrates census data, precipitation dataand inquiry data of water consumption, this paperdiscusses 5 (water consumption coefficient of people’sliving) in allusion to different precipitation zones anddifferent periods of time. The study shows that 5-(water consumption coefficient of urban people’sliving), 5. (water consumption coefficient of ruralpeople’s living) and increase with time passing, andthe increasing extent of 5 is 1.84, 2.62. 2.84 and 2.68times respectively from the west to the east, whichresults from the total quantity of water resources andthe speed of urbanization. 5- and 5. of eachprecipitation zone increased with 5- increasing morequickly than 5., and the difference between the twoalso increased when time passed. In the past fifty years(1950-2.00), the increasing extent of 5- was 1.71,2.96, 2.41 and 2.33 times respectively from the westto the east, in which 2.0-400mm precipitation zoneincreased more than others. Meanwhile the increasingextent of 5. is 1.55, 1.60, 1.53 and 1.64 timesrespectively from the west to the east with eachprecipitation zone increasing similarly. The change of5-is due to the speed of urbanization and the stabilityof water resources. This study provides basis forcalculating the water demand of people’s living andrevealing the impact of water demand of people’s livingon ecological drought in different zones.

关键词： The north of china precipitation zone water consumption coefficient of people’s living

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2.5-D modeling of cross-hole electromagnetic measurement by nite element method

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Petroleum science 2008年第2期5卷 126-134页

作者： shen Jinsong sun Wenbo Department of Geophysics School of Resources and Information Technology China University of Petroleum Beijing 102249 China cNPc Key Lab of Geophysical Exploration China University of Petroleum Beijing 102249 China

A finite element method is developed for simulating frequency domain electromagnetic responses due to a dipole source in the 2.D conductive structures. computing costs are considerably minimized by reducing the full three-dimensional problem to a series of two-dimensional problems. This is accomplished by transforming the problem into y-wave number （Ky） domain using Fourier transform and the y-axis is parallel to the structural strike. In the Ky domain, two coupled partial differential equations for magnetic field Hy and electric field Ey are derived. For a specific value of Ky, the coupled equations are solved by the finite element method with isoparametric elements in the x-z plane. Application of the inverse Fourier transform to the Ky, domain provides the electric and magnetic fields in real space. The equations derived can be applied to general complex two-dimensional structures containing either electric or magnetic dipole source in any direction. In the modeling of the electromagnetic measurement, we adopted a pseudo-delta function to distribute the dipole source current and circumvent the problem of singularity at the source point. Moreover, the suggested method used isoparametric finite elements to accommodate the complex subsurface formation. For the large scale linear system derived from the discretization of the Maxwell＇s equations, several iterative solvers were used and compared to select the optimal one. A quantitative test of accuracy was presented which compared the finite element results with analytic solutions for a dipole source in homogeneous space for different ranges and different wave numbers Ky. to validate the addressed the effects of the distribution range τ of the homogeneous medium. code and check its effectiveness. In addition, we pseudo-delta function on the numerical results in

关键词： 2.5-D electromagnetic modeling frequency domain isoparametric finite element pseudo-delta function

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