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

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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 Science,Lanzhou University,Lanzhou 730000,china 2 State key laboratory of Palaeobiology and Stratigraphy,Nanjing Institute of Geology and Palaeontology,Chinese Academy of Sciences,Nanjing 210008,china 3 College of Arts and Sciences,Bryant University,Smithfield RI 02917,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 1. key laboratory of Western china’s environmental Systems of the Ministry of Education and College of Earth and environment Science Lanzhou University Lanzhou 730000 China2. State Key Laboratory of Palaeobiology and Stratigraphy Nanjing Institute of Geology and Palaeontology Chinese Academy of Sciences Nanjing 210008 China3. College of Arts and Sciences Bryant University Smithfield RI 02917 USA4. Key Laboratory of Western China’s Mineral Resources and Geological Engineering of Ministry of Education Chang’an University Xi’an 710054 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

A fusion algorithm for remote sensing images based on nonsubsampled pyramids and bidimensional empirical decomposition

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Science china(Technological Sciences) 2010年第S1期53卷 196-204页

作者： ZHANG XiaoDong 1,WANG WenBo 2,WANG DiFeng 3 & ZHANG Yu 4 1 State key laboratory of Information Engineering in Surveying,Mapping and Remote Sensing,Wuhan University,Wuhan 430079,china 2 College of Sciences,Wuhan University of Science and Technology,Wuhan 430065,china 3State key laboratory of Satellite Ocean environment Dynamics,Second Institute of Oceanography,State Oceanic Administration,Hangzhou 310012,china 4 Spatial Information Technology Application Research Institute,Changjiang River Scientific Research Institute,Wuhan 430010,china Wuhan Univ State Key Lab Informat Engn Surveying Mapping & R Wuhan 430079 Peoples R China Wuhan Univ Sci & Technol Coll Sci Wuhan 430065 Peoples R China State Ocean Adm Inst Oceanog 2 State Key Lab Satellite Ocean Environm Dynam Hangzhou 310012 Zhejiang Peoples R China Changjiang River Sci Res Inst Spatial Informat Technol Applicat Res Inst Wuhan 430010 Peoples R China

In order to improve the quality of remote sensing image fusion,a new method combining nonsubsampled Laplacian pyramid (NLP)and bidimensional empirical mode decomposition(BEMD)is ***,the high resolution panchromatic image (PAN)is decomposed using NLP until the approximate component and the low resolution multispectral image(MS)contain features with a similar ***,the approximation component and the MS are decomposed by BEMD,resulting in a number of bidimensional intrinsic mode functions(BIMF)and a residue *** instantaneous frequency is computed in 4 directions of the *** the positive or negative coefficients in the corresponding position,a weighted algorithm is designed for fusing the high frequency details using the instantaneous frequency and the coefficient absolute value of the BIMFs as fusion *** fused image is then obtained through inverse BEMD and *** results have illustrated the advantage of this method over the IHS,DWT andà-Trous wavelet in both spectral and spatial detail qualities.

关键词： bidimensional empirical mode decomposition nonsubsampled pyramid instantaneous frequency remote sensing image fusion

Comparative study on using carbon or nitrogen limited medium to culture white rot fungi for reactive brilliant red dye K-2BP decolotization under non-sterile conditions

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Science china Chemistry 2007年第5期50卷 718-724页

作者： GAO DaWen1,2, WEN XiangHua1 & QIAN Yi1 1 State key Joint laboratory of environmental Simulation and Pollution Control, Department of environment Science and Engi- neering, Tsinghua University, Beijing 100084, china 2 School of Forestry, Northeast Forestry University, Harbin 150040, china State key Joint laboratory of environmental Simulation and PollutionControl Department of Environment Science and EngineeringTsinghua UniversityBeijing100084China School of Forestry Northeast Forestry UniversityHarbin 150040China

In order to explore ways for the application of white rot fungus in dye effluent treatment under non-sterile conditions, experiment on decolorization of reactive brilliant red was carried out, employing nitrogen-limited and carbon-limited medium with C/N ratio of 56/2.2 and 28/44 (in mmol/L), respectively. The results showed that the decolorization rate reached 92% while culturing white rot fungus with ni- trogen-limited medium; however, the decolorization process ended in carbon-limited medium (n(C)/n(N) = 28/44) because of bacterial contamination. In addition, pH rose up to 9.31 after 4 d of decolorization, which was caused by bacterial contamination in the carbon-limited system. Therefore, it is concluded that nitrogen-limited medium can inhibit bacterial growth to some extent while carbon-limited medium is more easily contaminated by bacteria. Nitrogen-limited medium is more suitable in culture of white rot fungus for decolorization of reactive dye. Medium with the ability of inhibiting yeast growth should be developed by adjusting other components of nitrogen-limited medium.

关键词： white rot fungus, Phanerochaete chrysosporium, non-sterile, decolorization, dye

Ostracod fauna across the Permian-Triassic boundary at Chongyang, Hubei Province, and its implication for the process of the mass extinction

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Science china Earth Sciences 2010年第6期53卷 810-817页

作者： LIU Hao1, WANG YongBiao1, YUAN AiHua2, YANG Hao1, SONG HaiJun1 & ZHANG SuXin21 key laboratory of Biogeology and environmental Geology of Ministry of Education, Wuhan 430074, china 2 State key laboratory of Geological Processes and Mineral Resources, Wuhan 430074, china 1. key laboratory of Biogeology and environmental Geology of Ministry of Education Wuhan 430074 China2. State Key Laboratory of Geological Processes and Mineral Resources Wuhan 430074 China

Thirty species of 10 ostracod genera were identified from 440 fossil specimens isolated through the hot acetolysis of the rock samples collected across the Permian-Triassic boundary at Chongyang section. Twenty species of 6 genera are found to occur in the limestone of Changxing Formation, and 11 species of 7 genera above the main faunal mass extinction horizon. The os-tracod assemblages identified at the Chongyang section are obviously different from those previously reported in the contem-poraneous microbialites in Guangxi and Chongqing regions, not only in the ostracod components but also in the abundance of filter-feeding ostracods relative to the deposit-feeding ostracods, an indicator of the oxygen level of the seawater. This spatial difference in ostracod assemblages might reflect the diversity of oceanic environmental conditions after the end-Permian mass extinction. Ostracods disappear at 200 cm below and near the main mass extinction horizon, and on the top of the microbialites, respectively, showing an episodic and gradual collapse process at the Chongyang section. The carbon isotope composition is found to appear at 200 cm below the main mass extinction horizon, indicating the initial deterioration of oceanic environment. Fluctuation of the carbon isotope composition is obviously related with the episodic evolution of ostracod species, but not with the abundance of ostracods.

关键词： ostracod microbialite Permian-Triassic mass extinction Chongyang

Advances in numerical methods for the solution of population balance equations for disperse phase systems

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Science china Chemistry 2009年第8期52卷 1063-1079页

作者： SU JunWei1,GU ZhaoLin2,3 & XU X.Yun41 Department of Mechanical Engineering and Automation,School of Mechanical Engineering,Xi’an Jiaotong University,Xi’an 710049,china 2 key laboratory of Mechanics on Disaster and environment in Western china,Ministry of Education,Lanzhou 730000,china 3 Department of environmental Science and Technology,School of Human Settlements and Civil Engineering,Xi’an Jiaotong University,Xi’an 710049,china 4 Department of Chemical Engineering,Imperial College London,London SW7 2AZ,UK 1. Department of Mechanical Engineering and Automation School of Mechanical Engineering Xi’an Jiaotong University Xi’an 710049 China 2. key laboratory of Mechanics on Disaster and environment in Western china Ministry of Education Lanzhou 730000 China 3. Department of environmental Science and Technology School of Human Settlements and Civil Engineering Xi’an Jiaotong University Xi’an 710049 China 4. Department of Chemical Engineering Imperial College London London SW7 2AZ UK

Accurate prediction of the evolution of particle size distribution is critical to determining the dynamic flow structure of a disperse phase system.A population balance equation(PBE),a non-linear hyperbolic equation of the number density function,is usually employed to describe the micro-behavior(aggregation,breakage,growth,etc.) of a disperse phase and its effect on particle size *** solution is the only choice in most *** this paper,three different numerical methods(direct discretization methods,Monte Carlo methods,and moment methods) for the solution of a PBE are evaluated with regard to their ease of implementation,computational load and numerical *** attention is paid to the relatively new and superior moment methods including quadrature method of moments(QMOM),direct quadrature method of moments(DQMOM),modified quadrature method of moments(M-QMOM),adaptive direct quadrature method of moments(ADQMOM),fixed pivot quadrature method of moments(FPQMOM),moving particle ensemble method(MPEM) and local fixed pivot quadrature method of moments(LFPQMOM).The prospects of these methods are discussed in the final section,based on their individual merits and current state of development of the field.

关键词： population balance equation direct discretization method Monte Carlo method moment methods disperse phase system

Optimum segmentation of simple objects in high-resolution remote sensing imagery in coastal areas

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Science china Earth Sciences 2006年第11期49卷 1195-1203页

作者： CHEN Jianyu1,2, PAN Delu1 & MAO Zhihua1 1. State key laboratory of Satellite Ocean environment Dynamics, Second Institute of Oceanography, State Oceanic Admini- stration, Hangzhou 310012, china 2. Shanghai Institute of Technical Physics, Chinese Academy of Science, Shanghai 200083, china 1. State key laboratory of Satellite Ocean environment Dynamics Second Institute of Oceanography State Oceanic Administration Hangzhou 310012 China 2. Shanghai Institute of Technical Physics Chinese Academy of Science Shanghai 200083 China

The optimum segmentation of ground objects in a landscape is essential for interpretation of high-resolution remotely sensed imagery and detection of objects; and it is also a technical foundation to efficiently use spatial information in remote sensing imagery. Landscapes are complex system composed of a large number of heterogeneous components. There are many explicit homogeneous image objects that have similar spectral character and yet differ from surrounding objects in high-resolution remote sensing imagery. Thereby, a new concept of Distinctive Feature of fractal is put forward and used in deriving Distinctive Feature curve of fractal evolution in multiscale segmentation. Through distinguishing the extremum condition of Distinctive Feature curve and the inclusion relationship of fractals in multiscale representation the Scalar Order is built. This can help to determinate the optimum scale in image segmentation for simple-objects, and the potential meaningful image-object fitting the intrinsic scale of the dominant landscape object can be obtained. Based on the application in high-resolution remote sensing imagery in coastal areas, a satisfactory result was acquired.

关键词： optimum scale, multiscale segmentation, image interpretation, remote sensing, coastal area.

A technique on automatic land-use database reconstruction based on scanning land-use map

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Science china(Technological Sciences) 2006年第z2期49卷 57-63页

作者： LI Xiaojuan, GONG Huili, YIN Lianwang, SUN Yonghua, YANG Lingli & WANG Yanggang key laboratory of 3D Information Acquisition and Application, Ministry of Education, Capital Normal University, Beijing 100037, china key laboratory of Resource environment and GIS of Beijing, Capital Normal University, Beijing 100037, china Capital Normal Univ Minist Educ Key Lab D Informat Acquisit & Applicat 3 Beijing 100037 Peoples R China Capital Normal Univ Key Lab Resource Environm Beijing 100037 Peoples R China Capital Normal Univ GIS Beijing Beijing 100037 Peoples R China

Although a land-cover database is very important to national land use including urban planning and land-use management, it is very laborious and time-consuming to build through digitization of paper land-use maps (1:10000) and data input by hand. Here we propose a new, high-level, automatic technique to build a land-use database, which has proved useful and practical in building a land-use database of Baotou City.

关键词： land-use map vectonzation automatic building of land-use database.

A study on water film in saturated sand

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International Journal of Sediment Research 2010年第3期25卷 221-232页

作者： LU X. B.1 and CUI P.2 1 Dr., laboratory for Hydraulic and Ocean Engineering, Institute of Mechanics, Chinese Academy of Sciences, Beijing 100190, china, 2 Prof., key laboratory for Mountain Hazard and Earth Surface Process, Institute of Mountain Hazard and environment, Chinese Academy of Sciences, Chengdu 610041, china, [a] Dr. Laboratory for Hydraulic Ocean Engineering Institute of Mechanics Chinese Academy of Sciences Beijing 100190 China [b] Prof. Key Laboratory for Mountain Hazard Earth Surface Process Institute of Mountain Hazard environment Chinese Academy of Sciences Chengdu 610041 China

Water film can serve as a sliding surface and cause landslides on gentle slopes. The development of "water film" in saturated sand is analyzed numerically and theoretically based on a quasi-three-phase model. It is shown that stable water films initiate and grow if the choking state (where the fluid velocity decreases to near zero) remains steady in a liquefied sand column. Discontinuity can occur in pore water velocity, grain velocity and pore pressure after the initiation of a water film. However, the discontinuity and water film can disappear once the choking state is changed. The key to the formation of water film is the choking in the sand column caused by eroded fine grains.

关键词： Saturated sand Water film Liquefaction

Some evidence of drying trend over northern china from 1951 to 2004

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Chinese Science Bulletin 2006年第23期51卷 2913-2925页

作者： MA Zhuguo1,2 & FU Congbin1,2 1. key laboratory of Regional Climate-environment for Temperate East Asia, Chinese Academy of Sciences, Beijing 100029, china 2. START Regional Center for Temperate East Asia, Institute of Atmos-pheric Physics, Chinese Academy of Sciences, Beijing 100029, china key laboratory of Regional Climate-environment for Temperate East Asia Chinese Academy of Sciences Beijing 100029 China START Regional Center for Temperate East Asia Institute of Atmospheric Physics Chinese Academy of Sciences Beijing 100029 China

The surface wetness index, Palmer drought sererity index and the retrieval of soil moisture over china were calculated using monthly precipitation and monthly mean surface air temperature. Based on the contrast analysis of the variation of the above three indices and precipitation, the dry/wet spatio-temporal pattern of northern china in the last 54 years was revealed, and the evidence of drying trend over northern china was analyzed, especially. The results show the following four facts: (1) The drying trend is the main characteristic of the eastern part of Northwest china and the central part of North china since the 1980s and it was enhanced in the last 15 years mainly due to the precipitation decrease and the temperature increase; (2) During the last 54 years, there was only one dry/wet shift at the interdecadal scale occurring in the eastern part of Northwest china and the central part of North china in the late 1970s, which was related to 1977/1978 global abrupt change, whereas there were three shifts in Northeast china, one was in the mid 1990s and the other two were in 1965 and 1983, respectively; (3) Unlike the variation trend of other subregions of northern china, the western part of Northwest china is currently located in a relatively wetting period, which is weak-ened due to the temperature increase; (4) The extreme drought frequency is obviously increasing in the eastern part of Northwest china, the central part of North china and Northeast china since the 1980s, which is closely related to the precipitation decrease and temperature increase in these subregions.

关键词：中国北方干燥趋向干旱索引气候背景