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Impacts of permafrost changes on alpine ecosystem in Qinghai-Tibet Plateau

Science china Earth Sciences 2006年第11期49卷 1156-1169页

作者： WANG Genxu1,3., LI Yuanshou2 , WU Qingbai2 & WANG Yibo3.1. Institute of Mountain Hazards and environment, Chinese Academy of Sciences, Chengdu 610041, china 2. Cold and Arid Regions environmental and Engineering Research Institute, Chinese Academy of Sciences,{3., china 3. resource and environment school, lanzhou university,{3., china Institute of Mountain Hazards and environment Chinese Academy of Sciences Chengdu China resource and environment school Lanzhou University Lanzhou China Cold and Arid Regions environmental and Engineering Research Institute Chinese Academy of Sciences Lanzhou China

Alpine cold ecosystem with permafrost environment is quite sensitive to climatic changes and the changes in permafrost can significantly affect the alpine ecosystem. The vegetation coverage, grassland biomass and soil nutrient and texture are selected to indicate the regime of alpine cold ecosystems in the Qinghai-Tibet Plateau. The interactions between alpine ecosystem and permafrost were investigated with the depth of active layer, permafrost thickness and mean annual ground temperature (MAGTs). Based on the statistics model of GPTR for MAGTs and annual air temperatures, an analysis method was developed to analyze the impacts of permafrost changes on the alpine ecosystems. Under the climate change and human engineering activities, the permafrost change and its impacts on alpine ecosystems in the permafrost region between the Kunlun Mountains and the Tanggula Range of Qinghai-Tibet Plateau are studied in this paper. The results showed that the per- mafrost changes have a different influence on different alpine ecosystems. With the increase in the thickness of active layer, the vegetation cover and biomass of the alpine cold meadow exhibit a significant conic reduction, the soil organic matter content of the alpine cold meadow ecosystem shows an exponential decrease, and the surface soil materials become coarse and gravelly. The alpine cold steppe ecosystem, however, seems to have a relatively weak relation to the permafrost environment. Those relationships resulted in the fact that the distribution area of alpine cold meadow decreased by 7.98% and alpine cold swamp decreased by 28.11% under the permafrost environment degradation during recent 15 years. In the future 50 years the alpine cold meadow ecosystems in different geomorphologic units may have different responses to the changes of the permafrost under different climate warming conditions, among them the alpine cold meadow and swamp ecosystem located in the low mountain and plateau area will have a relatively

关键词： permafrost environment, alpine cold ecosystem, statistics relationship, climate change, impacts, Qinghai-Tibet Plateau.

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Impact of land-use change on hydrological processes in the Maying River basin, china

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Science china Earth Sciences 2006年第10期49卷 1098-1110页

作者： WANG Genxu1,3. ZHANG Yu2, LIU Guimin2 & CHEN Lin3.1. Institute of Mountain Hazards and environment, Chinese Academy of Sciences, Chengdu 610041, china 2. Cold and Arid Regions environmental and Engineering Research Institute, Chinese Academy of Sciences,{3., china 3. resource and environment school, lanzhou university,{3., china Institute of Mountain Hazards and environment Chinese Academy of Sciences Chengdu China resource and environment school Lanzhou University Lanzhou China Cold and Arid Regions environmental and Engineering Research Institute Chinese Academy of Sciences Lanzhou China

Since the 1960s, dramatic changes have taken place in land-use patterns characterized by the persistent expansion of cultivated land and a continuous decrease in natural woodland and grassland in the arid inland river basins of china. It is very important to assess the effects of such land-use changes on the hydrological processes so vital for water resource management and sustainable development on the catchment scale. The Maying River catchment, a typical arid inland watershed located in the middle of the Hexi Corridor in northwest china, was the site chosen to investigate the hydrological responses to land-use changes. The annual runoff, base flow, maximum peak flow, and typical seasonal runoff in both spring and autumn flood periods were selected as the variables in the hydrological processes. Statistical-trend analysis and curvilinear regression were utilized to detect the trends in hydrological variables while eliminating the climatic influence. The relationship between cultivated land-use and hydrological variables was analyzed based on four periods of land-use variation data collected since 1965. A runoff model was established composed of two factors, i.e., cultivated land use and precipitation. The impact of land use changes, especially in the large ar- eas of upstream woodland and grassland turned into cultivated lands since 1967, has resulted in a mean annual runoff decrease of 28.12%, a base flow decline of 3..3.%, a drop in the maximum peak discharge of 3..77%, and mean discharge decreases in spring and autumn of 3..05% and 24.87% respectively, of which the contribution of cultivated land expansion to the influence of annual runoff amounts to 77%-80%, with the contribution to the influence of spring discharge being 73.-81%, and that to the influence of base flow reaching 62%-65%. Thus, a rational regulation policy of land use patterns is vitally important to the sustainable use of water resources and the proper development of the entire catchment.

关键词： land-use change, arid inland river catchment, hydrological process, impact, Maying River.

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Indeterminate direction relation model based on fuzzy description framework

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Science china(Technological Sciences) 2008年第S1期51卷 72-80页

作者： LIU YaoLin1,HE JianHua1,YU Yan2 & TANG XinMing3.1 school of resource and environment Science,Wuhan {3.,Wuhan 43.079,china 2 school of resource and environment Engineer,Wuhan {3. of Technology,Wuhan 43.070,china 3.Chinese Academy of Surveying and Mapping,Beijing 10083.china school of resource and environment Science Wuhan University school of resource and environment Engineer Wuhan University of Technology

The indetermination of direction relation is a hot topic for fuzzy GIS researchers. The existing models only study the effects of indetermination of spatial objects,but ignore the uncertainty of direction reference framework. In this paper,first a for-malized representation model of indeterminate spatial objects is designed based on quadruple (x,y,A,μ),then a fuzzy direction reference framework is constructed by revising the cone method,in which the partitions of direction tiles are smooth and continuous,and two neighboring sections are overlapped in the transitional zones with fuzzy method. Grounded on these,a fuzzy description model for indeterminate direction relation is proposed in which the uncertainty of all three parts (source object,reference object and reference frame) is taken into account simultaneously. In the end,case studies are implemented to test the rationality and validity of the model.

关键词： direction relation fuzzy description framework fuzzy representation model uncertainty

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Magnetostratigraphy of Late Cenozoic fossil mammals in the northeastern margin of the Tibetan Plateau

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Science Bulletin 2003年第2期48卷 188-193页

作者： SONG Chunhui1,2,FANG Xiaomin 1,2,GAO Junping1, NIE Junsheng1,YAN Maodu1,3.XU Xianhai1 & SUN Dong1 1. MOE National Laboratory of Western china抯 environmental Systems & College of resource and environment,lanzhou university,lanzhou 73.000,china 2. State Key Laboratory of Loess and Quaternary Geology ,Institute of Earth environment,Chinese Academy of Sciences,Xi抋n 710075, china 3. Department of Geological Sciences,university of Michigan,AnnArbor,MI 48109,USA Univ Arizona Steward Observ Tucson AZ 85721 USA MOE National Laboratory of Western china\'s environmental Systems & College of resource and environment Lanzhou University Lanzhou 730000 China

A number of fossil mammals have been found in the very thick Cenozoic stratigraphy of the Guide Basin in the northeastern margin of the Tibetan *** of these are of great significance in mammal evolution and stratigraphic correla-tion on and around the Tibetan Plateau and North ***,the chronology of these mamals is poorly *** of the mammals will not only place precise age constraints on the mammals,but also provide much inlormation on the related stratigraphy that records the uplift process of the Tibetan *** paleomagnetism of the upper part of the Cenozoic stratigraphy at He'erjia and Lajigai north of Guide County has revealed magnetic chrons that can be correlated to Ganss and 3.n *** the section spanning about 3.16.5 Ma and the *** and third layers of fossil mammals at about 5.25,5.1 and 4.4 Ma,*** of the significant genus Gazella kueitensis and the Chinese elephant Anancus sinensis are firstly constrained at about 5.25 MaBP and 4.4 Ma,*** mammalian evolution and the associated increase in coarse sediments and sedimentation rate may suggest that the northeastern Tibetan Plateau was uplifted rapidly at that time,and the eastern Tibetan Plateau with its neighboring regions was not high enough to stop mammal exchange between the northern and southern sides of the Tibetan Piateau.

关键词： Tibetan Plateau Guide Basin Late Cenozoic stratigra-phy fossil mammals paleomagnetism.

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Variation of peroxidase isoenzyme and biofilm of Phanerochaete chrysosporium in continuous membrane bioreactor for Reactive Brilliant Red X3.B treatment

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Journal of environmental Sciences 2009年第7期21卷 940-947页

作者： GAO Shang, CHEN Cheng, TAO Fang, HUANG Minsheng, MA Lihua, WANG Zhonghua, WU Linhui school of resource and environment Science, East{3. Normal university, Shanghai 200062,{3.. school of resource and environment Science East China Normal University

The influence of a Reactive Brilliant Red X-3. （RBR X-3.） dye on the peroxidase isoenzyme ofPhanerochaete chrysosporium was determined, and the biofilm structure in a white rot fungal continuous membrane bioreactor （MBR） was also investigated by scanning electron microscope （SEM）. The variation of peroxidase isoenzyme and the decolorization rate in the continuous MBR were evaluated. The results showed that the 100 mg/L RBR X-3. could stimulate the production of the peroxidase isoenzyme in the shaking-flask culture. In addition, two new peroxidase isoenzyme bands with relative mobility （Rf） value of 0.27 and 0.28 appeared, but the activity was lower than the blank control of 11 d. In the continuous MBR, the system worked stably during the first 60 d, the main peroxidase isoenzyme bands existed and three new bands with Rf value of 0.10, 0.27, and 0.28 appeared. Meanwhile, the biofilm grew well and the average decolorization rate could reach 90.6%. But the bands of peroxidase isoenzyme decreased rapidly at day 65, only two bands with Rf value 0.24 and 0.26 existed, and the decolorization rate decreased to 78.3.. Therefore, 5 bottles of P. chrysosporium mycelial pellet were added into the MBR, and then the activity of the peroxidase isoenzyme and the decolorization rate had a slight recovery. Finally, the decolorization rate finally decreased to 75.2%. These results contribute to a comprehensive understanding of the variation of peroxidase isoenzyme and biofilm in continuous MBR by white rot fungi.

关键词： Phanerochaete chrysosporium continuous membrane bioreactor Reactive Brilliant Red X3.B peroxidase isoenzyme pattern

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Phytotoxicity of four herbicides on Ceratophyllum demersum,Vallisneria natans and Elodea nuttallii

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Journal of environmental Sciences 2009年第3期21卷 307-312页

作者： PAN Huiyun,LI Xiaolu,XU Xiaohua,GAO Shixiang State Key Laboratory of Pollution Control and resource Reuse,school of the environment,Nanjing {3.,Nanjing 210093.china. State Key Laboratory of Pollution Control and resource Reuse School of the Environment Nanjing University Nanjing 210093 China

The physiological effects of 4 herbicides （butachlor, quinclorac, bensulfuron-methyl and atrazine） on 3.submerged macrophytes （Ceratophyllum demersum, Vallisneria natans and Elodea nuttallii） were tested in laboratory. The variables of the relative growth rate and the photosynthetic pigment content showed that all of the tested herbicides affected the growth of the plants obviously, even at the lowest concentration （0.0001 mg/L）. Except for the C. demersum treated with quinclorac at 0.005 and 0.01 mg/L, the relative growth rates of the plants were inhibited significantly （p 〈 0.01）. Statistical analysis of chlorophyll a （Chl-a） contents was carded out with both the t-test and one-way ANOVA to determine the difference between the treatment and control. The results showed that Chl-a contents of the plants in all treatment groups were affected by herbicides significantly, except for the C. demersum treated with bensulfuron-methyl at 0.0005 mg/L. The decrease in Chl-a content was positively correlated to the dosage of the herbicides in most treatment groups. It was suggested that herbicides in water bodies might potentially affect the growth of aquatic macrophytes. Since the Chl-a content of submerged macrophytes responded to the stress of herbicides sensitively and directly, it could be used as a biomaker in environmental monitoring or in the ecological risk assessment of herbicide contamination.

关键词： phytotoxicity herbicides submerged macrophyte ecological risk assessment

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Influence of Particle Size on Magnetic Properties of Soils in Zhejiang Province, china

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Pedosphere 2000年第1期10卷 81-88页

作者： LU SHENGGAO (College of environment and resource, Zhejiang university, Hangzhou 510029 ({3.)) 浙江大学浙江杭州 310029

The relationship between magnetic properties and particle size of soils derived from metamorphic rock, basalt, granite, Quaternary red clay, limestone and mudstone from Zhejiang Province, East china was studied. Based on the variations of the mass magnetic susceptibility (X), anhysteretic remanent magnetization (ARM), and saturation isothermal remanent magnetization (SIRM) with soil particle size, the relationship could be classified into three groups. For the soils derived from metamorphic rock and basalt, magnetic values were the highest in the gravel and coarse sand fractions and decreased with decreasing soil particle size. The soils derived from sedimentary rock had a bimodal distribution of magnetic values, with peaks in 1-0.5 and 0.005-0.000 5 mm fractions. The soil developed on granite was characterized by a peak of magnetic value in 0.001-0.000 5 mm fractions. Frequency-dependent susceptibility (Xfd ) and ratics of magnetic parameters (ARM/X, SIRM/X and SIRM/ARM) of soil particle fractions showed that variations in ferrimagnetic grain size paralleled those in particle size. Xfd peaked in clay fraction and decreased with increasing particle size, irrespective of soil parent materials. The acquisition curves of IRM and demagnetization parameter of different soil particles indicated that there were different magnetic minerals assemblages in different particle fractions.

关键词： soil particle soil parent material magnetic property Zhejiang Province

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Dynamics of the Coordination of Economy-Society and resource-environment in Shandong Peninsula,china

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Chinese Journal of Population,resources and environment 2012年第3期10卷 62-71页

作者： Han Rongqing Zhao Minghua Institute of Geographic Sciences and Natural resources Research CASBeijing 100101China Graduate university of Chinese Academy of Sciences Beijing 100049China Population Recourses and Environment College of Shandong Normal UniversityJinan Shandong 250014China

Shandong Peninsula,as a more developed region in Shandong Province even the east coast of china,is facing challenges from resources and environment *** paper tried to track and assess the coordination status and the dynamic between resource-environment and economy-society systems in Shandong Peninsula during 2001-2008 in order to provide decision support for regional *** appraisal index system was built including five aspects of harmony degree(A),sustainability degree(B),opening degree(C),stability degree(D) and controllability degree(E).The results showed that:1) The coordination level of resource-environment and economy-society in Shandong Peninsula has continuously grown,and it has undergone three stages:no coordinated degree(2001-2002),weak coordinated degree(2003.2006) and basically coordinated degree(2007-2008).2) Five indexes of criterion hierarchy also increased overall,but each index showed different *** degree,sustainability degree and opening degree rose all the time,while stability degree and controllability degree alternately rose and *** improvement of controllability degree was the slowest.3. The aggravating trend of environmental pollution was slowing *** economic growth was driven by industrial growth and urbanization typically and investment was still the main force to pull the regional economic *** the same time,technology and education were becoming more and more important for economic *** level of foreign capital utility declined and the geographical advantage of Shandong Peninsula was *** some characteristics of knowledge economy were *** resources become the main constraint factor of fast development in Shandong *** is necessary to further strengthen the coordination ability of government on regional sustainable development.

关键词： dynamics coordination of resource-environment andeconomy-society Shandong Peninsula

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Adsorption of surfactants onto acrylic ester resins with different pore size distribution

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Science china Chemistry 2006年第5期49卷 445-453页

作者： YANG Weiben1,2,3.LI Aimin1,3.CAI Jianguo1,3.MENG Guanhua1,3.& ZHANG Quanxing1,3.1. State Key Laboratory of Pollution Control and resource Reuse,school of the environment,Nanjing {3.,Nanjing 210093.china 2. Nanjing College of Chemical Technology,Nanjing 210048,china 3. Jiangsu Engineering & Technology Research Center for Organic Toxicant Control and resource Reuse,Nanjing 21003.,china State Key Laboratory of Pollution Control and resource Reuse School of the Environment Nanjing University Nanjing China Nanjing College of Chemical Technology Nanjing China Jiangsu Engineering & Technology Research Center for Organic Toxicant Control and resource Reuse Nanjing China

In this study, a series of acrylic ester resins with different pore size distribution were prepared successfully by varying the type and the amount of pore-forming agents. In order to inves-tigate the adsorption behavior and mechanism of surfactants on acrylic ester resins, three kinds of surfactants were utilized as adsorbates that were sodium 6-dodecyl benzenesulfonate (6-NaDBS), sodium 1-dodecyl benzene sulfonate (1-NaDBS) and sodium 1-dodecyl sulfonate, respectively. It was observed that the surface area was available in a particular pore size and an appropriate pore size of resins appeared to be more important for the adsorption of surfactants. As compared to commercial acrylic ester resins XAD-7 and HP2MG, 50# and 3.# resins exhibited more excellent adsorption properties toward 1-NaDBS and 6-NaDBS. The experimental equilibrium data were fitted to the Langmuir, and double-Langmuir models. Two models provided very good fittings for all resins over the temperature range studied. The investigation indicated that electrostatic attraction and hydrogen bond between resins and surfactants were the main forces and had an obvious effect on adsorption proc-ess.

关键词： acrylic ester resin, surfactant, adsorption, pore size distribution, isotherm.

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Microwave photocatalytic degradation of Rhodamine B using TiO_2 supported on activated carbon:Mechanism implication

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Journal of environmental Sciences 2009年第2期21卷 268-272页

作者： HE Zhong,YANG Shaogui,JU Yongming,SUN Cheng State Key Laboratory of Pollution Control and resource Reuse,school of the environment,Nanjing {3.,Nanjing 210093.china. State Key Laboratory of Pollution Control and resource Reuse School of the Environment Nanjing University Nanjing 210093 China

The photocatalytic degradation of Rhodamine B （RhB） was carried out using TiO2 supported on activated carbon （TiO2-AC） under microwave irradiation. Composite catalyst TiO2-AC was prepared and characterized using X-ray diffraction （XRD）, transmission electron microscopy （TEM） and Brunauer-Emmett-Teller （BET）. In the process of microwave-enhanced photocatalysis （MPC）, RhB （3. mg/L） was almost completely decoloured in 10 min, and the mineralization efficiency was 96.0% in 20 min. The reaction rate constant of RhB in MPC using TiO2-AC by pseudo first-order reaction kinetics was 4.16 times of that using Degussa P25. Additionally, according to gas chromatography/mass spectrometry （GC/MS） and liquid chromatography/mass spectrometry （LC/MS） identification, the major intermediates of RhB in MPC included two kinds of N-de-ethylation intermediates （N,N-diethyl-N＇-ethyl-rhodamine （DER））, oxalic acid, malonic acid, snccinic acid, and phthalic acid, maleic acid, 3.nitrobenzoic acid, and so on. The degradation of RhB in MPC was mainly attributed to the destruction of the conjugated structure, and then the intermediates transformed to acid molecules which were mineralized to water and carbon dioxide.

关键词： microwave photocatalytic WiO2, activated carbon Rhodamine B degradation mechanism

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