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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 Wuhan China school of resource and environment Engineer Wuhan University of Technology Wuhan China Chinese Academy of Surveying and Mapping Beijing China

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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Pentacyclic triterpenoid ketones in peat from Gannan Marsh,china

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Chinese Science Bulletin 2001年第17期46卷 1433-1436页

作者： DUAN Yilanzhou Institute of Geology, Chinese Academy of Sciences, lanzhou 730000, china lanzhou Institute of Geology Chinese Academy of Sciences Lanzhou China

Abundant terrigenous triterpenoid ketones and a series of hopanoid ketones were detected in a peat sample from the recent Gannan Marsh. The identifications of pen-tacyclic triterpenoid ketones are discussed in detail. Based on the compositional features of pentacyclic triterpenoid ketones in the sample, it is proposed that terrigenous triterpenoid kentones originate directly from organisms or are diagenetic oxidation products of their alcohols, and hopanoid ketones are formed from hopanoids (e.g. hopanoid alcohols and hopenes) by chemical and biochemical processes. These data provide evidence for the applied studies of pentacyclic triterpenoid ketones as biomarker compounds.

关键词： Gannan Marsh peat pentacyclic triterpenoid ketones identification biochemistry.

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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 730000,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 MOE National Laboratory of Western china’s environmental Systems & College of resource and environment Lanzhou University Lanzhou China State Key Laboratory of Loess and Quaternary Geology Institute of Earth Environment Chinese Academy of Sciences Xi’an China Department of Geological Sciences University of Michigan Ann Arbor USA

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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Evidence from carbon isotope measurements for biological origins of individual long-chain n-alkanes in sediments from the Nansha Sea,china

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Chinese Science Bulletin 2002年第7期47卷 578-581页

作者： DUAN Yi & WANG ZhipingState Key Laboratory of Gas Geochemistry, lanzhou Institute of Geology, Chinese Academy of Sciences, lanzhou 730000, china Institute of {3.al Science, Beijing Normal university, Beijing 100875, china State Key Laboratory of Gas Geochemistry Lanzhou Institute of Geology Chinese Academy of Sciences Lanzhou China Institute of environmental Science Beijing Normal University Beijing China

Carbon isotopes are measured for individual long-chain n-alkanes in sediments from the Nansha Sea. The features of carbon isotopic compositions of individual n-alkanes and their origins are studied. The results show that the long-chain n-alkanes have a light carbon isotopic composition and a genetic feature of mixing sources, and low-latitude higher plants and microbes are considered to be their main end member sources. Based on the abundances and carbon isotopic compositions of individual n-alkanes, the fractional contributions of the two end member sources to individual n-alkanes are quantitatively calculated by using a mixing model. The obtained data indicate that the fractional contributions of the two biological sources are different in the three samples. A trend is that the contribution of microbes increases with the depth. These results provide the theory basis and quantitatively studied method for carbon isotopic applied research of individual n-alkanes.

关键词： modern marine sediment individual n-alkane carbon isotopic composition biological source.

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Offline experiment of land surface processes in Qinghai-Xizang Plateau

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Science china Earth Sciences 2004年第Z1期47卷 115-121页

作者： ZHANG Yanwu, LU Shihua, FENG Qi, HUANG Jing & HU ZeyongCold and Arid Regions environmental and Engineering Institute, Chinese Academy of Sciences, lanzhou 730000, china {3. environment College, lanzhou university, lanzhou 730000, china

The observational data of Beiluhe test of the Qinghai-Xizang railway in June 2002 are used as forcing field of the surface model to study the simulation performance in Qinghai-Xizang Plateau. The simulation result shows that the model (NCAR/LSM) can present the surface character tendency reasonably under observation forcing. In NCAR/LSM, the descriptions of the surface vegetation type in Qinghai-Xizang Plateau have much difference to what is actually happening. According to the actual characteristic of the surface, we define the grassland vegetation coverage rate is 0.6, and the vegetation canopy is 0.15 m, and the displacement height is 0.10 m. Compared the results with the old model's parameter in experiment, we find that the simulation air (2 m) temperature and the ground temperature are close to those of the observation, and the simulation temperature of peak value is better, and the simulation flux of the ground is sure to be improved too. So, if the surface and vegetation parameters are revised in LSM model, the simulation capability of the land surface process model can be improved effectively in Qinghai-Xizang Plateau.

关键词： Qinghai-Xizang Plateau land surface processes NCAR/LSM.

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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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Theorem of turbulent intensity and macroscopic mechanism of the turbulence development

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Science china Earth Sciences 2007年第5期50卷 789-800页

作者： HU YinQiao1,2, CHEN JinBei3.4 & ZUO HongChao2 1 Gansu Province Key laboratory of Arid Climatic Change and Reducing Disaster, Cold and Arid Regions environment and Engi- neering Institute, Chinese Academy of Sciences, lanzhou 730000, china 2 State Key Laboratory of Atmospheric Boundary Layer Physics and Atmospheric Chemistry (LAPC), Beijing 100029, china 3.Atmospheric Science College, lanzhou university, lanzhou 730000, china 4 resource environment Department, lanzhou Agriculture university, lanzhou 73.060, china Gansu Province Key laboratory of Arid Climatic Change and Reducing Disaster Cold and Arid Regions Environment and Engineering Institute Chinese Academy of Sciences Lanzhou 730000 China State Key Laboratory of Atmospheric Boundary Layer Physics and Atmospheric Chemistry(LAPC) Beijing 100029China Atmospheric Science College Lanzhou University Lanzhou 730000 China resource environment Department Lanzhou Agriculture University Lanzhou 730060 China State Key Laboratory of Atmospheric Boundary Layer Physics and Atmospheric Chemistry LAPC Beijing 100029 China

Turbulence is one of the most common nature phenomena in everyday experience, but that is not adequately understood yet. This article reviews the history and present state of development of the turbulence theory and indicates the necessity to probe into the turbulent features and mechanism with the different methods at different levels. Therefore this article proves a theorem of turbulent transpor- tation and a theorem of turbulent intensity by using the theory of the nonequilibrium thermodynamics, and that the Reynolds turbulence and the Rayleigh-Bénard turbulence are united in the theorems of the turbulent intensity and the turbulent transportation. The macroscopic cause of the development of fluid turbulence is a result from shearing effect of the velocity together with the temperature, which is also the macroscopic cause of the stretch and fold of trajectory in the phase space of turbulent field. And it is proved by the observed data of atmosphere that the phenomenological coefficient of turbulent in- tensity is not only a function of the velocity shear but also a function of temperature shear, viz the sta- bility of temperature stratification, in the atmosphere. Accordingly, authenticity of the theorem, which is proved by the theory of nonequilibrium thermodynamics, of turbulent intensity is testified by the facts of observational experiment.

关键词： turbulence nonequilibrium thermodynamics linear thermodynamics atmosphere boundary layer Reynolds turbulence Rayleigh-Bénard turbulence

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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 Shanghai 200062 China

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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