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SPATIO-TEMPORAL change OF DROUGHT disaster IN{2. IN RECENT FIFTY YEARS

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natural disaster Reduction in{2. 2003年第1期 11-17页

作者： Wang Jingai 1,2., Sun Heng 1, Xu Wei 1 and Zhou Jinju 1 (1. Department of Resource & Environment Science, beijing normal university, beijing 100875,{2. 2. key laboratory of environmental change and natural disaster, ministry of education of{2., beijing normal university, beijing 100875,{2.) SunHui

In this paper, a drought disaster database, based on information from Chinese provincial newspaper, is established. And the spatio temporal pattern of drought disaster from 1949 to 2.00 is reconstructed by using technology of digital mapping. The results show that the spatial pattern of drought disaster takes on discrepancy between the east and west of china, the serious disaster area lies in the north, especially in the west of Heilongjiang, the center of Inner Mongolia, the north of Hebei and Shaanxi, Ningxia; in the south of the country, drought disaster area lies in Anhui, Hubei, Hunan, Jiangxi, Henan, and Guizhou, the east of Sichuan, the center～east of Yunnan. The distribution of drought disaster in china has the tendency of extension to the west. Dynamic change of drought disaster takes on discrepancy between the south and north of the country. The amount of the drought disaster in the north of the Yangtze River is increasing, while the south is decreasing generally or changing invisibly.

关键词： drought disaster amount of the disaster spatio temporal change

Redevelopment of liftoff rates of saltating sand grains based on a simple optimization model

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Science china Earth Sciences 2010年第4期53卷 568-574页

作者： CHENG Hong & ZOU XueYong State key laboratory of Earth Surface Processes and Resource Ecology,beijing normal university,beijing 100875,china MOE Engineering Center of Desertification and Blown-sand Control,beijing normal university,beijing 100875,china key laboratory of environmental change and natural disaster of the ministry of education of china,beijing normal university,beijing 100875,china 1. State key laboratory of Earth Surface Processes and Resource Ecology Beijing Normal University Beijing 100875 China2. MOE Engineering Center of Desertification and Blown-sand Control Beijing Normal University Beijing 100875 China3. Key Laboratory of Environmental Change and Natural Disaster of the Ministry of Education of China Beijing Normal University Beijing 100875 China

This paper is a redevelopment result of liftoff rates of saltating sand grains based on our previous *** sand flow is a complex multi-phase flow because of a special two-phase gas-solid flow near ground *** extensive research on the movement of blowing sand,no model fully characterizes aeolian sand flow,and large differences often exist between simulations of aeolian sand movement and field *** key problem is a few of sufficient research on liftoff rates of saltating sand grains(also called the number of liftoff sand grains per unit time and per unit bed area).It is necessary to re-search in advance liftoff rates of saltating sand *** redeveloped liftoff rates of saltating sand grains by establishing an optimization model based on the flux of aeolian sand flow at different heights of the sampler in wind tunnel and the simulated capture of saltating sand grains by different heights of the sampler that are from different liftoff position(distance from the sampler) in order to revise previous inversion condition of liftoff rates of saltating sand *** rates increased rapidly with increasing wind *** frictional wind velocities of u=0.67,0.77,0.82.0.83,and 0.87 m s-1,liftoff rates were 3840,954502.52.5114,5499407,and 76962.1 sand grain s-1 m-2.*** rates could be expressed as the square of the instantaneous frictional wind velocity and a constant(0.663) that differs from the critical(threshold) frictional wind velocity at which saltation *** our results require additional experimental validation and the simple optimization model must be improved,they nonetheless provide a strong basis for future research.

关键词： liftoff rates of saltating sand grains optimization model wind tunnel two-phase gas-solid flow

Edaphic factors determining variation of two ecotypes of Leymus chinensis in North china

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Progress in natural Science:Materials International 2006年第11期16卷 1150-1155页

作者： ZHOU Chan~1 and YANG Yunfei~2.*(1. MOE key laboratory of {2. change and natural disasters, College of Resources Science and Technology, beijing normal university, beijing 100875, china 2. key laboratory of Vegetation Ecology, ministry of education, Institute of Grassland Science, Northeast {12. university, Changchun 13002., china) [a]MOE key laboratory of {2. change and natural disasters College of Resources Science and Technology Beijing Normal University Beijing China [b]key laboratory of Vegetation Ecology Ministry of Education Institute of Grassland Science Northeast Normal University Changchun China

To identify ecotypic variation of L. chinensis, the physiological characteristics and environmental factors were measured and assessed for grey-green and yellow-green ecotypes of L. chinensis grown in the salt-alkalized and aeolian sandy soils. Although both ecotypes presented a similar salt-alkaline tolerance under the experimental conditions, they differed in several aspects. The L. chinensis grown in the aeolian sandy soils had higher water potential and chlorophyll content and lower proline content in their leaves than those grown in the salt-alkalized habitat, and the grey-green ecotype of L. chinensis in both types of soils had higher water potential, chlorophyll and proline contents than the yellow-green ecotype. Besides, grey-green ecotypes had higher salt-alkaline tolerance than the yellow-green ecotype. The stepwise regression analysis showed that soil conductance and pH value were the main ecological factors affecting the physiology of L. chinensis. From the natural distribution of the two ecotypes, we considered that salt-alkaline in the soils is the leading factor in determining ecotypic variation of L. chinensis. The two ecotypes were first named grey-green and yellow-green ecotypes respectively.

关键词： L.chinensis ecotype adaptability variation ecological factor salt-alkaline in soil.

Developing land use scenario dynamics model by the integration of system dynamics model and cellular automata model

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Science china Earth Sciences 2005年第11期48卷 1979-1989页

作者： HE Chunyang, SHI Peijun, CHEN Jin, Li Xiaobing, PAN Yaozhong, LI Jing, LI Yuechen & LI Jinggang key laboratory of {2. change and natural disaster, ministry of education of china, beijing normal university College of Resources Science & Technology, beijing normal university, beijing 100875, china 1. key laboratory of {2. change and natural disaster Ministry of Education of China Beijing Normal University China 2. College of Resources Science & Technology Beijing Normal University 100875 Beijing China

Modeling land use scenario changes and its potential impacts on the structure and function of the ecosystem in the typical regions are helpful to understanding the interactive mechanism between land use system and ecological system. A Land Use Scenario Dynamics (LUSD) model by the integration of System Dynamics (SD) model and Cellular Automata (CA) model is developed with land use scenario changes in northern{2. in the next 2. years simulated in this paper. The basic idea of LUSD model is to simulate the land use scenario de-mands by using SD model at first, then allocate the land use scenario patterns at the local scale with the considerations of land use suitability, inheritance ability and neighborhood effect by using CA model to satisfy the balance between land use scenario demands and supply. The application of LUSD model in northern{2. suggests that the model has the ability to reflect the complex behavior of land use system at different scales to some extent and is a useful tool for assessing the potential impacts of land use system on ecological system. In addition, the simulated results also indicate that obvious land use changes will take place in the farming-pastoral zone of northern{2. in the next 2. years with cultivated land and urban land being the most active land use types.

关键词： system dynamics, cellular automata, scenario, land use, model

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{2. 3 key laboratory of environmental change and natural disaster of ministry of education of china 4 College of Resources Science & Technology,{2.,{12., china College of Geography and Remote Sensing Beijing 100048 China key laboratory of {2. 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

Effects of chronic exposure to nonylphenol on locomotor activity and social behavior in zebrafish(Danio rerio)

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Journal of environmental Sciences 2010年第9期22卷 1435-1440页

作者： Jigang Xia,Cuijuan Niu ,Xuejiao Pei ministry of education key {2. of Biodiversity Science and Ecological Engineering,College of Life Sciences,beijing normal university,100875 beijing,china. [a] ministry of education key {2. of Biodiversity Science Ecological Engineering College of Life Sciences Beijing Normal University 100875 Beijing China

Nonylphenol （NP）, a xenoestrogen ubiquitously found in aquatic ecosystems, is of high environmental concern. The present work assessed the effects of exposure to NP on locomotor activity and social behavior in male and female zebrafish （Danio rerio）, to evaluate the possible hazard of NP to fish behavior and to pursue a potential biomarker of NP contamination. Fish were randomly divided into six groups. Five groups were receiving 0.1, 1, 10, 50 and 100 μg/L nominal concentrations of NP for 60 days, respectively. A sixth control group was given the same treatment as the other five groups, but no NP. Locomotor activity, aggressive behavior, group preference and leaving shoal were examined. NP exposure showed marked influence on locomotor activity of the male zebrafish, whereas that of the female was not significantly affected by NP. Aggressive behavior and group preference were significantly affected by NP exposure in both male and female groups. Locomotor activity and aggressive behavior of the male and group preference of both male and female zebrafish were clearly inhibited at 100 μg/L NP. No significant alteration in leaving shoal was observed under NP exposure. The results suggested that changes in locomotor activity and aggressive behavior of the male and group preference of both male and female may be used as an ecologically relevant integrative biomarker of NP contamination.

关键词： chronic toxicity nonylphenol biomarker zebrafish

Flooding 1990s along the Yangtze River, has it concern of global warming?

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Journal of Geographical Sciences 2001年第1期11卷 43-52页

作者： GONG Dao-yi1, ZHU Jin-hong2. WANG Shao-wu2.(1. key laboratory of {2. change and natural disaster, Institute of Resources Science, beijing normal university, beijing 100875, china 2. Department of Geophysics, Peking university, beijing 100871, key laboratory of {2. change and natural disaster Institute of Resources Science Beijing Normal University Beijing China Department of Geophysics Peking University Beijing China

There were a series of severe floods along the middle to lower reaches of the Yangtze River (Changjiang River) in china during the 1990s. The extensive summer (June, July and August) precipitation is mostly responsible for the flooding. The summer rainfall in the 1980s and the 1990s is much higher than that in the previous 3 decades. The means for 1990–1999 is +87.62.mm above normal, marked the 1990s the wettest decade since the 1950s. Six stations with a time span of 1880–1999 are selected to establish century-long rainfall series. This series also shows that the 1990s is the wettest decade during the last 12. years. In the wettest 12.years, four occurred in the 1990s (1991, 1996, 1998 and 1999). Both global and china’s temperature show there is a relative lower air temperature during the 1960–1970s, and a rapid warming in the 1980–1990s. Comparisons of rainfall between 1960–1979 and 1980–1999 show there are dramatic changes. In the cold period 1960–1979, the summer rainfall along the Yangtze River is 3.8 % to 4.7 % below the normal, during the warm period 1980–1999, over 8.4 % to 18.2.% of summer rainfall occurs. Over the whole eastern china, the summer rainfall shows opposite spatial patterns from the 1960–1970s to 1980–1990s. The consistent trend toward more rainfall with global warming is also presented by the greenhouse scenario modeling. A millennial Drought/flood Index for the middle to lower reaches of the Yangtze River showed that although the surplus summer rainfall in the 1990s is the severest during the past 150 years, it is not outstanding in the context of past millennium. Power spectra of the Drought/flood Index show significant interdecadal periods at 33.3 and 11.8 years. Thus, both the natural interdecadal variations and the global warming may play important roles in the frequent floods witnessed during the last two decades.

关键词： summer rainfall Yangtze River global warming interdecadal variation

^(137)Cs tracing of lacustrine sediments in the Dalian Lake,Qinghai Province,china

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Chinese Science Bulletin 2001年第S1期46卷 83-87页

作者： VAN Ping, DONG Guangrong & DONG Zhibaochina Certer of Desert Research at beijing normal university, {2.100875, china:key laboratory of environmental change and natural disaster, the ministry of education of china, beijing normal university, beijing 100875, china Cold and Arid Regions environmental and Engineering Research Institute, Chinese Academy of Sciences, Lanzhou 730000, china 1. china Certer of Desert Research at beijing normal university 100875 Beijing China 2. key laboratory of environmental change and natural disaster The Ministry of Education of China Beijing Normal University 100875 Beijing China 3. Cold and Arid Regions environmental and Engineering Research Institute Chinese Academy of Sciences 730000 Lanzhou China

Based upon the analysis of Cs and grain-size parameters, the total amounts of 137Cs deposition by wind and water in the Dalian Lake of Gonghe Basin, Qinghai Province are defined. The vertical profile of 137Cs in the lacustrine sediments exhibits three 137Cs activity maxima and one minimum. The major maximum corresponds to the global I37Cs fallout in 1963; the two secondary maxima correspond to the leakage of the Chernobyl reactor in 1986 and complete desiccation of the lake in 1994, respectively. The minimum corresponds to aeolian deposition caused by extensive reclamation in the late 1980s and early 1990s. The 137Cs data set was used to evaluate average sedimentation rate of the Dalian Lake since 1963. The deposition was stable in 1963-1986 and 1994-1998, and it was rapid during 1986?994. This preliminary study reveals that l37Cs has the same potential to trace environmental changes introduce by human interference in arid/semiarid regions as in humid regions.

关键词： 137Cs technique Dalian Lake sedimentation rate.

Estimation of regional evapotranspiration over Northwest china using remote sensing

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Journal of Geographical Sciences 2001年第2期11卷 140-148页

作者： CHEN Yun-hao, LI Xiao-bing, SHI Pei-jun (Institute of Resources Science, beijing normal university, key {2. of environmental change and natural disaster, ministry of education of china, beijing 100875, china) Institute of Resources Science Beijing Normal University Key Laboratory of Environmental Change and Natural Disaster Ministry of Education of China

It is a very complicated problem to estimate evapotranspiration (ET) over a large area of land surface. In this paper, the evapotranspiration estimation models for dense vegetation and bare soil are presented, based on the information of parameters like vegetation cover-degree and surface albedo. Combined with vegetation cover-degree data, a model for regional evapotranspiration estimation over the heterogeneous landscape is derived. Through a case study using remote sensing data over Northwest china, the accuracy of the model for regional evapotranspiration estimation is checked. The result shows that the accuracy of the model is satisfactory. The features of evapotranspiration over Northwest china are also discussed with the application of the model.

关键词： evapotranspiration remote sensing vegetation cover-degree Northwest china