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Spatial distribution regularity and influence factors of population density in the LRGR

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science Bulletin 2007年第S2期 90-97页

作者： SONG GuoBao~(1,2) LI ZhengHai~(1,3+) BAO YaJing~1 L HaiYan~4 GAO JiXi~3 WANG HaiMei~5 XU Tian~6 CHENG Yan~7 1 Institute of Bio-resources and Environment,college of Life science,Dalian Nationalities university,Dalian 116600,china 2 college of resources science & technology,beijing normal university,beijing 100875,china 3 Innovation Base of Regional Ecology,Chinese Research Academy of Environmental sciences,beijing 100012,china 4 Institute of Agricultural resources and Regional Planning,Chinese Academy of Agricultural sciences,beijing 100081,china 5 Inner Mongolia Municipality Observatory,Huhhot 010051,china 6 college of Life science,Inner Mongolia university,Huhhot 010021,china 7 college of Ecological Environment,Inner Mongolia Agricultural university,Huhhot 010018,china

Combining GIS measures and statistic methods,this paper selects the physiographic factors and climatic factors to study the influencing strength and its functional forms of all factors on population density in the *** addition,this paper simulates the status of population density distribution in the LRGR with the factors influencing the population density *** findings indicate the following circumstances:(1)All natural factors have influence on the spatial pattern of population density in the LRGR,but the influencing extent and forms are quite *** factors and traffic network density have great influence on population density,while such factors as temperature and precipitation have little influence on population *** relationship between the popula- tion density and the altitude and traffic network density assumes the negative and positive linear cor- relation trends,while the influence of water system density and slope appears to be the exponential function and logarithmic function separately.(2)The population is scattered throughout LRGR and takes on such features as integral scattering and local concentration because of the influence of natural ***,a high population density belt has been formed in the middle of LRGR,and a high population density patch comes into being in the south of LRGR.(3)There is a good linear re- gression relationship between population density and human activity index(HAI)in the LRGR,which reflects that population density can present the artificial disturbance on natural ecosystem in the LRGR. (4)The increase of population density leads to the decrease of NDVI index.

关键词： population density artificial disturbance vegetation coverage physiographic factor LRGR

Study on the spatial differences and its time lag effect on climatic factors of the vegetation in the Longitudinal Range-Gorge Region

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science Bulletin 2007年第S2期 42-49页

作者： BAO YaJing~1 SONG GuoBao~(1,2) LI ZhengHai~(1,3) GAO JiXi~3 L HaiYan~4 WANG HaiMei~5 CHENG Yan~6 XU Tian~7 1 Institute of Bio-resources and Environment,college of Life science,Dalian Nationalities university,Dalian 116600,china 2 college of resources science and technology,beijing normal university,beijing 100875,china 3 Innovation Base of Regional Ecology,Chinese Research Academy of Environmental sciences,beijing 100012,china 4 Institute of Agricultural resources and Regional Planning,Chinese Academy of Agricultural sciences,beijing 100081,china 5 Inner Mongolia Municipality Observatory,Huhhot 010051,china 6 college of Ecological Environment,Inner Mongolia Agricultural university,Huhhot 010018,china 7 college of Life science,Inner Mongolia university,Huhhot 010021,china

This article analyzes the correlation of NDVI and two meteorological data including temperature and precipitation,and probes the spetial pattern of responding sensitivity of the vegetation to temperature and precipitation *** constructing the NDVIrindex,the relation between vegetation cover and land use in the Longitudinal Range-Gorge Region（LRGR）is *** conclusion is as follows:（1） The time lag effect that vegetation responds to temperature and precipitation change is ***- ferent regions have different delay time corresponding to maximum correlation *** to response time of precipitation and temperature combination,three kinds of temperature-precipi- tation forms are defined,namely,precipitation and temperature in the same time,precipitation prior to temperature and temperature prior to precipitation.（2）The spatial distribution of sensitivity,of which vegetation responses to temperature,is characterized by several high and low scattered correlation *** from temperature,two insensitive regions and two sensitive belts are formed to pre- sent the response of vegetation to precipitation.（3）The NDVIris constructed,which can perfectly re- flect the corresponding relationship between meteorological factors and land use condition in the LRGR.

关键词： land cover meteorological factors effect of time lag spatial correlation population density Longitudinal Range-Gorge Region(LRGR)

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 Environmental Change and Natural Disaster, Ministry of Education of china, beijing normal university college of resources science & technology, beijing normal university, beijing 100875, china Key Laboratory of Environmental Change and Natural Disaster Ministry of Education of China Beijing Normal University China college of resources science & technology Beijing Normal University 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 china in the next 20 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 china 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 china in the next 20 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

Scenario simulation and forecast of land use/cover in northern china

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Chinese science Bulletin 2008年第9期53卷 1401-1412页

作者： LI YueChen 1,2,3 & HE ChunYang 3 1 college of Geographical science, Chongqing normal university, Chongqing 400047, china 2 college of resources and Environmental science, Chongqing university, Chongqing 400044, china 3 college of resources science & technology, beijing normal university, beijing 100875, china college of Geographical science Chongqing Normal University Chongqing China college of resources and Environmental science Chongqing University Chongqing China college of resources science & technology Beijing Normal University Beijing China

Modeling land use/cover scenario changes and its potential impacts on structure and functions of ecosystem in typical regions are helpful to understanding the interactive mechanism between land use/cover system and ecosystem. Based on the analysis of the existing land use/cover simulation and forecast models, a land use/cover scenario dynamics model by the integration of System Dynamics (SD) model, Back Propagation Neural Network (BPNN) and Cellular Automata (CA) model is developed with land use/cover scenario changes in northern china in the next 30 years and simulated in this paper. The model is to simulate the land use/cover scenario demands by using a SD model at first, and then allocating the land use scenario patterns at the local scale with the considerations of land use/cover suitability, inheritance ability and neighborhood effect by using BPNN-CA model to satisfy the balance between land use/cover scenario demands and supplies. It integrates the advantages of SD, BPNN and CA. Macro-driving factors and the micro-spatial pattern are also fully taken into account. The BPNN simplifies the identification of the factors’ weights used in CA model and improves the reliability of the simulation results. The simulation accuracy of the model developed in this paper was found to be about 74%. It suggests that the model has the ability to reflect the complexity of land use/cover system at different scales to some extent and it is a useful tool for assessing the potential impacts of land use system on ecosystem. The simulated results also indicate that the urban land, water area and forest will increase significantly, and farmland and unable land will decrease gradually. Obvious land use/cover changes will take place in the farming-pastoral zone and the southeast area of northern china.

关键词：土地利用中国北方细胞自动机系统动力学

Development and application of ergodicity model with FRCM and FLAR for hydrological process

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science china(Technological sciences) 2009年第2期52卷 379-386页

作者： WANG HongRui1, FENG QiLei2, LIN Xin3 & ZENG WenYi4 1 college of Water science, Key Laboratory for Water and Sediment sciences of the Ministry of Education, beijing normal university, beijing 100875, china 2 School of science, beijing Institute of Education, beijing 100011, china 3 School of Mathematical sciences, beijing normal university, beijing 100875, china 4 college of Information science and technology, beijing normal university, beijing 100875, china college of Water science Key Laboratory for Water and Sediment Sciences of the Ministry of Education Beijing Normal University Beijing China School of science Beijing Institute of Education Beijing China School of Mathematical sciences Beijing Normal University Beijing China college of Information science and technology Beijing Normal University Beijing China

In this paper, a new ergodic property analysis model of hydrological process is proposed based on fuzzy-rough c-means clustering (FRCM), autocorrelogram, and fuzzy least absolute regression (FLAR). A precipitation time series (1951―2004) from Shanghai Hydrology Station is then analyzed with the model. The results show that the precipitation time series of April, May, June, and September has er-godic property. We conclude that in the long run, the precipitation of April, May, June, and September will not keep decreasing; it will converge to its mean value in some period.

关键词： hydrological process ergodic autocorrelogram fuzzy-rough c-means clustering fuzzy least absolute regression

The toxicity of Cu^(2+) to Microcystis aeruginosa using dielectric spectroscopy

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science china Chemistry 2010年第3期53卷 631-636页

作者： YU YanLi1,BAI Wei1,ZHAO KongShuang1& ZHOU YunLong2 1college of Chemistry,beijing normal university,beijing 100875,china 2college of Life science,beijing normal university,beijing 100875,china college of Chemistry Beijing Normal University Beijing China college of Life science Beijing Normal University Beijing China

Dielectric spectroscopy(DS) was utilized to investigate the toxicity of the Cu2+ solution to Microcystis *** was found that 0.04 mM Cu2+ had no effect on dielectric increment,whereas the Cu2+ concentrations above 0.1 mM decreased the value of Δε/Δε *** toxic effect of Cu2+ on *** cells was time-dependent and *** was a threshold concentration between 0.04 mM and 0.1 mM,which affected the cell membrane,suggesting that Cu2+ at the concentrations higher than 0.1 mM caused serious plasmalemma damage to *** *** addition of 1 mM Ca2+ or Mg2+ did not protect *** cells from 1 mM Cu2+ *** study demonstrates that DS monitors cell biomass facilitating observation of the toxic effects of metal ions.

关键词： Microcystis aeruginosa dielectric spectroscopy dielectric increment cupric ion toxicity

ENERGY FLOWS IN COMPLEX ECOLOGICAL SYSTEMS:A REVIEW

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Journal of Systems science & Complexity 2009年第3期22卷 345-359页

作者： Jiang ZHANG Department of Systems science,School of Management,beijing normal university,beijing 100875,china. Department of Systems science School of Management Beijing Normal University Beijing China

Energy flow drives the complex systems to *** allometric scaling as the universalenergy flow pattern has been found in different scales of ecological *** reflects the generalpower law relationship between flow and *** underlying mechanisms of energy flow patterns areexplained as the branching transportation networks which can be regarded as the result of systematicoptimization of a biological target under *** flows in the ecological system may bemodelled by the food web model and population dynamics on the *** paper reviews thelatest progress on the energy flow patterns,explanatory models for the allometric scaling and modellingapproach of flow and network evolution dynamics in ***,the possibility of generalizingthese flow patterns,modelling approaches to other complex systems is discussed.

关键词： Allometric scaling energy flow flows in complex systems food web.

Functional central limit theorem for super α-stable processes

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science china Mathematics 2004年第6期47卷 874-881页

作者： HONG WenmingDepartment of Mathematics, beijing normal university, beijing 100875, china Department of Mathematics Beijing Normal University Beijing China

A functional central limit theorem is proved for the centered occupation time process of the super α-stable processes in the finite dimensional distribution sense. For the intermediate dimensions α 2α (0 2), the limiting process is a Gaussian process, whose covariance is specified; for the critical dimension d= 2α and higher dimensions d 2α, the limiting process is Brownian motion.

关键词： super α-stable processes occupation time central limit theorem evolution equation

On asymptotics of t-type regression estimation in multiple linear model

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science china Mathematics 2004年第4期47卷 628-639页

作者： GUI HengjianDepartment of Mathematics, beijing normal university, beijing 100875, china Department of Mathematics Beijing Normal University Beijing China

We consider a robust estimator (t-type regression estimator) of multiple linear regression model by maximizing marginal likelihood of a scaled t-type error *** marginal likelihood can also be applied to the de-correlated response when the withinsubject correlation can be consistently estimated from an initial estimate of the model based on the independent working assumption. This paper shows that such a t-type estimator is consistent.

关键词： t-type regression estimator, M-estimator, one-step estimate, consistency, asymptotic normality.