Loading...

Table of Content

    25 September 2007, Volume 26 Issue 5 Previous Issue    Next Issue
    Climate and Global Change
    The response of vegetation dynamics to climate change in the southwestern karst region of China since the early 1980s
    MENG Ji-jun, WANG Jun
    2007, 26 (5):  857-866.  doi: 10.11821/yj2007050001
    Abstract ( )   PDF (683KB) ( )   Save
    The relationship between climate change and vegetation dynamics has been identified by recent studies in global and regional scales. Based on previous researches and AVHRR GIMMS NDVI and AVHRR GloPEM NPP data sets, this paper analyzes the response of vegetation dynamics to climate change in the southwestern karst region of China since the early 1980s by extracting each pixel's information. The results show that: (1) since the early 1980s, both vegetation cover density and net primary production have the ascending tendencies. However, interannual variation rates of vegetation indexes have apparent spatial differentiations; (2) correlation coefficients between the interannual variations of vegetation indexes and the interannual variations of climate factors also have apparent spatial differentiations; (3) various vegetation types have different responses to climate change, and the annual mean temperature variations have more significant impact on vegetation dynamics than the annual precipitation variations;and (4) the distribution laws of correlation coefficients between the interannual variations of vegetation indexes and the interannual variations of climate factors under different climate conditions are apparent. The study of the response of vegetation dynamics to climate change in the southwestern karst region of China will enrich our knowledge of the natural courses which impact the stability of karst ecosystems and provide scientific basis for the management of karst ecosystems.
    References | Related Articles | Metrics
    Simulation on the responses of the first four dominant species' productivity to climate warming in Inner Mongolia Leymus chinensis grassland, China
    LIU Qin-pu, LIN Zhen-shan, ZHOU Qin
    2007, 26 (5):  866-876.  doi: 10.11821/yj2007050002
    Abstract ( )   PDF (715KB) ( )   Save
    Global warming affects productivities of plants, and then, the structure and evolution of community. Located in the Xilin River basin in eastern part of Inner Mongolia Highland in North China, the typical primary Leymus chinensis grassland impacted by the global warming has shown depletion to some extent. In order to probe the relationship between global warming and botanic community changes, based on the multi-species competition models given by Tilman and others, this paper puts forward a dynamical model, which is focused on multi-species competition under the condition of disturbances caused by global warming, to simulate evolution of first four dominant species in Leymus chinensis grassland in Inner Mongolia Highland for several score years, which are Leymus chinensis,Stipa grandi,Artemisia commutate and Achnatberum sibiricum. The model considers the proportion of the aboveground net primary productivities (ANPP) of the four species as variables in place of the proportion of sites occupied by species in Tilman's model. The simulated results show: (1) The order of dominant species from the strongest one to the weaker ones would not change if the rate of temperature rise is less than 0.06℃ a-1 in Inner Mongolia Leymus chinensis grassland, China, during the given period of 60 years; otherwise, the original odd dominant species of the first one and the third one will retreat to the second one and the fourth one, and the original even dominant species, the second one and the fourth one, will evolve to become the first one and the third one. The new order is Stipa grandi,Leymus chinensis,Achnatberum sibiricum and Artemisia commutate. (2) The time of rank exchange for the former two dominant species precedes the latter ones. (3) If the rate of temperature rising is more than 0.17℃ · a-1, the new order will be Stipa grand, Achnatberum sibiricum, Leymus chinensis and Artemisia commutate.The simulated results of the order of the first four dominant species' aboveground net productivity are approximately in accordance with field investigation data under the condition of annual temperature arising by 0.086 during 1980-1994 in this area, although there is disagreement with time scale. Results of this research would provide useful enlightenment for predicting Leymus chinensis grassland evolution and helping people to manage it.
    References | Related Articles | Metrics
    Spatial-temporal characteristics of urban heat island effect change of Nanjing city and its relation with land use change
    YANG Ying-bao, SU Wei-zhong, JIANG Nan, ZHEN Feng
    2007, 26 (5):  877-887.  doi: 10.11821/yj2007050003
    Abstract ( )   PDF (799KB) ( )   Save
    How to analyze the change of urban heat island effect (UHIE) and its quantificational relations with land use is one of the difficult problems in the study of the formation mechanisms of its driving forces. This paper analyzes spatial-temporal characteristics of UHIE intensity and scope change of Nanjing city and its relations with land use change using remote sensing and meteorological data. The results indicate that both scope and intensity of UHIE have been increasing since 1985.Viewing from the change of intensity, the changing tendency of annual mean temperature has been going up but the changing tendency of Nanjing city is different from its suburban county of Liuhe, being 0.16℃ during 1986~1990, 0.18℃ during 1991~1995 and 0.262℃ during 1996~2000. From the change of scope, the scope of four-level UHIE in Nanjing built-up area has added 107.88 km2 since 1985. There were two core districts of UHIE in 1985, the biggest one was distributed in Xinjiekou, Fuzimiao and places south of it, the other was in the vicinity of railway station and bus station in Nanjing city. There were three intense UHIE centers in 2000, two of which were in the same positions of the major two in 1985, but their scope increased compared with the former ones.The other one was in the industrial district of Dachang and Pukou. The index of UHIE is used to probe into the spatial difference of UHIE evolution during 1985~2000, the six districts are in the order of Dachang>Yuhua>Shixia>Qixia>Pukou>Jiangning. The major characteristic of land use in Nanjing city is the conversion of natural landscape such as cultivated land, greenbelt and water to man-made landscape. The change of vegetation cover, soil moisture and artificial heat because of land use change is the main reasons of the effect of land use change on urban heat island. According to NDVI, TVDI, artificial heat and LST of every kind of land use, the temperature effect index is provided to evaluate the effect of land use change on urban heat island. The results indicate that land use change in Nanjing city leads to more extensive and intensive urban heat island. The region where urban construction land expands most quickly is also where the urban heat island increases most quickly and the expansion of urban construction land doesn't accord with the increase of urban heat island in space.
    References | Related Articles | Metrics
    Culture and Tourism
    Comparative research on four typical surface roughness length calculation methods
    ZHOU Yan-lian, SUN Xiao-min, ZHU Zhi-lin, WEN Xue-fa, TIAN Jing, ZHANG Ren-hua
    2007, 26 (5):  887-896.  doi: 10.11821/yj2007050004
    Abstract ( )   PDF (843KB) ( )   Save
    There are four typical surface roughness length calculation methods, which are iterative method by least-square fit, Newton iterative method, Temperature Variance Method (TVM method) and a method proposed by Martano. The former two methods need wind speed and temperature profiles in several levels, while the latter two methods use three-dimensional sonic anemometer data in a single level. In this paper, the surface roughness length in various atmospheric stratifications over forest underlying in Changbai Mountains Experimental Station is calculated by the four methods respectively, with wind speed and temperature profiles and three-dimensional sonic anemometer data in 2003. Discrepancy among the four methods and uncertainty of each method are analyzed. The results indicate that, except Martano method, there is minor difference between surface roughness lengths calculated by the other three methods, while roughness length calculated by Martano method is obviously much smaller. By uncertainty analysis of Martano method, it is found out that smaller roughness length calculated by Martano method is probably related to data amount, and calculation results change obviously with data amount. Otherwise, by making uncertainty analysis for the other three methods, it is found out that as for iterative method by least-square fit and Newton iterative method, calculation roughness length is influenced by friction velocity u*, and if u* changes 1% between two neighborhood measurement heights, the calculated roughness length would change by 8.3%. As for TVM method, parameter of C1 changes in such a certain range from 0.9 to 1.05 that the calculated roughness length changes by about 29.9%. By calculating surface roughness length in various atmospheric stratifications with four methods, it is verified that surface roughness length changes with atmospheric stratifications. Surface roughness length in unstable stratification is the smallest, the one in stable stratification is the highest, and in the neutral stratification is medium. Also in this paper specific values in various stratifications are calculated, The results are 2.642, 2.103 and 1.616m for stable, neutral and unstable stratification roughness length, respectively.
    References | Related Articles | Metrics
    Earth Surface Processes
    Spatial factor analysis of karst rocky desertification landscape patterns in Wangjiazhai catchment, Guizhou
    ZHOU Meng-wei, WANG Shi-jie, LI Yang-bing
    2007, 26 (5):  897-906.  doi: 10.11821/yj2007050005
    Abstract ( )   PDF (1000KB) ( )   Save
    The impact of spatial factors on karst rocky desertification landscape was studied in Wangjiazhai catchment.Based on the image of SPOT5 in 2005, with the support of the geographic information system (GIS) and remote sensing (RS) software, karst rocky desertification landscape patterns in the studied area was classified as: no, latent, slight, moderate, strong, and extremely strong karst rocky desertification types. Meanwhile, four spatial factors (slope, slope aspect, elevation and distance to the village) were derived from the digital elevation model. Quasi-quantitative analysis was made on the relationships between the above four factors with karst rocky desertification landscape distribution index (RLDI) and karst rocky desertification comprehensive index (RCI), respectively. Results indicate that: (1)The distribution of various rocky desertification landscapes along the spatial gradient is different. For example, the latent and slight rocky desertification is affected by slope aspect more greatly than that on other spatial factors; while the moderate, strong and extremely strong rocky desertification is highly correlated with the slope gradient. (2)The four spatial factors affect rocky desertification in different ways. For example, 27° is a critical angle for rocky desertification intensity which becomes severer firstly, and then becomes slighter around the turning point. As to the effects of slope aspect, due to the aspect of terrane and exogenic forces including solar radiation and precipitation, the severest rocky desertification occurs in regions of south or southeast slope aspect; and less for north, northeast and east cases, while it is slight in other cases. Moreover, with the increase of elevation, the intensity of rocky desertification is in a deteriorative trend. The regulation of rocky desertification along the distance to the village reveals the mode of human activities on rocky desertification process. (3) The fittings between RCI values and four factors, using the cubic curve estimation method, are obviously different in the descending order: slope>slope aspects>elevation>the distance to the village. The order, in a sense, shows the intensities of those spatial factors on RCI values. Though influences of each spatial factor on RCI could be evaluated by using single-factor correlation analysis, it also should notice that those factors affected RCI mutually.
    References | Related Articles | Metrics
    Analysis of geographic environmental factors on forest landscape dynamics of Yiluo River basin
    DING Sheng-yan, LIANG Guo-fu
    2007, 26 (5):  906-915.  doi: 10.11821/yj2007050006
    Abstract ( )   PDF (788KB) ( )   Save
    Great attention has been paid to the forest landscape change, and the robust modeling of these processes is important for policy as well as academic concerns. The science of forest landscape change analysis is advancing rapidly, with the development of increasingly sophisticated, reliable and accessible tools and techniques. Perhaps the most effort has been devoted to the modeling of deforestation processes including agricultural expansion. This paper concerns a relatively small area of Yiluo River Basin where considerable national and international attention has been paid to slow down the expansion of land for non-forests into the remaining natural forests. In the present study, we reconstructed the former forest landscape structure and elucidated the landscape change from 1983 to 1999. Two sets of maps were used for analyses: forest resources distribution maps of 1983 and 1999. The result showed that there was an increase in the area of the forest landscape from 960.34 km2 in 1983 to 1175 km2 in 1999. Then the approach adopted here is to examine the degree to which forest landscape conversion can be attributed to a set of factors that have been identified as significant at broader scales, namely topography, distribution of the village clusters (centroids), distance from villages (centroids) and forest edge(1983). By using "spatial analysis" in Arc/gis 8.3, the correlation on forest landscape change and driving factors were constructed. The study finds that forest landscape conversion in the concerned area is largely explained by elevation, slope, and village proximity.
    References | Related Articles | Metrics
    Influencing factors of the shrinkage of the braided reach of the lower Yellow River
    YANG Ji-shan, XU Jiong-xin, WANG Zhao-yin, LIAO Jian-hua
    2007, 26 (5):  915-921.  doi: 10.11821/yj2007050007
    Abstract ( )   PDF (585KB) ( )   Save
    The Yellow River has a vast expanse of drainage basin,but most of which is in arid and semi-arid areas.The influencing factors, such as increasing water demand, flow regulations by reservoirs, water diversion, and climate change impose intense effect on the channel. Based on field data in 1960-1997, the relations of several influencing factors with the wet area at full-bank stage of the wandering reach in the lower Yellow River are discussed, and linear multiple regression functions have been found. The bankfull cross-section area of the lower Yellow River experienced four alternating periods with expansion and shrinkage from 1960 to 1997, i. e.1960-1964 expansion, 1965-1973 shrinkage, 1974-1985 expansion and 1986-1997 shrinkage. The variation was caused by many factors.Among them annual runoff was most important and annual sediment load was minor important. The peak discharge in flood season and annual average sediment concentration have also influence. Moreover, water diversion is an important factor affecting the bankfull wet area.Flow regulation by the reservoirs upstream of Lanzhou station exerted a remarkable influence on bankfull wet area. Different operation modes of the Sanmenxia reservoir had a direct effect on the channel of the lower Yellow River, but the influence became limited after 1973 when the reservoir began the operation mode of "storing clear water and releasing flood".
    References | Related Articles | Metrics
    Environment and Ecology
    Emissions of heavy metals from road traffic and effect of emitted lead on land contamination in China: A primary study
    GUO Guang-hui, CHEN Tong-bin, SONG Bo, YANG Jun, HUANG Ze-chun, LEI Mei, CHEN Yu-cheng
    2007, 26 (5):  922-930.  doi: 10.11821/yj2007050008
    Abstract ( )   PDF (1029KB) ( )   Save
    The rapid development of motor traffic in China increases the heavy metal concentrations of the dust, and might contaminate the soils along the roads. In order to quantify the effects of motor traffic on the heavy metal concentrations of roadside soils, the traffic emissions of Pb, Cu, Zn and Cd in individual provinces of China, and the pollution index of Pb in roadside soils, as well as the contaminated areas caused by traffic were calculated by the models induced from the reviews of researches at home and abroad. Results showed that the emissions of Pb, Zn, Cu and Cd from traffic in developed eastern provinces were higher than those in the western provinces. During the years of 1990 to 1996, Pb inputs of the roadside soils in Beijing City ranged from 2.48 to 3.17 mg · kg-1 · a-1, and Pb accumulation was 11.4 mg · kg-1 along the roads because of the use of lead in gasoline. After inverting to lead free gasoline, Pb inputs of the roadside soils in Beijing City decreased to 0.26 ~ 0.29 mg · kg-1 · a-1 from 1997 to 2003, and Pb accumulation was only 1.30mg·kg-1. Lead concentrations in roadside soils decreased rapidly with the increase of distance from road. The land with the distance up to 10 m from road was heavily contaminated by Pb emitted from traffic, and that moderately contaminated between 10 and 65 m. According to the models, the areas of contaminated lands by Pb from motor traffic in Beijing and China were 289 km2 and 3.63×104 km2 in total, respectively. The results revealed that the traffic emission is one of the important reasons of heavy metal contamination of soils in China. This study provides both the models for the relationship between motor traffic and heavy metal concentrations in roadside soils, and the practical guiding for the prevention of heavy metal contamination by motor traffic.
    References | Related Articles | Metrics
    Study on the evolvement of the relationship between industrial wastewater discharge and economic growth in Jiangsu Province
    ZHOU Jing, YANG Gui-shan
    2007, 26 (5):  931-939.  doi: 10.11821/yj2007050009
    Abstract ( )   PDF (545KB) ( )   Save
    Industrial wastewater discharge is the most important source of water pollution in China, and the water environment in humid regions has burdened heavily in the process of industrialization. This paper analyzed the discharge characteristics of industrial wastewater from 1980 to 2004 in Jiangsu Province, which is located in the eastern developed area of China, the relationship between the discharge amount and the economic growth, and the factors influencing discharge change. The result showed that because of the steady development of economic growth, the amount of industrial wastewater has increased slowly with some fluctuations since 1980, while the discharge intensity decreased. Compared to the increase rate of GDP in Jiangsu during the same period, the growth rate of wastewater was much slower. The source of industrial wastewater came mainly from both manufacturing sector and energy producing sector. Nanjing city, three cities in southern Jiangsu, and nine cities in cemtral-northery Jiangsu possessed about 1/3 of the total annual wastewater discharge of the province each.The relationship between industrial wastewater and economic growth was also simulated adopting the Environmental Kuznets Curve model. The studies argued the relationship between industrial wastewater discharge and GDP per capita was an inverted U-shaped+U-shaped model in 1980-1996, while inverted U-shaped model in 1997-2004. Simulation reveals that the discharge amount tends to climb up in a short period and then declines with the economic development. Applying decomposition analysis, factors influencing industrial wastewater discharge in the periods of 1997-2000 and 2001-2004 were decomposed into generalized technical effect (GTE), scale effect and structure effect. The result showed that GTE and scale effect were the most important factors determining discharge change, while GTE had crucial function on pollution control.Stimulation of the enterprises-induced pollution suggests that the environmental policy should place emphasis on enhancing the contribution of GTE in Jiangsu province in the future.
    References | Related Articles | Metrics
    The research of ecological footprint and ecological carrying capacity prediction model based on space
    CHANG Bin, XIONG Li-ya, HOU Xi-yong, DING Yi
    2007, 26 (5):  940-948.  doi: 10.11821/yj2007050010
    Abstract ( )   PDF (665KB) ( )   Save
    In recent years the ecological footprint (EF), originally developed by Wackernagel and Rees in the mid-1990s(Wackernagel M and Rees W,1996,1997), has gained much attention in ecological economics. This method tracks natural resources consumption of a nation or a region and translates them into biologically productive land area, which is required to produce the resources and to assimilate the wastes.EF calculation should be based on different scales (globe, nation, region, city or individual) of consumption. And then we can compare the EF and the ecological capacity (EC) of the same scale to determine the ecological status of this scale. Most of the researchers used statistical data and models to calculate EF and EC; however, the calculation is static. Moreover, the theory and methodology of EF and EC prediction have not been developed in literature so far. This paper is one of the few quantitative studies of EF and EC predictions. In the paper, the concept, theory and method of ecological footprint are introduced which can measure the goal of sustainability. On the basis of it, the study brings forward the method of EF and EC prediction.In terms of EF prediction, the method of combining consumption model with population model is adopted while for EC prediction the method of combining geographical cellular automata with GIS is used. The above models and methods are employed to calculate EF and EC in 1995 and 2000 and predict them in 2005 in Hexi Corridor. The result shows that EF is continually increasing, and EC ascended in the anterior five years and will descend in the posterior five years. This calculation and prediction model method is characterized by accuracy, speediness and high operability but the prediction method is of limitation to a certain degree.
    References | Related Articles | Metrics
    Hydrology and Water Resources
    Energy consumption and the spatial distribution characteristics of shallow groundwater mining in the south Haihe River plain
    ZHANG Shi-feng, XU Li-sheng
    2007, 26 (5):  949-957.  doi: 10.11821/yj2007050011
    Abstract ( )   PDF (550KB) ( )   Save
    This article inferred the formula of accounting energy consumption in mining shallow groundwater, based on the supposition that the energy consumption of groundwater mining is equivalent in the mining well and in its radius of affected area. According to the characteristics of evolution of shallow groundwater seepage field in the south Haihe River plain in the three periods of time, namely, the 1960s, the 1980s and initial period of the 21st century, as wall as integrating the GIS technique,we account the energy consumption and their differences in groundwater mining of the three different typical years (1964, 1984 and 2001) of the three periods. The results indicated that, when shallow groundwater table drops deep for 1m in the study area in 1964, 1984 and 2001,the energy consumption of groundwater mining is respectively 0.16×108 kw · h, 0.65×108 kw · h and 1.2×108kw · h; when shallow groundwater table drops deep for one unit, in comparison with the three different periods of 1964-1984, 1984-2001 and 1964-2001, the energy consumption difference of shallow groundwater mining is respectively 0.49×108kw · h, 0.55×108 kw · h and 1.04×108 kw · h. After analyzing the spatial distribution map of energy consumption of shallow groundwater mining in different periods of time in the south Haihe River plain, it is found out that, since the 1960s, the energy consumption of shallow groundwater mining has increased substantially, from average 269kwh/km2 to average 1781kwh/km2, due to groundwater overdraft.The computation of the energy consumptions and their difference of shallow groundwater mining both assume the increasing tendency from the alluvial and coast plain region to the Taihang piedmont plain region, the maximum energy consumption of groundwater mining is from 68 kwh/km2 to 8908 kwh/km2, but the energy consumption difference of shallow groundwater mining increases from 4760 kwh/km2 to 8568 kwh/km2.The research results could be used to provide the reference for the social and economic benefits appraisal of the shallow groundwater table rising after implementation of the South to North Water Transfer Project in the study area, and provide service for the research of the local construction of an "abstemious society".
    References | Related Articles | Metrics
    The analysis of hydrological characteristics and processes of ecosystem in Lake Nansi during the past 50 years
    ZHANG Zu-lu, XIN Liang-jie, LIANG Chun-ling
    2007, 26 (5):  957-966.  doi: 10.11821/yj2007050012
    Abstract ( )   PDF (734KB) ( )   Save
    Wetlands, named as the kidney of nature, are transitional areas between aquatic and terrestrial ecosystems, and often have the unique characteristics of both. Wetlands perform functions such as providing habitat for birds, animals and plants, and cleaning water of nutrients and pollutants, and these functions make wetlands important and valuable to humans. But in recent years, due to both disturbances of the nature and human, worldwide wetlands have shown a degraded trend. Based on the data from hydrographic monitoring, field survey and analysis of experiments, this paper analyzes the hydrological characteristics and ecological degradation pattern of Lake Nansi in the last 50 years. As one of the biggest lake wetlands in North China, Lake Nansi wetland plays an important role in reserving the regional biodiversity and adjusting climate. The water inflow into Lake Nansi is obviously decreasing with a rate of 5.5×108m3/10a. Water reduction, mud and hydrophyte deposit make Lake Nansi shrink and block up. The lake is dying out. The water environment of Lake Nansi polluted by the waste water of Jining and coal mines is so serious that the security of the lake's ecosystem has been severely affected. As a result, human couses much more damages to the environment than the nature. The deterioration of water environment of Nansi Lake has badly endangered the health of the ecosystem and restricted the sustainable development of society and economy. On the basis of the above-mentioned analysis, the paper puts forwards some brief suggestions on wetland conservation.
    References | Related Articles | Metrics
    Simulation and analysis of water system in the pollution-induced water shortage region based on SD
    GAO Cheng-kang, BAO Cun-kuan, JIANG Da-he, DONG Jia-hua, HUO Li
    2007, 26 (5):  967-974.  doi: 10.11821/yj2007050013
    Abstract ( )   PDF (978KB) ( )   Save
    At present, the studies of water system mainly focus on water problems in arid region, while the pollution-induced water shortage problems are almost neglected.The relevant methods are mostly half-quantitative, and the results are almost macro-scope related suggestions.The pollution-induced water shortage problems takes on some characteristics, e.g. man-made effect, all-around in function and randomicity in process.The paper considers comprehensively the pollution-induced water shortage problem in southern China where water resources are abundant. And based on System Dynamic (short for,SD) water system under different policies is simulated.Taking Yangpu district in Shanghai as a case, according to its characteristics the model which includes five subsystems and six control parameters is built.The model runs and produces three kinds of desired schemes by adjusting control parameters.Based on the results the paper identifies the main impact factors of water system: water price, ratio of sewage treatment, consciousness of water saving, and technical reform. Combined with the simulation results, some reasonable policies are put forward in order to realize the balance between supply and demand on water resource, and to realize harmonious development in the region.The corresponding measures mainly refer to a rise in water price, consciousness of water saving and the ratio of sewage treatment, and reform technical in production, which can solve effectively the pollution-induced water shortage problem.Some policies depend on regulated and control reference values(corresponding years: 1990/1995/2000/2005/2010/2015/2020): TPW (water price)= 1.3/2.7/2.9/3.5/4.7/5.2/6.8; TRWW (ratio of sewage treatment)=0.73/0.79/0.84/0.85/0.93/0.96/0.97; consciousness of water saving, INDEX1=2.5(after the year 2005),INDEX2=1.021(before 2005); at TRT (technical reform.)=1/1.1/1.28/1.35/1.5/1.65/1.66.It is predicted that water system balance between supply and demand will come true in 2010 because then the total demand of water is about 14.0×109(t) and the capacity of water supply arrives at approximately 13.9×109(t).But the model can not reflect the pollution-induced water shortage phenomena due to pollution accidents; and can not provide quantitative relationship between some control-parameters, so both problems are the topics of concern in seeking for the solutions to the pollution-induced water shortage problems.
    References | Related Articles | Metrics
    The application of groundwater model, MODFLOW, and GIS technology in the dynamic evaluation of groundwater resource in North China Plain
    WANG Shi-qin, SHAO Jing-li| SONG Xian-fang|ZHANG Yong-bo, ZHOU Xiao-yuan| HUO Zhi-bin
    2007, 26 (5):  975-983.  doi: 10.11821/yj2007050014
    Abstract ( )   PDF (606KB) ( )   Save
    Nowadays the water resources shortage and pollution of North China Plain is very prominent. Especially groundwater is the main water source and supply. To build a groundwater model and integrate it into the geographic information system (GIS) is an important method to realize the sustainable use and management of water resource of North China Plain. As a result of the clear construction and independent modules of groundwater model program MODFLOW,which is based on the finite difference method, the original program packages could be modified and the new package could also be added into it according to the needs of integration. In this paper the integration relationship between groundwater model and GIS was established after analyzing the input and output data format of groundwater MODFLOW and the geological and hydrogeological data format of North China Plain where most data were mainly composed of MAPGIS format. And it was applied to the groundwater evaluation of North China Plain. According to the hydrogeological condition of North China Plain, the three dimensional transient groundwater flow model was constructed. Parameters were validated using flow net of observation pores in December 2003. and the dynamic water level data between January 2002. and December 2003. The parameters include conductivity coefficient, specific yield and storativity of aquifers. During the process of constructing the groundwater model, a water budget was analyzed, which resulted in a negative budget in the North China Plain. The simulation period was from January 1,2002 to November 12,2003. During this period the total recharge of the groundwater system was 493.74 108m3,and the total discharge was 565.30×108m3,and the budget deficit was -71.56×108m3. The system with groundwater of North China Plain can dynamically evaluate the groundwater resources under the net circumstance by using the source and sink data in database which can provide reference valuable for the use and management of water resource.
    References | Related Articles | Metrics
    Economy and Regional Development
    Locational accessibility and location of foreign enterprises in Beijing
    ZHANG Hua, HE Can-fei
    2007, 26 (5):  984-994.  doi: 10.11821/yj2007050015
    Abstract ( )   PDF (630KB) ( )   Save
    To understand urban restructuring process, the intra-urban location behavior of foreign enterprises should be fully investigated.Due to the lack of disaggregated data, few studies have focused on the intra-urban location of foreign enterprises. Compared with their domestic counterparts, foreign enterprises are rational decision-makers and have more flexibility in choosing their locations. Governed by market forces, foreign enterprises are not randomly distributed within a city and their location patterns are detectable. Based on data from the second census of basic units, this study geo-references foreign enterprises in Beijing by their postal codes and captures site attributes through cross-referencing enterprises distribution with other spatial coverage such as railway stations, airports, land uses, and designated development zones.The Poisson regression model is applied since the dependent variables are the number of foreign enterprises within a particular postal code. Statistical results show that foreign enterprises tend to agglomerate in the central city and are located close to the important transport infrastructure such as railway stations, airports and highways. Statistical results suggest that locational accessibility plays a crucial role in attracting foreign enterprises within Beijing. Proximity to universities, embassies and industrial parks are also important locational determinants for foreign enterprises. Significant differences exist in the locational behaviors of different types of foreign enterprises.
    References | Related Articles | Metrics
    Relevancy analysis of the coupling between population structure and regional economy in Inner Mongolia
    BI Qi-ge, BAO Yin, LI Bai-sui
    2007, 26 (5):  995-1004.  doi: 10.11821/yj2007050016
    Abstract ( )   PDF (852KB) ( )   Save
    Based on previous censuses of Inner Mongolia, spot check of population in several years, Inner Mongolia Autonomous Region statistical almanac in several years and related material, the dissertation established an evaluation index to the coupling between population structure and regional economy according to the current development and problems of the region. Using methods of qualitative and quantitative analysis, and grey correlative analysis, the dissertation built a correlation model and a coupling model of the interaction between population structure and regional economy of Inner Mongolia.It analyzed the coupling between population structure and regional economy of Inner Mongolia, the static space distribution of the coupling of counties in Inner Mongolia in 2000, the dynamic contrast of distribution in 1990 and 2000 and the evolving rule of the coupling from 1993 to 2004 in Inner Mongolia. The results show, that the coupling mechanism between population structure and components of regional economy is sophisticated, population structure is closely connected with the development of regional economy in Inner Mongolia; but the coupling distribution degree between population structure and regional economy of Inner Mongolia presents an inverse law to population scale.Inner Mongolia can be divided into four types: harmony, amelioration, conflict and low-level coupling. In general, amelioration predominates, followed by low-level coupling, compared 2000 with 1990, the coupling degree increases dynamically; and the sequential change of the coupling degree between population structure and regional economy of Inner Mongolia present different phases and undulations.
    References | Related Articles | Metrics
    Free-scale structure anlaysis of town road networks in southern Jiangsu Province
    SU Wei-zhong, YANG Gui-shan, ZHEN Feng
    2007, 26 (5):  1005-1012.  doi: 10.11821/yj2007050017
    Abstract ( )   PDF (686KB) ( )   Save
    Understood from the viewpoint of Graph Theory, free-scale structure essentially is the exponential function of vertex degree, D, in network graphy. The paper proposes rank vertex degree (Dr) and population size vertex degree (Dp) on the basis of the numeral vertex degree (D) of regional town road networks. Firstly, town road networks are discribed based on mathematics method, which aims to reveal the heterogeneity structure of three kinds of vertex degrees from the math background. The results show that the characteristic of free-scale structure is relative, and changes with the analysis objects and their attribute and scale; vertex degree D does not exhibit free-scale property, while Dr and Dp form free-scale structure; and the exponential function of town poulation sizes of a region corresponds with Rank-Size Rule of urban system. Then, town road networks are analysized on relational analysis of SPSS and spatial analysis of GIS, which aims to find the relationship between town vertex degrees D, Dr and Dp. The results show that the correlation coefficient between Dp and D is 0.569 while the correlationship and spatial contacts on town road networks graphy between Dp and Dr are all very evident. The numbers of roads linked by each town are limited and cannot be changed into free-scale structure because of two-dimensional spatial distribution on earth surface and costly construction expense of these roads. The Poisson distribution of D is affected not only by population size of towns but also town location and others factors. High ranked roads are contact bridges of production and communication among cities whose spatial pattern influences these roads assign and pattern. Accordingly these high ranked roads and "spill-over effect" of urban change road linkage priority mechanism of towns, which results in Dr upgrade of some towns in some specific area. Town population sizes increase with their vertex degree Dr upgrade. Dr and Dp of town road network shows exponential function distributions structure in the end. The above inherently mutual mechanism between town population size and its road linkage rank spatially shows the "Core-Belt" model of town development in the rigion, where the "Core" corresponds to the area around cities, and the "Belt" corresponds to the area around high ranked roads. The open town clusters model benefits both economic development and eco-environmental convocation.Finally the paper suggests that the area of Suzhou city, Wuxi city, Changzhou council area and Wujin city need controlling towns high-dense pattern model, where town centralization and consolidation policies should be conducted, and the development and pattern of high ranked roads need proper control and scientific planning; the area of Nanjing city, Zhenjiang city, Jintan city and Liyang city need to strengthen developing towns around high ranked roads, but avoid the overspread pattern of towns.
    References | Related Articles | Metrics
    The analysis on development dominance ratio of agricultural resources in Gansu Province
    ZHENG Hai-xia, FENG Zhi-ming
    2007, 26 (5):  1013-1020.  doi: 10.11821/yj2007050018
    Abstract ( )   PDF (1077KB) ( )   Save
    High-efficient utilization of agricultural resources is a key factor for food security, and the order list of agricultural resource utilization can provide effective reference for further exploitation of agricultural resources. In this article, the author puts forward the concept and estimates model of development dominance ratio of agricultural resources on the basis of agricultural produce potential and agricultural resources utilization efficiency. Taking Gansu province as a case, the list of development dominance ratio of agricultural resource is evaluated and analyzed. The results of the study show that: the model of development dominance ratio of agricultural resource can simulate further exploitation potential and regional difference of agricultural resources in Gansu province. Farmland development dominance ratio can reflect comprehensive development dominance ratio. In the rain-fed agricultural zone, such as Longnan, Longdong and Longzhong districts, the development dominance ratio of agricultural resources is about 4 to 5 levels. The condition is the same in the plateau region of Gannan Prefecture, due to the high exploitation potential of abundant light resources. Because irrigation agriculture promotes farmland productivity, in Hexi Oasis irrigation agricultural zone, the development dominance ratio of agricultural resources is lower, being 1 to 2 levels. However, because the agro-ecosystem is degenerated, the development dominance ratio of agricultural resources in Minqin and Jinchang districts is lower than other irrigation zone, being about 3 levels.
    References | Related Articles | Metrics
    Urban and Rural Studies
    Modeling the urbanization process of China using the methods based on auto-correlation and spectral analysis
    CHEN Yan-guang
    2007, 26 (5):  1021-1032.  doi: 10.11821/yj2007050019
    Abstract ( )   PDF (696KB) ( )   Save
    China's urbanization cannot be modeled by the logistic equation, which is followed by the USA's urbanization process. In order to reveal the features and property of China's urbanization, the auto-correlation and spectral analysis are employed to make a multifold study on time series of urbanization from 1949 to 2000. (1) An autocorrelation analysis is implemented, and partial autocorrelation function (PACF) has a first order cutoff. This implies that the urbanization process of China possesses a locality: a change in the i-th year only affects that in the (#em/em#+1)th year directly, but cannot affect the changes in and after the (#em/em#+2)th year. However, the auto-correlation function (ACF) suggests that a change perhaps influence a change ten years later indirectly. (2) An autoregressive analysis is made and an autoregressive moving-average (ARMA) model is built such as Lt=μ+Lt-1+lim q→∞ ∑ q j=0 φjεt-j=0.510+Lt-1+lim q→∞ ∑ q j=0 0.439jεt-j where Lt is the #em/em#-th year's urbanization level, ε is an innovation or "random shock" (white noise), φ is a parameter, and q the order of moving average. (3) A spectral analysis is made based on the residuals of the logistic model, that is, the logistic trend of urbanization level is removed from the time series, and the result shows that there exists a periodic change behind the trend change. The wavelength (cycle length) is about 30 years. The Hurst exponent of the urbanization data is estimated to interpret the periodic behavior. The value of the Hurst exponent, H=0.37, suggests anti-persistence in the urbanization process of China. Based on the above analyses, the process of urbanization is divided into three parts: random process, periodic process, and trend process. Among the three different components of change in urbanization, trend is a basic process, cycle is an accessorial process, and random change is a complex process. The future of China's urbanization is hard to be predicted using the common methods because of auto-correlation and random disturbance, so new approaches should be found to conduct a convincing prediction.
    References | Related Articles | Metrics
    Research on private cars&rsquo|influence on residential space based on residents&rsquo|travel behavior: Taking Dalian as an example
    LI Xue-ming, DU Jing-yu
    2007, 26 (5):  1033-1042.  doi: 10.11821/yj2007050020
    Abstract ( )   PDF (746KB) ( )   Save
    The development of transportation system is a major inducing means for urban growth. The increase of the private cars has changed the traffic structure. It has strengthened the space accessibility, and improved the transport capacity.Long distance is never an obstacle, which changes people’s house purchasing mind and gradually induces people, commercial centers and related industries to move to the edge of a city and influences the pattern and scale of the residential space. Finally it makes the residential area become larger and broader.Research on private cars’ influence on residential space based on residents’ travel behavior has expanded the research field in the traffic and land-use relationship from the view of private transport means.This research has important meanings in guiding urban planning which integrates urban residential area with transportation. Taking Dalian as an example, this paper researches the private cars’ impact on the residential space based on the residents’ travel behavior between jobs and housing. Through survey of private cars’ quantity, the residents’ travel behavior and the partiality of housing location, the information of residents’ social attributes, behavioral space and psychology partiality is acquired. and then simulation and analysis are done using the GIS technology.The result shows, residents’ car-purchasing behaviors have certain relevance with jobs-housing spatial distribution situation. Because of the unharmoniousness between jobs and housing in the expansion area, travel inconvenience is the major problem, the long commuting distance and time is the only factor which reduces the residents’ evaluation to the urban expansion area. This factor can only be improved through the improvement of the transportation means and traffic routes.The increase of the private cars has strengthened the convenience and swiftness. Five kilometers away from the city centre, the increase of the number of the private cars with the further expansion of the residential space make the whole scale of the city expand through the effect of circular and accumulation. Meanwhile, the statistic software is used to set up geographical model and analyze private cars’ impact on the expansion of residential space. The calculation indicates that of the various kinds of influencing factors, private cars’ contribution rate reaches 2.14% in average during 1990 to 2004.
    References | Related Articles | Metrics
    Spatial distribution and trends of the aging of population in Guangzhou
    LIN Lin, MA Fei
    2007, 26 (5):  1043-1054.  doi: 10.11821/yj2007050021
    Abstract ( )   PDF (1886KB) ( )   Save
    The appearance of the aging phenomenon is an inevitable result in the development of society. The aging seriously influences urban economy, society and culture, especially spatial configuration of a city. Under such a situation, the analyses and studies on the aging of population are very prevalent.This paper studies the spatial distribution and trend with Metric-geography, GIS and sociology, and it also tries to explain them from dynamic aspect and static aspect. First of all, consulting the universal standard which weighs the degrees in aging of population, this paper selects six indexes about aging of population, and then calculates and analyses the spatial characteristics of aging phenomenon in Guangzhou through fuzzy classifying analytical method. After analyzing the spatial structure of aging in Guangzhou, the circinal characteristics of the aging of population from push modes, and aging degrees are obtained.Through fuzzy clustering analysis and selecting typical indexes, the paper studies ten city zones and two city towns, then gets the aging spatial structure which has circularity differential characteristic.As a whole, three types of the aging spatial structure can be classified, which are Elder-Late stage,including Yuexiu, Dongshan, Liwan, Haizhu and Fangcun; Elder-Midterm stage, including Baiyun, Panyu, Tianhe and Huangpu; and Elder-Initial stage, including Zengcheng, Conghua and Huadu. Then, with the Geographic Information System Software(Arc GIS) and Geodata Analysis Software(Geo DA), this paper analyzes the reason on the circularity structure of the aging of population, explains the circularity structure with the clustered-disperse effect of the aging, and then analyzes the clustered-disperse trend.Specifically, the central zone has dispersed trend, the interspace zone has clustered trend, and the trend in-between the dispersed and the clustered is the marginal zone. Based on the analysis, three clustered-dispersed types, such as central dispersed zone, marginal clustered zone, and interspace clustered and dispersed zone are identified. The factors, such as policy, economy, society, culture,etc, affect the aging of population in Guangzhou, which are reflected in the natural growth of population and the migration of population. The reason for the difference in spatial distribution is due to the rapid change of the rate of migration between different circularities.
    References | Related Articles | Metrics
    Comparison of influencing factors for residential mobility between different household register types in transitional urban China:A case study of Guangzhou
    LIU Wang-bao, YAN Xiao-pei
    2007, 26 (5):  1055-1066.  doi: 10.11821/yj2007050022
    Abstract ( )   PDF (458KB) ( )   Save
    As a more and more important statistic method in studies of residential mobility, longitudinal analysis could dynamically simulate residential mobility because this analysis could relate residential mobility to not only specific events or triggers in personal or household's life, such as marriage change and the birth of a child, but also the main changes of housing market in a broader social and economic context. Making use of survey data collected in Guangzhou in 2005 and forming personal-year longitudinal data spanning from 1980 to 2005, the longitudinal analysis results show that residential mobility rate manifests a rising trend from 1980 to 2005 with close connection with housing reform process.Non-native population has evidently higher mobility rate than native population because non-native population has higher rate of employment change, leading to big probability of residential mobility. Housing types, marital status change, job change and time variable indicating the housing form process, housing market and distributional environment and household's life cycle respectively all have significant effects on residential mobility of non-native and native population, but the significant extent has big differences. Life-cycle change is more significant in causing residential mobility of native population, but job change which will change the commuting cost is more significant for the non-native population, indicating the essential differences between the non-native and the native population. Residential location has significant impacts on native population's residential mobility with higher probability of residential mobility of those who reside in the suburban area, but has insignificant impacts on residential mobility of the non-native population.
    References | Related Articles | Metrics
Share: