Table of Content

    20 November 2008, Volume 28 Issue 6 Previous Issue    Next Issue
    Industrial Agglomeration of Manufacturing Industries in China——A Comparison of Jiangsu and Anhui provinces
    HE Can-fei, ZHU Sheng-jun
    2008, 28 (6):  715-721.  doi: 10.13249/j.cnki.sgs.2008.06.715
    Abstract ( 201 )   PDF (946KB) ( 37 )   Save
    Geographical agglomeration of manufacturing employment in China is pervasive. The degree of industrial agglomeration of individual industries depends on both industrial-specific and regional-specific factors. One industry may exhibit different locational patterns in different regions. This paper uses plant-level data collected from the second census of basic units in 2001 to compare the geographical agglomeration of manufacturing employments in Anhui and Jiangsu provinces. Overall, manufacturing employments are more geographically agglomerated in Anhui than in Jiangsu. The most agglomerated industries belong to resources-processing capital intensive and technology intensive industries while the most dispersed ones are those requiring localized resources inputs and market-oriented industries. Heavily protected industries by local governments are also fairly geographically dispersed. Some resources-processing industries, capital and technology intensive industries and industries with long traditions differ significantly in the degree of agglomeration in Anhui and Jiangsu. The regional differences of industrial agglomerations are associated with regional inequalities in economic development, infrastructure and urbanization as well as geographical location, resources accessibility and industrial traditions. In the transitional China, differences in institutional environments also lead to interregional disparities in industrial agglomeration.
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    New Pattern of Regional Economic Polarization in the Three Provinces of Northeast China
    LI Xiu-wei, XIU Chun-liang
    2008, 28 (6):  722-728.  doi: 10.13249/j.cnki.sgs.2008.06.722
    Abstract ( 146 )   PDF (1134KB) ( 20 )   Save
    This paper examines the spatial polarization of regional economy in the three provinces of Northeast China. Municipal jurisdiction, city proper and county were respectively used as the basic units of analysis, for each of which the GDP and per capita GDP as collected or calculated. The degrees of inequality and polarization of regional economy for the years of 1990, 1995, 2000 and 2005 were evaluated with Gini Coefficient, Wolfson Index, and TW Index. Spatial autocorrelation analyses were employed to identify the "hot places" of economic development, and explore the patterns of polarization of regional economy, of which city proper and county were basic units.The research reveals that the polarization of regional economy progresses in each of the three units mentioned above in Northeast China since 1990, and the city district economy is the most polarized among them. A spatial trend has been exhibited for economic center of gravity to move southward. The areas with high value in spatial autocorrelation analysis have been turning from scatters to axial and planar distributions. Dalian, Shenyang, Changchun and Harbin, are high "polarizing points", and discontinuous "polarizing axes" are along Harbin-Dalian and Manzhouli-Harbin-Suifenhe railroad. The area with High value covers all the Middle-and-South Liaoning, meanwhile, low value areas extend in North Heilongjiang, East and West Jilin, and West Liaoning, and become more continuous.The polarization results in that in Northeast China, regional economic system tends to become less hierarchical, and the economic growth among prefectural cities, with the Four Cities excluded, tends to become equality. The polarization also brings varying degrees of developments to Middle-and-South Liaoning Economic Region, Harbin-Changchun Region (Harbin, Daqing, Qiqihar, Songyuan, Changchun, and Jilin City), Manzhouli-Harbin- Suifenhe Economic Axial Belt, the major structures of regional economy in Northeast China.
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    Socio-economic Spatial Structure Based on RS and GIS Technology——Case study of Chongqing
    WANG Yang, ZHAO Wan-min
    2008, 28 (6):  729-735.  doi: 10.13249/j.cnki.sgs.2008.06.729
    Abstract ( 149 )   PDF (1293KB) ( 25 )   Save
    Taking RS and some other related spatial information as data sources, this paper analyzed the socio-economic spatial structure of Chongqing with GIS spatial modeling mode. At first, this paper introduced the related background and analyzed the logical pattern for mapping and inversing soco-economic system with GEO-INFO mode, technical outline of this research had been confirmed at the very beginning. With the help of basic spatial model—trend surface, this paper build seven trend surface models for late analyses, those trend surface included: population density trend surface,population activity strength trend surface,city-town spatial density trend surface, ratio of urbanization trend surface, road density trend surface, GDP density trend surface and average GDP density trend surface. The methods to build trend surfaces included: Kriging interpolate model, density mapping and GIS-software’s grid calculator. Helping with this result trend surfaces, this paper used Fuzzy ISODATA ( Fuzzy Iterative Self-Organizing Data Analysis Techniques Algorithm) techniques algorithm synthetically to analyz those data, and subdivided Chongqing into three regional types:Ⅰ, urban-oriented,Ⅱ, transition region, Ⅲ, rural-first industry-oriented region. Contrasted with the economic regions of Chongqing, the clustered result had some different traits compared with the imagination of local government. To get more information of regional economic spatial structure, this paper used some spatial structure measure models which is come from Landscape Ecology, including: type dominance index(TDI), patch density(PD), edge density(ED), type diversity index(TDI) and mean patch fractal dimension(MPFD). Helped with these indicators, this paper analyzed the detail information of cluster result. Through the calculation process, some useful information can be drawn out. For example, with this calculation process, the proportion basic type area can be confirmed: typeⅠis 9.72% , typeⅡis 36.38%, type Ⅲ is 53.90%, but for part of Chongqing—Chongqing metropolitan area(the most prosperous area of Chongqing) ,the preportion 46.61 %, 42.30 % and 11.09 %. Three Gorge areas(the un-developmental area of Chongqing), the data are 3.84%, 28.84%, 67.32%. So with this basic data, we can understand how many the disparities exist between different regions of Chongqing and the places which the disparity stand out can be confirmed. For the indicators calculation result, the highest values separately for TDI, PD, ED, TDI, MPED are 0.3485, 0.0018, 2.7419, 0.9636, 1.0246, data respectively represent western economic corridor of Chongqing, Chongqing metropolitan area and Three Gorge area of Chongqing. Accordingly, the lowest values separately for TDI, PD, ED, TDI, MPED is 0.1350, 0.0006, 1.6179, 0.7501, 1.0178, this data respectively represent Chongqing metropolitan area, Three Gorge area, and west economic corridor of Chongqing. With this basic data, it can be confirmed that there were two regional economic breadlines generated in Chongqing, one is lies between Chongqing metropolitan area and Three Gorge area of Chongqing, the other is situated at the inner part of Chongqing metropolitan area, belong to the transition area between city and rural area.
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    Based on VM-MapInfo Methods About Regional Development Intensity Measurement——Take an Example of Dalian City
    WANG Li, HAN Zeng-lin, LI Bo
    2008, 28 (6):  736-741.  doi: 10.13249/j.cnki.sgs.2008.06.736
    Abstract ( 114 )   PDF (1328KB) ( 168 )   Save
    The development intensity refers to the ratio of the building area to the total area in one region. It is not only a key guideline which needs to be measured in Major Function Oriented Zoning, but also a basic means to control the total area of construction and to optimize the spatial structure. Although the basic ideas and formula of measuring the development intensity are clearer, there are many issues which need to be exploring, such as specific database based on GIS, measuring technical line, conclusion expression and so on. Based on VM-MapInfo, this paper accounts the development intensity of all regions taking an example of Dalia City. By adopting basic ideas, working process and technique methods, it is a useful method that resolves the technical questions to deduct elevation limit construction, kinds of agriculture and other limit construction uses during the regional development intensity reckoning. It has the important guiding sense to survey the region development intensity. By measuring , Dalian current situation construction land, future construction land, surplus construction land are 1333km2, 3237km2, 1904km2, and the corresponding development intensity, the future potential intensity, the surplus development intensity respectively are10.4%, 25.1%, 14.8%. First, the southern areas of Dalian City, especially the construction land of three districts, Ganjingzi District is developed already "excessive". It also has certain area not suitable for urban and industry building. Second, future construction land mainly distributes in the northeast area of Dalian City. It considers building industrial development area and population gathering area in construction concentrate area. Third, future construction land includes three types which are coast abandoned salt field and tidelands, countryside residential area and unutilized ground. The conclusions instruct Dalian's spatial layout in optimizing and guiding the construction of the industrial park, urbanization overall arrangement, the cultivated land and basic farmland protection.
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    Evaluation and Analysis of the Major Urban Human Settlements Based on Embodying Self-Realization Needs in China
    Li Xue-ming, Li Ming
    2008, 28 (6):  742-747.  doi: 10.13249/j.cnki.sgs.2008.06.742
    Abstract ( 149 )   PDF (628KB) ( 54 )   Save
    Urban human settlement is a critical criterion in judging the developmental level of a city. It is safe to say that it is the reflection of urban economic circulation and environmental construction in the sense of geographical space under urbanization. It is an important subject to evaluate the degree of urban human settlement, to analyse the problems in various cities, to make a classification in the angle of self-realization, and to explore its regional similarities, characteristics and reasons that cause the distinction. The self-organization feature maps network model was firstly applied to the evaluation of main urban human settlements in China. Urban human settlement is not only a critical criterion in judging the level of development of a city, but also a possible tool to make a classified judgment on urban human settlements in 35 of main cities from different angles such as economic realization, digital realization, acquisitive realization, residential realization, transporting realization, security realization, virescence realization, recreational realization and natural environmental realization, to distinguish the differences in different cities, so as to provide basis for construction and management of urban human settlements in different cities. Based on the research, the urban human settlements in China is provided with the particularity of obvious regional distinctions: its quality in littoral cities is mostly higher than that in the middle and western regions. It shows that the geographical elements count fundamentally in urban human settlements, and economic capacity is highly connected with it. The top seven cities in the evaluation of urban human settlements all come from the developed eastern littoral, for the prosperity of the cities provides more job opportunities and better surroundings. Meanwhile, the funds allocated to the construction of the infrastructure and the melioration of environmental conditions need the support of prosperous economy. From the view of classified evaluation, the self-realization of people requires more on economic realization, digital realization, residential realization, transporting realization, security realization, virescence realization, and recreational realization. In other words, in urban human settlements, the economic environment, salary, circulation of information, degree of modernization, virescence condition and the comfort of living are the main ingredients when choosing urban human settlements in the process of self-realization. This model based on the SOM neural network is applied to quality evaluation of main urban human settlements in China. The evaluation value indicates the current situation of urban human settlements and relative levels in China.The run results of the model show that the application on quality evaluation of urban human settlements based on the SOM neural network is convenient, precise and feasible which proves to be a valuable evaluation approach.
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    Tourism Spatial Structure of Resources-based Attractions in China
    XIE Zhi-hua, WU Bi-hu
    2008, 28 (6):  748-753.  doi: 10.13249/j.cnki.sgs.2008.06.748
    Abstract ( 250 )   PDF (1111KB) ( 52 )   Save
    With the rapid development in economy, the tourism industry of China is also booming. Though there are more and more man-made attractions such as Themed Amusement Park, traditional attractions with natural beauty and/or historical sites are still within the most popular choices of tourists. In this article such kind of attractions are named resources-based attraction. Based on former study, the paper makes definition of resources-based attraction. Then it selects 509 resources-based attractions as research samples from 671 National AAAA Tourist Attractions, which were authorized by China National Tourism Administration in 2005. By means of GIS spatial analysis tools and some quantitative analysis methods such as NNI (Nearest Neighbor Index), GCI (Geographic Concentration Index), Gini Coefficient and Lorenz Curve, the paper analyses the spatial structure of 509 resources-based attractions and observes their distribution in 8 geographical regions and 31 provinces in China. The result shows that the value of NNI is as low as 0.57, which means the distribution of 509 resources-based attractions is a type of agglomeration. And the distribution of 509 resources-based attractions in 8 geographical and 31 provinces is asymmetric. According to the Lorenz Curve, more than half of 509 resources-based attractions concentrate in 9 provinces, such as Jiangsu and Zhejiang. Changjiang River Delta, Beijing, Xi’an and Luoyang are the places with a high density of resources-based attractions.
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    Attribute Recognition Method of Regional Ecological Security Evaluation Based on Combined Weight on Principle of Relative Entropy
    WU Kai-ya, JIN Ju-liang
    2008, 28 (6):  754-758.  doi: 10.13249/j.cnki.sgs.2008.06.754
    Abstract ( 163 )   PDF (852KB) ( 10 )   Save
    In order to determine indexes weights in regional ecological security evaluation, a weight structure of evaluation indexes consisted of subjective weight and objective weight was presented. The two weights can be computed by using Analytic Hierarchy Process and entropy weight method, and combination weight can be synthesized according to minimum relative information entropy principle. In order to realize the evaluation function of single index evaluation process, a new evaluation method of single index was proposed using attribute recognition model. And then a new model for evaluating regional ecological security, named AR-CWE for short, was established. The result shows that both subjective information of expert experience and objective variation information of samples values can be fully mixed using AR-CWE, and its evaluated results are reasonable. AR-CWE is a general and can be applied to comprehensive evaluation of different security systems.
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    Ecological Vulnerability of Mining Cities in Central Liaoning
    GU Kang-kang, LIU Jing-shuang, WANG Yang, PENG Xiao-li, WANG Ming-quan
    2008, 28 (6):  759-764.  doi: 10.13249/j.cnki.sgs.2008.06.759
    Abstract ( 153 )   PDF (960KB) ( 22 )   Save
    Since the mining cities in Central Liaoning have been important energy production base and heavy industry base in China, the research on their ecological vulnerability will contribute to the improvement of environmental quality and ecological harmony, then we would offer academic basis for the decision-making of sustainable development. Based on the meaning of compound ecosystem in mining cities, we established the indicator system about ecological vulnerability of mining cities in Central Liaoning; put forward the ecological harmony degree; and set up the standards of ecological vulnerability and ecological harmony degree. The results showed that: the ecological vulnerability of mining cities in central Liaoning was in the sub-steady state, the main restrict factors were resources matching index, environmental quality index and economic development index. The ecosystem of it was in the sub-harmony state, of which Benxi was inferior to sub-harmony. The resources matching index in Anshan was inferior to maladjusted, Fushun and Benxi, the economic development index in Fushun and Benxi were inferior to maladjusted, which were the main restrict factors on the harmony development of ecosystems. The vulnerability and harmony degree for the ecosystems of the mining cities in Central Liaoning were well reflected by the model, then we offered their main restrict factors.
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    Application of Fractal Dimension Model for Land Use Study
    LIU Xiao-hui, LU Xian-guo, DONG Gui-hua
    2008, 28 (6):  765-769.  doi: 10.13249/j.cnki.sgs.2008.06.765
    Abstract ( 129 )   PDF (254KB) ( 15 )   Save
    As a case study of the land use types of Zhujiang (Pearl River) Delta, they were based on such data sources as LANDSAT/TM. This paper showed that the value of fractal dimension (D) can be used to effectively characterize the degree of spatial occupation, stability of patch types and change tendency of land use. The results indicated that the values of D of land use types were less than 1.50. With the increase of the value of D, the stable degree of the structure and the spatial occupation degree was decreased and increased respectively. Moreover, the D change of certain land use type reflected the change tendency of this type in different periods from 2000 to 2002. When the D of certain land use type increased, its area also increased; conversely, its area decreased. This paper indicates that D and its change have been effective indices towards the researches of the structures of land use types in Zhujiang (Pearl River) Delta.
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    Images Analysis of Land Use Change and Its Eco-environmental Effects in Wind Drift Sand Region——A Case Study on Yuyang District of the Northern Shaanxi Province
    MO Hong-wei, REN Zhi-yuan, WANG Qiu-xian
    2008, 28 (6):  770-775.  doi: 10.13249/j.cnki.sgs.2008.06.770
    Abstract ( 218 )   PDF (1023KB) ( 26 )   Save
    Based on the remote sensing data, by using the theory of geographic information images and supported by RS and GIS, the land use/cover change (LUCC) images and the ecosystem services value (ESV) change images about Yuyang District during 1985-2000 were constructed. According to the research of above change images, the character of land use change and its ecological effects in research area were analyzed.The results show that the area of unused land decreased, while the area of rangeland, farmland, construction land, forestland and waters increased from 1985 to 2000, and the increased area of rangeland was the most. The most land use changes was the transformation from unused land to rangeland, whose area was 91.14% of the total changes. The change of land use resulted in the ESV of the research area increased from 1927.34?106 yuan (RMB) in 1985 to 2085.93?106 yuan in 2000, which was up 8.23%. There was 85.99% of the total increased ESV in wind drift sand region where the ESV grew 10.88%, but there was only 14.01% of the total increased ESV in loess hilly-gully region where its ESV raised 3.29%. By the empirical analysis, the way of geographic image was a very effective method in analyzing land use change and ecological effects.
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    Digital Extraction of Surface Hydrological Elements from DEM Data in the Wetland Area of a Flood Plain
    ZHOU De-min, CHENG Jin-qiang, XIONG Li-hua
    2008, 28 (6):  776-781.  doi: 10.13249/j.cnki.sgs.2008.06.776
    Abstract ( 166 )   PDF (779KB) ( 120 )   Save
    For study of digital surface hydrological elements controlled by DEM in the wetland area of Sanjiang Plain, Northeast China,both the ArcGIS9.0 Hydro Arc Tools module and the module based on the modified Breaching and Flat Area Algorithm are used to extract the hydrological elements from the DEM data at scale of 1:10000. With the digital method, the study area is delineated into 6 catchments, 82 ponds and depressed low-lying as well as a drainage net-work of both Woyalan River and Nongjiang River. The research indicates that the digital hydrological elements can be extracted successfully from high precise DEM, however, it need to be modified for many times before and after automatic digital extraction due to the problems of digital riverways’ excursion and distortion. For improving both precise and efficiency of digital extraction in the wetland area of a flood plain, some key issues need to be carried out such as development of efficient Algorithms professionally for flat areas and an efficient pretreatment on DEM without loss of key hydrological information.
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    Soil Water Dynamics and Its Exchange with Shallow Groundwater in Sodic Soil Region
    LIU Qiang, HE Yan, ZHANG Guang-xin
    2008, 28 (6):  782-787.  doi: 10.13249/j.cnki.sgs.2008.06.782
    Abstract ( 230 )   PDF (1015KB) ( 46 )   Save
    The soil water dynamics is the precondition to explore the formation and evolution of the sodic soil. Especially, in the shallow groundwater, the exchange of the soil water and groundwater has become one of the main factors to drive surficial eco-environment change. In order to get the dynamics of the soil water in the sodic soil region, the field experiment was conducted in Da’an Sodic Land Experimental Station of China in 2004. The results presented that the ratio of the evaporation to precipitation reached to 2:1 and soil water content changed with evaporation and infiltration processes. As regulated by the shallow groundwater, the soil water was less changeable in the soil layer below 50 cm than in the upper soil layer. Furthermore, influenced by the strong evaporative demand, the exchange between groundwater and soil water reached 11.7:1 and the groundwater has become one of the main water sources to influence the soil water dynamics.
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    Spatial Heterogeneity of Soil Nutrients and Their Affecting Factors at Regional Scale
    YANG Yan-li, SHI Xue-zheng, YU Dong-sheng, WANG Hong-jie, XU Mao, WANG Guo
    2008, 28 (6):  788-792.  doi: 10.13249/j.cnki.sgs.2008.06.788
    Abstract ( 199 )   PDF (355KB) ( 25 )   Save
    The research on spatial heterogeneity of soil nutrients is considered to be an important topic in utilizing and managing soil resources properly. Based on a 1:50000 soil database, spatial heterogeneity of soil nutrients (including total N, total P, available P and available K) at the surface layer (0-20cm) and their affecting factors in the northern Jiangsu Province were analyzed. The results showed that soil total N in the northeastern Lianyungang County, southern Huai’an County and western Yancheng County were significant higher than those in other areas; the total P content tended to increase gradually from north to south and from west to east; the highest available P content was found in the northern Guanyun County and southern Jinghu County; the available K content in the eastern coastal region was significant higher than those in other areas. Soil properties were significantly affected by soil type and parent material. In terms of soil group, bog soils and paddy soils had high nutrient contents. With regard to parent material, nutrient contents were higher in soils developed from lacustrine deposit than those from other parent materials. It was concluded that, at the scale of 1:50000, soil type was the dominant factor for total N and total P, and parent material was a key factor for available P, while soil type and parent material had a little influence on available K, soil type and parent material had stronger impacts on total nutrients than available nutrients.
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    Spatial Characteristic and Influencing Factors of Vegetation Change in north of Hebei Province
    CHEN Hui, LIU Jin-song, WANG Wei
    2008, 28 (6):  793-798.  doi: 10.13249/j.cnki.sgs.2008.06.793
    Abstract ( 137 )   PDF (999KB) ( 11 )   Save
    The study area is located in the north of Hebei Province with a total area of 76 275.6 km2.In recent years, artificial activity changed the land use type and the plant degradation arose the attention of people. This study assessed the trend and spatial-temporal distribution of vegetation index change, which is related with vegetation degradation, in North of Hebei Province using multi-temporal NOAA/AVHRR NDVI data (8 km spatial resolution) from 1987 to 2000 provided by NASA, meteorologic data, DEM data (1:250000) and relative economic data. Results show that the characteristic of NDVI change owing to land cover are concentrative and connective, while the characteristics of NDVI change owing to land use are sparse and scattered. The average change of NDVI is 0.35 for land cover change and the average change of NDVI is -0.17 for land use change and they have contrary change direction. The artificial factors such as the changes of land use or crop type have contribution to NDVI change, but the influence is limited. Precipitation, especially its distribution in growth season is the important influencing factor for NDVI change.
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    Variation of Cr/Cu Ratios in Zhongba Profile and Its Indication on Palaeo-environment over Last 5 ka
    LI Zhong-xuan, ZHU Cheng, ZHU Qing, MA Chun-mei, ZHANG Guang-sheng, OUYANG Jie
    2008, 28 (6):  799-803.  doi: 10.13249/j.cnki.sgs.2008.06.799
    Abstract ( 129 )   PDF (738KB) ( 15 )   Save
    Applying distribution characteristics of chemical elements during soil-forming process to resume palaeo-environmental evolution is a key field in the research of past global changes. This paper divided the continuous strata of the Zhongba site in Chongqing into 12 sub-layers according to cultural sequence over last 5 ka, measuring Rb, Sr, Cr and Cu contents respectively by XRF and ICP-AES methods. Results indicated that Cr has similar chemical nature as Rb with low activity and is apt to deposit in fine sand materials. Meanwhile, Cu and Sr are easy to be transported over the weathering process and enrich in claypan. A linear regression demonstrated that Cr/Cu ratios are positively relative to Rb/Sr ratios. After comparing variation curves of Cr/Cu ratios with climatic records of peat humification in Hongyuan, northeast region of the Tibet Plateau in last 5 ka, they both are well consistent with each other. Therefore, this paper suggested that Cr/Cu ratios as Rb/Sr be a reliable proxy to indicate palaeo-environment even with higher accuratcy. Obviously, Cr/Cu ratios will be significant in geo-archaeological research.
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    Features of Climate Change over the Xishan Island over the South China Sea in Recent 50 years
    LIU Yan-ju, YAN Jun-yue, SONG Yang-ling
    2008, 28 (6):  804-808.  doi: 10.13249/j.cnki.sgs.2008.06.804
    Abstract ( 138 )   PDF (240KB) ( 14 )   Save
    In this paper, the features of climate change over Xisha in recent 50 years have been systematically examined by using the basic meteorological data in 1958-2005. The results showed that annual mean surface temperature rose by about 1.0℃, with a warming rate of approximately 0.19℃/(10 a), which is close to the average value of whole country. The seasonal mean temperature was also on the rise, with the most obvious ascending trend in winter and spring. The annual precipitation had a big fluctuation and no significant trend was seen. For seasonal precipitation, only spring had obvious linear ascending trend. The surface wind speed had a significant trend to decrease, especially in recent 30 years the annual mean wind speed was smaller than the normal year. The wind speed in four seasons also had significant decrease, especially in autumn and winter. Also, the annual sunshine duration, total cloud amount took an significant decreasing trend, while the low cloud amount had a bit increase.
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    Impacts of Precipitation Changes and Human Activities on Annual Runoff of Chao River Basin During Past 45 years
    LI Zi-jun, LI Xiu-bin
    2008, 28 (6):  809-813.  doi: 10.13249/j.cnki.sgs.2008.06.809
    Abstract ( 195 )   PDF (733KB) ( 22 )   Save
    In recent 45 years, the annual runoff of the Chao River Basin has declined significantly with decreasing precipitation and increasing human activities such as hydro projects construction, water diversion and implementation of soil and water conservation. Impacts of precipitation variations and human activities on annual runoff of the Chao River Basin are evaluated quantitatively based on the rainfall-runoff empirical statistical model. The results show: During 1981-1990, 1991-2000, 2001-2005 and 1981-2005, the average annual runoff reduction amounts influenced by human activities are 1.32?108m3, 0.67?108m3, 1.46?108m3 and 1.09?108m3 respectively, taking up 95.1%, 98.9%, 60.7% and 83.2% of the total runoff reduction amounts of corresponding period; the average annual runoff reduction amounts influenced by precipitation variations are 0.07?108m3, 0.01?108m3, 0.95?108m3 and 0.22?108m3 respectively, taking up 4.9%, 1.1%, 39.3% and 16.8% of the total runoff reduction amounts of corresponding period accordingly. The contribution rates of human activities to runoff reduction are much higher than that of precipitation variations.
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    Remote Sensing Analysis of Urban Thermal Environment Changes Under Background of Enhanced Greenhouse Effect——An Example of Dongguan, Guangdong
    DENG Yu-jiao, KUANG Yao-qiu, HUANG Ning-sheng, HUANG jiang
    2008, 28 (6):  814-819.  doi: 10.13249/j.cnki.sgs.2008.06.814
    Abstract ( 159 )   PDF (1230KB) ( 27 )   Save
    As a typical rapid urbanization city, the thermal environment in Dongguan, Guangdong has changed much in the past 28 years because of the economy development, the population growth, the underlying surface change, and the greenhouse effect enhancement. Taking Dongguan as an example, the paper retrieves the land surface temperature using Mono-window Algorithm proposed by Qin Zhihao from Landsat/TM data, meteorological measurement data and basic geographical data. Based on the Vegetation-Impervious surface-Soil model which was proposed by Ridd in 1995 according to the basic elements of underlying surfaces in a city, it defines the typical underlying surfaces as water, high vegetation region and dense building region,and gets the distribution information of them from the threshold division of normalized difference vegetation index. It takes an overlay analysis between the typical underlying surface information and land surface temperature data. The result shows that this method can effectively get the temperature differences of typical underlying surfaces. From 1988 to 2005, the land surface temperature of dense building region is higher than that of vegetation and water in Dongguan. The distribution of high land surface temperature region is consistent with the distribution of dense building region, and the low is consistent with the vegetation and water. Under the background of global warming caused by enhanced greenhouse effect, the temperature difference of dense building region and water, as the same as the temperature difference of dense building region and high vegetation region, are apparently increased. The former is bigger than the latter.
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    Vertical Distribution and Secondary Pollution of Organochlorine Pesticites (OCPs) in Humen Estuary of Pearl River
    YANG Qing-shu, LEI Ya-ping, OU Su-ying, MAI Bi-xian, FU Jia-mo, SHENG Guo-ying, TAN chao
    2008, 28 (6):  820-825.  doi: 10.13249/j.cnki.sgs.2008.06.820
    Abstract ( 130 )   PDF (963KB) ( 28 )   Save
    Six water samples in different depths in water column from Guangzhou channel of Humen estuary in the Pearl(Zhujiang) River were collected, and were filtered by GF/F glass fiber filter. Organochlorine pesticides (OCPs) in particulate and dissolved phase were identified and measured based on USEPA 8000 series methods and under quality assurance and quality control (QA/QC). Concentrations of OCPs varied from 23.89 to 61.69 ng/L. The vertical distribution of OCPs, the partition coefficients (Log Kp) of OCPs between particulate and dissolved phases, and the elevated concentrations of DDTs in the deeper sampling locations in the water column indicated that the inputs of OCPs were different between the surface water and the bottom water in the water column. The inputs of OCPs in the bottom water were correlated with the changes of dynamics in the estuary, and it indicated that the resuspension of surface sediment occurred with the increasing of rapid water current in tide estuary; and the resuspension of surface sediment will induce the secondary pollution of OCPs to the aquatic environment. The results of PCA also suggested that the resuspension of surface sediment existed in a certain hydrodynamic condition at Bai'etan in Humen estuarine of the Pearl River.
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    Methane Flux from Invasive Species (Spartina alterniflora) and Influencing Factors in the Min River Estuary
    TONG Chuan, YAN Zong-ping, WANG Wei-qi, ZENG Cong-sheng
    2008, 28 (6):  826-832.  doi: 10.13249/j.cnki.sgs.2008.06.826
    Abstract ( 196 )   PDF (379KB) ( 35 )   Save
    In 2007, the enclosed chamber technique was used and the measurements on methane flux from Spartina alterniflora were taken during three periods (before the flood, in the course of rising and ebbing tide, and after the ebb) in the Shanyutan wetland which is the largest wetland in the Min River estuary region. The results showed that methane fluxes had obvious seasonal variation. The average methane flux from S.alterniflora before flood and after ebb were 13.12 and 12.94 mg/(m2·h) respectively; the monthly methane flux was lower after the ebb in some months, whereas in other months, emission was either higher after the ebb, or there was no difference; in the course of rising and ebbing tide, the methane flux [3.07 mg/(m2·h)]to hydrosphere was higher than that [2.35 mg/(m2·h)]to atmosphere(p>0.05); the total methane flux to atmosphere and hydrosphere from invasive S.alterniflora patches was 86.86 and 7.84 g/(m2·h)respectively. The correlations between methane flux from S.alterniflora and temperature and salinity were lower, and was higher between methane flux and moisture of sediment (0-20 cm).
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    ANFIS Appraisal of Loess Collapsibility in High-speed Railway Foundation
    Han Xiao-meng, Wang Jia-ding, Wang yu, Chen Yong-jun
    2008, 28 (6):  833-837.  doi: 10.13249/j.cnki.sgs.2008.06.833
    Abstract ( 221 )   PDF (801KB) ( 23 )   Save
    Based on the main factor influencing the loess collapsibility, the data of collapsibility test on collapsible loess foundation in Zheng-Xi High-Speed Railway are collected and summarized, a model of ANFIS based on the index about the loess collapsibility has been established in this paper. Compared the results with the conclusion by the method of multivariate linear regression, it is shown that the ANFIS prediction model could improve the accuracy of forecasting. The results shows that the prediction result after trained and predicted for the samples is in good agreement with the experimental results, and this method is a relatively optimum method for forecasting, at the same time it provides an important viewpoint to explore the collapsibility law on the loess foundation of high-speed railway.
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    Landslide Hazard Evaluation Based on GIS and SVM
    FU Wen-jie
    2008, 28 (6):  838-841.  doi: 10.13249/j.cnki.sgs.2008.06.838
    Abstract ( 180 )   PDF (689KB) ( 23 )   Save
    The development of Geographic Information System (GIS) technology provides a new technical method for the evaluation of landslide risk. Support Vector Machine is the hotspot of machine-learning industry research, and has been applied successfully in many areas. By taking Xianyou County as an example, a new method for landslide hazard evaluation based on GIS and Support Vector Machines (SVM) is presented in this paper. It includes the basic principles and methods of SVM, selection and quantification of landslide hazard evaluation index, foundation of SVM model and the way to realize it. According to the actual situation of the research area, the quantification method has been stipulated separately for each of six selected appraisal indexes including the elevation, the gradient, the slope, the gneiss, the rainfall and the vegetation. The system of landslide geology disaster risk appraisal has been established, the special chart of each appraisal index has been obtained by the use of the geographic information system spatial analysis function. From the results of the appraisal, the extremely high-risk danger and the high-risk danger areas are basically located in the central and northwestern parts of the study area; the secondary risk in both sides of them. This distribution result has basically reflected the present situation of geological disaster in the research area. This method can be put in practice in geology hazard investigation.
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    Regionalization of Spatial Feasible Development on Based Analysis of Eco-economy in Taizhou City
    DING Jian-zhong, CHEN Yi, CHEN Wen
    2008, 28 (6):  842-848.  doi: 10.13249/j.cnki.sgs.2008.06.842
    Abstract ( 184 )   PDF (1053KB) ( 13 )   Save
    The regionalization of potential development under eco-economic approach is a useful way to zone the region for different intensity on behalf of spatial balance for the harmony of population, economy, resources, and environment. emphasizing the adjusting measures to local conditions can decide some areas with low-cost, large environmental capacity to be encouraged for exploitation of industrialization and urbanization while others need agricultural and ecological conservation. It is not only an important foundation of balanced regional development and harmonious spatial order, but also a basic project for the main function regionalization. Meanwhile it is the demand for the various and characteristic development. Based on such conception and recognition, the essay illustrates how to divide the assessed units, choose and manage the assessed elements, and proposes the method of classification matrix integrated the ecological significant value with economic significant value, therefore divides the region into kinds of area with the help of GIS. Finally, according to the regionalization, the essay discusses the method of main function regionalization and the policy guarantee of controlling the regional space.
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