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    Urban and Rural Studies
  • Urban and Rural Studies
    WANG Fa-zeng, GUO Zhi-fu, LIU Xiao-li, ZHAO Wei
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    Zhongyuan urban agglomeration is an important spatial platform advancing "rise of middle of China", also the indisputable main item realizing "rise of the Zhongyuan Plains" in Henan Province. In the integrated development of Zhongyuan urban agglomeration, the construction of the urban system with perfect structure and formidable function is a special important historic task, and the structure optimization of the urban system is a key problem that should be solved properly. The essence of the structure optimization of the urban system is, through government's macroscopic plan regulation and urban agglomeration's integration, to realize the high degree of harmony of the cities with different ranks, different scales and different functions in the spatial platform, thus realizing the promotion of the urban system's overall strength, and finally realizing the sustainable development of urban agglomeration. The primary content of the structure optimization of the urban system in Zhongyuan urban agglomeration is: the rank level optimization, the scale sequence optimization, the function type optimization and the spatial layout optimization. First, the rank level optimization of the urban system. This article uses the law of "city centricity intensity" to divide the rank of all cities in Zhongyuan urban agglomeration, and then constructs four rank levels of the urban system. Second, the scale sequence optimization of the urban system. This article uses the gray system GM(1,1) model, and, according to the status, economic development situation as well as population machinery growth foundation of different cities, to extract the optimized target of the non-agricultural population of various cities in 2020. Third, the function type optimization of the urban system. This article incorporates industries into 8 departments reflecting city function activities, uses Nelson's(H.J.Nelson) statistical analysis principle and method to determine the superiority functions, the prominent functions, the function intensities and the specialization indexes of the cities in Zhongyuan urban agglomeration. Fourth, the spatial layout optimization of the urban system. Around 2020, Zhongyuan urban agglomeration will form an overall pattern of city space layout and function display: "two circles, double nucleuses, four belts and one triangle".
  • Urban and Rural Studies
    WANG Zheng, YANG Nian, HE Qiong, YAO Zi-xuan
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    R&D activities are the most important parts in the progress of innovation, and play a crucial role in the technological innovation. R&D hub, which is a cluster of R&D organizations, firstly appeared in the 1990's. It is not only important to the firms and organizations attached to it, but also may make great contributions to the development of regional economy. The basic conditions which are of great importance to the formation of R&D hubs are analyzed here. This paper classifies the regional conditions which will contribute to the formation of R&D hubs into two types: capital basis and innovative environment. Furthermore, capital basis is divided into industrial base, human capital and social capital; while innovation environment is divided into infrastructure, service sector and institutional circumstances. On the basis of theoretical analysis, the paper compares the basic conditions of Beijing with Shanghai. The indexes chosen include: level of informatization infrastructure, location quotient of high-tech industry, human capital condition and social capital condition. Finally, it comes to the following conclusions: Beijing, which has advantages in human capital, could grow into R&D hub of mixed form, however, it still needs to make great efforts to develop the service industry. Compared with Beijing, Shanghai is not only good at human capital, but also good at commercial elitists and culture. So Shanghai could develop into an innovative R&D hub.
  • Culture and Tourism
  • Culture and Tourism
    YANG Guo-liang, ZHANG Jie, LIU Bo, LI Min, WAN Quanyou
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    The Zipf theory is the law to study the relation between word frequency and word sequence which has been widely used in the fields of urban system, transportation net and metrology. It is also involved in tourist flow, but only used for simple analysis on the ranking of tourist flow size, without deep discussion for the spatial distribution evolution rules of size structure. This paper studied the spatial distribution changing characteristics and the mechanism of tourist flow size by Zipf Rules. It tried to find the changing law of the size distribution to guide the tourism resource development sequence, and to provide new theoretical support for spatial distribution of tourism scenic sites and urban system of tourist nodes. Compared with traditional quantitative method, Zipf theory can be used to judge the non-scaling section of tourist flow size distribution more precisely, and to interpret the varying characteristic of tourist size distribution based on non-scaling section and Zipf parameters. This will provide new quantitative method for the study on the spatial distribution variation of tourist flow. In this paper, Sichuan Province is taken as the study area. From size distribution analysis of domestic and inbound tourist flow during 1996-2005, it proves that the size distribution structure satisfies Zipf law in each year. Based on this result, this paper further analyzed the variation law of non-scaling range, non-scaling section characteristic and internal structure of each non-scaling range on tourist flow rank-size ln-ln graph. The conclusion shows that non-scaling range for both domestic and inbound tourist flow vary identically on ln-ln graph, with a gradually expanding tendency. However, the variation of spatial fractal structure and distribution pattern is not synchronous. From spatial fractal structure, domestic tourist flow size distribution varies from local fractal in 1997 to single fractal of 1998-2003, then to local fractal in 2004 and finally double fractal in 2005, while inbound tourist flow varies from local fractal in 1998 to single fractal in 1999 and till now, without double fractal. The spatial distribution variation also shows the difference: domestic tourist flow is changing from Pareto distribution pattern to lognormal distribution, but spatial distribution of inbound tourist flow is still steady as Pareto pattern. Perhaps the main reason is that the transportation improvement and new scenic sites development has more effect on destination choice of domestic tourists than on that of inbound tourists. This leads to the more apparent distribution variation of domestic tourist flow size structure.
  • Culture and Tourism
    WANG Wei-yan, LIN Jin-ping, SHEN Qiong
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    Since the present stakeholder theory cannot systematically analyse and resolve the problems concerning the relationship of patterns of interest, organizational forms of coordination, and optimized coordination mechanism and trajortories of the stakeholders, this paper, using stakeholder theory in combination with the symbiotic analytical method, defines the key stakeholders in the transboundary ethnic sultural scenic spots and builds models relating to symbiotic relationship and symbiotic models; and, based on the typical case of the Lugu Lake scenic spots, builds a symbiotic game of chess analysis framework in such a kind of scenic spots. The study indicates that the coordinated application of S-S (stakeholder, symbiosis) theory has stronger power of analysis and explanation to the theoretical analysis and diagnosis of the relationship problems of the key stakeholders already occurred in the scenic spots of tourism so as to provide basis for the integration of conflicts and the establishment of coordination mechanism, and moreover, to explore new channels of the theoretical analysis for solving the problems. Specifically, according to the symbiotic theory, the key stakeholder groups in the scenic spots are defined and, in light of symbiotic conditions of the symbiotic units having quality compatible with parameters (e.g. interest), takes it as symbiotic units among the various hierarchies and identifies the symbiotic relationship among them; and then, in accordance with the various types of behaviors spoiling the public interests existeding in the symbiotic models and imperfections of the organizational forms, combining predesigned profits relatively equilibrium goal (such as from P1 to P4, M1 to M4) matching the improved stage interests of Pareto, it is possible to put forward management strategies and improvement schemes corresponding to the optimized symbiosis for the key stakeholders. In view of the philosophy, contradiction is the internal dynamics and necessary product of objects development.It is just because of the emergence, mitigation and elimination of the contradictions and conflicts as well as their reemergence, remitigation and reelimination in the symbiotic status that makes this process not only keep a reversible state but what is more, makes us find out internal law and mechanism from it. The is of certain theoretical value and profound practical significance to the construction of harmonious society and harmonious culture and getting rid of the "one lake, two management schemes" of Yunnan and Sichuan provinces as well as bidding for world natural and cultural heritage of the Lugu Lake.
  • Economy and Regional Development
  • Economy and Regional Development
    GUAN Wei
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    Rapid development of economic society benefits the human race, but deteriorates basin environment to a certain extent. At present, the shortage of water resources and the pollution of water environment affect the development of human society, economy and culture seriously. It is very important and necessary to enhance sustainable usage of water resources and ensure sustainable development of economic society. The traditional management theory on complex water environment and resources system understands the integrated management model incorrectly and neglects the fuzziness both in the thought of human being and objective phenomenon. Based on the theory of Engineering Fuzzy Sets suggested by Professor CHEN Shouyu, a new assessing method and its corresponding model for assessing the Liaoning provincial sustainable development degree is proposed and the procedure for calculation is presented in detail. Firstly the paper discusses the relationship of aquatic economy-ecosystem environment-economic coupling system and the sustainable development mode of this coupling system, and brings forward sustainable development degree measuring sustainable development status with fuzzy mathematics subjection degree. Secondly, the paper discusses the sustainable development assessing method of the complex water environment and resources system. The author thinks that the relative membership degree of Fuzzy Sets can be used to describe the sustainable development situation. The paper gives the definition and the calculating method of sustainable development degree. The author studies the sustainable development degree of Liaoning Province, researching the relationship between sustainable development of water resources and economic society, considering the present situation of water resources in Liaoning Province. The result shows the sustainable development ability of water resources is low (the sustainable development degree of water resources in Liaoning Province is 0.2456), and there are some exploring potentials and advancing space. The case study shows that the proposed method is more reasonable and its calculating method is very simple. It can also be used in various assessment fields. The result verifies that the method and its corresponding model are reliable and easy to be used. At the same time, the study can also provide decision-making support for sustainable usage and management of water resources in Liaoning Province.
  • Economy and Regional Development
    OU Xiang-jun, ZHAO Qing
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    Through the analysis of related literatures at home and abroad, we found that there is no uniform conclusion on the researches of regional economic disparities in Jiangsu province up to now. And quantitative comparison researches of its causes were rarely involved. Using gross domestic production per capita as a variable indicator to measure regional economic disparities and taking 67 cities and counties in Jiangsu province as geographic study units in this paper, we made a quantitative analysis of measuring the total level and the variety characteristics of regional economic disparities in Jiangsu with Gini coefficient and Theil index. Both methods show that regional economic disparities experienced the period of "drop-rise-drop again-rise again" process while the total regional economic discrepancy expanded significantly since the starting of economic reforms of 1978 in China. From the decomposition of Theil index, we found that overall regional disparities in Jiangsu province have shifted from rural-urban to intra-rural disparities. Meanwhile, the interregional inequalities among the southern Jiangsu(Sunan), the central Jiangsu (Suzhong) and the northern Jiangsu (Subei) were expanding. On this basis, we analyzed the factors of the formation and transformation of regional economic disparities in Jiangsu province, such as historical development foundation, economic geographic conditions, regional development strategy, industrial conversion capabilities, development of township enterprises, economic globalization and level of market maturity. Using regional separation index recently developed measures based on regional inequality decompositions, this paper makes a quantitative analysis of the agents of regional economic inequality and argues that the level of market maturity, industrial conversion capabilities and the regional development strategy are the main factors for the expanding of the regional economic disparities in Jiangsu province.
  • Economy and Regional Development
    WANG Yi-hu, CHEN Wen, CHEN Jiang-long, DUAN Xue-jun
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    The environmental pressures on industrial firms, involving government, public and market etc. , come from exterior of the firms and force the firms to improve their environmental behaviours. The industry in Jiangsu Province along the Yangtze River has been developing rapidly in recent years, and thus inducing many environmental problems. The increasing environmental problems in consequence enhanced the environmental pressures on the industrial firms from exterior. In order to get insight into the structure, degree and changes of environmental presures on the firms so as to adjust and innovate the environmental policies for enhancing industrial greening, this article studies the impacts of all kinds of environmental pressures on industrial firms and their contributions based on dataset of questionaire from concerning firms with LISREL model. This study revealed that in the study region the pressure from government administration is still the main pressure to the industrial firms, and the improvement of the environmental behaviors of industrial firms is also made by the force of government. Although it is becoming more and more important, the pressures from market, especially the pressures from domestic market have not been the main ones to the industrial firms, and the pressures from the public are also very weak. But in the developed countries, the pressures from market and public are the main environmental ones to the industrial firms. Therefore, there is a long way for China to go to adjust the structure of environmental pressures. In the future, necessary measures should be taken to improve the environmental pressures from market and the public while with the pressure from government administration being sustained.
  • Economy and Regional Development
    ZHANG Bing, JIN Feng-jun, YU Liang
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    Based on the "shortest path matrix", with the indexes "weighted mean travel costs" and "economic potential", the author studied the optimization of highway network in Hunan province and the evolution of spatial pattern from 1984 to 2004.With the economic accessibility and the index of "economic potential" it is possible to analyze the spatial pattern effectively through the changes of transportation network; it is beneficial to organize the urban and regional spatial structure, which will support the region's exploitation and the transportation's organization.The study result is that from 1984 to 2004, the accessibility of the highway network in Hunan province was a "core to edge" spatial configuration.The accessibilities isolines have been relaxed. The "CHANG-ZHU-TAN" region is a stronger core and the Yueyang county, Huaihua and Jishou are weak in the spatial configuration. From 1984 to 2004, the disparity of the absolute accessibility was reduced, and that of the relative accessibility became increasingly. The changes of economic potential reducing followed the transportation lines, and took as a "hand-shape". According to the "weighted mean travel costs" and "economic potential", the author divided the Hunan province into four categories of counties: the best development region, the better development region, the popularly development region and the worse development region. The accessibility shows the spatial configuration with a "point-axis" sign in 2004, which is contrary to the "lower-level and out-of-order" in 1984. In the future, the government should develop the "CHANG-ZHU-TAN" region and "one point and one line" regions, which will promote the fast Hunan provincic economic level greatly and form the economic channels in the eastern part of Hunan province. At the same time, the government should make great efforts to improve the accessibility in the western part of Hunan province, narrow the big gap of the economic development level in the province, thus being beneficial to the optimization of the spatial pattern in a "balanced and ordered" state.
  • Economy and Regional Development
    CHU Bo, LIANG Jin-she
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    It is significant for regional development whether the distribution of manufacturing industry is rational or not. Based on data from the census of Beijing's basic units in 1996 and 2001, this paper, with the Ordered Probit Model (OPM) and analytical techniques in Geographical Information System (GIS), attempts to probe into how the location factors impact the manufacturing industry in Beijing these years, as well as the changes of the impacts. On the one hand, through these studies concerned with a special region, the capital, it might offer the development of Location Theories some material, and it also helps to promote the practical application of the OPM; on the other hand, the studies' findings can be useful references to both the adjustment of industrial distribution and the planning of industrial development in Beijing in the future. The findings suggest that:(1) Beijing's manufacturing industry is being in the course of developing towards outer city and suburbs, and that development trend accords with the characters of Beijing's resources, environment and economy, which is an optimization of the spatial distribution pattern.(2) The OPM's results validate findings (1), and reveal that labor factor, enterprise factor, industry factor, convergency factor, and geography factor have different effects on the locational behaviors.(3)The laborers' quality plays a vital part in Beijing's manufacturing industry's spatial distribution, and in order to maintain the higher level of industrial structure, Beijing should improve the laborers' quality in the outer city and suburbs, which are the most important viewpoints of this study.
  • Environment and Ecology
  • Environment and Ecology
    CHEN Hao, FANG Hai-yan, CAI Qiang-guo, ZHOU Jin-xing, HUANG Xin
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    Soil erosion and eco-environment on the Loess Plateau are among the most serious problems in the world.To improvements of the vegetation coverage and ecological efficiency are the key issues to be settled urgently in future in the context of erosion control and food security. According to the data from the key counties with different spatial locations on the Loess Plateau, the effects of climate, land cover and land use pattern on sediment yield as well as the relationship between sediment yield and environmental variables are studied in this paper. The integrated impact by natural variables and human activities and their weights in influencing sediment yield are also quantitatively analyzed on the Loess Plateau, particularly in the sandy and coarse sandy areas. Furthermore, the adaptive coefficient of eco-water requirement of natural vegetation and the concepts of restoration degree of forest and grass are used to systematically discuss the macro-configuration changes of land use pattern and vegetation restoration prospect in the middle Yellow River, particularly in sandy and coarse sandy areas. Studies indicate that on the Loess Plateau, where the growth of vegetation mainly depends on natural precipitation, biological measure (mainly vegetation type) is required to be in accordance with natural zone, and the restoration and construction of macro-vegetation should adhere to the vegetation restoration degree and its adaptive coefficient of eco-water requirement. With the pressure of growing population, it is a key problem to reconstruct vegetation and crop planting to settle out the contradictions, such as properly dealing with the relationship of economic development and environmental protection, reducing reclamation rate and protecting farmland, planting forest and making grass and their adaptative to precipitation as well the reasonable configuration of biological and engineering measures on the Loess Plateau.
  • Environment and Ecology
    ZHENG Ming-guo, CAI Qiang-guo, CHENG Qin-juan
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    The loess gullied-hilly area of the Loess Plateau in North China is one of the most severely eroded regions in the world with a mean annual soil loss rate exceeding 10000t/km2.Based on the observed data here from two stations, the relationship between runoff and sediment yield is examined for single storm events. In the study area, sediment concentration keeps stable when flow discharges are in excess of some critical values, and mean sediment concentration for single flood events mainly depends on the heavy-discharge stage in flood duration. Thus, the mean sediment concentration also keeps stable for heavy flood events. Therefore, one new runoff-sediment relationship model is established for specific watershed:M=Ch,where M is area-specific sediment yield, h is runoff depth. Furthermore, this model has excellent applicability due to the importance of extreme events for soil loss in the study area. The results of the model applied to the annual timescale showed that the model can predict the annual sediment yield very well for the watershed without base flow; and for the watershed where base flow exists, the model can also obtain a good estimation in wet year using the total runoff volume occurred in flood season.
  • Environment and Ecology
    ZHANG Ji-quan, LIU Xing-peng, TONG Zhi-jun
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    With the development of disaster research and economy, disaster risk assessment has become a new research area, which will help decision makers to choose optimal technical policies to manage disaster and to set up disaster mitigation strategies. As one of the important natural disasters, the grassland disaster has greatly influenced the development of stockbreeding. So it is necessary to research on grassland fire risk. The grassland in the western Jilin province is an important one in China, which belongs to Songnen grassland in Northeast China, and is also a region susceptible to fire. According to the statistics, the fire disaster in the grassland in the western Jilin province occurred 142 times and affected an area of 7095.5ha during the period 2001-2004, thus seriously threatening and restricting sustainable stockbreeding development in the region. In terms of natural disaster generating mechanism and risk analysis formula, the grassland fire disaster risk index (GFDRI) is set up based on the analysis of grassland fire disaster, exposure, vulnerability and emergency response and recovery ability by using linear weighting model, analytic hierarchy process (AHP) and grassland disaster risk evaluation model. The risk values of grassland fire disaster are calculated respectively in the western Jilin province. The study area was divided into four risk regions, namely, extremely heavy, heavy, moderate and light.The results are proved to be higher reliable.This study is can provide reference and guidance for grassland fire disaster insurance, managing grassland fire disaster and developing strategies to mitigate grassland fire disaster and reduce losses from it. Because grassland fire disaster was influenced by many factors, the index such as vegetation and terrain should be taken into account when the study is carryied out in other place where the terrain changes sharply and the vegetation varies. At the same time, the index value should be changed correspondingly. In the further research the spatial data should be applied to describe the distribution and variety of grassland fire risk.
  • Environment and Ecology
    ZHAO Jing-bo, SUN Gui-zhen, YUE Ying-li, CHEN Bao-qun
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    Moisture content change and characteristic, distribution, formation reason of dried earth layer under artificial forest land and lawn ranging 0~6m depth in Guanzhong Plain were studied in this article by drying-weight method.The aim of the research is to verify the distribution scope of dried earth layer in the south of the Loess Plateau and the reason of it, and to provide scientific basis for the prevention and control of dried earth layer. Experiment results show that the average earth moisture content is 8.4% between 2 and 4m of 10 age apple trees, the average earth moisture content is 9.0% between 2 and 4m of 12 age phoenix trees in Xianyang. The average earth moisture content is between 9.3% and 9.5% between 1.8~3.6m of 12 age phoenix and poplar trees in Lantian. The average earth moisture content is 9.2% between 2 and 3.5m of 15 age apple trees in Wujiafen, and there is formation of dried earth layer between 2 and 3.5m. There is obvious formation of chronic dried earth layer in artificial forest land at Xiekou of Lintong and Weiqu of Chang'an.The average earth moisture content is more than 12% below 4m of the middle age artificial forest land, which indicates that the dried earth layer doesn't extend to the layer below 4m.The average earth moisture content is more than 12% below 2m of 6 age and 4 age apple trees land, and there is no formation of dried earth layer. According to the computation of CaCO3 migration depth model, under 600mm annual precipitation condition in Guanzhong Plain, the migration depth of gravity water is less than 4m, which indicates that the dried earth layer in this area is chronic. The changes of the moisture content of the artificial forest land show that the dried earth layer is distributed extensively on the Loess Plateau, and the south boundary of it has reached the northern foot of the Qinling Mountains.In Northwest China, where annual precipitation is less than 600mm, the dried earth layer in the artificial forest land is a universal natural phenomenon. The formation reason of the dried earth layer is that the gravity-capillary zone depth, which is determined by precipitation, is obviously smaller than 2 m.The direct action of water factor of dried earth layer is that the buried depth of the zone is small and the water movement velocity is slow, while the high water consumption tree species is the vegetation factor of it. It is clearly shown that the depth of the gravity water and the capillary water in Guanzhong Plain is the main natural factor for the formation of the dried earth layers. Whether the artificial forest or natural forest, the dried layers generally develop in the middle age forest land. The formation of the dried layer doesn't mean that the forests can not develop in this area, but they cannot develop well.Trees can be planted in areas where dried earth layer developed poorly, but they are not suitable to be planted in areas where dried earth layer developed intensely.
  • Environment and Ecology
    NIU Jun-jie, ZHAO Jing-bo, WANG Shang-yi
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    This article is a research report of soil desiccation based on our research of the soil in which the artificial poplar woods and the apricot woods have been growing for over 30 years in Jingle, Loufan, and Lanxian counties of Shanxi Province, which are the key sites of environmental ecological administration in the upper reaches of the Fenhe River.820 soil samples were separately taken from the depth of 0-600cm at 14 sampling points.The soil moisture data sequence in these sampling points was obtained. The different ages of the woods and the different water consumption of different vegetations in different places and vegetal periods were analyzed.The research results are: that in the soil 2-4m underneath the 10-year-old poplar woods was 9.89% in Loufan County, and in the soil 2-4m under the 20-year-old poplar forest was 7.88% in Loufan County, the average water content in the soil 2-4m beneath the 18-year-old poplars was between 7.27% and 8.83% in Lanxian County; the average water content in the soil 2-5.7m under the 30-year-old poplars growing on the sunny slopes was 9.02% and on the shaded slope 2-4m underneath the forest was 9.72% in Jingle County. All these indicated that the profiles of the soil reveal the features of light or medium development of dry layers.It is concluded that development of dry layers is universal in the soil under the artificial woods of the upper reaches of the Fenhe River.Terrain, climate and vegetation have exerted great impacts on the development of dry layers.Generally, soil desiccation in artificial forestlands on the ridges and loess hills are more intense than those on the low-lying and gulch locations.And soil desiccation on sunny slopes are more intense than those on shaded slopes.Scarce natural precipitation is an important factor accounting for the formation of the dry layers. It is proposed, from the perspective of vegetation suitability, that the law of vegetation development should be followed, grain-for-green programs be scientifically performed, ecological special zones be established, scientific eco-environmental programming in the upper reaches of the Fenhe River be conducted, and measures such as planting drought-enduring and low water-consuming sparse woods be taken in areas where light dry layer developed and served as source area to conserve water supply and provide drinking water for Taiyuan City.This research is expected to offer the theoretical basis for ecological recovery of this area.
  • Environment and Ecology
    LIANG Tao, CAI Chun-xia, LIU Min, PENG Xiao-lei
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    Landuse ecological suitability assessment is very important in urban ecological planning. It is essential for this integrative approach that environmental aspects are incorporated into the planning process at an early stage, instead of being evaluated afterwards.This paper describes a methodology that incorporates ecological and environmental aspects in urban planning processes. Based on the functions of spatial data analysis and digital picture visualization of ArcGIS 8.3, a practical method of ecological suitability assessment of urban landuse was supplied. Pingxiang in Jiangxi province was taken as an example and applied to assess the ecological suitability of its urban landuse. With this method, the main urban landuse types were selected firstly and then factors of ecological suitability assessment were chosen. Furthermore, single factor assessment on all urban landuse types was carried out. And then weights of all factors were determined by hierarchical analysis. Through overlaying of all single factor assessment layers, map of ecological suitability assessment of urban landuse could be generated. This easy-use assessment method aims to support the work of local authorities and urban planning offices, especially with regard to identifying options in the early phases of the landuse planning process.
  • Environment and Ecology
    GUO Huai-cheng, HUANG Kai, LIU Yong, YU Ya-juan
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    As the ecotone of the aquatic ecosystem and terrestrial ecosystem, riparian ecosystem has unique vegetation, soil, topography, geomorphology and hydrology features and a series of environmental, social and economic functions. Hence to improve the management of resources, ecology and environment of the riparian ecosystem for sustainable development of watershed has become a significant issue in the watershed ecology and ecosystem ecology. The characteristics of the riparian ecosystem were analyzed. The riparian ecosystem was the result of three-dimensional interaction between terrestrial ecosystem and aquatic ecosystem. As a typical ecotone, the frequent anthropogenic disturbances, geomorphological process and hydrological process could influence the riparian ecosystem in the ecological process and species succession. According to the aim of ecosystem management, the uniqueness, complexity and dynamics of the riparian ecosystem should be taken into account. After introduction of the progress in the riparian ecosystem management, the concept and elements of the riparian ecosystem management were defined. A practical process for riparian ecosystem management was given in this paper, which consisted of seven steps. The first one is scoping of object, area, stakeholders,etc. , then comes to the problem diagnosis. The third step is goal setting, including broad and operational goals. After the above processes, the riparian ecosystem was integratively assessed, in which ecosystem health and integrity were taken as indictors for assessing ecosystem structure, and ecosystem service was valued to reflect ecosystem function. The management policy and its implementation was the sixth step, which was the most important one in this process, and feedback and adaptive adjustment was the last step in the process. Four key problems were identified for riparian ecosystem management,including the research scales, the riparian width of management, the coordination of ecological values and local riparian ecosystem management. According to the developments and present studies on the riparian ecosystem management, the theory of the riparian ecosystem management, induction of ecological model, application of the interdisciplinary approaches, application of the 3S technologies and modern mathematics method as well as quantitative case study should be the front problems for further studies of the riparian ecosystem management.
  • Environment and Ecology
    GAO Jian-hua, YANG Gui-shan, OU Wei-xin
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    The influence, after introduction of Spartina alterniflora,on the distribution of TOC, TN and TP in tidal salt marshes in north Jiangsu Province,is analyzed. The result indicates that, the unit area accumulation of TOC, TN and TP within the depths of 0~20cm, as well as average horizontal and vertical contents of TOC and TN, in Spartina alterniflora marshes, are higher than those in other ecological zones, and decrease from Spartina alterniflora marshes to Artemisia schrenkiana marshes, Phragmiues auszradis marshes and silty marshes. While the highest average horizontal and vertical content of TP occurs in silty marshes, and the average content increases from land to sea. In autumn, the unit area accumulation content of TOC of Spartina alterniflora is 14.1 and 1.9 times that of Artemisia schrenkiana and Phragmiues auszradis, respectively. Similarly, the unit area accumulation content of TN of Spartina alterniflora is 32 and 1.6 times that of Artemisia schrenkiana and Phragmiues auszradis. The unit area accumulation of TP of Spartina alterniflora is also larger than that of Artemisia schrenkiana and Phragmiues auszradis, its content is respectively 56 and 3.9 times that of Artemisia schrenkiana and Phragmiues auszradis. The influences, after introduction of Spartina alterniflora,on the distribution of TOC, TN and TP in tidal salt marshes are: (1) The accumulating rate of Spartina alterniflora is high, which benefits the preservation of nutrient matter, and the increase of accumulation contents of TOC, TN and TP in the whole tidal salt marshes;(2) changes of plants distribution pattern in tidal salt marshes induced by Spartina alterniflora, accordingly heighten the accumulations of TOC, TN and TP in the whole ecosystem; (3)the high production and enormous belowground biomass of Spartina alterniflora, influence not only TOC, TN and TP cycling in the inner ecosystem, and the exchange between the adjoining ecosystem, but also accumulations of such three matters in the whole tidal salt marshes;and(4)Spartina alterniflora demands abundant P during growing process because of its vegetative characteristics, and the content of TP in sediment of Spartina alterniflora marshes is continuously decreased during its movement from land to sea. Therefore, the content of TP in silty marshes is higher than that in other ecological zones.
  • Environment and Ecology
    YU Wen-jin, ZOU Xin-qing
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    The vertical distribution law of heavy metals of Pb, Cu and Zn from Wanggang tidal flat and status of its pollution were studied. The background value of Wanggang 210Pb is measured, which is 1.116dpm/g. It was suggested by the study that the modern average rate of sedimentation in Wanggang tidal flat is 4.13cm/a. It was found that the vertical changes of heavy metal content of Wanggang tidal flat have the same homoplasy, that it reduces from surface layer to bottom step by step, in accordance with granularity. This argued more obviously the conclusion summarized previously that heavy metals and granule sediment have good relativity. The common rule that the content of heavy metals was in the order of high tide>middle tide>low tide has straight correlation with the process of water dynamics. It was deduced by the relativity of heavy metals that the Fe,Cu,Pb,Zn and Li have better relativity. Thereinto the relation of Fe, Ni and Cr was very marked, exceeding 0.900. It was obvious that the vertical changes of heavy metals were relatively stable and possibility came from rock. Pb,Cu and Al have minus-correlations with Fe,indicating that Pb and Cu of Wanggang tidal flat were impacted by anthropogenic activities to a greater degree. The Cu and Zn normalization value in 15 years is stable in contrast to that of Pb. The undulating scope of Cu is between 0.4 and 2 and Zn is between 1.5 and 2.6. But Pb has a greater scope. Using Hokanson's latency ecological risk index method, it was deduced that the latency ecological risk index of Pb, Cu and Zn was less than 95, an indication of light harmfulness. But it had pollution of Pb and Cu by all means in this area. Pb was the main pollution factor in the estimated area.The application of pesticide and fertilizer was the main reason of heavy metal pollution. It is suggested that the heavy metals in Wanggang tidal flat come from pollution of land-based farming activities.
  • Climate and Global Change
  • Climate and Global Change
    LIAO Yong-feng, WANG Wu-yi, ZHANG Li, YANG Lin-sheng
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    With the stratospheric ozone layer turning thinner and thinner, to calculate solar ultraviolet radiation reaching the Earth's surface and assess its effects on human health has become a focus. Based on radiation transmission model of DISORT, a new method to calculate biologically effective ultraviolet radiation intensity on the ground is identified and spatial distribution of biologically effective ultraviolet radiation intensity in China in January and July,2000 is simulated using UVSPEC model of LibRadtran software package and GIS spatial analysis technique.This paper discusses the effects of the spatial and temporal variation of atmospheric ozone, cloud cover and ground albedo on ground ultraviolet radiation intensity, and explores the correction method with the result of DEM and cloud cover. In addition, it systematically analyzes the spatial distribution characteristics of ground biologically effective ultraviolet radiation intensity in China in January and July, 2000. Ultraviolet radiation intensity is higher in low latitude than that in mid-high latitude in January and on the contrary in July. Because of the higher altitude and lower ozone thickness, the ultraviolet radiation intensity is higher on the Tibetan Plateau than in the other regions in January. There are different radiation intensity distribution patterns between UVA and UVB in January and July because ozone can absorb more UVB radiation than UVA. Higher radiation distribution of UVB is closer to the low latitude than that of UVA. Owing to the higher relative spectral effective coefficient against 270nm of UVB, normalized UVB biologically effective radiation is about six times more than that of UVA.
  • Climate and Global Change
    HAO Zhi-xin, GE Quan-sheng, ZHENG Jing-yun, LI Yan-qi
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    Drought is one of the most damaging climate-related hazards to impact societies. Although drought is a naturally occurring phenomenon throughout most parts of the world, its effects have tremendous consequences to the physical, economic, social, and political elements of our environment.The typical severe drought of Chongqing at the last 100 years occurred in 2006, which was characterized by the most serious drought rarely seen in history in terms of long duration, high temperature intensity, water resource scarcity in combating drought, extensive disaster-affected areas and heavy losses.Here the climate background of severe drought was analyzed, and the comparison and assessment was made with the drought events which occurred in history, using the recorded historical documents in the last 1000 years. The analysis on the historical drought records in Chongqing for the past 1000 years showed that the "extreme drought" event in 2006 has occurred several times in Chongqing and its surrounding areas in historical periods, and was not the only one of many. The extreme climate event was not beyond the normal climatic fluctuation in the duration, impact and spatial coverage of this drought.The severe drought event occurred in Chongqing in 2006 reminds us that the global warming might lead to the significant increase in the frequency of the extreme warm event, and the similar disasters may occur usually. So the extreme event and its adverse effect in the context of climate warming is one of the scientific key issues, hence it is necessary to pay more attention to that in the future.
  • Climate and Global Change
    FENG Xin-ling, LUO Long-cheng, QIU LI-li, FENG Zi-li
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    The precipitation climatic change includes the changes of the rainfall and the rainy days. Rainy day change is an important constituent of the precipitation climatic change. Under the background of the temperature rising and the climatic warming, how will the rainy days be able to change? This problem belongs to one of the important contents on global climatic change research. The author studied the regional change, the tendency change and the future change of the annual rainy days of China. Using the rainy day data from 1951 to 2002 at 194 meteorological stations of China, the author studied and forecasted climatic change tendency of annual rainy days in five regions of China with the basic principle of the fractal theory, R/S analytic method. The study indicates that, there is a similarity between future change tendencies of annual rainy days in five regions with that of the past 50 years. In order to make an in-depth study of the future change of rainy days, this study designed two items of Hurst Index experiment and inferred the changing tendency, the transition and the sudden change of rainy days with the corresponding relation between two experimental results and the annual changing tendency of the rainy days. The result indicates that the annual rainy days have the completely consistent tendency to reduce in five regions of China, but the change of rainy days shows a remarkable regional differential characteristic. The rainy days will reduce 6.8 days every ten years in the next ten years in the north of Eastern China and 5.9 days in the south of Eastern China. The reduction of that of Sichuan Basin is the most, which will be 12.3 days every ten years, the Tibetan Plateau and Western Sichuan Plateau are the least, which will be 3.7 to 3.8 days but be not stable. There is the transition of climatic change in five regions of China, but there is no sudden climatic change of rainy days in this period.
  • Climate and Global Change
    YAO Yu-bi, DENG Zhen-yong, YIN Dong, ZHANG Xiu-yun, YANG Jin-hu, CHEN Chang-ping, AN Hua-yin
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    Using main meteorological and eco-environmental observational data in the Yellow River important water source supply area of Gannan Plateau,the climatic change characteristics and eco-environmental effects of this study area were analyzed. The results show that the interannual variation of precipitation tended to decrease, and the variability is -22.6~-9.6 mm/10a.In the 1980s the sudden change phenomenon in precipitation took place, in addition the 6~7a and 15a main periods of oscillation exist in most parts of the study area; temperature displays a remarkable increasing trend with an increasing rate higher than that of the whole country, in terms of seasonal changes, the increasing rate of winter is higher than that of the other seasons, in the 1970s the sudden change phenomenon in temperature took place with a persistent ascendant trend after 1980; water resource shows a significant descendant trend, the valley precipitation presents a remarkable positive correlation with the water resource, and the valley drought index presents a remarkable negative correlation with the water resource, the decreasing precipitation and increasing drought index result in a decrease in water resource; theoretically the domestic animal capacity of the regional savageness grassland is 428.82 ten thousand sheep, but in fact the over loading rate reaches 96.39%; climate changes is the natural factor for plain ecological degradation, but overgrazing, excessive tree felling and grass cutting, artificial destruction, biological chain unbalance and so on are the artificial factors for plain ecological degradation, water resource sharp decrease, diversity of biology decrease and eco-environment degradation are the combined effects of the above two factors in the Yellow River important water source supply area of Gannan Plateau.