Loading...

Table of Content

    25 September 2004, Volume 23 Issue 5 Previous Issue    Next Issue
    Original Articles
    On the Factors and Prediction Models of SDR
    CAI Qiangguo, FAN Haoming,
    2004, 23 (5):  1-9.  doi: 10.11820/dlkxjz.2004.05.001
    Abstract ( )   PDF (1103KB) ( )   Save

    Sediment delivery ratio is one of the sediment yield predicting methods, which is wildely used in the world now. In this paper, main research achievements in sediment delivery ratio are summarized. The relationships between sediment delivery ratio and the influencing factors such as drainage area, rainfall/runoff, sediment particle size, geology and physiognomy are analyzed, and the research progress in sediment delivery ratio predicting models is analyzed too. Although some excellent results have been gained, on the whole, most of the sediment delivery ratio models are qualitative or semi-quantitative, and there are different viewpoints on the sediment delivery ratio model building. So the research on the sediment delivery ratio is still immature now. According to the practical situation of the sediment delivery ratio research in China, some tentative plans are proposed in this paper. First, more influencing factors should be explored because sediment delivery ratio model building for the sediment delivery ratio can been influenced by several factors and in different time and space the main influencing factors are different. Second, to promote the application range of the sediment delivery ratio model, the physical process of sediment delivery in slope and in riverway should been profoundly studied. Finally, the sediment delivery ratio has only been researched in Yangtse Rive Basin and Yellow River Basin in China, other important rivers in China still need to be studied in future.

    References | Related Articles | Metrics
    Research of Land and Ocean Interaction of the Coastal Zone in South China
    DAI Zhijun, LI Chunchu, CHEN Jinhui
    2004, 23 (5):  10-16.  doi: 10.11820/dlkxjz.2004.05.002
    Abstract ( )   PDF (957KB) ( )   Save

    It is a fact that the key of the Land-Ocean Interaction (LOI) research focuses on coastal zone, a significant interface of the global system between land and ocean under current global changes. This paper firstly reviews in brief the research work on historical interactions between Land and Ocean of the Coast in South China (ILOCSC), which mainly includes two schools, the vicissitude of holocene shorelines and the evolution of sand- banks. Then, this paper analyses and discusses native studies on the modern ILOCSC including the evolution of coast and beach. Finally, based on above analyses, this paper raises main topics concerning the central contents and the general tendency of ILOCSC studies in the future as follows: (1) The response of geomorphologic configuration, sediment structure and beach state in South China coast to monsoon climate in East Asia and the information preservation of this response. (2) Comparative research on the modes of the dynamic geomorphology of the different coastal type in response to the various dynamic actions of land and ocean. (3) The mechanism analysis of dynamic action between land and ocean of the arc-shaped coast in South China. (4) Research and discussion on how to simulate and forecast shoreline deformation and the configuration of equilibrium profiles of the beach. (5) The processes of the adaptation and response of the coast in South China to the global changes, and the countermeasures on the problem of the sustainable development and the protection of the coast.

    References | Related Articles | Metrics
    Indicator System on Dike Breach Risk Evaluation for the Lower Reaches of Yellow River
    XIA Fuqiang, KANG Xiangwu, WU Shaohong, YANG Qinye, MA Xin, LIU Ziqiang
    2004, 23 (5):  17-24.  doi: 10.11820/dlkxjz.2004.05.003
    Abstract ( )   PDF (990KB) ( )   Save

    The lower Yellow River is characterized a "Hang River". It deposits seriously at all times. It changed its course and breached frequently, and gave rise to great calamity to the Chinese People, especially in Henan and Shandong provinces. The risk of dike breach in the lower Yellow River, which is developing now, is a serious threat to people's life and property safety in the central China always,so it is of great significance to establish the indicator system to evaluate the risk of dike breach. By analyzing the environmental characteristics in the lower reach of Yellow River, especially its geology structure, the importance of flood factors and the mechanism of different dike breach pattern , a systematic evaluation indicator system of dike breach risk in the lower Yellow River is established. Some viewpoints on dike breach risk evaluation are put forward in this paper:1. Putting the factors of flood condition into the risk evaluation indicator system. 2. The breach risk evaluation indicator system includes two parts, namely, environmental background evaluation of geology structure and scenario evaluation of dike breach. 3. The scenario evaluation of dike breach links up with the pattern of dike breach. It is very important to prevent and control flood. 4. The dike breach evaluation factors and indicators is selected and decided according to the mechanism of dike breach pattern.

    References | Related Articles | Metrics
    Modeling Optimal Allocation of Arable Land in Relatively Developed Areas ——A case study in Wuxi City, Jiangsu Province
    LIU Yansui, HU Yecui, ZHENG Yu
    2004, 23 (5):  25-32.  doi: 10.11820/dlkxjz.2004.05.004
    Abstract ( )   PDF (1003KB) ( )   Save

    Rapid industrialization and urbanization have worsened the shortage of arable land resources in relatively developed coastal areas of China. It is important to study how to rationally allocate the quantity of arable land allowable for conversion into urban uses to maintain a sound eco-system both scientifically and practically. We constructed a Model of Allowable Conversion (MAC) of regional arable land resources after analyzing the characteristics of land resources changes, and studying the relationship between these changes and the demand for urban land use during the process of industrialization and urbanization in Wuxi city. With the assistance of the MAC we determined the maximum amount of arable land resources that is allowed for conversion into non-farming uses in the next 30 years. The idea of quantifying the allowable conversion of arable land resources will help accelerate the process of industrialization and urbanization while arable land resources are adequately protected. Through determining a threshold quantity of allowable conversion of arable land resources during industrialization and urbanization, we solved the problem of how to optimally allocate regional land resources for multiple and even conflicting demands for land resources.

    References | Related Articles | Metrics
    Response of Land Utilization in Resource-rich Cities to Wetland Ecology Safety: A Case Study of Daqing in Heilongjiang Province
    ZANG Shuying, NI Hongwei, LI Yanhong
    2004, 23 (5):  33-42.  doi: 10.11820/dlkxjz.2004.05.005
    Abstract ( )   PDF (1470KB) ( )   Save

    As a typical resource-rich city (developed on the resources of petroleum, pasture land and cultivated land), Daqing City of Heilongjiang Province is one of the regions where the relation between human and land acts the most intensively, and also is the region where the land utilization changes sharply and possesses particular characteristics. It is especially important to the environment improvement, adjustment of industry structure in resource-rich cities and realization of sustainable development of resource-rich cities to reveal the time and space change characteristics and their change laws of land utilization in this area and to discuss the safety problems caused by land utilization change. Therefore, this study is based on MSS and TM image during five periods in 1978,1988,1992,1996 and 2001, obtaining land utilization information in different periods of 20a. This study uses GIS technology as the data integration analysis platform and calculates the index of wetland landscape pattern and the process of time and space shifting of each wetland landscape type for the purpose to describe from the point of view of landscape pattern quantitively the response of wetland landscape process to the land utilization change and the threaten of wetland ecology safety herefrom. The result shows that important reasons causing the reduction of wetland include the continuous increment of cultivated land, enlargement of land for building and the process of wetland salination and wetland becoming meadow. The land utilization causes division, breaking and rapid reduction of wetland landscape, forming a threat to the safety of biology variety, water resource and human health. Thus we should carry out analysis, evaluation, planning and design of different wetland according to the principle of symbiosis of human beings and nature, and gradually recover the original natural wetland landscape in order to let it exert full wetland functions.

    References | Related Articles | Metrics
    The Preliminarily Study on the Ecological Environment Effects of Land-use Change in Red Earth Hilly Area in Southeast China
    YANG Fengting, LIU Jiyuan, ZHUANG Dafang, HU Yunfeng
    2004, 23 (5):  43-55.  doi: 10.11820/dlkxjz.2004.05.006
    Abstract ( )   PDF (2062KB) ( )   Save

    In recent years, ecological environment problems caused by unreasonable land use become more and more serious, and the ecological environment effects of land use arouse general concerns. Benefiting from southeast monsoon, red earth hilly area in China has excellent water and heat conditions, and land use here changes rapidly these years. Unreasonable land use, however, results in serious land degradation, which reduces the land productivity. Furthermore, it has deep impacts on water resource and global carbon cycle. So studies on the ecological environment effects of land use in this area are not only important to the sustainable development of agriculture, but also helpful in understanding the role of this area playing in global changes. In this paper, we summarize the development and fruits of related researches, and find that most of the researches focus on land degradation and its ecological restoration, which has close relation with land productivity, while researches on the impacts of land use on global carbon cycle are seldom. In addition, there’s a lack of uniform indexes for evaluating soil quality, and the evaluating methods to integrate soil properties with soil management practices are also short. Finally, studies we should pay more attention to are pointed out.

    References | Related Articles | Metrics
    A Review on the Research of World Cities
    XIE Shouhong, NING Yuemin
    2004, 23 (5):  56-66.  doi: 10.11820/dlkxjz.2004.05.007
    Abstract ( )   PDF (1648KB) ( )   Save

    On the condition of globalization world, cities have uprised and global urban hierarchy has formed, and this is a remarkable phenomenon in current economic and urban development. Study on world city has been emphasized by both foreign and domestic researchers since 1980s. In this article the authors firstly divide the process of research on world city into three phases, including the early research phase (before the 1980s), the world city theory formation phase(in the 1980s, the main sign is the publication of Friedmann’s World City Hypothesis)and the world city theory development phase (from the 1990s to the present). Meantime, the authors also conclude the main present schools and trends of the world city research as follows: 1) Sassen’s global city hypothesis; (2) the Los Angeles school, including scholars such as Scott, Soja, Davis, Jameson et al; (3) the study on the information technology revolution and world city development by Castells, Batten,Warf, Hepworth, Lanvin et al; (4)the study on world city network mutual function by Taylor, Walker, Catalano, Hoyler et al; (5) the study on the world city of developing country and area. Then, the paper in detail introduces and explains the main ideas of overseas scholars research on world city’s concept, functions, classifications, formation mechanism, world city network mutual function et al. At last, the authors simply analyze Chinese scholars’ research process and present situation on world city and some thought of constructing world city in China.

    References | Related Articles | Metrics
    Study on Ecological Landscape and its Integration With the City Form
    CHEN Shuang, WANG Jin, C.Y. Jim
    2004, 23 (5):  67-77.  doi: 10.11820/dlkxjz.2004.05.008
    Abstract ( )   PDF (1784KB) ( )   Save

    Since the end of 1800s ecology has been used in study on urban spatial structure. Within recent 20 years, the primary principles of landscape ecology have been frequently adopted in research on layout of natural open spaces in cities. This paper discussed definition and establishment of ecological landscape; with a case of Nanjing in China, analyzed the sustainability of city form, explored the method of coordination of the natural and semi-natural landscape with the artificial building blocks in highly developed cities,and presented a pattern by which the ecological landscape was integrated with the city form. Its major content could be described as: integration of green wedges with star city form at the metropolis scale, integration of greenway networks with road networks at the main city scale and integration of green corridors with neighborhoods at the street block scale. The case study may provide suggestions for ecological landscape restoration and for ecological security pattern establishment in urban areas.

    References | Related Articles | Metrics
    Statistical Analysis on the Relationship between Road Network and Ecosystem Fragmentation in China
    LI Shuangcheng, XU Yueqing, ZHOU Qiaofu, WANG Lei
    2004, 23 (5):  78-85.  doi: 10.11820/dlkxjz.2004.05.009
    Abstract ( )   PDF (889KB) ( )   Save

    Road construction has important impacts on ecosystem and landscape fragmentation and it is significant to investigate the fragmentation characteristics for management of road and its surrounding ecosystem. Based on the road network of China, the relationship between road network at different levels and ecosystem fragmentation is analyzed using GIS and FragStat software in this paper. The results show that the ecosystem areas influenced by road network account for 18.37% of the total country area. Among the areas affected by road network at different levels, the area affected by countryside road is maximal, with 161.76×104 km2; the following is the area affected by second level road network, with 5.86×104 km2; and the areas affected by freeway and the third level road network are 4.59×104 km2 and 2.27×104km2,respectively. The area affected by the fourth level road network is minimal, with 0.39×104 km2. The ratios of agricultural area affected by freeway and the first level road network are the largest, with above 70%.The lower the road network level, the less the ratio of agricultural area affected by corresponding road network. For forest and grass land, the lower the road network level, the larger the ratio of agricultural area affected by corresponding road network. While for wasteland and water area, there is no distinct difference among the areas affected by different road network. The total number of patches increases and the average patch area decreases with the decrease of road network level and the increase of amount of road network, which shows that the ecosystem fragmentation degree rises. Meanwhile, the mean patch fractal dimension increases obviously, which shows that the complexity of patch shape rises.

    References | Related Articles | Metrics
    A Study on Location Choice Decision of Urban Residents Using Ordered Logit Model
    ZHENG Siqi, FU Yuming, LIU Hongyu
    2004, 23 (5):  86-93.  doi: 10.11820/dlkxjz.2004.05.010
    Abstract ( )   PDF (994KB) ( )   Save

    With rapid growth of housing market in urban China, urban residents have more freedom in location choice, which also demonstrates many new characteristics. Based on the data from a special designed survey of location choice in five large cities of Beijing, Shanghai, Guangzhou, Wuhan and Chongqing, this paper empirically analyzes the location choice behavior of urban residents and the influencing factors using the ordered logit model. The factors influencing location choice can be divided into two groups: household level variables and city level variables. The former group includes income, employment location and preference of environment; and the latter group comprises housing price, suburbanization process and the infrastructure construction in the suburb. The empirical results show that these variables are all significant in the ordered logit model and consistent with theoretical analysis. Higher-income people still prefer to the locations nearer to the city center, and the immature state of infrastructure construction and service in suburb constrains the suburbanization process in Chinese cities. These empirical findings have important implications for policy-makers and developers.

    References | Related Articles | Metrics
    The Advance of Urban Wetland Study
    SUN Guangyou, WANG Haixia, YU Shaopeng
    2004, 23 (5):  94-100.  doi: 10.11820/dlkxjz.2004.05.011
    Abstract ( )   PDF (913KB) ( )   Save

    In this paper, the definition of urban wetlands was given based on analyses of the existence and connotation of urban wetlands. Urban wetlands are defined as those kinds of natural and artificial wetlands that distribute in urban areas and compose the ecoenvironmental foundation of cities. Chief directions and advances of urban wetlands studies at home and abroad were summarized, the differences of urban wetlands studies between China and other countries were analyzed, the main domains and existing problems of urban wetlands studies were pointed out, and the subject frame of urban wetlands science was constructed primarily. A basic definition of urban wetlands science was proposed in this paper as the science which studies the distribution, type, function, evoluation and management of urban wetlands. The studies would have positive significance to the development of wetland science.

    References | Related Articles | Metrics
    Impact of Tourist Activities on the Environment in Bitahai Lake Wetland Ecotourism Scenic Spot
    WANG Jinliang, WANG Ping, LU Fen, YANG Guihua
    2004, 23 (5):  101-108.  doi: 10.11820/dlkxjz.2004.05.012
    Abstract ( )   PDF (1246KB) ( )   Save

    Bitahai lake wetland could incarnate the artistic conception of “Shangri-La” in farthest. It attracts many tourists to visit every year. It is the most important spot of “Shangri-La” ecotourism scenic region. Based on field investigation and analysis, the paper analyzed the temporal and spatial distribution of tourist’s activities and their impacts on environment factors (soils and plants, etc.). The results showed that the closer to tour routes and the longer the tourist’s activities last, the stronger the impacts of tourists’ activities on the soils characteristics and plants characteristics are. In the same plot, the changes of soil characteristic are quite different under different types and intensity of stresses. The impacts of tourist’s activities on vegetations include: vegetation removed, trample of horses and tourists, collection of tourists, nibble of horses, garbage thrown away by people, excrement of horses, and invasion of species. The negative impacts of tourism activities on environment would result in the loss of wetland landscape, biodiversity and ecotourism. Then, some measures on environmental protection of Bitahai lake wetland were represented in the article.

    References | Related Articles | Metrics
Share: