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  • 2005 Volume 25 Issue 5
    Published: 20 September 2005
      
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  • Regional Patterns Changes of Chinese Grain Production and Response of Commodity Grain Base in Northeast China
    CHENG Ye-Qing, ZHANG Ping-Yu
    2005, 25(5): 513-520. https://doi.org/10.13249/j.cnki.sgs.2005.05.513
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    Grain security is one of the severe challenges to the world,especially to China in 21 century.According to statistical materials and investigation data in recent 10a,regional pattern changes of grain production in China was discussed with the methods of regional difference analysis,such as concentration index,absolute different index and relative different index.The study showed that China’s grain production kept increasing as a whole,and the annual average ratio was about 3.43%.With the change of agricultural production condition,technology,macro-economic circumstance,market condition and land use,main gain production centers have been moving from the south to the north and from the east to the central in the last decade,so that the north and central areas become new grain production centers for the future China.Also,the difference of regional change was very evident,the biggest difference emerged between the north and south China,but the differences among provinces and the eight main production regions were not considerable.The Northeast China is one of strategic bases for national grain security,where the amount and proposition of commodity grain are both in the leading place among regions.However,grain production in this region is not stable and represented considerable fluctuation periodically,which was caused by environmental degeneration,serious natural disaster,onefold agricultural structure and farmer’s unwillingness to promote grain production.Corresponding to the nationwide shifts in grain production,the construction of commodity grain bases in Northeast China becomes a strategic policy for the national grain security.Key countermeasures are to improve agricultural ecological environment,to adjust agricultural structure,and to optimize distribution of special commodity grain bases etc.
  • Identification of Industrial Clusters—A Case Study of Beijing Manufacturing Industries
    HE Can-Fei, LIANG Jin-She, ZHANG Hua
    2005, 25(5): 521-528. https://doi.org/10.13249/j.cnki.sgs.2005.05.521
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    Recently, industrial cluster has been a hot focus in economics, management and geography. Regional and industrial policies are also oriented towards the promotion of industrial clusters. The identification of local clusters, however, is still poorly established. Qualitative methods of identifying industrial clusters, such as Industry Perception Method, rely heavily on the experts' subjective judgments and lack strict rules to make decisions, therefore confine to a number of limitation. For example, the regionally dominant firms may mislead the researchers' judgments. The cross-sectional comparison of industrial clusters in different regions could be difficult. This paper demonstrates that industrial clusters can be recognized using principle component analysis (PCA). Based upon a correlation matrix, which is derived from the input-output table and measures backward and forward industrial linkages, this paper applies PCA to identifing industrial clusters. Several indices are further developed to evaluate PCA's performance in identifying regional industrial clusters. Correlation analysis is then applied to testing the spatial agglomeration of related industries. Taking Beijing as a case, this paper identifies 14 industrial clusters based on the 1997 inputing output table. Industrial clusters are formed around smelting and pressing in ferrous metals, chemicals, electronics, textiles and car production etc. Industries in those clusters are strongly tied with each other through sale-purchase linkages, and agglomerate in similar locales.
  • Trans-provincical Regional Governance: New Idea on Economic Conformity for Trans-province Metropolitan Circle of China
    TAO Xi-Dong
    2005, 25(5): 529-536. https://doi.org/10.13249/j.cnki.sgs.2005.05.529
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    With the development of economic globalization, some trans-province metropolitan circles such as Yangtze River Delta, Jingjintang, Pearl River Delta,have become the most important spatial unit of China regional economy development. Today, how to deal with the relationship between administrative region and economic region, and to achieve trans-province metropolitan circle' spatial conformity, are the focuses of government and academic research. Based on the discrimination of four concepts of city cluster, metropolitan district, metropolitan circle and metropolitan belt,the article puts forward concept of trans-province metropolitan circle and its six basic mature conditions. Through the theory of 'administrative region's economy', the paper considers system of administrative region's division and government management is the bottleneck of trans-province metropolitan circle conformity under present system. Finally, based on the governance theory, it puts forward a new conformity thought —'trans-province region governance’and builds up a basic system of trans-province regional governance, which including: ①modern region's governance system of member governments of trans-province metropolitan circle;②modern political region system of trans-province metropolitan circle;③modern region's market system of trans-province metropolitan circle;④modern region society system of trans-province metropolitan circle;⑤modern inter-city cooperation system of trans-province metropolitan circle.
  • Characteristics of External Function of Producer Services of Regional Centers: Case of Guangzhou, China
    YAN Xiao-Pei, ZHONG Yun
    2005, 25(5): 537-543. https://doi.org/10.13249/j.cnki.sgs.2005.05.537
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    Guangzhou is the central city of one of the developed regions, Pearl River Delta (PRD), in China. The level of producer services in Guangzhou is better than most of the other cities in China. To study the characteristics of the external function of the producer services in this central city will be helpful to understand the current level of producer services in China. According to the literature review, a conclusion was drawn that producer services have the function of the basic activities. After analyzing the statistical data, this paper proves that the producer services of Guangzhou have the same function. In order to find out the characteristics of the external function at present, a face-to-face survey to the producer services organizations that located in Guangzhou was done. The spatial scale of the market, the type of the clients and the distribution of the services are focused in the survey. There are five findings. ①Though the share is low, PRD is the biggest part in the external market of the producer services of Guangzhou. ②The share of external market declining with the distance, means that the farther away from Guangzhou, the lower the market share of the producer services from Guangzhou. ③The clients involve the primary industry, the secondary industry and the tertiary industry, and the tertiary industry consumes the most part of the producer services. ④There is gap between the share of the distribution of the clients and the services, which means that in one market area, the market share for the clients is different to that for the producer services. It shows that the insufficiency of the market exploration by the producer services organization in Guangzhou, though the spatial scale of the external market of it is extensive. ⑤PRD and Guangdong Province, the two nearest markets to Guangzhou, will be the most dominating areas for the producer services organization of Guangzhou to exploit in the coming three years. And another survey to the manufacture companies in PRD was done. The findings explain why the effect of the producer services in Guangzhou is so limited to the manufacture in the PRD currently.
  • Study of Geographical Foundation and Difference Factor on Regional Development of Changshan Islands
    LUAN Wei-Xin, WANG Hai-Zhuang
    2005, 25(5): 544-550. https://doi.org/10.13249/j.cnki.sgs.2005.05.544
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    This paper takes Changshan Islands region in Dalian City of Liaoning Province as study object.The authors make a concrete analysis on the archipelago of regional differences in four respects,i.e.the comparing of land and sea area in island region,the constitutional characteristics of island ecosystem,the feasibility of infrastructures sharing and the competitive power of industries in archipelago region.In this paper,we analyzed more concretely the differences from economic development level,population distribution,marine aquaculture,maritime transportation and finance investment among all island villages and towns of the archipelago region.We think,①The technological progress is a precondition of improving regional development environment of islands;②The policy is an important influeoce factor to form the differences among the islands;③The impact on archipelago area of natural resources is still very obvious;④The impact on island of location condition is being enlarged.The result of study not merely has important practice meanings to guide the regional development of Changshan Islands,and this paper seeks to apply regional development theories to studying special area like archipelago at the same time.
  • Eco-environmental Problems and Livestock Farming and Agricultural Development in High Cold Minority Area: A Case Study of Gannan Tibet Autonomous Prefecture
    LI Zhi-Gang, DUAN Huan-E
    2005, 25(5): 551-555. https://doi.org/10.13249/j.cnki.sgs.2005.05.551
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    Gannan Tibet autonomous prefecture is situated in the southwest part of Gansu Province and the transition zone among Tibet Plateau, Loess plateau and west Qinling Mountains, where the average altitude is 3 000 m. It has an area of 45,000 km2 and a population of 670,000. The area is an important water resources conserving area and an ecological protective screen area in upper reaches of Yangtze and Yellow rivers. However, there are many serious eco-environmental problems in this area at the present time: the fearful degeneration, desertification and salinization of grasslands, the tremendous forest destruction by human hag, and subsequent low forest coverage, the obvious shortage of water resources, the quick decrease of bio-diversity, and the increasing water and soil erosion. All of these are caused by both natural and human factors. Facing above problems, it is necessary for sustainable developmental strategy and eco-economic idea to be established in human economic activity of the area so as to combine ecological efficiency organically with economic efficiency, and to search for a rational resources utilization ways and a locality livestock farming and agriculture development model which would well adapt to local ecological laws. Thus the corresponding countermeasures to this area are suggested as follows: (1) controlling eco-environments by laying stress on managing the degeneration, desertification and salinization of grasslands, and implementing enclosure treatment and rotational grazing in pasturing region; (2) utilizing the local forage and grass resources reasonably by building and collocating some livestock fattening bases; (3) innovating the institution of grassland use and livestock farming management by advancing grassland circulation through the forms of subcontract, rent, sublet, exchange and co-management, promoting grassland and livestock to be transferred to people or groups who well understand the livestock farming technology and management method, enlarging livestock farming management scale, and founding an effectual ecological construction mechanism; (4) enhancing the scientific and technological contents for eco-environmental construction and livestock farming and agriculture development by developing and introducing some applicable technology such as selection and breeding of superior species for livestock, control of rodent damage and insect pest, and the grass-crop rotation system in soil and water loss region. (5) adjusting traditional territorial structure of agriculture and optimizing land use form according to spatial ecology differentiation regularity; (6) exploiting superiors resources to develop special livestock farming and agriculture, pushing forward the process of rural urbanization and the industrialization for livestock farming and agriculture.
  • Systemization and Control of Point-axis Layered Industrial Spatial Structure in Changchun Metropolitan Area
    CAO Chuan-Xin, ZHANG Quan, LI Cheng-Gu
    2005, 25(5): 556-560. https://doi.org/10.13249/j.cnki.sgs.2005.05.556
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    By analyzing and diagnosing the resource supporting system of the forming and developing of Changchun metropolitan area, systematically scrutinized the point-axis layered spatial structure of the first industry, the second industry and the third industry in the area, scientifically advanced detailed strategy and orientation for systemization and control.
  • Precipitation and Temperature Probability Characteristics in Climatic and Ecological Transition Zone of Northeast China in Recent 50 Years
    ZHANG Yao-Cun, ZHANG Lu-Jun
    2005, 25(5): 561-566. https://doi.org/10.13249/j.cnki.sgs.2005.05.561
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    Changes in the occurrence frequency, strength and location of the extreme weather and climate events will occur with global warming. It is of interest to study if the frequent occurrence of extreme weather and climate events is related to change of the climatic background. In this paper, the winter and summer precipitation and temperature data in the climatic and ecological transition zone of Northeast China are used to investigate the interannual variation and probability distribution characteristics of precipitation and temperature in recent 50 years. Results show that there exist significant interdecadal variations in winter and summer precipitation and temperature, and the probability distribution characteristics are different in different periods. The probability distribution differences are probably related to the frequent occurrence of extreme weather and climate events such as high temperature, drought, flooding in recent years. Since the 1980's, precipitation has been in the probability distribution of low ensemble average, and temperature in the probability distribution of high ensemble average. Thus, occurrence probabilities of warm-dry winter and hot-drought summer will increase in the climatic and ecological transition zone of Northeast China.
  • Spatial Differences of Precipitation over Northwest China During the Last 44 Years and Its Response to Global Warming
    JIN Li-Ya, FU Jiao-Lan, CHEN Fa-Hu
    2005, 25(5): 567-572. https://doi.org/10.13249/j.cnki.sgs.2005.05.567
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    Based on climatic data of precipitation and temperature of 77 meteorological stations covering 1958-2001 in the northwestern China (the area is within the north of 35癗 and west of 105癊 in China) as well as the NCAR/NCEP reanalyzed data, and by using the methods of regressive analysis and composition analysis, the inter-annual variation of the precipitation over the northwestern China as well as its relationship with global warming were studied. The results show that there exists relationship between the anomalies of precipitation over the northwestern China and that of the global mean temperature. However, the trends of precipitation with temperature are different in west (west of 93癊) and east part (east of 93癊) of the northwestern China. In west part the precipitation has increased with global warming in the past 44 years, while in east part the precipitation declined.
  • Evaluation of Eco-environmental Stability in Tibet
    ZHONG Cheng, HE Zong-Yi, LIU Shu-Zhen
    2005, 25(5): 573-578. https://doi.org/10.13249/j.cnki.sgs.2005.05.573
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    By making a evaluation index system and using AHP to determine the evaluation factor's weights, this paper builds the valuation model of eco-environmental stability of Tibet and uses the overlay function of raster-GIS to make a result map, and finds the distribution characteristics of eco-environmental stability of Tibet based on the analysis of result map. The study shows that the eco-environmental stability of Tibet is almost good and the unstable area that is only 9.78% of the total area of Tibet is distributed in the middle and low reaches of the Yarlung Zangbo river. To protect the eco-environmental of the unstable area from farther degenerating, the government should pay more attention on the eco-environmental construction work on this area.
  • Land Quality Evaluation Indicators at County Scale Based on "Press-State-Response" Framework
    GUO Xu-Dong, QIU Yang, LIAN Gang, WANG Jing
    2005, 25(5): 579-583. https://doi.org/10.13249/j.cnki.sgs.2005.05.579
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    Huge press to land resources with economic development and land quality degradation and ecological environment deterioration urge to build up the land quality indicators based on"press-state-response" framework, which can reflect distinctly the reasons and results of land quality changes and correspondingly adoptable strategies. By taking Ansai County, Shaanxi Province, in the northern China as an example, land quality indicators based on "press-state-response" framework for soil degradation by water erosion were built up. Press indicators include topography, farmland, population, income and spatial pattern indicators. State indicators include soil erosion, soil fertility and crop yield. Response indicators include land use and policy. The values of land quality indicators were got by the application of GIS, model simulating and statistical analysis. Based on land use map of Ansai County in 1998, the values of press, state and response were got respectively by giving values to different grades of indicators and computing the average. The results showed the press to land in Ansai County came mainly from topography and disturbance of human activities. The land whose slope is more than 25皁ccupied about 47.11% of total land area, while the land of slope less than 5癷s only 4.59%. The proportion of farmland and crop seeding area to whole area is respectively 52.48% and 47.96%,the proportion of cultivation income is also higher, which indicated higher dependence of farmers on land. The average soil erosion is estimated about 6268t/km2 by using USLE model. The soil fertility and crop yield is low, so the state of land quality is also low. Response of Land quality is not active, the evaluation value is only 1.75. This paper also discussed the applicability of indicators in land quality management practice and proposed it is probably one of the most important trend for land quality research to build up the land quality indicators and methods system based on PSR framework, which is supported by "3S"technology combined with field investigation and relative basic geographical information.
  • Spatial Sampling Methods and Their Applications in landscape pattern analysis for landscape ecological research
    GUO Jin-Ping, ZHANG Yun-Xiang
    2005, 25(5): 584-589. https://doi.org/10.13249/j.cnki.sgs.2005.05.584
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    Because of the comprehensive effects of multiple environmental factors to landscape pattern and ecological processes, mathematical methods are more eagerly needed in landscape ecological researches to explore the general distribution pattern of landscape elements in highly heterogeneous and changing landscape. A great challenge to improve the mathematical landscape pattern analysis is providing a satisfied spatial sampling method. Many quantitative landscape analysis methods cannot be used because lacking of a moderate spatial sampling method. This paper introduces two spatial sampling methods proposed and used in Guandishan forest landscape ecological research. They are Uniform-Grid-Square sampling method and Uniform-Grid-Point sampling method. These sampling methods used to provide data for landscape pattern analysis. The quantification method of sample-square is respectively proposed in the paper. As examples, the usage process of two spatial sampling methods in landscape trend-surface-analysis, landscape element spatial correlation analysis, landscape element dominantness analysis, analysis of landscape element spatial distribution pattern, and landscape dynamic modeling are introduced respectively. Based on the examples, availability of the methods is demonstrated, and the potential usages in other spatial analyses are also prospected.
  • Grain-size Characteristics and Their Environmental Significance of Hongze Lake Sediments
    HE Hua-Chun, DING Hai-Yan, ZHANG Zhen-Ke, SHI Xiao-Dong, LI Shu-Heng, MAO Long-Jiang
    2005, 25(5): 590-596. https://doi.org/10.13249/j.cnki.sgs.2005.05.590
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    As a main lodging of surface substances, lake sediments continuously and sensitively record information of regional climate and environment with annual to decadal resolution. The sediment core of HLC with a length of 112 cm was taken from deep water location in Hongze Lake in 2003,the sediment were cut at interval of 2 cm and were measured for grain sizes by the particle-size analyzer "Mastersizer 2000"made in England. Based on accurate dating by 210Pb,the authors reconstruct the dry-humid transformation history of the regional climate according to the vertical profile of sediment particle sizes, which provides a new effective way for recovering the century-scale climatic changes, the following conclusions are drawn: (1) By the analyses of the grain-size parameters of the Hongze lake sediments, three stages of environmental changes since 300 years ago have been distinguished. They are:Ca.1720-1795A.D., the amount of rainfall was less and weather was drought; Ca. 1795A.D.-1890A.D., as a whole, the average grain-size was decrease, the weather was drought in this stage but Ca.1886 A. D. the flux of water into Hongze Lake was increased; Ca.1890 to current, the changes of grain-size parameter was acute and frequent and this changing phenomenon perhaps instead of the environment fluctuate in shorter periods. (2) During long time-scale studies, lake level is the most important factor domination sediment grain size. Sediments are finer during the humid period of high water level because coarse particles cannot be transported to the lake's deep-water part. On the contrary, during short time-scale studies within a given climate period, rainfall change becomes the key factor determining sediment grain size because the level is basically constant. When rainfall is heavy, runoff flow is strong enough to bring coarse terrestrial particles to the sampling location, resulting in large grain sizes. (3) Grain-size parameters changes is relate not only with the natural environment changes but also with the human activities such as Huanghe(Yellow) River changing channel and some brakes were built up around the lake.
  • Grain Size Characteristic of Sand-dust Sedimentary in Harbin City and Its Implication
    HE Kui, XIE Yuan-Yun, ZHANG Li-Juan, ZHOU Jia, KANG Chun-Guo
    2005, 25(5): 597-600. https://doi.org/10.13249/j.cnki.sgs.2005.05.597
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    The collection and grain size analysis were carried out for sand dust sedimentation in Harbin, 20th March 2002. The result indicated that sand dust sedimentation gave priority to silt (4~8Φ), occupying 71.18%, sand composition (>4Φ) is 21.7% and clay composition (<8Φ)only 7.13% at Harbin. The granularity of sand dust sedimentation was the coarsest in the reports so far. The sedimentation granularity distribution was charactered by multi-peak states, coars sand silt of 4.85-5.10Φ grain grade composed first main peak, occupying about 7.4%, medium sand of 1-1.25Φ grain grade composed second main peak, occupying about 1,29%,and clay composition of 10.25-10.5Φ grain grade composed third main peak, occupying about 0.52%. The average grain diameters of sedimentation (Mz) was 5.14Φ, sorting coefficient, 1.81, Skewness, 0.044, and Kurtosis, 1.494, silt and clay ratios, 7.3. The granularity features shown that sand-dust sedimentation was admixture, derived from different sources both far distance and short distance, and coarse particle was near-sources material that was transmitted by low altitude airflow. The biology status and zoology environment of sand-dust sedimentation source area are relatively inclement. Nudity infield, wasteland and plain, river bed and floodplain fine alluvium, bareness lakes and dust of city earths surface and construction sites, and so on, may be material fountainhead. The keystone of weather projects for preventing sand-dust in Harbin should put to controlling sand-dust fountainhead around Harbin.
  • Study on the Characteristics of Blown Sand-dust on the Surface of Different Land Use Type in Beijing Outskirts
    WANG Sheng-Tang, ZHAO Yan-Zhi, ZOU Xue-Yong
    2005, 25(5): 601-605. https://doi.org/10.13249/j.cnki.sgs.2005.05.601
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    Sand-dust weather can be divided into dust storm, sand blowing and dust haze. The sources of sand-dust during sand blowing weather mainly come from Beijing outskirts. For effectively combating sand blowing in Beijing region, we have finished a series of field observations of sand blowing on different utilizing land types in Beijing outskirts during the spring of 2003 and 2004. At the same time, soil samples of each type of land were collected, and the samples were analyzed in the lab later. The primary conclusion is that wind velocity to blow sand on bare land surface in Beijing outskirts is about 6m/s, and the characteristics of sand blowing are quite different to each land using type. Under the condition of the same wind velocity, sand blowing intensity of each type of land in the order of degree is ploughed land, land with crop residue, orchard land, unused land, forest land and grassland. Different land use types have different sand blowing properties, which indicates that adjusting land use structure is an important method to control sand blowing in Beijing.
  • Changes of Soil Ecosystem in Karst Mountain Areas Under the Impact of Different Vegetations
    LI Yang-Bing, GAO Ming, Shao Jing-An, XIE De-Ti, Wei Chao-Fu
    2005, 25(5): 606-613. https://doi.org/10.13249/j.cnki.sgs.2005.05.606
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    In this study some typical karst mountainous regions in Chongqing were selected to discuss the essential characteristics of soil degradation during vegetation change processes. The results showed that: (1) After the vegetation turned into secondary vegetation or man-made vegetation, or reclamation, soils would be degraded in physical properties in the karst mountainous environment. Compared with the abandoned field, shrub-grassland, secondary forest and natural forest, in the surface soil layer of sloping cropland, the contents of >2 mm-sized water-stable aggregates dropped obviously to 52.1%, 24.7%, 29.9%, 22.8%, and those of 1mm-to 0.05 mm-sized particles increased, but those of 0.05mm-to 0.001mm-sized particles decreased, demonstrating apparent sandification; in slopping cropland soils, the capillary and aeration porosities, long-term soil water-retention and water-supplying capacities and soil resistance against drought were reduced as well, and their field water-holding capacity accounts for 79.3% of that of the forest land soils. (2) The contents of soil organic matter and total nitrogen are controlled completely by vegetation type and land-use intensity. The contents of SOM (soil organic matter) in sloping cropland are lower than in woodland and grassland. After the land was converted for forest and pasture, the contents of SOM would increase steadily, though this trend of increasing is rather slow in the early days when over-reclamation is stopped and the land is converted for forest and pasture. The contents of SOM in man-made woodland and secondary forestland are still lower than in natural forestland. (3) Herbaceous species increase and woody plants species decrease with increasing land use intensity, therefore, the soil seed banks degrade more seriously. With the process of evolution from abandoned field, shrub-grassland to secondary forestland, the ecological dominance will be reduced and the Richness index and diversity index will increase in soil seed banks. Based on the above research results, it is suggested that land degradation in the karst ecosystem is essentially characterized by the degradation of soil functions that are served as water banks, nutrient banks and soil seed banks, and the degradation rates of these three banks are different.
  • Impacts of Human Beings' Activities on North Jiangsu Tidal Flat
    WU Xiao-Gen, WANG Ai-Jun
    2005, 25(5): 614-620. https://doi.org/10.13249/j.cnki.sgs.2005.05.614
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    Tidal flat in North Jiangsu Province is very extensive, where human beings take activities strongly and frequently in history. With the incrising of exploisive intensity of tidal flat in North Jiangsu Province, the impacts of human beings' activities on tidal flat evolution are more markable. The natural equilibrium shape of tidal flat section is protruding, but the section will be adjused because of the changing of equilibrium relationship between water and sediments after tidal flat reclamated and sea wall built, and tidal creek near the sea wall accumulated. The ecosystem structure on tidal flat changed after introducing plant such as Spartina anglica, Spartina alterniflora. Beacuase plant decreases current speed and weakens wave energy, the plant plays the role of catching sediments. These impacts increase the accretion rates on tidal flat and change the zonable structure on tidal flat, moreover, the shape of tidal creek in inter-tidal flat changed because of the existence of plant. Besides, the sediment transportation direction would be changed after port engineering built.
  • Advantages and Disvantages Analysis of Dam Construction and Eco-environment Protection
    MA Xiao-Fan, GUO Xiao-Ze, WANG-Ju, HAN Zhen-Yu, YU Lian-Sheng
    2005, 25(5): 621-625. https://doi.org/10.13249/j.cnki.sgs.2005.05.621
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    Recently the attitude to dam has significant been changed, man never pursues the short-term benefit of dam but pays more attention to the ecological problem caused by dam project. Aiming at the current understandings towards the social and environment problems caused by the dam construction in the worldwide and the external fact that the policies for dam have been changed in many nations, this article analyzes the status of dam constructing, presents the concept model of advantages and disadvantages relations between the water conservancy resources developing and eco-environment protection, establishes an advantages and disadvantages relation index model for the dam construction project(α=√|A|2+|B|2/EC) and the coefficient model for compensation advantages and disadvantages(P=√|EC|2+|A|2/EC), demonstrates the feasibility of the dam construction according to the analysis of advantages and disadvantages of dam projects. When disadvantages excess advantages, the dam isn't feasible. The compensation of loss what the dam produces must be added in order to maintain the feasibility of dam that is to say to turn its exterior cost into its interior cost. The ration method is dynamic and it essentially embodies the sustainable development. This article selects a certain dam for instance to analyze the advantage and disadvantages relation. The result is disadvantages excess advantages and 8.55623 billion yuan must be compensated in order to maintain the feasibility of the dam construction. At last, this article points out that the opposite relation between developing and protecting could transform according to the sufficient compensation for the eco-environment loss in dam construction.
  • Characteristic of High and Low Water Resources Change in Jinhua City
    FENG Li-Hua, ZHANG Xing-Cai, SANG Guang-Shu, WANG Min, ZHOU Jiang
    2005, 25(5): 626-630. https://doi.org/10.13249/j.cnki.sgs.2005.05.626
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    In order to gain reliable and complete precipitation serials, textual research is made to local records such as Jinhua Official Records and Quzhou Official Records respectively, then based on the precipitation data at Jinhua Station from May to September during 1980-2003, protracted the precipitation year at Jinhua Station to 2003. Based on the analysis of the historical and measured data in 1470-2003, the characteristics of high and low water resources change in Jinhua City can be achieved as follows: (1) The 17th century is the frequent period with high and low water resources change in Jinhua City, 1642-1671 of them is the most concentrated time of high and low water years, and there is the special high and low water years of 16 times in 30 years. (2) The greater the high and low water resources change, the shorter the sustained years, the fewer the times it appears. There is 8 years in the medium water year of the longest sustained time (in 1893-1900). (3) There are varied cycles of high and low water resources change, and the cycle change of 20-22 years is very clear. The curve of high and low water change has descended to the lowest point currently and started rising gradually, therefore within the future 20 years, it will keep on rising, namely turning from high water predominated stage to low water predominated stage. (4) The high and low water change responds evidently to sunspot activity and El Nino event. The anomalous annual precipitation of 3 years average at Jinhua Station around the transformation year of the magnetic cycle is all positive. The years of annual precipitation R>1550 mm at Jinhua Station mainly appear in the same or next year of El Nino. (5) The May-September precipitation occurring once 5 years in low water year in Jinhua City is only 604 mm and that occurring once 10 years is only 550 mm.
  • Unascertained Risk Analysis of Groundwater Level Drop
    LI Ru-Zhong, QIAN Jia-Zhong
    2005, 25(5): 631-635. https://doi.org/10.13249/j.cnki.sgs.2005.05.631
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    As one of the important environmental elements, groundwater is a kind of valuable natural resources. With the development of social economics, the requirement for groundwater is more larger than ever in the cities of the northern China. Because of drop of groundwater level arised from the excessive exploitation, the groundwater quality is faced to be polluted. Therefore, how to determine the drop value of groundwater level scientifically is of importance for the protection of groundwater quality. In practice, the drop value is often calculated using a certain model, which neglects the uncertain characteristics of hydrogeological parameters. In fact, as many other things, the groundwater resources system is also a system with the characteristic of unascertainty. On the basis of defining unascertained parameters of hydrogeology, an unascertained model for forecasting drop value of groundwater level is established in the paper. According to the model, not only the probable drop value interval of groundwater level but also its corresponding distribution of faith degree can be obtained. The study result shows that these models proposed above are suitable for risk assessment of groundwater level drop, and the research achievements also overcome the defects of traditional evaluation method effectively. In order to reflect the probability of drop value of groundwater level exceeding a certain standard, an unascertained event is defined. On the basis, a model for calculating the faith degree what the unascertained event happens is provided.
  • On the Catastrophabilities of Urban Geomorphic Environment of Shanghai
    DAI Xue-Rong, SHI Yu-Xin, YU Li-Zhong, LI Liang-Jie, HE Xiao-Qin
    2005, 25(5): 636-640. https://doi.org/10.13249/j.cnki.sgs.2005.05.636
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    With the rapid development of urbanization and re-urbanization, the urban geomorphic environment (UGE) of Shanghai has ever been featured with obvious catastrophabilities. The latest disastrous and representative case is the water-seeping incident happened on July 1st 2003 in constructing the No.4 metro line (underground), which has caused a huge economic loss of 150×106 Yuan (RMB). In deed, this incident includes three continuous catastrophic stages—water seeping, land collapse and local flooding. It implies that the Shanghai's UGE has become sensitive, fragile, and therefore catastrophic under conditions of high pressure of human activities. Viewing from the geomorphic materials, geomorphic forms and geomorphic processes respectively, this paper discusses the catastrophabilities of UGE in Shanghai proper in relation to man-land interaction. From the geomorphic materials, the most catastrophic factor is the wide spread water-bearing sand-to-silt layers formed in different ages in Quaternary, which may cause water-seeping incidents under conditions of frequent engineering activities. They are well developed in this area and exist in different depths within the extent of the activities. From the geomorphic forms, Shanghai is an extremely flat land with low elevation as just emerged from the sea (the Yangtze delta). Since 1921 the central city has experienced strong land subsidence and formed a huge depression covering an area of 850 km2. Flood, therefore, has become the biggest threatening to the city both at present and in the future. And from the geomorphic processes, the high pressure of human activities has caused not only the tremendous changes of character, feature and dimensions of the physical landform, but also the deformation of the land surface due to land subsidence. The former, as we known, has given rise to changes in many aspects of urban climate and hydrology. The latter has led to a more serious sedimentary accumulation in the water channels (e.g. the Suzhou Creek and the Huangpu River etc.). The fragile and catastrophic UGE (especially the irreversible land deformation) will exert influences on the future urbanization and re-urbanization of Shanghai. Facts tell us that the Shanghai's UGE must be protected effectively and used rationally to keep us on the way of healthy, sustainable urban development.