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1.
This paper attempts to summarize the disparities of lnternet development in China spatially-temporally. The major objective is to measure the differences between Eastern, Central and Western China. Methods of map presentation, correlation, Lorenz curve, Gini Coefficient and location quotient analysis are conductcd in this study.For convenience, the indicator of regional lnternet development is simplified as the number of domain names registered under .CN in each province. The data used are collected from the semi-annual surveys of the Statistical surrey Report on the Internet Development in China since 1999. There are several findings: 1)The number of domain names in each province (city) declines gradually from the east to the west. 2) The gap between the highest growth provinces (cities) and the lowest ones is rather large. 3) Although the absolute differences between the eastern, ccntral and western China have been enlarged, the relative diffcrences in each province (city) have remained constant.4) Provinces (cities) are classified into three types according to location quotient changes, namely, rising type,changeless type and declining type. Compared with industrial and economic growth, lnternet sector in the eastern and western China is relatively ascending, while that in the central China is descending. 5) The number of domain names at provincial level is not statistically consistent with GDP.  相似文献   

2.
Aimed at promoting regional coalitions and expanding the approach to economic links, this paper puts forward some new concepts such as link intensity and receiving coefficient, expounds the indexes of quantitative analysis of economic links and establishes the quantitative-analysis model of economic links. With help of the model, this paper calculates the values of the link intensities between Su-Xi-Chang (Suzhou-Wuxi-Changzhou) region and Shanghai, and analyzes the regional difference of the economic links.  相似文献   

3.
MODELING OF REGIONAL DIFFERENTIATION OF LAND-USE DEGREE IN CHINA   总被引:1,自引:0,他引:1  
Thestudyonland--useandland--coverchangesbecomesmoreandmoreimPOrtantinglobalenvironmentchangeresearch.AglobalresearchplannamedLUCCwasfoundedbyIGHPandHIJPin1995andonecoreprojectplanandprojectocr-nmittee(CPPCmePELUCC)wasalsofounded.Aninternationalconferenceonland--useandland--coverchangeswasheldintheNetherlands.Inthisconference,fiveframequestions(IGBP,1996)andthreeresearchfocuses(IGBP,1996)havebeenproPOsed.Studyonland--useandland-coverchangesPOssessesanimPOrtantPOsitioninthefield…  相似文献   

4.
Regional climate models have become the powerful tools for simulating regional climate and its change process and have been widely used in China. Using regional climate models, some research results have been obtained on the following aspects: 1) the numerical simulation of East Asian monsoon climate, including exceptional monsoon precipitation, summer precipitation distribution, East Asian circulation, multi-year climate average condition, summer rain belt and so on; 2) the simulation of arid climate of the western China, including thermal effect of the Qinghal-Tibet Plateau, the plateau precipitation in the Qilian Mountains; and the impacts of greenhouse effects (CO2 doubling) upon climate in the western China; and 3) the simulation of the climate effect of underlying surface changes, including the effect of soil on climate formation, the influence of terrain on precipitation, the effect of regional soil degradation on regional climate, the effect of various underlying surfaces on regional climate, the effect of land-sea contrast on the climate formulation, the influence of snow cover over the plateau regions on the regional climate, the effect of vegetation changes on the regional climate, etc. In the process of application of regional climate models, the preferences of the models are improved so that better simulation results are gotten. At last, some suggestions are made about the application of regional climate models in regional climate research in the future.  相似文献   

5.
1INTRODUCTIONThere have been many literatures about the regional disparity of economic development in China since the late 1970s. Some scholars argue that disparity of re-gional development in China has been expanded since 1978, but others find it has reduced since 1978. The findings of some scholars show that the evolutionary process of the disparity of regional economic develop-ment in China follows the inverted U shape, but some others do not think so. What is the true tendency, and i…  相似文献   

6.
Newest planning methods implemented by Chinese government are promoting a coordinated regional development and shaping an orderly spatial structure by applying the regulation of territorial function. This article analyzes the problems of spatial planning and regional strategy caused by the wrongly-set primary goal of economic development; it states that the three-fold objective of competitiveness, sustainability, and welfare fairness shall be the principal for China to implement the spatial regulation in the new era; it discusses about theoretical thoughts and technology framework of conducting the ′Major Function Oriented Zone′ based on their different major functions that each region plays in urbanization and industrialization, ecological constructions, grain productions, and protection of natural and cultural heritages; it introduces the new concept of ′Major Function Oriented Zone′ that include the major functions category, the stereo regional equilibrium mode, the two-level zoning specification, and the territorial development intensity; it offers a zoning scheme that defines development-optimized and development-prioritized zones as regions with massive urbanization and industrialization, development-restricted zones as ecological constructing or grain producing regions, development-prohibited zones as natural and cultural heritage protecting regions; and finally it addresses the main obstacle for implementing ′Major Function Oriented Zone′, which is the institutional arrangement of the supreme goal of high GDP growth rate that is currently being implemented.  相似文献   

7.
The objective of this study is to develop a unique modeling approach for fast assessment of massive soil erosion by water at a regional scale in the Loess Plateau, China. This approach relies on an understanding of both regional patterns of soil loss and its impact factors in the plateau area. Based on the regional characteristics of pre- cipitation, vegetation and land form, and with the use of Landsat TM and ground investigation data, the entire Loess Plateau was first divided into 3 380 Fundamental Asses...  相似文献   

8.
ONREGIONALDIFFERENTIATIONOFRIVERWATERENVIRONMENTCAPACITYANDSTRATEGIESTOCONTROLWATERENVIRONMENTPOLLUTIONINCHINA¥WangHuadong(王华...  相似文献   

9.
Using the daily maximum and minimum temperature dataset from 128 stations from 1960 to 2004 in Northwest China, daily extreme high temperature (EHT) and extreme low temperature (ELT) thresholds were determined by centesimal method for different stations at first, then yearly EHT and ELT events were counted up in different stations, and the characteristics of their spatio-temporal distribution were diagnosed at last. The study drew following conclusions: 1) The consistent anomaly distribution characteristic was the most important mode of the EHT and ELT events in Northwest China. 2) The spatial distribution of the EHT and ELT events can be divided into five sub-regions, namely, the north of Qinghai and west of Gansu, the north of Xinjiang, the south of Xinjiang, the east of Northwest China and the south of Qinghai. 3) The EHT events showed remarkable increasing trend in all of five sub-regions, but only in the north of Qinghai and west of Gansu area, sudden change phenomenon occurred; the ELT events showed decreasing trend in all of five sub-regions, and sudden change phenomenon occurred in Northwest China except for south of Qinghai. 4) In all of five sub-regions the EHT events showed remarkable 12-14yr period oscillation, and the ELT event showed significant 13-15yr and 7-8yr period oscillation. 5) The EHT and ELT events displayed remarkable positive and negative responses to regional warming of Northwest China respectively.  相似文献   

10.
This paper firstly investigated the land-use and land-cover change (LUCC) in the Hun-Taizi River watershed, Northeast China from 1988 to 2004 based on remotely sensed images and geographic information systems (GIS) technology. Then, using the famous land-use change model of Conversion of Land Use and its Effects at Small regional extent (CLUE-S), this paper simulated the land use changes under historical trend (HT), urban planning (UP) and ecological protection (EP) scenarios considering urban planning and ...  相似文献   

11.
The rate of regional sea level rise(SLR) provides important information about the impact of human activities on climate change.However,accurate estimation of regional SLR can be severely affected by sea surface height(SSH) change caused by the Pacific Decadal Oscillation(PDO-SSH).Here,the PDOSSH signal is extracted from satellite altimeter data by multi-variable linear regression,and regional SLR in the altimeter era is calculated,before and after removing that signal.The results show that PDO-SSH trends are rising in the western Pacific and falling in the eastern Pacific,with the strongest signal confined to the tropical and North Pacific.Over the past 20 years,the PDO-SSH accounts for about 30%-40%of altimeter-observed SLR in the regions 8°-15°N,130°-160°E and 30°-40°N,170°-220°E.Along the coast of North America,the PDO-SSH signal dramatically offsets the coastal SLR,as the sea level trends change sign from falling to rising.  相似文献   

12.
The stability of slopes is always of great concern in the field of rock engineering. The geometry and orientation of pre-existing discontinuities show a larger impact on the behavior of slopes that is often used to describe the measurement of the steepness, incline, gradient, or grade of a straight line. One of the structurally controlled modes of failure in jointed rock slopes is plane failure. There are numerous analytical methods for the rock slope stability including limit equilibrium, stress analysis and stereographic methods. The limiting equilibrium methods for slopes under various conditions against plane failure have been previously proposed by several investigators. However, these methods do not involve water pressure on sliding surfaces assessments due to water velocity and have not yet been validated by case study results. This paper has tried to explore the effects of forces due to water pressure on discontinuity surfaces in plane failure through applying the improved equations. It has studied the effect of water flow velocity on sliding surfaces in safety factor, as well. New equations for considering water velocity (fluid dynamics) are presented. To check the validity of the suggested equations, safety factor for a case study has been determined. Results show that velocity of water flow had significant effect on the amount of safety factor. Also, the suggested equations have higher validity rate compared to the current equations.  相似文献   

13.
Qinghai Province is an important component of the Qinghai-Tibet Plateau in China. Scientific evaluation of the suitability of Qinghai’s climate for tourism can contribute to overcoming obstacles posed by climate on sustainable tourism development in Qinghai Province, including disparities between the low and high seasons, high altitude health concerns, and weather events. A tourism climate suitability evaluation model of the Qinghai-Tibet Plateau is constructed (Tourism Climate Suitability Index, or TCSI), and tourism climate suitability is comprehensively evaluated for Qinghai Province from climate data from 1960 to 2009. Results show that: (I) There is clear distributional characteristics of spatial-temporal variability of TCSI values in Qinghai Province. (II) Tourism climate suitability in Qinghai Province has significant seasonal and regional differences. The year is divided into a very suitable period (July and August), suitable tourism periods (from April and October), less suitable periods (From Nov to Mar). June to August is the most suitable tourism period in Qinghai. Qinghai Province is divided into five levels of tourism climate suitability: most suitable regions, very suitable regions, suitable regions, less suitable regions, and unsuitable region. (III) The key factor which influences regional differences in tourism climatic suitability is atmospheric oxygen. And the key factors which chiefly influence seasonal differences of tourism climate suitability are temperature and humidity, the wind chill factor, and barrier weather.  相似文献   

14.
15.
A new species of deep-water barnacle that belongs to the family Scalpellidae is described from the South China Sea. A rcoscalpellum liui sp. nov. is morphologically similar to A rcoscalpellum gryllum Zevina,but differs from the latter by the absence of longitudinal striae on the capitular plates and the presence of caudal appendages with few terminal setae.  相似文献   

16.
China is a country with a vast marine territory whose area covers one third of the total land territory area. With the exploitation of marine resources and the development of marine economy, marine economic regions have been formed gradually. We shouldn’t ignore them when we divide economic regions throughout the whole nation, especially in our country. In this paper, we’ Il expand division principles, practice and methods of marine comprehensive economic region. Liaoning Province, facing the Yellow Sea and the Bohai sea, is not only a part of Round-the-Bohai Sea Economic Region, but a part of national marine econemic region. Through evaluating marine resources of Liaoning, and analyzing development of marine economy, composition of marine industries and distributional characteristic of marine economy, Liaoning marine region is divided into Bohai Sea marine economic region and Yellow Sea marine economic region based on differences of marine economy. Thereby we go further into the formation of regional marine economic region and distributional mechanism of regional marine economy. Foundation item: Subsidized by the National Natural Science Foundation of China(49671022). Biography: ZHANG Yao-guang(1934–), male, a native of Shanghai City, professor. His research interest includes marine economic geography.  相似文献   

17.
The study shows that the regional differentiation of Hong Kong direct investment (HKDI) in China was enlarged in the 1980s and has been reducing since 1991. The concentration of HKDI in the southern China and the coast has been replaced by the trend of moving northwards and inlandwards after 1989. But in terms of manufacturing sectors this trend has not clearly appeared until now. Those changing patterns are clearly related to the behaviour of Hong Kong industrial investors. The survey results suggest that “enjoying lower production cost” is the most important motive for their investment in China. In consequence, “close to Hong Kong”, “cheaper labour” and “favourable policy” are major factors for determining the investment locations. This behaviour, together with the lack of comparison study in location selection among most investors, explains that Guangdong absorbed most Hong Kong investment in the 1980s. As the production costs have been increasing in Guangdong, some companies have started to invest in non-Guangdong locations since the end of the 1980s. From the mental map of Hong Kong investors, however, only some of the non-Guangdong locations are practically attractive. Supported by National Natural Science Foundation of China and the University Graduates Association (Hong Kong). The author gratefully acknowledges the help from Professors Kam-hon Lee and Yue-man Yeung and Dr. David Chu at the Chinese University of Hong Kong, and Mr. Chai-ming Mak at Electricity Advisory Services Limited (HK) during the early stage of the study.  相似文献   

18.
A regional multiple-objective water-resource and economic optimization model was developed using a quantitative method of systematic analysis.Input to the model includes indexes of economic structure and development,water-resource utilization,wastewater and pollutant discharge,and investment in wastewater treatment.The model,which consists of producton-structure and industrial-structure optimization modules,was applied to the Guanzhong region in the middle reaches of the Huanghe(Yellow) River basin in China.By evaluating several alternative production and industrialization schemes,the modal indicate that water pollution will get worsen though wastewater treatment improves if the economy continues to develop at the planned speed without structural adjustment.However,the results also show that not only economic goals but also water-resource protection and pollution-control targets can be achieved under an alternative,recommended production and industrial structure.This example illustrates that economic development and environmental protection can be improved coordinately by the regional multiple-objective water-resource and economic optimization model.It provides an operable approach to the simultaneous sustained development of water resources and economic growth.  相似文献   

19.
Three-River Headwaters(TRH) region involved in this paper refers to the source region of the Changjiang(Yangtze) River,the Huanghe(Yellow) River and the Lancang River in China.Taking the TRH region of the Qinghai-Tibet Plateau as a case,the annual evapotranspiration(ET) model developed by Zhang et al.(2001) was applied to evaluate mean annual ET in the alpine area,and the response of annual ET to land use change was analyzed.The plant-available water coefficient(w) of Zhang’s model was revised by using vegetation-temperature condition index(VTCI) before annual ET was calculated in alpine area.The future land use scenario,an input of ET model,was spatially simulated by using the conversion of land use and its effects at small regional extent(CLUE-S) to study the response of ET to land use change.Results show that the relative errors between the simulated ET and that calculated by using water balance equation were 3.81% and the index of agreement was 0.69.This indicates that Zhang’s ET model based on revised plant-available water coefficient is a scientific and practical tool to estimate the annual ET in the alpine area.The annual ET in 2000 in the study area was 221.2 mm,11.6 mm more than that in 1980.Average annual ET decreased from southeast to northwest,but the change of annual ET between 1980 and 2000 increased from southeast to northwest.As a vast and sparsely populated area,the population in the TRH region was extremely unbalanced and land use change was concentrated in very small regions.Thus,land use change had little effect on total annual ET in the study area but a great impact on its spatial distribution,and the effect of land use change on ET decreased with increasing precipitation.ET was most sensitive to the interconversion between forest and unused land,and was least sensitive to the interconversion between cropland and low-covered grassland.  相似文献   

20.
In this paper,we proposed a framework for evaluating the performance of ecosystem strategies prepared for enhancing vulnerability reduction in the face of hazards due to climate change.The framework highlights the positive effects of human activities in the coupled human and natural system(CHANS) by introducing adaptive capacity as an evaluation criterion.A built-in regional vulnerability to a certain hazard was generated based upon interaction of three dimensions of vulnerability:exposure,sensitivity and adaptive capacity.We illustrated the application of this framework in the temperate farming-grazing transitional zone in the middle Inner Mongolia of the northern China,where drought hazard is the key threat to the CHANS.Specific indices were produced to translate such climate variance and social-economic differences into specific indicators.The results showed that the most exposed regions are the inner land areas,while counties located in the eastern part are potentially the most adaptive ones.Ordos City and Bayannur City are most frequently influenced by multiple climate variances,showing highest sensitivity.Analysis also indicated that differences in the ability to adapt to changes are the main causes of spatial differences.After depiction of the spatial differentiations and analysis of the reasons,climate zones were divided to depict the differences in facing to the drought threats.The climate zones were shown to be similar to vulnerability zones based on the quantitative structure of indexes drafted by a triangular map.Further analysis of the composition of the vulnerability index showed that the evaluation criteria were effective in validating the spatial differentiation but potentially ineffective because of their limited time scope.This research will be a demonstration of how to combine the three dimensions by quantitative methods and will thus provide a guide for government to vulnerability reduction management.  相似文献   

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