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1.
In metropolitan regions, the change in the strength of"flows" between a core city and surrounding cities reflects the range of the core city's influence, while the gravity between core city and other cities reflects the strength of potential relation between them. This article firstly attempts to delimit the boundary of metropolitan regions with the two dimensions measure combining "flows" and gravitation. The former is measured through the flow of people between the core city and surrounding cities, and the latter is measured through both population and gross domestic products (GDP) of the core city and surrounding cities. The hierarchy of the cities within a metropolitan region is classified in order to emphasize the roles of the cities belonging to the metropolitan regions, different from the general way through population scale and administrative level, and is typical in China. This paper uses the Shanghai metropolitan region as a research case, determining boundary of this metropolitan region clearly and classifying hierarchy of the cities within the region. The final results are significantly different to previous work, even overthrowing the traditional system of urban hierarchy partly. It is helpful to highlight the function of cities in organizing the regional economy, the level structure of metropolitan regions, and each city's relative importance in a metropolitan region, which can be taken as scientific basis for planning integrated regions or urban systems.  相似文献   

2.
The economic system of mining city is of typical vulnerability characteristics that can be manifested by its high economic sensitivity and lack of response capacity to the gradual depletion of regional mineral resources. Taking Fuxin City of Liaoning Province as a case, this paper established an economic vulnerability assessment method integrating BP neural network with vulnerability index, then carried out an economic vulnerability assessment of Fuxin during 1989–2006. The results indicate that: 1) Affected by the gradual depletion of regional mineral resources, the economic development of Fuxin had kept high economic sensitivity from 1995 to 2001, and the response capacity to cope with and adapt to the impacts of the perturbation of mineral resources was weak and relatively lag. The evolution of economic vulnerability can be divided into three stages: in 1989–1994, the economic vulnerability of Fuxin City decreased slowly; in 1995–2001, the beginning stage of economic transformation, the economic vulnerability of Fuxin City went up rapidly; in 2002–2006, the economic vulnerability of Fuxin City descended and showed a trend to be stable. 2) The influence of economic sensitivity on Fuxin’s economic vulnerability is more evident than that of response capacity. 3) The decreasing supply of mineral resources and the simple industrial structure are main factors leading to the economic sensitivity of Fuxin. 4) The improvement of economic response capacity of Fuxin has typical characteristics of input-driven growth, and external assistance is of great importance to the rapid improvement of economic response capacity of Fuxin. And 5) the change from the simple industrial structure to diversified one of Fuxin is still unaccomplished, and the contribution of non-coal-based industry to local economic development is relatively limited. Foundation item: Under the auspices of Key Program of National Natural Science Foundation of China (No. 40635030), Knowledge Innovation Programs of the Chinese Academy of Sciences (No. KZCX2-YW-342, No. KZCX2-YW-321)  相似文献   

3.
Urban expansion is a phenomenon of urban space increase, and an important measuring index of the process of urbanization. Taking Shanghai as an example, the changes of urban average height and built-up area were studied to represent city’s vertical and horizontal increases respectively, and statistical methods were used to analyze the driving forces of urban expansion. The research drew following conclusions: 1) The urban expansion process of Shanghai from 1985 to 2006 had a clear periodic feature, and could be divided into three stages: vertical expansion in dominance, coordinated vertical and horizontal expansion, and horizontal expansion in dominance. 2) The average height and quantity of buildings in core city were significantly bigger than those in suburbs, but the changing speed of the latter was faster. And 3) urbanization process was the major driving force for the city’s horizontal expansion, while industrial structure improvement was the key driving factor for the vertical expansion. Those two driving forces were simultaneously affected by city’s political factors.  相似文献   

4.
In China, community tourism is still a relatively new phenomenon, but the villagers of a small Qiang village in the Qiang Autonomous County of Beichuan in Southwestern Sichuan have initiated tourism in a way which conforms to the basic theory of community tourism development. This demonstrates that community tourism possesses a strength and vitality that can promote the development of tourism in the rural and mountainous areas. In the district of Zhenghe Village, the tourism industry, based on the community tourism model, is the mainstay of its economy. The practice of community tourism in the village not only promotes the economic development of the village community, but also leads to the protection of the mountainous natural environment and of the culture of the Qiang people. This paper investigates the development process of community tourism in Zhenghe and shows how the local residents participate in this process. It also looks at how profits have been distributed within the community. It demonstrates that community tourism is a correct choice by the Zhenghe people as they have dearly been moving from poverty to prosperity, while the local ecology and environment have been simultaneously protected. The authors hope that other minority villages with similar local conditions and natural resources will be able to use this example to develop their own community tourism.  相似文献   

5.
1 CHARACTERISTICSOFWATERTRANS FORMATIONINARIDLANDTheregularitiesofwatertransformationinstreamformingareasandstreamdisappearingareasareverydifferent.Instreamformingareas ,watertransformationismainlyfrom precipitation ,snowmeltandicemeltwatertosurfacewater…  相似文献   

6.
Numerous Quaternary deposits are existed in the mountainous areas of Southwest China,especially in the transition zone between the QinghaiTibet Plateau and the Sichuan Basin, where strong tectonic movements and frequent climatic changes increase the potential landslides. The possible deformation and failure process of potential landslides and their impacts on the surrounding environment are important research topics. Field investigation and monitoring indicate that the Qingliu landslide in Xiame...  相似文献   

7.
The coastal zone is an area characterized by intense interaction between land and sea, high sensitivity to regional environmental changes, and concentrated human activities. Little research has investigated vegetation cover changes in coastal zones resulting from climate change and land-use change, with a lack of knowledge about the driving mechanism. Normalized diff erence vegetation index(NDVI) can be used as an indicator for change of the coastal environment. In this study, we analyzed the interannual changes and spatial distribution of NDVI in the coastal zone around Jiaozhou Bay in Qingdao, a coastal city undergoing rapid urbanization in northeast China. The underlying causes of NDVI variations were discussed in the context of climate change and land-use change. Results showed that the spatio-temporal distribution of NDVI displayed high spatial variability in the study area and showed a typical trend of gradually increasing from coastal to inland regions. The significant increase area of NDVI was mainly found in newly added construction land, extending along the coastline towards the inland. Land vegetation cover demonstrated a certain response relationship to sea-land climate change and land-based activities. The impact of land-based human activities was slightly greater than that of sea-land climate change for land vegetation cover. The results indicate that promoting ecological policies can build an ecological security framework of vegetation suitable for the resource characteristics of coastal cities. The framework will buf fer the negative ef fects of sea-land climate change and land-based human activities on vegetation cover and thereby achieve the balance of regional development and ecological benefits in the coastal zone.  相似文献   

8.
China is undergoing a rapid urbanization process, and urbanization will have a direct impact on regional ecosystems and affect regional ecosystem services. Considering the mountainous counties in Southwestern China as the research object, this study reveals the spatial clustering characteristics of four typical ecosystem services(food production, soil conservation, water yield and carbon sequestration)as well as the trade-offs and synergies among ecosystem services in different urbanized areas. At the same time, piecewise linear regression is used to determine the threshold of the influence of urbanization on ecosystem services. The results indicate that: 1) There are spatial autocorrelations among the four typical ecosystem services; with strong clustering characteristics, the positive correlation types are "clustered" locally; and with significant spatial heterogeneity, the negative correlation types are scattered and mainly appear in the highly urbanized area. 2) There are also remarkable differences in the relationship among various ecosystem services in different urbanized areas, and in particular, there are marked trade-offs between food production and carbon sequestration in the moderately urbanized area and the highly urbanized area. However, there are synergies between them in the lowly urbanized area. 3) With an increase in the compounded night light index(CNLI), water yield, carbon sequestration, food production and overall ecosystem services values present an increasing-decreasing trend, the soil conservation function value shows a decreasing-increasing trend.The response of water yield, carbon sequestration,food production, and overall ecosystem services to the compounded night light index(CNLI) has a threshold of 1.2642, 1.4833, 1.3388, 1.5146 and 1.2237,respectively. Based on the detected relationships between urbanization and ecosystem services, this study provides a theoretical reference for the selection of urbanization development models in key ecological functional areas.  相似文献   

9.
Extreme and prolonged rainfall in the Tunka Ridge caused several debris flows in the vicinity of the Arshan village(Siberia, Russia) on June 28, 2014. These debris flows, in spite of similar geological conditions, had different velocity, peak discharge and alluvial fan volume values. The flow velocity was from 3.5 m/s to 19.6 m/s, the peak discharge ranged from 63 m3/s to 13566 m3/s, and the alluvial fan volume varied from 4.13×103 to 8.45×105 m3. Such a great range of values is due to the morphometric parameters of the debris flow basins. The article deals with the influence of morphometric parameters of debris flow basins, such as the basin area, the average slope, Melton ratio, relief ratio on the debris flow velocity, peak discharge and volume of alluvial fans. In this debris flow event the average values of slope angle and total basin relief of the debris flow basins did not affect the values of debris flow velocity, peak discharge and alluvial fan volume. The highest correlations were observed with the debris flow basin area that was connected with the water inflow volume into the debris flow basins during the rainfall. The unequal water distribution among debris flow basins also had an impact on the debris flow velocity, peak discharge and volume of alluvial fans.  相似文献   

10.
Previous studies on optical remote sensing mapping of landslides mainly focused on new landslides that have occurred, but little attention was paid to the early landslide due to its high concealment. In SAR technology, a prevalent method to detect early landslides, only can be used to identify the potential hazards of slow deformation. Therefore, it is necessary to explore new method of early landslides mapping by integrating all types of direct and indirect early features, such as cracks on slo...  相似文献   

11.
Taking the affinity between events and media as a conceptualization base, a total of 1032 related news reports of Expo '99 Kunming, gathered from the internet data bank of China INFOBANK from 1992 to 2003, are used as data sources. After classifying them with a communication research method--the content analysis, a data bank for SPSS is set up, and a mathematic model called the Integrated Impact Index of Expo '99 Kunming is constituted. With the model, the spatial distribution of the total integrated impacts of Expo '99 Kunming on the regions or cities with different regional scales is analysed quantitatively. The conclusions are: 1) the Expo '99 Kunming made obvious inte- grated impacts on the regions or cities of every scale, especially in the venue city and the region--Kunming City and Yunnan Province; 2) it had corresponding impacts on other provinces; 3) the spatial distribution of Integrated Impact Index had a disaggregation with both plane extension and spotted decentralization; and 4) there was a distance decay law in all three scales of regions (Kunming City, Yunnan Province and the whole China), which incarnated the spatial extension law of the integrated impact of a special mega-event.  相似文献   

12.
This paper examines the spatial-temporal dynamics of inequality from the perspective of social deprivation in the context of continuous growth of grain production using national census data from 2000 and 2010 for Henan province, China. Our analytical results show an overall level of social deprivation that is high and a widening social deprivation gap at the county level. The social deprivation shows great spatiotemporal heterogeneity, the higher deprived counties are mainly distributed in central and eastern Henan province, while counties with lower social deprivation are clustered in northwestern regions, formed a belt-shape spatial differential between the south (higher deprived counties clustered) and northwest (low deprived counties clustered) Henan in 2000, and changed toward a core-periphery semi annular spatial structure in 2010, the low deprived counties surrounded by high deprived counties. The social deprivation shows a “west low and east high” spatial pattern, similar to the grain production in Henan province. Socioeconomic development level was low in most counties in Yudong plain despite of keeping the continuous increase of grain production, meaning the higher grain output did not result in the more social development expected in Chinese traditional agricultural areas, and the regional disparity is expected to increase in the near future if development conditions are not changed, which could inspire more targeted rural governance options.  相似文献   

13.
The goal of land consolidation in China is still to develop agricultural production. The study of landscape effects of land consolidation projects (LCPs) faces many difficulties because of the lack of government's interest and data. This paper, taking Tianmen City of Hubei Province in Central China as an example, presents a methodology for analyzing landscape effects of LCPs by GIS and Fragstats3.3. It describes landscape effects with indexes of Patch Density (PD), Largest Patch Index (LPI), Landscape Shape Index (LSI), Interspersion and Juxtaposition Index (IJI), Aggregation Index (AI), and Shannon's Diversity Index (SHDI), showing more regular shape, simpler structure and less habitat diversity after LCPs. It computes ten landscape indexes of four categories of patches including Cultivated Land, Road, Water Channel, and River and Pond. The indexes show that 1) cultivated land becomes more fragmental in patch area, less irregular in patch shape and more concentrated in block; 2) the transport capacity of roads and irrigation and drainage capacity of water channels have been improved; 3) the landscape change of river and pond can be summarized as decreasing scale, more regular shape, reducing connectivity and diversity of the class. LCPs can facilitate agricultural production as well as protect cultivated land and food security. However, it is doubted that the increase of cultivated land from LCPs results from the reducing in landscape diversity of water area.  相似文献   

14.
It is great important to the health development of urban agglomeration to correctly understand the formation and development law of regional structure of urban agglomeration. Employing the analysis methods like fractal theory and quantitative statistics, coupling with the use of remote sensing images and other spatial data, this article discusses the urban agglomeration of oasis on the northern slope of the Tianshan Mountains in an arid area, and conducts the researches on its city scale, spatial distribution and individual form from 1990 to 2005. The result shows that it has loose hierarchical scale structure and polarization trend of population distribution while its hierarchical scale structure tends to mature. Under the influence of natural conditions, the spatial layout of urban agglomeration of oasis has macro characteristics that suggest cities distributed along oasis edges (dense or sparse), spatially expand along rivers, and cluster around traffic branches. The connectivity among the cities is high and shows an internal organization form of a banding distribution. The whole spatial shape of the internal structure of cities presents a “dumbbell” form, with mononuclear phenomenon receding and multi-nuclear appearing gradually. Individual cities spatially expand along rivers, portraying a long strip appearance. It indicates that the urban agglomeration of oasis shows regular and close structure but with a tendency to be complicated form and the loose structure. In the development of urban agglomeration, the authors recommend that the development of the city with good economic development conditions should be strengthened, and more attention be put into regional planning.  相似文献   

15.
Sargassum muticum is one of the most abundant and conspicuous native macroalgae species on the northern coasts of China. It often forms large-scale seaweed beds in subtidal zones. This investigation was designed to understand the intraspecific genetic relationships of this alga based on samples collected from four northern coastal sites of China, and to evaluate gamete release and growth capacity in laboratory conditions. The nuclear internal transcribed spacer 2 (ITS2) sequences of 16 samples from four locations were identical. Based on cox3 gene and partial rbcLS operon sequences, intraspecific genetic variability was detected with three and two ribotypes, respectively. Temperature, not irradiance, was shown to significantly affect gamete release and fertilization. Elevated temperature and irradiance enhanced the growth of germlings and vegetative branchlets. Maximum growth rate of germlings was detected at 18-24℃and an irradiance of 60-100 μmol photons/(m^2.s). Under ambient conditions (12-25℃ and 60-125 gmol photons/ (m2.s)), relative growth rate of young branchlets could reach 7.5%/d.  相似文献   

16.
The grounded theory of qualitative methods was applied to researching the social integration of tourism labor migrants in the Jiuhua Mountain of Anhui Province, China. The research was conducted based on the in-depth interviewing of 15 samples, open-consultation and the analysis of secondhand data. The integration models of tourism labor migrants in the Jiuhua Mountain were formed through four processes including theoretic sampling, coding-analysis, cross-tabulation and contextualization. The result shows that modes of production and life styles decide self-integration orientation of tourism labor migrants in the Jiuhua Mountain. Cultural differences are fundamental dissimilarity between tourism labor migrants and natives. There are three kinds of integration models including rapid, free and gradually advancing integration. The differences among different types of migrants' integration models are remarkable. Taking the working integration as the abscissa and taking the life integration as the coordinate, an "S" model of integration matrix appears in the gradually advancing integration of intermediate and high administers from the working to the life which should be paid special attention to.  相似文献   

17.
Communities in developing country mountain areas, in part due to their remoteness, find themselves excluded from social, political and economic systems; and excluded from access to resources. This paper aims to study the impact of information and communication technologies (ICTs) on remoteness and exclusion. It utilises two models - the resource movement framework, and the "information chain" - to analyse a telecentre in one district of mountainous Huancavelica, Peru's poorest region, set in the high Andes. It finds ICTs enabling new and positive resource flows for the two key user groups: teenaged school students and young farmers. These help to maintain social networks. They also support information searches that have improved agricultural practice where other information chain resources have been available. But non-use and ineffective use of the telecentre are found where information chain resources are lacking. ICTs have some impacts on intangible elements of remoteness. In this particular example, they also offer access to some previously-excluded resources. But they have not really addressed the systematic exclusions faced by mountain communities. And they so far appear to be a technology of inequality; favouring those residents who begin with better resource endowments. The paper concludes by offering some recommendations for mountain ICT project practice.  相似文献   

18.
Achieving sustainable livelihood is the ultimate goal of poverty alleviation efforts in mountainous areas,and selecting an optimal livelihood strategy for different poverty-type farmers greatly improves farmers’livelihood capital,resists livelihood risks,and promotes sustainable development.For farmers,optimal livelihood strategy means better employment opportunities,higher family income(or better income structure),and stronger employability or development potential.This paper classifies different types of farmers’poverty on the basis of a quantitative evaluation of farmers’livelihood capital in the Qin-ba Mountain Area in South-Shaanxi by using the k-means clustering method and subsequently the fuzzy evaluation method to evaluate the effectiveness of farmers’livelihood strategies.Then,the multi-attribute decision-making model is used to analyze the selection of optimal livelihood strategies for different poverty-type farmers.The results suggest a significant difference in the selection of the optimal livelihood strategy for different poverty-type farmers.Farmers without financial and human capital choose to"go out to work,"farmers lacking natural capital choose to"acquire social insurance and government relief,"farmers without physical capital choose to"use loans,"and farmers lacking social capital choose to"use savings."Studying the selection of optimal livelihood strategies for different poverty-type farmers can help to propose targeted sustainable livelihood optimization programs for farmers and accelerate efforts to overcome poverty in mountainous areas.  相似文献   

19.
There have been few in-depth quantitative studies on soil erosion control and the ecological effects of land use changes. Soil erosion is the first eco-environmental problem particularly in mountainous areas. A major problem in the conversion of farmland to forest is to control soil erosion and improve ecological environment and thus to improve land use sustainability. We report results of calculation and analysis on soil erosion from converted farmland parcels in city of Mangshi (near the SW frontier of China) and the surrounding areas before and after the nine-year (2000–2009) project of converting farmland to forest. There was increased water conservation effect, as a result of decreased soil erosion. The average erosion modulus of the farmland returning to eco-friendly uses decreased by 5,535.59 t/km2·a and the control degree of soil erosion modulus reached 71.00%. The increased soil erosion after the returning in the typical sample area “did not drop, but increased” as the terraced fields decreased but sloping farmland increased and yet woodland decreased.  相似文献   

20.
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