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1.
随着中国城市建设进程的加快,中国的臭氧(O3)污染逐渐受到重视。城市群是人口大国城镇化的主要空间载体,是城镇化的主体形态。截至2017年3月底,国务院共先后批复了6个国家级城市群,并提出要优化提升东部地区城市群,培育发展中西部地区城市群。另外,新的城市规模划分标准以城区常住人口为统计口径,将城市划分为5类7档。为了研究中国O3污染的时空分布特征以及O3污染与城市群之间的关系,利用地理探测器(Geographical detector)和演化树模型对2014年6月到2017年5月共36个月的O3监测数据进行时空分析。结果表明:中国O3污染水平呈现上升趋势,并在2017年迅速增长,O3已成为仅次于PM2.5的第二大污染因子,且与PM2.5在时间上呈“交错污染”的态势;O3污染超标城市绝大多数集中在城市群区域,其中长江三角洲城市群、京津冀城市群、山东半岛城市群和中原城市群相对突出;O3和PM2.5均不超标的城市主要集中在北部湾城市群和海峡西岸城市群;城市群中人口规模大的城市O3污染较为严重。  相似文献   

2.
Urban agglomeration is the main spatial organization mode used by the Chinese government to promote the policy of new urbanization strategy. Hence, a better understanding of the urban growth boundary(UGB) has profound theoretical and practical significance regarding sustainable urban development. This study devised a raster-based land use spatial optimization(LUSO) framework, and utilized ant colony optimization(ACO) algorithm to delimit the smart growth boundaries of the Changsha-Zhuzhou-Xiangtan city group(CZTCG) in China. The aim of this study is to design a LUSO model to explore an optimal pattern of urban agglomeration for sustainable growth. Multi growth scenario including a single development center, multipolar development and balanced development patterns are generated by the LUSO model for the year of 2050, and the optimum spatial pattern is chosen based on objectives comparison and the present stage of economic and social development in CZTCG. The main results are listed as the following. 1) It is feasible to identify the growth boundaries of the urban agglomeration using the land use spatial optimization model, and the optimal form of the spatial pattern can be defined. 2) With the growth trend of the urban agglomeration gradually spreads from a single center to multi-centers and even small towns, the total optimization target performance gradually increases, which means that the traditional pie-shaped development does not meet the maximum comprehensive benefit of the city group. 3) Subject to the regional social and economic development stage, absolute fair development or simply developing the central city is not conducive to promoting the coordinated development of the urban agglomeration. Gradient equalization and gradual advancement are the best choice for UGB delineation of urban agglomeration. The findings of this study would be useful to identify the UGB in CZTCG for more sustainable urban development in the future.  相似文献   

3.
系统掌握经济发展的时空格局特征能为制定经济发展战略提供决策支持。目前对经济发展时空格局的研究主要依靠统计数据。然而统计数据存在口径不统一、空间分辨率低等缺点,难以精准刻画经济发展的格局特征。夜间灯光数据具有易获取、覆盖范围广、与人类社会经济活动高度关联的优点,可以作为经济发展水平的代理变量。本文以DMSP/OLS(Defense Meteorological Satellite Program's Operational Linescan System)夜间灯光数据为基础,利用重心、标准差椭圆以及局部莫兰指数等空间分析工具从不同尺度、角度探究中国经济发展的时空格局特征。研究发现:① 2003-2013年,中国经济重心不断向东南方向移动,且移动距离呈逐年减少趋势,说明东部与内陆区域经济体量存在差异,但是差异水平正逐渐减小。中国经济的标准差椭圆范围不断扩大但是扁率减小,说明中国经济总量不断提升,但整体集聚度有所下降。同时椭圆的方向角不断向东偏转,与经济重心朝东南方向移动的结果吻合。② 高高聚集和低低聚集是中国经济发展最明显的2种类型。高高聚集区会辐射带动周边区域发展,这一特点在山东半岛和长江三角洲最明显,低低聚集主要分布在西部和东北欠发达地区。2003-2013年间,低低聚集范围有所减少,由连片分布变为局部聚集。本研究基于夜间灯光数据揭示了2003-2013年中国经济发展的时空格局特征,为制定宏观经济战略提供决策支持。  相似文献   

4.
Urban agglomeration research has received increasing attention in China's national development strategies, and has become a hot topic in academic research. This study develops a theoretical framework that explores the formation mechanism and expansion process of urban agglomerations from the perspective of industrial evolution, and identifies the development issues and their causes by taking Yangtze Delta and Beijing-Tianjin-Hebei urban agglomerations as case studies. In the process of urban agglomeration formation within a free market, as has happened in Yangtze Delta region, the central city develops first, its secondary industry is then transferred to its neighboring cities, and the work division and cooperation with the neighboring cities is gradually established. However, in the 1990 s, aiming to become an international metropolis, Beijing implemented a series of administrative policies to encourage the reduction of the secondary industry and the development of the tertiary industry, before its secondary industry were fully developed and transferred to its neighboring cities. This delayed the integration process and the development of the Beijing-Tianjin-Hebei urban agglomeration. This study builds a good foundation for the construction of the theoretical system's urban agglomeration study, and provides references for decision making in an urban agglomeration development.  相似文献   

5.
The relationship between China’s urbanization and economic development(RCUED) is an important concern nationwide. As important actors in regional strategy and policy, county-level regions have played an increasingly significant role in the development of China’s social economy. However, the existing research on the RCUED lacks the fine depiction of the county-level administrative units.Using 2000 and 2010 census data and the statistical analysis method, we uncovered the evolution characteristics of China’s urbanization and economic development and conducted a quantitative identification for the RCUED with improved methods using the quadrant map approach. In addition, we investigated the spatial correlation effect of the RCUED using the spatial autocorrelation analysis method. The results were as follows: 1) In general, a high degree of matching exists between China’s urbanization and economic development at the county level at the significance level of 0.01. The correlation coefficients between China’s urbanization and economic development in2000 and 2010 were 0.608 and 0.603, respectively. 2) A significant regional difference exists in the RCUED at the county level. Based on a comparative analysis of 2276 county units in China in the two years, we found that county units can be categorized as under-urbanized, basic coordination and over-urbanized in various areas. No situation was observed where urbanization seriously lagged behind the economic development level, so the levels of urbanization and economic development appear to be basically coordinated,and the coordination state may be gradually optimized over time. 3) Over time, the spatial dependency of the RCUED has weakened and the spatial heterogeneity has increased. Northeast China has always been an area characterized by over-urbanization. The number of county units classified as under-urbanized has begun to decline in eastern coastal urban agglomeration areas, while counties rich in resources have transformed from having point-shaped over-urbanization to plane-shaped under-urbanization along the northern border,and the number of over-urbanized county units has increased in the middle reaches of the Yangtze River. 4)’Lag-lag’ type and ’advance-advance’ type accounted for 68% of all counties in China, and these counties were shown to have obvious spatial differentiation characteristics.  相似文献   

6.
?????й????1999??????3????ε?GPS???????о?????8.0?????????????????????о?????????1)?????????????????????????????????????????????????????????壬???и????????????????????????2)???????????????????????????????????????????????????????????????????????????????????????????????????3)???????????μ?6?????????????????????????????????????????????????????????????  相似文献   

7.
Based on the analysis of its basic characteristics, this article investigated the disparities of Chinese service industry among the three regions (the eastern China, the western China and the middle China) and inter-provincial disparities of that in the three regions by Theil coefficient and cluster analysis. Then, major factors influencing its spatial disparity were explored by correlation analysis and regression analysis. The conclusions could be drawn as follows. 1) The development of Chinese service industry experienced three phases since the 1980s: rapid growth period, slow growth period, and recovery period. From the proportion of value-added and employment, its development was obviously on the low level. From the composition of industrial structure, traditional service sectors were dominant, but modern service sectors were lagged. Moreover, its spatial disparity was distinct. 2) The level of Chinese service industry was divided into five basic regional ranks: well-developed, developed, relatively-developed, underdeveloped and undeveloped regions. As a whole, the overall structure of spatial disparity was steady in 1990–2005. But there was notable gradient disparity in the interior structure of service industry among different provinces. Furthermore, the overall disparity expanded rapidly in 1990–2005. The inter-provincial disparity of service industry in the three regions, especially in the eastern China, was bigger than the disparity among the three regions. And 3) the level of economic development, the level of urban development, the scale of market capacity, the level of transportation and telecommunication, and the abundance of human resources were major factors influencing the development of Chinese service industry.  相似文献   

8.
基于1999~2007期、2009~2013期及2013~2016期GPS速度场数据,利用最小二乘配置方法解算南北地震带附近区域应变率参数,对比应变率变化并分析变化原因。结合研究时段内M_W6.0以上地震的震中分布,分析应变率参数与地震分布的相关关系;再结合地震地质,分析研究区内主要断层的地震危险性。结果显示,青藏高原近期存在加速扩展特征,其东北缘存在明显的介质性质横向不均匀特征,M_W6.0以上地震与应变率的大小存在相关关系;研究区内的地震危险区分别为祁连山中段危险区、玛沁-玛曲危险区、安宁河-小江断裂系危险区及红河断裂带中南段危险区。  相似文献   

9.
利用中国大陆1999年以来3个时段的GPS速度场,研究了汶川8.0地震前的地壳动态演化特征。研究结果显示:1)汶川地震发生在区域地壳挤压运动明显受阻的区域,孕震区附近存在一较大的障碍体,震中附近断层多年来处于强闭锁状态;2)随着地震发生日期的临近,震中西侧压性区表现出明显的向东逐步扩张态势,局部地区主压应变方向出现向北偏转,右旋剪切作用明显增强;3)汶川地震同震变形及6级以上余震分布表现出的区段性与断裂带及附近分段性运动变形特征密切相关。  相似文献   

10.
The spatial agglomeration of agricultural production is conducive to reducing planting costs, increasing production efficiency and improving product quality. It is an important way to promote the transformation and upgrad of tea industry and realize the modernization of China’s tea industry. This study used Gini coefficient and spatial autocorrelation analysis to explore the characteristics of tea spatial agglomeration in China from three geographical scales: regional level, provincial level and prefecture level from the year 2005 to 2015. The results indicated that there was a significant scale effect on the tea spatial agglomeration. The agglomeration degree increased from the regional level, provincial level to prefecture level. The types of spatial agglomeration evolution of the three scales were Ushaped, continuous diffusion, and continuous agglomeration. The spatial autocorrelation of tea production could only be found at the prefecture level. Meanwhile, at the prefecture scale, we could not only reveal the pattern changes at the regional and provincial levels, but also identify tea production agglomeration regions. Compared with the large scale, the small scale could reveal the characteristics of tea spatial agglomeration in more details. Factors such as natural resource endowments, cost factor, technological advancement, agglomeration economy, and agricultural policy influenced the evolution of tea spatial agglomeration from different geographical scales. Finally, from the perspectives of spatial transfer of tea production, promoting spatial agglomeration, building tea production bases, and breaking administrative boundaries, we proposed several policy suggestions for optimizing the spatial layout of tea production.  相似文献   

11.
In this study, an inventory analysis approach was used to investigate the intensity of agricultural non-point source pollution(ANSP) and its spatial convergence at national and provincial levels in China from 1999 to 2017. On this basis, spatial factors affecting ANSP were explored by constructing a spatial econometric model. The results indicate that: 1) The intensity of China’s ANSP emission showed an overall upward trend and an obvious spatial difference, with the values being high in the eas...  相似文献   

12.
1 INTRODUCTIONCityplaysanimportantroleintheprocessofre gionaleconomicdevelopment .Forinstance ,in 1996,thetotalmunicipalareasof 666citiesonlycoveredtheproportionof 18.12percentinnationalterritory ,andbuilt uparea 1.8percent .Buttheyproducedthe 68.63percentofGDP(GrossDo…  相似文献   

13.
Local governments have long been ardently pursuing the industrial specialization effect (MAR externalities) and industrial diversification effect (Jacobs externalities). Such a pursuit has resulted in severe distortion of resource allocation and negative effect on sustainability of local economic development. Regarding the effect from both MAR and Jacobs externalities on local economic development existing literature records notable disputes. Therefore, for local economic development, one important issue is which externality (MAR or Jacobs) can better bring the effect into play. By studying a panel data of 283 Chinese cities from 2003 to 2012 and applying dynamic plane data GMM method, this paper conducted a regression analysis of the relationship among industrial agglomeration externalities, city size, and regional economic development. The result indicates that with regard to the whole nation, MAR externalities are conducive to regional economy development whereas Jacobs externalities will, to an extent, restrain regional economic development. As regards eastern, middle, and western regions, MAR externalities are conducive only to the economic development of the eastern region; their effects on middle and western regions are insignificant. Moreover, the interaction item between MAR externalities and city size has a significant negative synergistic effect on national economic development and a certain acceleration effect on eastern region as well as a strong negative synergistic effect on the middle region and an insignificant effect on the western region. The interaction item between Jacobs externalities and city size has a positive synergistic effect on only the middle region and has an insignificant synergistic effect on both eastern and western regions. Capital stock and labor input have significant accelerating effects on GDP growth per capita of Chinese cities, whereas material capital and labor input remain primary driving forces for Chinese local economic development. Furthermore, human capital contributes to accelerating urban economic development, whereas government intervention restrains urban economic development.  相似文献   

14.
使用小波变换和功率谱估计法,利用中国静止气象卫星亮温数据研究2017年以来松原地区3次MS>4.5地震前的热红外异常。结果表明, 2017-07-23 MS4.9和2018-05-28 MS5.7地震前的异常都是沿依兰-伊通断裂和密山-敦化断裂走向逐渐扩展的,即异常存在于松辽盆地的东部边缘,地震震中不在异常区内;2019-05-18 MS5.1地震前异常不明显,可能是由于盆地内二氧化碳和甲烷等温室气体在前2次地震前后已得到最大量的释放。  相似文献   

15.
The formation and development of urban agglomeration districts are the inevitable trend of modern urban evolution. Owing to the differences of formation background, urbanized way and process of different cities in the world, the feature and formation mechanism of urban agglomeration districts in the world present obvious spatial differences. The paper inquires into the structure feature, formation mechanism and development trend of different kinds of Chinese urban agglomeration districts by studying four big urban agglomeration districts: Jing-Jin-Tang (Beijing-Tianjin-Tangshan), the middle and south of Liaoning, Hu-Ning-Hang (Shanghai-Nanjing-Hangzhou), and Zhujiang River delta. The paper wants to promote the formation and development of theory and practice system of Chinese urban agglomeration districts.  相似文献   

16.
安丘莒县断裂北段构造特征研究   总被引:1,自引:0,他引:1       下载免费PDF全文
郯庐断裂带是中国东部乃至亚洲大地构造演化中最重要的构造带,其山东段沂沭断裂带也一直是地学研究的热点,而安丘-莒县断裂更是新构造活动频发的活断层。该文在野外实际调查的基础上,从安丘-莒县断裂的控盆以及与地质体的切割关系入手,参考区域地质资料,结合物探、钻探研究成果,对安丘-莒县断裂北段的几何学、运动学特征进行了综合研究,对其新构造活动进行了初步探讨,认为早白垩世以后的"主活动"具有多阶段性、多期次性,是对早期先存断裂的继承与发展,晚更新世晚期右行走滑兼具小角度逆冲阶段。  相似文献   

17.
Comparative study on Chinese urban agglomeration districts   总被引:2,自引:1,他引:1  
COMPARATIVESTUDYONCHINESEURBANAGGLOMERATIONDISTRICTSLiChenggu(李诚固)HuangYanjun(黄岩君)UrbanandEnvironmentScienceSchol,NortheastNo...  相似文献   

18.
北京从20世纪50、60年代发现地面沉降以来,其一直呈快速发展的态势。在过去的几十年里,北京市地面沉降的范围和速度逐年增加。本文以北京市典型地面沉降区为研究区,选择永久散射体合成孔径雷达干涉测量技术所获取的2004-2010年间北京地面沉降信息作为主要数据源,补充水准测量数据(1955-2010年),从空间分布和时序变化2个角度,分析北京市平原典型区地面沉降演化特征。结合地下水动态监测网数据、土地利用数据,采用GIS空间分析,研究各因素和地面沉降之间的时空响应关系。结果表明,北京地区地面沉降严重区域面积不断扩大,且局部不均匀程度逐渐增加。在研究期内,地下水水位变化在时间和空间上与地面沉降有较高的一致性,地下水超量开采是影响北京地区地面沉降的最主要因素,而城市发展过程中的工程活动也是影响地面沉降时空分布特征的因素之一。研究结果可为北京市地面沉降防控提供一定的科学依据。  相似文献   

19.
The adjustment of administrative divisions is one of the important factors guiding China’s urbanization, which has profound economic and social effects for regional development. In this paper, we comprehensively describe the process of the adjustment of administrative divisions at provincial and municipal levels in China and summarize the effects on the basic structure and patterns of the spatial development. We quantitatively assess the effects on fields such as urbanization and social economy through the use of multidimensional scaling. The results show that: 1) Upgrading county to municipality (or city-governed district) is the main way of adjusting the administrative divisions. It is also an important factor in the spatial differentiation of interprovincial urbanization. China’s population urbanization can be divided into four patterns including interprovincial migration, provincial migration, natural growth, and growth caused by the adjustment of administrative divisions, which is also the main reason for the increased Chinese urbanization rate at the provincial level. 2) Taking the city of Beijing as an example, we generalize five adjustment patterns made to administrative divisions: the set-up of sub-districts, the set-up of regional offices, the upgrading of townships to sub-districts, the upgrading of townships to towns, and the set-up of towns and the addition of new regional offices. We summarize the municipal urban spatial structure, including the sub-district office area in the central urban area, the regional office area in the new urban area, the mixed area of villages, towns, and sub-district offices in the suburb area, and the township area in the outer suburb area. 3) The adjustment of administrative divisions triggers a significant circulative accumulation effect, resulting in the spatial locking of population and industrial agglomeration. It affects the evolution of the urban spatial form and plays an important role in shaping the urban spatial structure to move to the characteristic of multicenter. In general, the adjustment of administrative divisions was an important factor affecting the inflated statistical level of urbanization and also an important driving force for the evolution of Chinese urban spatial organization structure.  相似文献   

20.
Since the reform and opening-up program started in 1978,the level of urbanization has increased rapidly in China.Rapid urban expansion and restructuring have had significant impacts on the ecological environment especially within built-up areas.In this study,ArcGIS 10,ENVI 4.5,and Visual FoxPro 6.0 were used to analyze the human impacts on vegetation in the built-up areas of 656Chinese cities from 1992 to 2010.Firstly,an existing algorithm was refined to extract the boundaries of the built-up areas based on the Defense Meteorological Satellite Program Operational Linescan System(DMSP_OLS)nighttime light data.This improved algorithm has the advantages of high accuracy and speed.Secondly,a mathematical model(Human impacts(HI))was constructed to measure the impacts of human factors on vegetation during rapid urbanization based on Advanced Very High Resolution Radiometer(AVHRR)Normalized Difference Vegetation Index(NDVI)and Moderate Resolution Imaging Spectroradiometer(MODIS)NDVI.HI values greater than zero indicate relatively beneficial effects while values less than zero indicate proportionally adverse effects.The results were analyzed from four aspects:the size of cities(metropolises,large cities,medium-sized cities,and small cities),large regions(the eastern,central,western,and northeastern China),administrative divisions of China(provinces,autonomous regions,and municipalities)and vegetation zones(humid and semi-humid forest zone,semi-arid steppe zone,and arid desert zone).Finally,we discussed how human factors impacted on vegetation changes in the built-up areas.We found that urban planning policies and developmental stages impacted on vegetation changes in the built-up areas.The negative human impacts followed an inverted′U′shape,first rising and then falling with increase of urban scales.China′s national policies,social and economic development affected vegetation changes in the built-up areas.The findings can provide a scientific basis for municipal planning departments,a decision-making reference for government,and scientific guidance for sustainable development in China.  相似文献   

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