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1.
China is physically and socio-economically susceptible to global warming-derived high temperature extremes because of its vast area and high urban population density. This article presents a scenario-based analysis method for high temperature extremes aimed at illustrating the latter’s hazardous potential and exposure across China. Based on probability analysis, high temperature extreme scenarios with return periods of 5, 10, 20, and 50 years were designed, with a high temperature hazard index calculated by integrating two differentially-weighted extreme temperature indices (maximum temperature and high temperature days). To perform the exposure analysis, a land use map was employed to determine the spatial distribution of susceptible human activities under the different scenarios. The results indicate that there are two heat-prone regions and a sub-hotspot occupying a relatively small land area. However, the societal and economic consequences of such an environmental impact upon the North China Plain and middle/lower Yangtze River Basin would be substantial due to the concentration of human activities in these areas.  相似文献   

2.
Topographical relief is a key factor that limits population distribution and economic development in mountainous areas. The limitation is especially apparent in the mountain-plain transition zone. Taking the transition zone between the Qinling Mountains and the North China Plain(i.e. the mountainous area in western Henan Province) as an example and based on the 200-m resolution DEM data, we used the mean change-point analysis to determine the optimal statistical unit for topographical relief, and thereafter extracted the relief degree. Taking the 1:100,000 land use data, township population and county-level industrial data, population and economic spatial models were constructed, and 200-m resolution grid population and economic density maps were generated. Afterwards, statistical analysis was carried out to quantitatively reveal the impact of topographical relief on population and economy. In addition, the impacts of other topographical factors were discussed. The results showed the following.(1) The relief degree in western Henan is generally low, where 58.6% of the regional topography does not exceed half the height of a reference mountain(relative elevation ≤250 m). Spatially, the relief degree is high in the west while low in the east, and high in the middle while low in the north and south. There is a positive correlation between relief degree and elevation, and a much stronger correlation between relief degree and slope.(2) The linear fitting degree between the population and economic validation data and the corresponding simulation data are 0.943 and 0.909, respectively, indicating that the spatialized results can reflect the actual population and economic distribution.(3) The impact of topographical relief on population and economy was stronger than that of other topographical factors. The relief degree showed a good logarithmic fit relationship with population density(0.911) and economic density(0.874). Specifically, 88.65% of the population lives in areas where the topographical relief is ≤0.5 and 88.03% of the gross regional product was from areas where the relief is ≤0.3. Compared with the population distribution, the economic development showed an obvious agglomeration trend towards low relief areas.  相似文献   

3.
中国的地形起伏度及其与人口分布的相关性   总被引:9,自引:2,他引:7  
The relief degree of land surface (RDLS) is an important factor for describing the landform at macro-scales. This study defines a concept for RDLS and applies the concept for population distribution study of the entire country. Based on the concept and macro-scale digital elevation model datum and ARC/INFO software, the RDLS at a 10 km×10 km grid size of China is extracted. This paper depicts systemically the spatial distributions of RDLS through analyzing the ratio structure and altitudinal characters of RDLS in China. The conclusions are drawn as follows: the RDLS in more than 63% of the area is less than one (1) (relative altitude is less than 500 m), reflecting the fact that most of RDLS in China is low. In general, the RDLS in the west is larger than that in the east and so is the south than that of the north in China. The RDLS decreases with the increase of longitude and latitude and the change of RDLS at the latitudes of 28°N, 35°N, 42°N, as well as at the longitudes of 85°E, 102°E, 115°E could reflect the three major ladders of China. In the vertical direction, the RDLS increases with the increase of altitude. Analysis of the correlation between RDLS and population distribution in China and its regional difference shows that the R2 value between RDLS and population density is 0.91 and RDLS is an important factor influencing the spatial distribution of population. More than 85% of the people in China live in areas where the RDLS is less than one (1), while the population in areas with RDLS greater than 3 accounts only for 0.57% of the total. The regional difference of correlation between RDLS and population within China is significant and such correlation is significant in Central China and South China and weak in Inner Mongolia and Tibet.  相似文献   

4.
近5年青海省植被覆盖变化的遥感监测   总被引:3,自引:2,他引:1  
This paper used five years (2001-2006) time series of MODIS NDVI images with a 1-km spatial resolution to produce a land cover map of Qinghai Province in China. A classification approach for different land cover types with special emphasis on vegetation, especially on sparse vegetation, was developed which synthesized Decision Tree Classification, Supervised Classification and Unsupervised Classification. The spatial distribution and dynamic change of vegetation cover in Qinghai from 2001 to 2006 were analyzed based on the land cover classification map and five grade elevation belts derived from Qinghai DEM. The result shows that vegetation cover in Qinghai in recent five years has been some improved and the area of vegetation was increased from 370,047 km^2 in 2001 to 374,576 km^2 in 2006. Meanwhile, vegetation cover ratio was increased by 0.63%. Vegetation cover ratio in high mountain belt is the largest (67.92%) among the five grade elevation belts in Qinghai Province. The second largest vegetation cover ratio is in middle mountain belt (61.80%). Next, in the order of the decreasing vegetation cover ratio, the remaining grades are extreme high mountain belt (38.98%), low mountain belt (25.55%) and flat region belt (15.46%). The area of middle density grassland in high mountain belt is the biggest (94,003 km^2), and vegetation cover ratio of dense grassland in middle mountain belt is the highest (32.62%), and the increased area of dense grassland in high mountain belt is the greatest (1280 km^2). In recent five years the conversion from sparse grass to middle density grass in high mountain belt has been the largest vegetation cover variation and the converted area is 15931 km^2.  相似文献   

5.
Urban land cover has major impacts on a city’s ecosystem services and the inherent quality of its urban residential environment. The spatio-temporal distribution of impervious surface area and green areas in Chinese cities has exhibited a significantly marked difference in comparison with USA cities. This study focused on monitoring and comparing the spatio-temporal dynamics, land cover patterns and characteristics of functional regions in six Chinese(n=3) and USA(n=3) cities. The study data were collated from Landsat TM/MSS imagery during the period 1978–2010. Results indicate that Chinese cities have developed compactly over the past three decades, while development has been notably dispersed among USA cities. Mean vegetation coverage in USA cities is approximately 2.2 times that found amongst Chinese urban agglomerations. Land use types within Chinese cities are significantly more complex, with a higher density of impervious surface area. Conversely, the central business district(CBD) and residential areas within USA cities were comprised of a lower proportion of impervious surface area and a higher proportion of green land. Results may be used to contribute to future urban planning and administration efforts in both China and the USA.  相似文献   

6.
中国分县生态承载力供需平衡空间格局分析(英文)   总被引:5,自引:1,他引:4  
A balanced ecological carrying capacity and its understanding are important to achieve sustainable development for human kind.Here,the concept of ecological carrying capacity has been used for measuring the dependencies between human and nature.China’s ecological balance between supply and demand has become a global concern and is widely debated.In this study the ’Ecological Footprint’ method was used to analyze the supply-demand balance of China’s ecological carrying capacity.Firstly,the ecological supply and demand balance was calculated and evaluated,and secondly,the ecological carrying capacity index (ECCI) was derived for each county of China in 2007,and finally this paper systematically evaluated the ecological carrying capacity supply-demand balance of China.The results showed that ecological deficit appeared to be the main characteristic of ecological carrying capacity supply-demand balance in 2007 of China at county scale.In general,more than four-fifths of the Chinese population was concentrated in less than one-third of the land area and more than two-thirds of the land area was inhabited by less than one-fifth of the population.The spatial distribution of the ecological carrying capacity demand-supply was unbalanced ranging from significant overloading to affluence from southeastern to northwestern part of China.It appeared to be more dominant in regions located at coastal areas which are attracted by migrants and had a generally higher population density.Along with the rapid development and urbanization trends in China,ecological deficits in these regions will become more severe.  相似文献   

7.
长江上游社会经济因子对侵蚀产沙的影响   总被引:1,自引:0,他引:1  
In recent years,the role of human activities in changing sediment yield has become more apparent for the construction of hydraulic engineering and water conservation projec-tions in the Upper Yangtze River,but it has not been evaluated at the macro scale.Taking Sichuan Province and Chongqing City as an example,this paper studies the relationship between socio-economic factors and sediment yield in the Upper Yangtze River based on section data in 1989 and 2007.The results show that sediment yield is significantly correlated with population density and cultivated area,in which the former appears to be more closely related to sediment yield.Moreover,in the relation of sediment yield vs.population density,a critical value of population density exists,below which the sediment yield increases with the increase of population density and over which the sediment yield increases with the decrease of population density.The phenomenon essentially reflects the influence of natural factors,such as topography,precipitation and soil property,and some human activities on sediment yield.The region with a higher population density than critical value is located in the east of the study area and is characterized by plains,hills and low mountains,whereas the opposite is located in the west and characterized by middle and high mountains.In the eastern region,more people live on the lands with a low slope where regional soil erosion is slight;therefore,sediment yield is negatively related with population density.In contrast,in the western region,the population tends to aggregate in the areas with abundant soil and water resources which usually lead to a higher intensity of natural erosion,and in turn,high-intensity agricultural practices in these areas may further strengthen local soil erosion.It is also found that popu-lation tends to move from the areas with bad environment and high sediment yield to the areas with more comfortable environment and less sediment yield.The natural factors have greater influence on sediment yield of western region than that of eastern region.Generally,the natural factors play a dominant role on sediment yield in the Upper Yangtze River.  相似文献   

8.
1987-2007年土耳其伊斯坦布尔黑海沿岸土地利用变化(英文)   总被引:1,自引:0,他引:1  
Recently,important land use changes have occurred in the Black Sea coastal regions of stanbul due to urban growth and population increases.The objective of this study was to determine changes in land use in the Black Sea coastal regions of stanbul between 1987 and 2007.Landsat 30 m satellite images from 1987 and 2007 are used in the study.The study area is 1000 m in width from the coastline to the land and the study has been carried out using the controlled classification method to classify areas into residential,agricultural,forest,bare land,brush/grassland,and lake/pond land classes.Land use changes between 1987 and 2007 were analysed in detail.Residential areas of the Black Sea coastal regions of stanbul increased by 122% over the two decades.Also an increase of 55% in agriculture areas was observed,while there were decreases of 26% in forest areas and 15% in free land.A 21% increase in the area of brush and grassland took place.Furthermore 79% of the study area was covered by residential areas in 2007.It is probable that pressure on the stanbul coastal regions will continue due to migraton and rapid urbanization.Therefore,Istanbul’s Black Sea coastal regions should be maintained using a sustainable coastal management plan.  相似文献   

9.
中国畜禽养殖的空间分析及分区研究(英文)   总被引:3,自引:1,他引:2  
The capacity of livestock breeding in China has increased rapidly since 1949, and the total output of meat, poultry and eggs maintains the world’s top first in recent 20 years. Livestock emissions and pollution is closely associated with its population and spatial distribution. This paper aims to investigate the spatial patterns of livestock and poultry breeding in China. Using statistical yearbook and agricultural survey in 2007, the county-level populations of livestock and poultry are estimated as equivalent standardized pig index (ESP), per cultivated land pig index (PCLP) and per capita pig index (PCP). With the help of spatial data analysis (ESDA) tools in Geoda and ArcGIS software, especially the Moran’s I and LISA statistics, the nationwide global and local clustering trends of the three indicators are examined respectively. The Moran’s I and LISA analysis shows that ESP and PCP are significantly clustering both globally and locally. However, PCLP is clustering locally but not significant globally. Furthermore, the thematic map series (TMS) and related gravity centers curve (GCC) are introduced to explore the spatial patterns of livestock and poultry in China. The indicators are classified into 16 levels, and the GCCs for the three indicators from level 1 to 16 are discussed in detail. For districting purpose, each interval between gravity centers of near levels for all the three indicators is calculated, and the districting types of each indicator are obtained by merging adjacent levels. The districting analysis for the three indicators shows that there exists a potential uniform districting scheme for China’s livestock and poultry breeding. As a result, the China’s livestock and poultry breeding would be classified into eight types: extremely sparse region, sparse region, relatively sparse region, normally sparse region, normal region, relatively concentrated region, concentrated region and highly concentrated region. It is also found that there exists a clear demarcation line between the concentrated and the sparse regions. The line starts from the county boundary between Xin Barag Left Banner and Xin Barag Right Banner, Inner Mongolia Autonomous Region to the west coast of Dongfang County, Hainan Province.  相似文献   

10.
北京城市蔓延的测度与分析   总被引:5,自引:2,他引:3  
Concerning about the rapid urban growth in recent China, this study takes Beijing as a case and puts forward that urban sprawl can be measured from spatial configuration, urban growth efficiency and external impacts, and then develops a geo-spatial indices system for measuring sprawl, a total of 13 indicators. In order to calculate these indices, different sources data are selected, including land use maps, former land use planning, land price and floor-area-ratio samples, digitized map of the highways and city centers, population and GDP statistical data, etc. Various GIS spatial analysis methods are used to spatialize these indices into 100m×100m cells. Besides, an integrated urban sprawl index is calculated by weight sum of these 13 indices. The application result indicates that geo-spatial indices system can capture most of the typical features and interior differentia of urban sprawl. Construction land in Beijing has kept fast growing with large amount, low efficiency and disordered spatial configuration, indicating a typical sprawling tendency. The following specific sprawl features are identified by each indicator: (1) typical spatial configuration of sprawling: obvious fragmentation and irregularity of landscape due to unsuccessful enforcement of land use planning, unadvisable pattern of typical discontinuous development, strip development and leapfrog development; (2) low efficiency of sprawl: low development density, low population density and economic output in newly developed area; and (3) negative impacts on agriculture, environment and city life. According to the integrated sprawl index, the sprawling amount in the northern part is larger than that in the southern, but the sprawling extent is in converse case; most sprawling area include the marginal area of the near suburbs and the area between highways, etc. Four sprawling patterns are identified: randomly expansion at urban fringe, strip development along or between highways, scattered development of industrial land, leapfrog development of urban residence and industrial area.  相似文献   

11.
In this paper, with the spatial analysis functions in ArcGIS and the county-level census data of 2000 in China, the population density map was divided and shown by classes, meanwhile, the map system of population distribution and a curve of population centers were formed; in accordance with the geographical proximity principle, the classes of population densities were reclassified and a population density map was obtained which had the spatial clustering characteristic. The multi-layer superposition based on the population density classification shows that the population densities become denser from the Northwest to the Southeast; the multi-layer clustering phenomenon of the Chinese population distribution is obvious, the populations have a water-based characteristic gathering towards the rivers and coastlines. The curve of population centers shows the population densities transit from the high density region to the low one on the whole, while in low-density areas there are relatively dense areas, and in high-density areas there are relatively sparse areas. The reclassification research on the population density map based on the curve of population centers shows that the Chinese population densities can be divided into 9 classes, hereby, the geographical distribution of Chinese population can be divided into 9 type regions: the concentration core zone, high concentration zone, moderate concentration zone, low concentration zone, general transitional zone, relatively sparse area, absolute sparse area, extreme sparse area, and basic no-man's land. More than 3/4 of the population of China is concentrated in less than 1/5 of the land area, and more than half of the land area is inhabited by less than 2% of the population, the result reveals a better space law of China’s population distribution.  相似文献   

12.
中国人口分布的密度分级与重心曲线特征分析   总被引:37,自引:5,他引:32  
依据2000年全国第五次人口普查数据,利用ArcGIS的空间分析功能,将人口密度图分层显示,并形成中国人口分布图系.在此基础上,建立人口重心曲线,根据人口重心曲线上点的邻近性实施人口密度再分级,由此获得了更具空间集聚特征的人口密度图.基于人口密度分级的多圈层迭加分析表明:随着人口密度增大,人口分布重心逐渐由西北向东南移动,由稀疏趋于稠密,中国人口分布多圈层集聚特征明显.人口重心曲线表明,人口分布总体上是从高密度向低密度分布过渡的,其中在低密度中也有高密度地区分布,高密度地区也有相对稀疏的地区.基于人口重心曲线的中国人口密度再分级表明,中国人口密度可以适度划分为9级,据此可以将中国人口地理分布划分为集聚核心区、高度集聚区、中度集聚区、低度集聚区、一般过渡区、相对稀疏区、绝对稀疏区、极端稀疏区、基本无人区等9大类型区.统计表明,中国3/4以上的人口集中分布在不到1/5的国土面积上,半数以上的国土面积上居住着不到2%的人口,研究结果较好地揭示了中国人口分布的空间规律性.  相似文献   

13.
中国畜禽养殖的空间格局与重心曲线特征分析   总被引:10,自引:1,他引:9  
付强  诸云强  孙九林  孔云峰 《地理学报》2012,67(10):1383-1398
以中国畜禽养殖的空间格局为研究目标, 利用2007 年分县的统计数据及农业调查数据, 构建标准猪、地均猪、人均猪等指标, 使用GeoDa、ArcGIS 等软件, 借助全局和局部空间自相关分析、空间分布图系、重心曲线等方法, 对中国县域畜禽养殖空间分布规律、空间格局进行分析。主要结论:① 空间聚类趋势分析表明, 标准猪和人均猪在全国和局部聚集特征都显著, 而地均猪在全国的聚集特征不明显, 局部有聚集特征;② 虽然标准猪、地均猪和人均猪等不同的刻画方式对应着不同的分布图系、重心曲线和不同的分区方案, 但是却存在着潜在的统一分区方案。只是, 每一分区中各级别重心的归属依据与相邻级别重心的间距进行调整。由此, 中国畜禽养殖可分为畜养极疏区、稀疏区、相对稀疏区、一般稀疏区、一般区、相对密集区、密集区、高密区等8 个区;③ 存在着一条畜禽养殖疏密分界线, 该线自内蒙古新巴尔虎左右旗交界处到海南省东方市西海岸。  相似文献   

14.
城镇化过程中山区人口分布的时空特征及其变化规律对协调人地关系和实施乡村振兴具有十分重要的意义。论文基于河南省洛阳市3次农业普查数据,选取嵩县318个村域单元为研究对象,综合运用GIS空间分析和回归方法,分析该县域人口分布的时空演变特征及其影响因素。结果表明:① 嵩县人口分布在空间上极不均衡,高密度区集聚于交通干线附近和地势较为平坦的地区,并随时间推移由点状集聚分布向片状和条带状集聚分布转变;② 人口增长总体上以洛栾高速为界,西北人口增长速度快、东南人口增长速度慢,其中高速增长区主要集中于县城及洛栾高速西北部少数乡镇所在地;③ 人口增长中心位于县城和陆浑水库周围的乡镇所在地,南部深山区乡镇有望形成新的人口集聚地;④ 县域人口分布格局是自然地理条件、地理区位和公共服务设施共同作用的结果。其中,县城可达性对人口分布影响最大,地形起伏度次之,耕地面积和中学可达性较小,但不同因素的影响具有时空异质性。上述结论意味着,山区县可在充分考虑自然条件和资源禀赋差异的基础上,利用城镇化布局、基础设施建设和公共服务设施调整来促进县域人口分布格局的优化。  相似文献   

15.
基于乡镇尺度的河南省人口分布的地统计学分析   总被引:5,自引:1,他引:4  
基于地统计学方法,以乡镇层面的第六次人口普查数据为基础,对河南省人口分布及其影响因素进行分析。结果表明:全省人口分布基本上可划分为山区低密度、平原中密度和城市高密度三种类型;变异函数在东西、南北、东北—西南和西北—东南四个方向上趋向相近,距离超过80 km后,各向异性增强;变异函数的指数模型拟合效果最好,插值结果直观地表现了人口疏密的梯度变化;洛阳至淮滨一线为全省较明显的人口分界线;山区和平原两种地形条件是影响该省人口空间格局的基本因素;在平原地区,区位条件和社会经济发展的互动作用又成为影响城镇人口分布的主要因素。在推进城镇化的进程中,应结合主体功能区划和新型城镇化战略,有序推进城乡人口的再分布。  相似文献   

16.
以广州市中心城区为例,借助百度热力图、百度实时路况和百度地图POI数据,从中观层面多角度综合分析广州市中心城区就业与居住的空间分布关系。结果显示:1)工作时间段人口聚集的高值区整体呈带状分布,斑块较为细碎,但绝大部分集中在核心地带;人口主要高度集中于各区的商业繁华地段与交通线路周围。而休息时间段的高值区则相对集中分布,用地效率较高,表现出多中心的圈层结构;人口主要高度集中分布在传统的老城居住区和新开发的商业住宅区,与核心商圈相对错开。2)不管是在上班时段还是休息时段,人口聚集程度越高的地区,POI设施密度表现越显著;这意味着人口的聚集具有一定的选择性,主要集中在城市基础设施发展较完备的区域。3)广州市中心城区各街道的职住比介于0.73~1.54,职住相对平衡,区域之间差异较小。其中,分值较高的街道多分布于核心地带(主要集中在越秀区、荔湾区北部和天河区南部),分值较低的街道多分布于核心地带的外围或边缘地区(主要在海珠区、荔湾区和白云区零散分布)。4)从城市交通响应上看,广州市中心城区工作日内早高峰的拥堵度大于晚高峰,但总体路况变化跨度不大,区内并没有出现特别严重的“潮汐通勤”现象。  相似文献   

17.
基于GIS的青藏高原人口统计数据空间化   总被引:93,自引:6,他引:87  
根据2000年第5次全国人口普查数据分析,西藏、青海2省区各市县平均人口密度与海拔高度、土地利用、主要道路有较强的相关关系,河流水系对居民点分布的影响较为明显,而居民点是人口分布的重要指示因子。以GIS软件为工具,通过较为客观的方式赋予各影响因子人口分布影响权重,运用多源数据融合技术进行了人口统计数据的空间化。结果显示,通过数据融合产生的人口密度与各市县实际人口密度的相关系数大于0.80,与试验区各乡镇的实际人口密度的相关系数大于0.75。最终生成的栅格人口密度数据既与各市县统计型人口数据保持一致,又反映了各市县内部人口分布的空间变化。  相似文献   

18.
广佛同城化地区人口空间分布演变   总被引:1,自引:0,他引:1  
基于第四、五、六次全国人口普查数据,运用人口密度模型等工具对1990―2010 年广佛都市区的人口空间分布进行了研究。结果发现:广佛都市区人口空间分布可以用单中心人口密度模型进行解释;同城化地区与总体规律相比,同城化进程对边界地区有显著的提升作用,但这种提升具有主体的差异性。广州市没有主动向佛山发展的动力,而次一级的行政区域主体(佛山市)对融入广州市中心的发展则呈现较高的意愿。  相似文献   

19.
张晓瑞  华茜  程志刚 《地理科学》2018,38(11):1809-1816
针对目前城市人口分布研究现状,在传统的空间句法模型基础上,将LBS大数据技术有机引入到城市人口分布研究中,从而构建了理论分布和实际分布有机结合的城市人口分布研究新思路。合肥市中心城区的案例研究显示:空间句法模型与LBS大数据分析所得到的人口集聚区域在空间上并不完全一致;根据空间句法模型和LBS大数据分析结果的综合对比,合肥市中心城区被划分为高密度、中密度和低密度3类人口分区,同时提出了不同密度分区的人口分布发展建议。研究表明,LBS大数据的适时、动态特点能弥补传统数据的不足,其与空间句法模型有机结合将能为城市人口分布研究提供更加精确高效的工具与方法。  相似文献   

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