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1.
This paper quantitatively explores farmers' vulnerability to flood in the Poyang Lake Region (PLR) with the supports of GIS spatial functions. The analysis consists of three major steps, which is based on the spatial unit of township. Firstly, the spatial extent and characteristics of flood risk areas were determined using a digital elevation model (DEM) derived from the 1:50,000 topographic map. Secondly, for each of the township, six indices indicating the economic activities of local farmers were calculated. These indices are: rural population proportion, cultivated land proportion, GDP per unit area, employment proportion of primary industry, net rural income per capita and agricultural income proportion. These six indices were then normalized and used for later vulnerability assessment. Thirdly, the normalized indices (as GIS data layers) were overlaid with the flood risk areas to produce the risk coefficient for each township and to calculate the overall vulnerability for each township. The analysis results show that in the PLR there are high flood risk areas where the farmers' livings are seriously influenced or threatened. About 55.56% of the total 180 townships in the flood risk areas have a high degree of flood vulnerability. The townships under flood risk are mainly distributed in the areas around the Poyang Lake and the areas along the "five rivers".  相似文献   

2.
The damage of dwelling houses constitutes the primary cause of casualties and asset loss in seismic disasters that occurred in Chinese rural areas. The structure of houses is crucial for assessing the vulnerability of rural houses. However, at present, available data on rural housing structure are incomplete and their spatial scales are inconsistent. This paper estimated the amount and ratio of rural houses in five structures, namely ’wood’, ’brick’, ’mixed’, ’reinforced concrete’, and ’other’, for 2380 counties across China. With the percent-age sampling census data in 2005, four accuracy levels were specified. Then, a set of down-scaling models were established, where the impact of climate, economic development level and ethnic minority cultural factors on rural housing structure, as well as the spatial autocorrelation of neighboring spatial units were considered. Based on the estimation results, a database of county-level rural housing structure was established, based on which the vul-nerability of rural houses in different areas was clarified.  相似文献   

3.
Water pollution in the Taihu Lake Basin has been the focus of attention in China and abroad for a long time, due to its position in the forefront of urban development in China. Based on data gathering and processing from 84 monitoring sections in this heavily polluted area, this study first analyzes spatial patterns of urbanization and the distribution of river water pollution, and then uses the GeoDa bivariate spatial autocorrelation model to investigate the spatial correlation between urbanization and river water pollution at the scale of township units. The results show that urbanization has adverse impacts on water pollution, and the influence varies in different levels of development areas. The urban township units have the highest level of urbanization and highest pollution, but the best water quality; the suburban units have lower level of urbanization, but higher pollution and worse water quality; however the rural units have the lowest level of urbanization and lowest pollution, mainly affected by upstream pollution, but worst water quality. Lastly, urban and rural planning committees, while actively promoting the process of development in the region, should gradually resolve the issue of pollution control lagging behind urban life and urban develop- ment, giving priority to construction of centralized sewage treatment facilities and associated pipeline network coverage in the rural areas and suburban areas.  相似文献   

4.
The temporal-spatial geographic distribution of archaeological sites and its feature between 10.0–2.8 ka BP(ka BP= thousands of years before 0 BP, where "0 BP" is defined as the year AD 1950) were determined, based on GIS spatial analysis in the Poyang Lake Basin. The relationship between geographic distribution of sites of different periods under subsistence existence of ancient civilizations, climate and environmental change was investigated. The results revealed numerous archaeological sites of the Neolithic Age(10.0–3.6 ka BP). The sites were mainly located in the northern part of the Poyang Lake Basin, a hilly and mountainous area with many river terraces suitable for the development of human civilization. The number of archaeological sites rapidly increased during the Shang and Zhou dynasties(3.6–2.8 ka BP) and spread widely on the floodplains of the middle and lower reaches of Ganjiang River and onto the west, south, and southeast beach areas of the Poyang Lake. Holocene records of climate change suggested that it was possible that climate fluctuations had a great impact on human evolution in the study area. Before 3.6 ka BP, westward and northward expansion of Neolithic cultures in the Poyang Lake watershed occurred under the background of climate amelioration(becoming warmer and wetter). The ancient people lived in the hilly areas with high elevation. The simple mode of a fishing and gathering economy was mostly suited to this area in the early Neolithic Age. The scope of human activities was expanded and cultural diversity developed in the late Neolithic Age. However, with population growth and increasing survival pressure in a dry-cold climatic stage after 3.6 ka BP, this simple living mode had to be abandoned, and various forms of economy, the majority being agriculture, were developed on flood plains of the lower reaches of numerous rivers around Poyang Lake. This promoted flourishing of the Bronze culture of South China.  相似文献   

5.
Spatial relations,reflecting the complex association between geographical phenomena and environments,are very important in the solution of geographical issues. Different spatial relations can be expressed by indicators which are useful for the analysis of geographical issues. Urbanization,an important geographical issue,is considered in this paper. The spatial relationship indicators concerning urbanization are expressed with a decision table. Thereafter,the spatial relationship indicator rules are extracted based on the application of rough set theory. The extraction process of spatial relationship indicator rules is illustrated with data from the urban and rural areas of Shenzhen and Hong Kong,located in the Pearl River Delta. Land use vector data of 1995 and 2000 are used. The extracted spatial relationship indicator rules of 1995 are used to identify the urban and rural areas in Zhongshan,Zhuhai and Macao. The identification accuracy is approximately 96.3%. Similar procedures are used to extract the spatial relationship indicator rules of 2000 for the urban and rural areas in Zhongshan,Zhuhai and Macao. An identification accuracy of about 83.6% is obtained.  相似文献   

6.
Taking the semi-arid area of Yulin City as an example, this study improves the vulnerability assessment methods and techniques at the county scale using the VSD(Vulnerability Scoping Diagram) assessment framework, integrates the VSD framework and the SERV(Spatially Explicit Resilience-Vulnerability) model, and decomposes the system vulnerability into three dimensions, i.e., exposure, sensitivity and adaptive capacity. Firstly, with the full understanding of the background and exposure risk source of the research area, the vulnerability indexes were screened by the SERV model, and the index system was constructed to assess the characteristics of the local eco-environment. Secondly, with the aid of RS and GIS, this study measured the spatial differentiation and evolution of the social-ecological systems in Yulin City during 2000–2015 and explored intrinsic reasons for the spatial-temporal evolution of vulnerability. The results are as follows:(1) The spatial pattern of Yulin City's SESs vulnerability is "high in northwest and southeast and low along the Great Wall". Although the degree of system vulnerability decreased significantly during the study period and the system development trend improved, there is a sharp spatial difference between the system vulnerability and exposure risk.(2) The evolution of system vulnerability is influenced by the risk factors of exposure, and the regional vulnerability and the spatial heterogeneity of exposure risk are affected by the social sensitivity, economic adaptive capacity and other factors. Finally, according to the uncertainty of decision makers, the future scenarios of regional vulnerability are simulated under different decision risks by taking advantage of the OWA multi-criteria algorithm, and the vulnerability of the regional system under different development directions was predicted based on the decision makers' rational risk interval.  相似文献   

7.
Assessment of population carrying capacity is a key task in the reconstruction planning of areas struck by disasters, in which the precision of estimation is required. This study developed a decision-making model for estimating the population capacity of the involved townships and cities in the 2008 Wenchuan Earthquake based on the assessment of the suitability for reconstruction of the areas. Through analysis, arable land resources were argued to be the critical constraint of population capacity in these areas. Then, the spatial differentiations of the post-quake development conditions across different regions were analyzed with respect to their natural environments, socio-economic development and quake damages. The expected levels of urbanization, family incomes and income structures, output levels of land, and the reliance of agricultural population on arable land were estimated by different regions. With these parameters, the population capacities of the involved townships and cities in three scenarios were estimated. The total population capacity of the entire areas is abundant compared with the actual post-quake population; however, the status of over-population substantially varies across space. It was suggested to put the emphasis of post-quake resettlement policy on those counties where earthquake had been the main causes of over-population. In the Full Recovery Scenario, three mountain counties were identified including Wenchuan, Beichuan and Maoxian, with a total over-population of about 100,000 people.  相似文献   

8.
Seasonal water-level fluctuations(WLF) play a dominate role in lacustrine ecosystems. River-lake interaction is a direct factor in changes of seasonal lake WLF, especially for those lakes naturally connected to upstream and downstream rivers. During the past decade, the modification of WLF in the Poyang Lake(the largest freshwater lake in China) has caused intensified flood and irrigation crises, reduced water availability, compromised water quality and extensive degradation of the lake ecosystem. There has been a conjecture as to whether the modification was caused by its interactions with Yangtze River. In this study, we investigated the variations of seasonal WLF in China’s Poyang Lake by comparing the water levels during the four distinct seasons(the dry season, the rising season, the flood season, and the retreating season) before and after 2003 when the Three Gorge Dam operated. The Water Surface Slope(WSS) was used as a representative parameter to measure the changes in river-lake interaction and its impacts on seasonal WLF. The results showed that the magnitude of seasonal WLF has changed considerably since 2003; the seasonal WLF of the Poyang Lake have been significantly altered by the fact that the water levels both rise and retreat earlier in the season and lowered water levels in general. The fluctuations of river-lake interactions, in particular the changes during the retreating season, are mainly responsible for these variations in magnitude of seasonal WLF. This study demonstrates that WSS is a representative parameter to denote river-lake interactions, and the results indicate that more emphasis should be placed on the decrease of the Poyang Lake caused by the lowered water levels of the Yangtze River, especially in the retreating season.  相似文献   

9.
Urban-rural integration (URI) is a new idea to guide the urban-rural transformation in China, and exploring the spatio-temporal characteristics and driving mechanism of URI in China is an urgent need to overcome the dilemmas of insufficient rural development and unbalanced urban and rural development. Based on the process framework of "foundation-motivation-result" of URI, an evaluation indicator system was constructed. The improved entropy evaluation model and the kernel density estimation method were used to quantitatively measure the spatiotemporal evolution characteristics of URI level of 31 provinces, autonomous regions, and municipalities in China's mainland from 2000 to 2020. This study further used the Geodetector to explore the heterogeneous evolution of driving factors for URI level in different regions of China. The main conclusions are as follows: 1) From 2000 to 2020, the URI level in China decreased first and then increased, showing a √-shaped trend, and its spatial differences narrowed. 2) The URI level in China presented a spatial pattern of high in the east and low in the west, divided by the Hu Huanyong Line. The high-value centers showed prominent polarization characteristics and presented a zonal aggregation trend. The medium-value areas were clustered but weakened,and showed a spreading trend from the eastern to the central and western parts. 3) At the national scale, the core influencing factors of URI level were population mobility, economic development level, urban-rural income gap, and educational supports, potential factors were the optimization of industrial structure and the opening-up level, and threshold effect existed in investment benefit and government intervention. At the regional scale, the core driving forces of URI level in China showed obvious spatial heterogeneity, and in 2020 they were economic development level, investment benefit, and government intervention in the eastern region, investment benefit, opening-up level, and urban-rural income gap in the central region, are educational supports, government intervention, and the optimization of industrial structure in the western region. The interaction of driving factors had far more influence on URI level in China than individual factors, and the interaction between traffic accessibility and other socioeconomic factors had been significantly enhanced. Research on the spatio-temporal evolution and mechanism of URI in China can provide theoretical basis for rural revitalization and high-quality urban and rural development. © 2023, Editorial office of PROGRESS IN GEOGRAPHY. All rights reserved.  相似文献   

10.
Dai  Erfu  Wang  Yahui 《地理学报(英文版)》2020,30(6):1005-1020
Ecosystem services, which include water yield services, have been incorporated into decision processes of regional land use planning and sustainable development. Spatial pattern characteristics and identification of factors that influence water yield are the basis for decision making. However, there are limited studies on the driving mechanisms that affect the spatial heterogeneity of ecosystem services. In this study, we used the Hengduan Mountain region in southwest China, with obvious spatial heterogeneity, as the research site. The water yield module in the In VEST software was used to simulate the spatial distribution of water yield. Also, quantitative attribution analysis was conducted for various geomorphological and climatic zones in the Hengduan Mountain region by using the geographical detector method. Influencing factors, such as climate, topography, soil, vegetation type, and land use type and pattern, were taken into consideration for this analysis. Four key findings were obtained. First, water yield spatial heterogeneity is influenced most by climate-related factors, where precipitation and evapotranspiration are the dominant factors. Second, the relative importance of each impact factor to the water yield heterogeneity differs significantly by geomorphological and climatic zones. In flat areas, the influence of evapotranspiration is higher than that of precipitation. As relief increases, the importance of precipitation increases and eventually, it becomes the most influential factor. Evapotranspiration is the most influential factor in a plateau climate zone, while in the mid-subtropical zone, precipitation is the main controlling factor. Third, land use type is also an important driving force in flat areas. Thus, more attention should be paid to urbanization and land use planning, which involves land use changes, to mitigate the impact on water yield spatial pattern. The fourth finding was that a risk detector showed that Primarosol and Anthropogenic soil areas, shrub areas, and areas with slope 5° and 25°–35° should be recognized as water yield important zones, while the corresponding elevation values are different among different geomorphological and climatic zones. Therefore, the spatial heterogeneity and influencing factors in different zones should be fully con-sidered while planning the maintenance and protection of water yield services in the Hengduan Mountain region.  相似文献   

11.
This paper quantitatively explores farmers’ vulnerability to flood in the Poyang Lake Region (PLR) with the supports of GIS spatial functions. The analysis consists of three major steps, which is based on the spatial unit of township. Firstly, the spatial extent and charac-teristics of flood risk areas were determined using a digital elevation model (DEM) derived from the 1:50,000 topographic map. Secondly, for each of the township, six indices indicating the economic activities of local farmers were calculated. These indices are: rural population proportion, cultivated land proportion, GDP per unit area, employment proportion of primary industry, net rural income per capita and agricultural income proportion. These six indices were then normalized and used for later vulnerability assessment. Thirdly, the normalized indices (as GIS data layers) were overlaid with the flood risk areas to produce the risk coeffi-cient for each township and to calculate the overall vulnerability for each township. The analysis results show that in the PLR there are high flood risk areas where the farmers’ livings are seriously influenced or threatened. About 55.56% of the total 180 townships in the flood risk areas have a high degree of flood vulnerability. The townships under flood risk are mainly distributed in the areas around the Poyang Lake and the areas along the “five rivers”.  相似文献   

12.
鄱阳湖区洪灾风险与农户脆弱性分析   总被引:13,自引:0,他引:13  
马定国  刘影  陈洁  郑林  张文江 《地理学报》2007,62(3):321-332
运用1:5 万DEM 地形数据对鄱阳湖区洪涝灾害风险区区域范围及空间分布进行了分析。在此基础上, 以乡镇为基本研究单元, 选取乡村人口比重、耕地面积比重为洪灾风险暴露分析指标, 选取单位面积生产总值、农民人均纯收入、第一产业从业人员比重、农业收入占农村经济总收入比重等为农户洪灾应对能力分析指标, 并引入了不同洪水水位特征值的影响系数, 对鄱阳湖区农户洪灾脆弱性程度进行了定量研究。结果表明, 鄱阳湖洪灾风险区面积广、影响深, 农户对洪涝灾害总体上存在着较高的脆弱性; 在所涉及的180 个乡镇中, 农户脆弱度高于平均值的有100 个, 占到乡镇数55.56%。脆弱度最高的乡镇主要集中在滨湖地带及五河干流沿岸地区, 而脆弱度较低的乡镇则主要分布在湖区各县城关镇所在区域。  相似文献   

13.
基于栅格的鄱阳湖生态经济区洪灾脆弱性评价   总被引:2,自引:1,他引:1  
目前洪灾脆弱性研究主要是基于行政区划上的社会脆弱性评价,无法揭示评价单元内部脆弱性的空间分布。选取鄱阳湖生态经济区作为研究对象,根据人与环境系统的特点,选择影响洪灾脆弱性的15个变量,建立了基于栅格的洪灾脆弱性综合指数模型。结果表明,研究区域的洪灾脆弱性以中度脆弱为主,极度与高度脆弱区主要分布在人口密集的鄱阳湖东南与西南部的湖滨地区、主要河流的缓冲区以及土地利用类型为水田的区域。从脆弱性的3个要素(暴露度、敏感性和适应能力)的空间分布揭示了洪灾脆弱性空间分布形成的原因。基于栅格的评价结果,能够充分反映县市内部和行政边界处洪灾脆弱性的空间分布与变化情况。  相似文献   

14.
Less developed places that are affected by climatic impacts face great challenges to future development. Place-based assessments that look at both the development level and climatic impacts on development are important for understanding the current state of human well-being and generating insights into how to facilitate sustainable development in the future. We carry out an assessment of human well-being in the Poyang Lake Region of China (PLR), using GIS, remote sensing, and socio-economic data. We measure human well-being in three aspects of (i) development level, (ii) exposure of development to flooding, and (iii) sensitivity of development to flooding. Following the United Nations Development Programme's human development index, we examine development through measures of life expectancy, literacy, and income. We first use a digital elevation model and GIS data on levees to map flood hazard in PLR. Based on the flood hazard map, we then derive quantitative measures of exposure and sensitivity of the development in a town to flooding. Our assessment indicates that development in PLR overall is highly exposed and sensitive to flooding. There are significant variations in different aspects of human well-being among the 298 towns in the region. These variations suggest different sustainable development pathways and policy interventions for different places. We discuss the potential usefulness of our approach for other similar places.  相似文献   

15.
环鄱阳湖区农家菜地土壤重金属风险评价及来源分析   总被引:4,自引:0,他引:4  
通过评价环鄱阳湖区10个县农家菜地土壤样品重金属的潜在生态风险,分析其与9个社会经济指标间的灰色关联度来探讨重金属的污染来源。结果显示,鄱阳湖区各菜地土壤中Cd的超标情况最严重,超标率达到90%,除部分地区Cu超标外,其余重金属均未超标。鄱阳湖区农家菜地土壤达到轻微生态风险,工业较发达地区重金属生态风险较大于工业落后地区,工业发展情况对湖区的空间污染分异有较大影响。蔬菜产量、工业发展情况、城镇化率、交通业发展情况和菜地土壤不同种重金属具有较高关联度,而地区生产总值、农药使用量对各种重金属含量的影响最弱。  相似文献   

16.
村镇建设类型划分的理论与方法研究——以江苏省为例   总被引:1,自引:0,他引:1  
村镇地区是多要素组合的地域单元,由于区位条件复杂多样,资源禀赋差异明显,村镇建设具有多元发展路径。基于资源环境承载力视角,构建了“压力-状态-响应”框架下的村镇建设分类指标体系,采用单向优势指标和复合指标相对优势判断相结合的划定方法,综合考虑国家和省级功能区划、协调乡镇周边区域功能并衔接省国土空间发展战略,以乡镇为分析单元,建立了省级村镇建设分类综合方案,并以江苏省为案例进行村镇建设类型划分研究。研究结果发现,江苏省仅有29.61%的乡镇为明显的单一建设类型,村镇建设的综合性发展态势明显;村镇建设类型具有明显的地域差异,苏北地区主要以居住类乡镇和生态类乡镇为主,苏中地区种植类乡镇和养殖类乡镇居多,苏南地区则集聚了商旅类和工业类乡镇。以此为基础提出不同村镇建设类型的资源环境承载力提升策略。  相似文献   

17.
在推导中国水果产业布局演变的影响模型基础上,以1985—2019年中国22个水果主产省为研究对象,探讨农业劳动价格、非农劳动价格和工资收入占比对我国水果产业布局演变的影响效应。结果表明:农业劳动价格、非农劳动价格和工资收入占比的提高对东部水果种植产生替代效应,造成东部各省区水果种植面积减少或增幅不明显,比重下降;农业劳动价格、非农劳动价格和工资收入占比对中部水果种植的影响具有省际异质性,产生的替代效应和收入效应相互抵消,导致中部整体水果种植比重无显著变化;西北、西南地区较低的农业劳动工价和非农劳动价格使其具有劳动成本比较优势,工资收入占比提高产生收入效应,使西北、西南地区水果种植面积大幅增加,比重上升,促成我国水果种植布局“西移内扩”。因此,优化水果产业布局要解决水果适宜区农村劳动力价格过高和非适宜区农村劳动力价格过低等问题。  相似文献   

18.
退耕还林(草)政策的实施有效改善了陇中黄土丘陵区小流域生态环境、抑制了严重的水土流失,然而,对该区退耕还林(草)政策的实施和交通便利程度对小流域农户收入结构的耦合影响及互馈作用机制尚不清楚。本文选取定西市安定区巉口镇龙滩小流域为研究区,通过问卷调查获取3个区120个农户家庭土地利用情况、经营方式及收入数据,运用方差分析、回归分析和通径分析等方法定量分析交通便利程度和退耕还林比例对农户收入的影响与调控作用。结果表明:退耕还林比例影响了农田面积,进而影响了玉米和马铃薯的种植面积,由此增加了种植业收入,从而导致3个区低比例退耕还林农户收入均高于高比例退耕还林农户收入。同时退耕面积的增加也促使劳动力向非农产业的转移,而交通便利程度影响农户家庭打工人口比例,从而导致Ⅰ(交通便利)区农户的收入显著高于Ⅱ(交通欠发达)和Ⅲ(交通闭塞)区。交通便利程度和退耕还林比例通过农田面积、退耕还林地面积、玉米和马铃薯种植面积及打工人数等影响种植业、劳务输出和退耕还林政策性补助,进而影响流域内农户的收入水平。总之,退耕还林(草)政策的实施影响了陇中黄土丘陵区种植业和劳务输出产业的发展且存在区域差异,而对该区养殖业、林业及副业带动有限。因而,在新一轮退耕还林(草)政策实施之际,该区在加强交通等乡村基础条件建设的同时还需推动林下经济、特色养殖及副业发展,降低农户对种植业和退耕还林政策性补助的依赖,以此实现陇中黄土丘陵区生态和经济的可持续发展,提升农村绿色生产力。  相似文献   

19.
城市山洪灾害风险评价——以云南省文山县城为例   总被引:1,自引:1,他引:1  
朱静 《地理研究》2010,29(4):655-664
山洪灾害风险评价对于减灾防灾决策和管理非常重要。本文介绍基于遥感和GIS方法的应用,探讨一种快速、简便而且较为准确的城市山洪灾害风险评价方法。以发生于1998年7月26日文山城20年一遇山洪灾害为实例,将GIS的数字高程模型与实测的山洪水位和洪峰流量结合进行淹没分析,研究表明采用该方法可以模拟准确山洪泛滥范围,并计算淹没水深分布。根据不同水深指标,应用GIS工具完成了山洪灾害危险分区。本研究利用高分辨率遥感影像提供承灾体类型的可靠和准确数据用于易损性分析和期望损失评估的价值计算。根据典型区财产损失的抽样调查,建立了不同承灾体类型与水深的关系,并确定其损失率;应用GIS空间数据处理和分析的集成方法完成了复杂的损失评估。在此基础上,按期望损失程度进行分区划分而完成山洪风险评价。研究结果表明基于GIS和RS方法进行山洪风险评价效果良好,值得推广应用于其他洪水泛滥区。  相似文献   

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