基于长时间尺度下滑坡易发性评价研究———以甘肃省永靖县为例

利用决策树模型,基于五期土地利用评价因子,对甘肃省永靖县进行近40年的长时间尺度下的滑坡易发性评价,五期评价结果均显示研究区内滑坡灾害的极高和高易发性区域主要集中在中部黄河流域(盐锅峡镇至刘家峡水电站段)周边、西南部川城村—红泉镇—王台乡周边区域以及中部偏东的三条岘乡,该区域人口密集,人类活动较多.研究结果与前人研究结果类似,且通过受试者工作特征曲线的精度检验,说明五期评价结果均具有较高的可靠性.另外,研究区内的自然植被和裸土地与滑坡易发性指标之间具有负相关关系,而旱地、水域和城乡建设用地等人类活动频繁的区域则更容易导致滑坡灾害的发生.从时间尺度上来看,极高和高易发性分区面积逐年下降,但自 2000年,极高和高易发性分区面积减少速度出现显著减缓,同期,该区域内的土地利用变化为城乡建设用地面积增加而植被面积减少,这使得区域内边坡稳定性下降,使部分防灾工程措施的减灾能力下降.本研究为该地区的灾害预防、预测和城乡土地规划提供了参考.     

Multi-agent based modeling of spatiotemporal dynamical urban growth in developing countries: simulating future scenarios of Lianyungang city,China

Urbanization is the most typical form of land use/cover change, and exploration of the driving mechanism of urban growth and the prediction of its future changes are very important for achieving urban sustainable development. In view of the ability of a multi-agent system to simulate a complex spatial system and from the perspective of combining macroscopic and microscopic decision-making behaviors of agents, a spatiotemporal dynamical urban growth simulation model based on the multi-agent systems has been developed. In this model, macroscopic land use planning behaviors implemented by macroagents and microscopic land use selection behaviors autonomously generated by microagents interact within two-dimensional spatial cells. Furthermore, the urbanization process is promoted through joint decision-making by macroagents and microagents. Considering the central region of the coastal industrial city Lianyungang as the study area, we developed three target scenarios on the basis of current trends, economic development priorities, and environmental protection priorities. Moreover, the corresponding urban growth scenarios were simulated and analyzed. The simulation results show that by combining the macroscopic and microscopic decision-making behaviors of agents to simulate spatiotemporal dynamical urban growth based on the multi-agent systems, the proposed model can provide a useful spatial exploratory tool for explaining the driving mechanism of urbanization and providing decision-making support for urban management.     

Expansion of Ürümqi urban area and its spatial differentiation

The expanded area and structure of urban lands and landscape features in Ürümqi City are analyzed using RS and GIS means based on the MSS image in 1975 and the TM images in 1990, 1999 and 2002, as well as other related maps. On which the scale, intensity and spatial differentiation of the expansion of the Ürümqi urban area during different periods are lucubrated. The results reveal that urban expansion was rapid during the periods of 1949–1965 and 1975–1990, and that it was stable after the 1990s. The urban expansion pattern was significantly different during different time periods: the urban area was expanded outwards based on old districts in a spanned development pattern during the period of 1949–1965; development was stagnant during the period of 1965–1975; urban expansion developed mainly in old districts in a grouped way during the period of 1975–1990. The trend of urban expansion along the traffic lines was obvious, and the direction of urban expansion was dominated by the south-north zonal expansion and supplemented by east-west axial expansion; urban expansion reached the development stage of “multiple centers and multiple districts” after the 1990s, and urban networks were developed more precisely after this time. The sources for urban expansion were mainly cultivated lands, grasslands and unused lands; during urban expansion, the land area devoted to traffic lines, residential areas, dispersive industrial and mineral areas, and garden plots was rapidly enlarged.     

博斯腾湖最低生态水位计算

随着城市化和工业化进程加快,无锡等太湖周边城市的土地利用方式发生了巨大变化,特别是建设用地蔓延,侵占了湖滨带生态保护区,使湖泊生态系统的功能和健康受到威胁,太湖水体污染严重.以生态-经济为导向的土地开发适宜性分区,就是通过对不同地区的土地开发方式和强度的管制,使土地利用的空间结构与健康太湖的保护目标相适应.这样的分区强调因地制宜地将评价区域划分为不同开发强度类型的地区,鼓励资源环境容量大的地区承担高强度的社会经济活动,同时限制生态敏感区域的开发强度.论文在借鉴已有区划方法的基础上,讨论了评价单元的划分、评价指标选择与处理等技术方法,并以无锡市为例,将其划分为优先开发区域、适度开发区域、控制开发区域、适度保护区域以及绝对保护区域等五大类型区,提出各类型分区管制的相应政策保障.     

南四湖流域1980-2015年土地利用变化及其对流域生境质量的影响

生境质量在一定程度上决定了区域生物多样性维持能力的高低,评估区域生境质量对土地利用/覆被变化的响应,可以间接衡量区域生物多样性维持功能的时空变化,为生物多样性保护提供定量参考.本文以南四湖流域为例,运用InVEST-Habitat Quality模型模拟评价1980-2015年流域生境质量的时空变化,定量评估湖区退耕还湿还林和丘陵地区退耕还林2种政策情景对区域生境质量改善的效果.结果表明：35 a间流域耕地、林地和草地大量转化为建设用地,城市建设用地增长40.23%,湖泊面积减少35.56%,主要转化为渔业坑塘;南四湖流域整体生境质量处于较低水平,近35 a来快速发展的工农业生产和不断扩张的城市用地使得流域生境质量呈现降低趋势,当前平均生境质量为历年最低（0.20）.环境保护力度和人类活动剧烈程度的差异导致生境质量在空间上呈现出西部平原区（0.19） < 东部丘陵山区（0.44） < 南四湖湖区（0.81）的分布特征.近35 a来生境稀有度（即生境保存完整性指数）较高的区域主要是湖区主体和流域东部丘陵山区,但部分边缘湖区生境稀有度指数却极低,受人类活动干扰剧烈,主要原因在于沿湖渔业养殖和农业活动.定量评估湖区退耕还林还湿和流域丘陵旱地退耕还林2种政策情景对生境质量的改善效果,结果表明湖区退耕还湿还林能使湖区生境质量上升9.21%,而丘陵旱地退耕还林可使流域平均生境质量提高16.75%.     

A method of urban ecological risk assessment: combining the multimedia fugacity model and GIS

Industrial pollution has caused serious human health risk because the pollutants can be accumulated in human body via multi routes in a long term, especially in areas of rapid industrialization. It is of great importance to obtain the pollutants’ information, including the transport routes and spatial distribution in the various environmental media of different sub-regions, to facilitate more accurate risk assessment and more effective risk management in urban ecosystems. In this article, we proposed a research framework of urban ecological risk assessment method, which combines the multimedia fugacity model, the multi-route exposure model, exposure-risk relationships and geographic information system (GIS). An urban ecological risk assessment of a hypothetical region indicates that it is possible and feasible to introduce GIS into the previous method to satisfy the requirements of risk management. The assessment results can be further utilized for industrial pollution emission control.     

Economic development,urban expansion,and sustainable development in Shanghai

Studies of urbanization effects in Chinese cities from the aspect of the coupled development of economy and environment are rare due to data limitations. This paper studied Shanghai’s fast urban expansion and examined the dynamic relationship between economic growth and environment consequences at the district level. We extracted data on urban built-up area and land surface temperature from remote sensing images. We analyzed the patterns of urban expansion and land use change and explained the dynamic relationship between economic development and environment conditions. We attributed the uneven economic development and environmental change in districts of Shanghai to four main institutional factors: (1) the role of the government, (2) the multi-level urban planning system, (3) land market reform, and (4) the economic restructuring.     

太湖流域空间开发适宜性分区与失衡性评估

随着发达地区经济社会的快速发展,建设用地急剧扩张,改变地表下垫面水文条件,成为导致区域水环境不断恶化的重要因素,并引发一系列的资源环境问题.为了促进资源环境与经济社会均衡发展,近年来地理学界开展了大量空间开发功能分区和适宜性分区的研究,为区域空间管理和建设用地调控提供科学依据,但是这些研究大多以单一行政区为对象,缺少流域等跨行政区的自然地理单元的分区研究,忽视了流域经济社会发展与资源环境保护的整体性.为此,本文在借鉴相关分区研究的基础上,以太湖流域为例,探讨了流域单元空间开发适宜性分区指标选择与综合评价等技术方法,将太湖流域划分为高适宜区、中等适宜区、低适宜区和不适宜区等四种类型,并采用数据包络分析方法,探讨了建设用地配置规模与空间开发适宜性的对应关系和均衡程度,据此判断流域空间开发的失衡状态.     

城市化对水系结构及其连通性的影响——以秦淮河中、下游为例

针对当前城市化所引起水系衰减、河流连通受阻以及由此所引起洪涝与水环境的问题,以秦淮河中、下游为例,选取1979和2006年两期流域遥感影像,分析了城市化影响下的下垫面变化特征;选取1980s和2009年的地形图对河流水系进行提取,借鉴景观生态学中河流廊道空间结构分析方法,通过不同时期水系分级,探讨了城市化对水系结构及其连通性的影响.结果表明:(1)城市化使得2006年城镇用地面积相比1979年增加84.54 km²,增加了9倍多,大量林草地、耕地以及水域转变成城镇用地;(2)河流长度在过去的30年里减少了41%,河道主干化趋势明显;河流发育呈现由多元到单一、由复杂到简单的趋势;(3)连通性参数连接率、实际结合度分别由原来的1.28、0.43下降到0.79、0.26,河流的连通性呈下降趋势.该研究将为城市化地区河流水系保护提供支持与参考.     

Study on spatial pattern of land-use change in China during 1995—2000

Land-use/cover change has become an event being of paramount importance to the study of global environmental change[1,2]. Land-cover change is closely related to the terrestrial surface material cycles and life-support processes[3], i.e., the interaction …     

汶川8.0级地震北川县城震害原因分析

汶川MS8.0地震中,处于映秀—北川断裂带上的北川县城区地震烈度达Ⅺ度。地震断层活动在地表形成了3条破裂带,城区地表破裂带占总面积的比例超过6.5%,使建筑物遭受严重破坏,并引发了滑坡与崩塌灾害,加剧了震害损失。各种成灾机制之间存在相互耦合现象,不良地质现象发育是导致北川县城区震害程度极为严重的主要原因。     

Sensitivity of bocage landscapes to surfaces run-off: Application of the kirkby index

The Breton bocage is a landscape of fields enclosed by a network of hedgerow banks and ditches. Organization of this bocage varies considerably in different areas of Brittany. However, one constant feature of the different bocage landscapes is the presence of banks enclosing bottom lands, which enclose elongated plots in the thalweg bottoms. The banks enclosing the bottom lands influence the sensitivity of the basin to surface run-off and also the presence of excess surface water zones. To analyse the part played by banks enclosing bottom lands, the topography of a typical first order basin was modelled and the existence of such a bank within the catchment was simulated. The effect of the bank on the Kirkby index, a topographical parameter defining the sensitivity of soils to surface run-off was analysed. Modification of its spatial distribution is considerable for mean values of the index. The saturation zone, the storm run-off source area, is reduced to that area of bottom land enclosed by the bank; it thus varies very little so that run-off conditions are almost constant whatever the climatic conditions. From the methodological point of view, the interest of analysing the spatial distribution of morphometric parameters of a catchment may be noted; in the example studied, the heterogeneity of the Kirkby index distribution is an important factor in the analysis.     

Remote sensing-based artificial surface cover classification in Asia and spatial pattern analysis

Artificial surfaces, characterized with intensive land-use changes and complex landscape structures, are important indicators of human impacts on terrestrial ecosystems. Without high-resolution land-cover data at continental scale, it is hard to evaluate the impacts of urbanization on regional climate, ecosystem processes and global environment. This study constructed a hierarchical classification system for artificial surfaces, promoted a remote sensing method to retrieve subpixel components of artificial surfaces from 30-m resolution satellite imageries(Globe Land30) and developed a series of data products of high-precision urban built-up areas including impervious surface and vegetation cover in Asia in 2010. Our assessment, based on multisource data and expert knowledge, showed that the overall accuracy of classification was 90.79%. The mean relative error for the impervious surface components of cities was 0.87. The local error of the extracted information was closely related to the heterogeneity of urban buildings and vegetation in different climate zones. According to our results, the urban built-up area was 18.18×104 km2, accounting for 0.59% of the total land surface areas in Asia; urban impervious surfaces were 11.65×104 km2, accounting for 64.09% of the total urban built-up area in Asia. Vegetation and bare soils accounted for 34.56% of the urban built-up areas. There were three gradients: a concentrated distribution, a scattered distribution and an indeterminate distribution from east to west in terms of spatial pattern of urban impervious surfaces. China, India and Japan ranked as the top three countries with the largest impervious surface areas, which respectively accounted for 32.77%, 16.10% and 11.93% of the urban impervious surface area of Asia. We found the proportions of impervious surface and vegetation cover within urban built-up areas were closely related to the economic development degree of the country and regional climate environment. Built-up areas in developed countries had relatively low impervious surface and high public green vegetation cover, with 50–60% urban impervious surfaces in Japan, South Korea and Singapore. In comparison, the proportion of urban impervious surfaces in developing countries is approaching or exceeding 80% in Asia. In general, the composition and spatial patterns of built-up areas reflected population aggregation and economic development level as well as their impacts on the health of the environment in the sub-watershed.     

改革开放以来太湖流域工业企业布局演变

太湖流域快速工业化进程加剧了对该地区资源环境的扰动,不合理的工业布局是其重要原因.本文采用经济普查企业点位分布数据,运用空间分析与有序Probit模型等方法,定量分析改革开放以来,太湖流域工业企业空间分布的格局演变及其区位选择的驱动机理,并重点考察太湖环境保护对企业区位行为的影响.结果表明,在2007年太湖水危机事件以前,上海以及太湖北部的苏锡常地区一直是该流域工业企业的主要集聚区域,但随着时间的推移呈现分散化趋势,尤其以内资为主的小型污染企业呈现向宜兴等流域上游地区扩散是导致水危机暴发的一个重要原因.而工业企业环境保护意识淡薄和地方环境监管缺位是造成企业不合理分布的重要因素.     

Study on spatial pattern of land-use change in China during 1995–2000

It is more and more acknowledged that land-use/cover dynamic change has become a key subject urgently to be dealt with in the study of global environmental change. Supported by the Landsat TM digital images, spatial patterns and temporal variation of land-use change during 1995 –2000 are studied in the paper. According to the land-use dynamic degree model, supported by the 1km GRID data of land-use change and the comprehensive characters of physical, economic and social features, a dynamic regionalization of land-use change is designed to disclose the spatial pattern of land-use change processes. Generally speaking, in the traditional agricultural zones, e.g., Huang-Huai-Hai Plains, Yangtze River Delta and Sichuan Basin, the built-up and residential areas occupy a great proportion of arable land, and in the interlock area of farming and pasturing of northern China and the oases agricultural zones, the reclamation of arable land is conspicuously driven by changes of production conditions, economic benefits and climatic conditions. The implementation of “returning arable land into woodland or grassland” policies has won initial success in some areas, but it is too early to say that the trend of deforestation has been effectively reversed across China. In this paper, the division of dynamic regionalization of land-use change is designed, for the sake of revealing the temporal and spatial features of land-use change and laying the foundation for the study of regional scale land-use changes. Moreover, an integrated study, including studies of spatial pattern and temporal process of land-use change, is carried out in this paper, which is an interesting try on the comparative studies of spatial pattern on change process and the change process of spatial pattern of land-use change.     

白洋淀湿地表层土壤主要环境元素分布特征及来源

白洋淀是雄安新区生态共同体的重要组成部分,在"白洋淀生态环境治理和保护规划"中,淀区内纯水村和耕地将被淹没,而上述陆地的土壤环境元素分布特征及来源仍缺乏系统调查和分析.本文以淀区内现有0～ 20 cm土壤为研究对象,以环境元素As、Hg、Cd、Cr、Pb、Ni、Cu、Zn、N、P和土壤类型、质地为研究要素,以统计描述、方差分析、相关分析和因子分析为研究手段对淀区内土壤主要环境元素分布特征和来源进行刻画和分析.结果 表明:淀区主要环境元素在不同土地类型的差异性分布是大气沉降和人类工农业活动综合作用的结果.除元素P外,其余环境元素的淀区背景值均高于区域背景值,呈富集趋势.大部分元素趋向于在农用地富集,在水田的富集最为突出,Hg元素则更易在村镇用地富集.淀区内土壤主要环境元素来源分3种类型:大气沉降型,代表元素为Ni、Cr、As、Pb、Cu和Cd,主要来自区域燃煤烟气的沉降输入;农业输入型,代表元素为P、N、Hg、Cd、Pb,主要来自本地农业施肥和人类生活垃圾输入;工业叠加型,代表元素为Zn、Cu、Cd、Pb,主要来自大气沉降和淀区临近的小冶炼的排放叠加,其中Pb、Cd、Cu为综合输入方式.     

新疆艾比湖湿地土地荒漠化动态监测研究

新疆艾比湖湿地是准噶尔盆地西南缘最低洼地和水盐汇集中心,在我国内陆荒漠自然生态系统中具有典型性和较高的保护价值.本次研究通过对不同时相的多源卫星数据进行配准与复合分类处理,结合野外调研,解译分析各类荒漠化土地类型的时空分布特征.研究结果表明;艾比湖地区的荒漠化以土地盐渍化和风蚀两大类型占绝对优势,其动态变化特点是风蚀减少盐渍化增加.2000—2002年风蚀荒漠化的面积减少了403.06162km2,减少幅度达53%.盐渍化面积增加了183.7km2,比重由54%上升为70%.就荒漠化的程度而言目前是趋于下降.很多重度风蚀及盐渍化转为了中度,复合型荒漠化面积增加.     

An EcoCity model for regulating urban land cover structure and thermal environment: Taking Beijing as an example

Urban land-use/cover changes and their effects on the eco-environment have long been an active research topic in the urbanization field. However, the characteristics of urban inner spatial heterogeneity and its quantitative relationship with thermal environment are still poorly understood, resulting in ineffective application in urban ecological planning and management.Through the integration of "spatial structure theory" in urban geography and "surface energy balance" in urban climatology, we proposed a new concept of urban surface structure and thermal environment regulation to reveal the mechanism between urban spatial structure and surface thermal environment. We developed the EcoCity model for regulating urban land cover structure and thermal environment, and established the eco-regulation thresholds of urban surface thermal environments. Based on the comprehensive analysis of experimental observation, remotely sensed and meteorological data, we examined the spatial patterns of urban habitation, industrial, infrastructure service, and ecological spaces. We examined the impacts of internal land-cover components(e.g., urban impervious surfaces, greenness, and water) on surface radiation and heat flux. This research indicated that difference of thermal environments among urban functional areas is closely related to the proportions of the land-cover components.The highly dense impervious surface areas in commercial and residential zones significantly increased land surface temperature through increasing sensible heat flux, while greenness and water decrease land surface temperature through increasing latent heat flux. We also found that different functional zones due to various proportions of green spaces have various heat dissipation roles and ecological thresholds. Urban greening projects in highly dense impervious surfaces areas such as commercial, transportation, and residential zones are especially effective in promoting latent heat dissipation efficiency of vegetation, leading to strongly cooling effect of unit vegetation coverage. This research indicates that the EcoCity model provides the fundamentals to understand the coupled mechanism between urban land use structure and surface flux and the analysis of their spatiotemporal characteristics. This model provides a general computational model system for defining urban heat island mitigation, the greening ratio indexes, and their regulating thresholds for different functional zones.     

Sustainable sanitation systems for low income urban areas – A case of the city of Bulawayo,Zimbabwe

Lack of basic sanitation systems threaten environmental and human health in low income urban communities. In 2005, the Government of Zimbabwe carried out a cleanup exercise in urban areas involving the destruction of illegal structures which left many people homeless. As a solution to this problem, the government embarked on an extensive housing construction exercise on unserviced land; the ‘Garikai/Hlalani Kuhle’ development programme. The objective of this paper was to investigate the sanitation status in one such area (Cowdray Park Extension, Bulawayo) and determine a sustainable sanitation system for the improved collection of wastewater from the unserviced low income urban area. The study was carried out between October 2010 and February 2011. The sanitation status as well as the residents’ preferences for improved sanitation and the economic set up of the community for the study area was determined through use of questionnaires to the residents. The local authority was then consulted to recommend sanitation facilities and system for the area that met regulatory requirements. A literature study identified sanitation options that were applicable to low income and high density urban areas. The baseline survey found that 61% of the people in the study area lacked sanitation facilities and practiced open defecation. The majority of the residents (70%) preferred ‘flush and discharge’ system sanitation facilities, which was in line with the local council’s requirements. On-site sanitation options were found not to be feasible as per the council regulations and the findings of the literature study, for areas with a high density of houses. Therefore a sewerage system was designed using the conventional sewerage design approach as well as the simplified sewerage design approach in order to determine the collection system that would best meet the needs of the community. In conclusion, the community was in dire need of a sanitation system and a waterborne offsite sanitation system was found to be a feasible option. The simplified sewerage system was found to deliver the same hydraulic benefits for collecting wastewater as the conventional but was 33% cheaper to construct and hence more affordable for the community. It was recommended that stringent environmental monitoring of the sanitation system be put in place to minimise any potential environmental impacts.     

The impact of land use change on water balance in Zhangye city,China

Land use change has a significant effect on water balance, especially in arid region, such as Northwest China. In this paper, we analyze the effect of land use change on water balance in terms of the amount of water supply and demand from economic perspective. It's the first time to extend the basic 48 sectors input-output table to include water and land accounts that involved into multiple production processes for Zhangye city. We then perform the improved ORANI-G model, a single region Computable General Equilibrium (CGE) model, to analyze the effect of land use change on water balance under three scenarios. Subsequently, scenario-based simulation results are interpreted through selected sectors from agricultural, industrial, and service sectors respectively. Finally, the effect of land use change on water balance is analyzed through the difference between business-as-usual and land use unchanged scenarios. The results show that the extent of effect on water balance is different among sectors. Specifically, from the perspective of absolute value, service sectors are the largest, followed by industrial sectors, and the agricultural sectors are the least. Conversely, in terms of percentage change of land use, the largest extent of effect occurs in agricultural sectors. Additionally, with the rapid urbanization and the development of social economy, water balance in industrial sectors and service sectors will be stricken and reconstructed to a new high level. Simulation results also show that agricultural land shrinking will mitigate water scarcity distinctly, which indicates that balance the relationship among different stakeholders is imperative to guarantee water transformation from agricultural sectors to industrial and service sectors.