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1.
北京城乡过渡区土地利用变化驱动力分析   总被引：52，自引：1，他引：52  
在多时相遥感数据和实际调查数据的支持下，采用典型样带和样点相结合的研究方法，对北京西部城乡过渡区的土地利用/覆盖变化驱动力进行了研究。结果表明，研究区的土地利用/覆盖变化受到了不同层次、多种驱动力的综合作用，人类活动从整体上改变着城乡过渡区的景观特征，政策体制转变下的经济高速增长和快速的城市化过程是北京城乡过渡区土地利用/覆盖变化的根本原因。在这个过程中，城市投资和产业的转变与农村农业用地内部的结构调整相互结合，从城市和农村两个方向共同推动着北京城乡过渡区的土地利用/覆盖变化，而地形、交通等因素则从局部尺度上决定着土地利用/覆盖变化的方向。此外，人类个体的行为选择，尤其是就业和消费选择，也在一定程度上对北京城乡过渡区的土地利用/覆盖变化起着调整和修改作用。  相似文献   

2.
徐倩  李阳兵  黄娟 《中国岩溶》2018,37(4):545-554
选取贵州省清镇市近郊村域王家寨地区为研究对象,在GIS支持下,利用该区域1963年、1982年、2005年、2010年和2015年5期土地利用图形数据叠加分析,提取出研究区50余年来的土地利用/覆盖信息,并结合相应的社会经济统计数据,分析了其驱动力因子,其结果表明:(1)1963—2015年间,土地覆盖类型的总体变化为高被草地和平坝旱耕地明显减少,低被草地、农村居民点、工矿用地、公路用地面积大幅增加,其中,平坝旱耕地有向经济效益更高的土地利用方式转变的趋势;（2）景观格局演变的总体趋势是:自1963年起,斑块数量、斑块密度持续增加,到2015年呈下降趋势,而最大斑块指数逐年减小,形状趋于不规则,同时,近50年景观的多样性指数持续增加;（3）区内土地利用/覆盖和景观格局呈阶段性变化,从1963年到2005年,坡地土地利用活动较强,2005年后,平地土地利用强度增加、农业逐渐转型、聚落持续扩展;（4）区内土地利用及景观格局的变化主要受经济、人口和政策因素的影响。   相似文献   

3.
近15a乌鲁木齐市城市用地扩展动态及其空间特征研究   总被引：2，自引：0，他引：2  
黄粤  陈曦  包安明  马勇刚 《冰川冻土》2006,28(3):364-370
以乌鲁木齐市为例,在遥感和GIS技术的支持下,对干旱区城市土地利用结构、空间格局动态变化与城市扩展的空间特征进行定量分析.采用1987年、2002年两期陆地卫星影像为基础数据源,提取了研究时段内乌鲁木齐城市土地利用变化信息;结合景观生态学原理和方法,对研究区城市景观的动态变化进行定量分析.并引入建成区空间密度作为定量指标,分析总结了乌鲁木齐市扩展变化的空间特征.结果表明,1987-2002年间乌鲁木齐城市土地利用状况发生了较大的变化:城市建成区和绿地面积增长,水体面积减少;景观斑块分离度增强,边界构成曲折化,整体格局趋于复杂;在空间上,城市扩展主要沿西、西北及东北3个主要方向进行,并形成了建成区密度由内而外递减的空间分异特征.  相似文献   

4.
The integration of remote sensing, geographic information system, landscape ecology and statistical analysis methods was applied to study the urban thermal environment in Guangzhou. Normalized Difference Vegetation Index (NDVI), Normalized Difference Build-up Index (NDBI), Normalized Difference Barren Index (NDBaI) and Modified Normalized Difference Water Index (MNDWI) were used to analyze the relationships between land surface temperature (LST) and land use/land cover (LULC) qualitatively. The result revealed that, most urban built-up lands were located in the middle part, and high LST areas mostly and were in the middle and southern parts. Therefore, the urbanization and thermal environment in the middle and southern parts need to be determined. Land surface temperature increased with the density of urban built-up and barren land, but decreased with vegetation cover. The relationship between MNDWI and LST was found to be negative, which implied that pure water would decrease the surface temperature and the polluted water would increase the surface temperature. A multiple regression between LST and each indices as well as the elevation was created to elevate the urban thermal environment, which showed that NDVI, NDBI, NDBaI, MNDWI were effective indicators for quantifying LULC impacts on LST.  相似文献   

5.
Rapid land-use change has taken place in many arid and semi-arid regions of China over the last decade as the result of demand for food for its growing population. The Heihe River Basin, a typical inland river basin of temperate arid zone in northwestern China, was investigated to assess land-use change dynamics by the combined use of satellite remote sensing and geographical information systems (GIS), and to explore the interaction between these changes and the environment. Images were classified into six land-use types: cropland, forestland, grassland, water, urban or built-up land, and barren land. The objectives were to assess and analyze landscape change of land use/cover in Heihe River Basin over 15 years from 1987 to 2002. The results show that (1) grassland and barren land increase greatly by 22.3, and 268.2 km2, respectively, but water area decreased rapidly by 247.2 km2 in the upper reaches of Heihe River Basin; (2) cropland and urban or built-up land increased greatly by 174.9, and 64.6 km2, respectively, but grassland decreased rapidly by 210.3 km2 in the middle reaches of Heihe River Basin; and (3) barren land increased largely by 397.4 km2, but grassland degraded seriously and water area decreased obviously by 313.3, and 21.7 km2, respectively in the lower reaches of Heihe River Basin. These results show that significant changes in land-use occur within the whole basin over the study period and cause severe environmental degradation, such as water environmental changes (including surface water runoff change, decline of groundwater table and degeneration of surface water and groundwater quality), land desertification and salinization, and vegetation degeneracy.  相似文献   

6.
Despite continuing efforts to upgrade the urban storm sewer system since the late 1950s, the City of Shanghai is still vulnerable to persistent rainstorm waterlogging due to excess surface runoff and sewer surcharge, which frequently cause significant damage to buildings and disruption to traffic. Rapid urbanization and associated land cover changes are the major factors contributing to waterlogging. However, it is unclear to what extent changes in rainfall variability over the past few decades are also involved. This paper investigates the combined impacts of land use and land cover change, storm sewer development, and long-term variations in precipitation. Evidence of persistent waterlogging is presented first. We then give an account of land surface modifications during the process of urbanization and the development of the city??s urban storm sewer system. Statistical analysis suggests that the increase in runoff coefficient due to conversion of lands from agricultural to industrial, commercial, and residential uses is a major factor driving greater waterlogging risk. In particular, historical analysis of aerial photographs reveals the rate and extent of modification to river networks in the past few decades. The natural drainage network has shrunk by 270?km, significantly reducing the city??s capacity to transport excess surface flow. In line with other studies, we find no significant overall trends in annual rainfall totals (at Baoshan and Xujiahui). However, seasonal and monthly rainfall intensities have increased. At the daily scale, we find that compared to pre-1980s: (i) there has been an increase in the number of wet days with precipitation exceeding 25?mm (Heavy Rainfall) and decrease in those below 25?mm and (ii) the number of consecutive wet days with precipitation maximum and average exceeding the threshold known to cause waterlogging shows an increasing trend. Since rainfall intensity is expected to increase under climate change, this could further compound the impacts of land use changes and place even greater pressure on the existing storm sewer system.  相似文献   

7.
Remote sensing is an effective method to monitor environmental change. To study the influence of mining and mine dump on the environment of mine, remote sensing is used to monitor the change of land use and vegetation in the ore area, and to forecast the ecological environment by considering the mining speed. Remote sensing images at different periods were collected in the study, which include MSS images in 1975, TM images in 1990, 1995, 2000 and 2005, and SPOT-5 images in 2002. At the same time, relief map and geological map of the ore area were also collected as assistant data for remote sensing interpretation. After color synthesis, enhancing treatment and geometrical revision, the interpreted dynamic information on remote sensing images was edited with ARC/INFO software, to build a dynamic monitoring database for land use in the ore area from 1975 to 2005 and a database for land use in 1975, 1990, 1995, 2000, 2002 and 2005. Through interpretation, it is found that, after 30 years of mining activities, the vegetation area in the Panzhihua mining area was reduced from 9352.6 ha in 1975 to 8195.6 ha in 2005, and its grassland area from 1053 ha in 1975 to 795.5 ha in 2002. After that, the grassland area increased to 869.1 ha in 2005 because of re-cultivation of some mine dumps.  相似文献   

8.
C. Y. Jim Dr. 《GeoJournal》1989,18(2):175-188
The urban tree cover of a sample area in Hong Kong, selected for its exceptionally good tree cover that penetrate the built-up matrix, was mapped at 15000 scale using aerial photographs. Distribution and configuration of cover was quantified by systematic line sampling. Sampled segments were assigned to appropriate habitat types, urban zones and land uses. Chi-square analysis was employed to detect associations between some observed pairs. Attributes to characterize tree cover and habitats were proposed. Tree cover was found predominantly on slopes well mixed with the urban matrix. Patches of trees in roadside habitats and offroad open spaces were small and disconnected in rigid geometric patterns. Natural slopes unaffected by urban development supported woodlands at high elevation outside the city boundary. Cover in artificial or natural residual slopes (undeveloped slopes embedded within the urban matrix) showed wide variations. Most of the narrow curvilinear units were oriented along contours and situated between roads and buildings. Cover and segment size increased progressively from coastal reclaimed zones to the upslope lands. Areas of high-density land use had scanty cover; most tree cover was found outside subdivided lots in places of lower density land use. Topographical control of urban morphology, habitat and cover characteristics were evident. The dimension, orientation and connectedness of the largely unplanned residual-slope cover were inadequate as wildlife refuges. The principles and possible applications of island biogeography theory in the urban setting was assessed. The dynamic interaction between urbanization and tree cover was summarized. Potential for neighborhood nature parks should not be wasted. Possibilities to protect and enhance tree cover and mould its configuration in a landscape plan in existing and new urban areas were discussed.  相似文献   

9.
Changes of land cover in the Yarlung Tsangpo River basin from 1985 to 2005   总被引：1，自引：0，他引：1  
Land cover is closely related to environmental changes and socioeconomic development. Land-cover change in the Tibetan Plateau (TP) is different from that in the lowlands; however, a detailed land-cover change in areas such as the Yarlung Tsangpo River (YTR) basin in the TP has not been reported. To fill this gap, the current study explores the land-cover change between 1985 and 2005 in the YTR basin. The results show that only 1 % of the land cover in the YTR basin changed during this time period. The most significant land-cover changes included increases in forest and built-up areas as well as decreases in grassland, water and wetland areas. By percentage, the most rapid land-cover change occurred for built-up areas with an annual variation of 2.07 %. There was an obvious vertical distribution pattern for land-cover types in the YTR basin; from low to high, the average altitudes were forest, farmland, built-up, grassland, water and wetland, and bare land. The average altitude and slope for most land-cover types did not vary over the past 20 years. However, the average altitude and slope of built-up significantly decreased, especially in the zone between 3,500 and 4,000 m. The water and wetland area in altitudes above 4,500 m increased; however, they decreased in the zone between 3,500 and 4,000 m. Natural factors cause most land-cover changes, whereas the increasing intensity of human activities cause some changes to built-up and farmland. Additional attention should be paid to the study of the mechanism of land-cover change in the TP.  相似文献   

10.
This paper investigates the urban heat island (UHI) characteristics of Shanghai, China, during 1981–2010 using Landsat thematic mapper/multispectral scanner and moderate-resolution imaging spectroradiometer satellite data from the perspectives of time and space, with further analysis of the landscape pattern, the urban heat island effect ratio, and formative factors. The results show the following: (1) From the interannual variation, the secondary-medium temperature area and the medium temperature area are the main bodies of Shanghai UHI, accounting for 67.16–83.69 % of the total area, and have a rising trend over time. (2) From the landscape pattern, the secondary-medium temperature area and the medium temperature area have a dominant position over the whole UHI landscape pattern of Shanghai; the relatively high-temperature area gradually decreases, and its dominance over the whole UHI landscape pattern declines. (3) From the spatial distribution, the pattern in which the urban area initially had complete domination has gradually transformed to become primarily urban area centered and other construction land supplemented with rapid urbanization. Rapid increase of the green land in the urban area has to some extent reduced the UHI characteristics of the Shanghai area in recent years.  相似文献   

11.
钱大文  颜长珍  修丽娜 《冰川冻土》2020,42(4):1334-1343
矿区开发会导致周边土地覆被及景观格局发生剧烈变化， 但目前对青藏高原典型矿区及其周边土地覆被长时间序列变化缺乏动态监测， 尤其缺乏对景观格局脆弱性响应特征的深入认识， 因此无法针对矿区合理开发和生态修复等提出有效的科学指导。通过遥感技术和土地变化科学研究手段， 以及景观格局脆弱性概念， 对青藏高原北部木里矿区及周边1975 - 2016年土地覆被时空变化和景观格局脆弱性进行分析和评估。结果表明： 木里矿区在2000年后剧烈扩张， 导致周边土地覆被面积缩减， 其中高寒草甸湿地面积损失最大， 其次为其他和高寒草甸。矿区开发对周边生态系统的间接影响效应在逐渐增大， 表现为水域面积减少， 高寒草甸湿地出现退化以及矿区发生少量逆转。受矿区扩张影响， 区域景观格局脆弱性不断增强， 可能对周边生态系统服务功能产生负面影响。因此， 未来矿区的生态修复和规划过程中， 应当优化景观格局， 降低景观格局脆弱性。研究成果可为青藏高原及其他生态脆弱地区的矿区合理开发规划及生态修复等工程提供一定参考。  相似文献   

12.
彭建  蔡运龙  王秀春 《中国岩溶》2007,26(2):137-143
通过运用遥感、地理信息系统以及全球卫星定位系统等技术手段,借助于景观生态学中的景观格局指数以及构建生态价值指数,对位于贵州中部典型喀斯特地区的猫跳河流域1973年以来的土地利用/覆被变化及其对整个区域生态环境状况的影响以及近30年来土地利用的合理性进行了评价。研究表明,在过去的30年间,研究区的土地覆被发生了显著的变化,并对区域的生态环境造成了深刻的影响。1973- 1990年,猫跳河流域的景观趋于破碎化,斑块总数从3 438个增加到3 619个,生态服务价值指数从3 626. 58降低到3 343. 47,土地利用具有明显的不可持续性; 1990- 2002年,猫跳河流域的景观破碎度降低,斑块数量从1990年的3 619个减少到3 312个,整个流域的生态服务指数从3 343. 47上升到3 738. 4,生态环境质量开始向好的方向发展。   相似文献   

13.
Rapid urbanization has profoundly transformed the spatial pattern of urban land use, and the urban hills are facing changes in Jinan City. Urbanization has had and continues to have a negative impact on urban mountain area within city. With the rapid development of Jinan’s urbanization and civilization, urban mountainous environment issues, such as destruction of mountain body, soil and water loss, soil erosion, and degeneration of vegetation, are becoming more serious. These have resulted in the serious natural hazards in the karst mountainous region of Jinan City, i.e. mining landslide, debris flow, and mountain collapse.  相似文献   

14.
This paper examines the coastal regional trends in urbanization processes using remotely sensed images around the Kucukcekmece Lagoon as a case study, located in the western part of Istanbul, Turkey. Throughout the examination process, the coastline changes are determined for a long-term period. To achieve this goal, post-classification comparison method is applied to the CORONA and LANDSAT TM satellite images of 1963, 1987 and 2005. In order to identify the land use changes, common landscape structures in the region were distinguished as water, green and open land, urban and industrial areas. Due to the mix up of land-cover types between urban and industrial areas, the classified images are integrated with geographic information system data obtained from visual interpretation of the enhanced images and auxiliary data sets. The results of the change analyses in coastal region showed that important alterations are taking place in the area due to the unplanned urban and industrial expansions that has irreversibly changed the physical features of the Kucukcekmece Lagoon. According to image classification results, the urban land use area increased from 2 % oftotal area in 1963 to 38 % in 1987 and 46 % in 2005, most of which converted from agricultural and greenlands. At the same time, the ecological impact of the loss of specific land covers is highlighted based on the results of the land use changes and the previous scientific applications. Furthermore, some recommendations are given to planners, decision makers and politicians to maintain the sustainable coastal ecosystem management.  相似文献   

15.
Land use and land cover changes are local and place specific, occurring incrementally in ways that often escape our attention. This study sought to detect changes in land cover in the Tema Metropolis of Ghana from 1990 to 2010. Multispectral Landsat Thematic Mapper data sets of 1990, 2000 and 2007 were acquired, pre-processed and enhanced. Unsupervised classification of the images was performed and six land cover classes (water, wetlands, closed vegetation, open vegetation, cropped lands, and built-up) were derived. The post-classification change detection technique was performed to derive the changes in land cover and their corresponding change matrices. Between 1990 and 2010, built-up areas expanded steadily to become the most prevalent land cover type in the metropolis, reducing vegetation cover dramatically. High population growth with its attendant rise in the demand for housing, and increasing commercial activities, were found to have influenced land cover changes over the period.  相似文献   

16.

It is axiomatically true that urbanization in India's metropolises and large cities has been exacerbated since the beginning of the millennium, consuming the natural and semi-natural ecosystem on the outskirts of the city, resulting in a zone with a distinct climate known as urban climate. Such a climate—the result of a built-up environment is distinctly different from the natural climate as the paved surface and concrete skyscrapers not only destroy the natural ecosystem, it peculiarly induce a different kind of insolation, cooling and air drainage were lacking in green space, water bodies and open space cannot accommodate with environmental rhythm properly, resulting into the accumulation of heat, ecological derangement of subsurface soil which can easily be predicted by GIS analysis. This paper is an attempt to measure urban growth and its impact on the environment in the metropolitan city Kolkata. The use of satellite data and GIS techniques to detect urban expansion is a highly scientific strategy. Using geospatial techniques, the current study attempts to examine major urban changes in Kolkata and its surroundings from 1988 to 2021. Landsat 5 TM and Landsat 8 OLI temporal data are used to identify land-use change through unsupervised classification; Spectral Radiance Model and Split Window Algorithm method are used for identifying land surface temperature change. SRTM DEM (30 m) has been used to identify flood risk zones and several spectral indices like Normalized Difference Vegetation Index and Modified Normalized Difference Water Index are a further extension for environmental assessment. By all such suitable methods, a clearer change in an urban environment is detected within the period of 33 years (1988–2021). The result shows that the population changes, vegetation cover and built-up area, and accessibility are at a rapid rate. These changes are causing major environmental degradation in the city. The classification result indicates that appropriate land use planning and environmental monitoring are required for the long-term exploitation of these resources.

  相似文献   

17.
National nature reserves in China protect ecosystem and well-being in its region while benefiting humans by providing ecosystem services. Land-use/cover changes result in changes in the landscape pattern and affect the provision of ecosystem service value (ESV). The monetary evaluation of spatial–temporal changes in landscape patterns and ecosystem services in the arid region of China has been inadequately studied. Therefore, the Ebinur Lake Wetland National Nature Reserve (ELWNNR) in the arid region of China was chosen as a study object to evaluate the spatial–temporal variation in ecosystem service values (ESVs) under changes in land use/cover. The research analysed land-use/cover change in ELWNNR using a Sankey diagram, the spatial–temporal variation in ELWNNR ESVs using ArcGIS. Meanwhile, it also analysed the landscape patterns and total ESVs of the core area, buffer area and experimental area of ELWNNR at a regional scale. Four Landsat data sets from 1972, 1998, 2007 and 2016 were chosen to estimate the changes in land-use/cover types and ESV in ELWNNR. Meanwhile, the sensitivity of ESV was also analysed to validate the estimation of ESV in ELWNNR. The results showed that the total ESV of ELWNNR was 3.12?×?109 CNY (USD$ 4.88?×?108) in 1972 and dropped to 2.71?×?109 CNY (USD$ 4.24?×?108) in 2016. The provision of total ESV in ELWNNR decreased by approximately 0.41?×?109 CNY (USD$ 6.42?×?107) from 1972 to 2016, although there were fluctuations in 1998 and 2007. The core area possessed the highest ESV among all the areas, showing an increase in the provision of ESV in ELWNNR. All the areas of ELWNNR became highly fragmented, and the landscape patterns became more complex during this time period. The results of the study provide sufficient information about the ecosystem services in the region in the absence of complete data sets and contribute to conservation planning of national nature reserves.  相似文献   

18.
利用社会经济统计数据和水文气象资料,探讨城市化背景下北京城市洪涝特征、形成机制及影响因素。近50年来城市内涝逐渐成为北京洪涝灾害的主要类型,随着城市化迅猛发展,城市内涝积水点数量在时间上表现为显著增加趋势,在空间上呈现出由内环逐步向外环扩张趋势,与城市化发展空间格局关系密切。从水循环的角度分析城市洪涝形成机制,指出区域气候变化和城市化发展改变了城市降水格局,汛期降水量和极端降水事件呈现下降趋势,但城区短历时强降水事件呈现增加态势;城市化发展改变了区域下垫面条件、城市流域产汇流特性和城市排水格局,进而影响了区域水循环过程和水量分配,在一定程度上增加了城市洪涝灾害风险;同时城市基础设施建设水平不足、排水排涝标准偏低、应急管理能力不足等因素,导致城市洪涝发生风险增加,降低了城市洪涝综合应对能力。  相似文献   

19.
This paper describes the spatiotemporal changes pertaining to land use land cover (LULC) and the driving forces behind these changes in Doodhganga watershed of Jhelum Basin. An integrated approach utilizing remote sensing and geographic information system (GIS) was used to extract information pertaining to LULC change. Multi-date LULC maps were generated by analyzing remotely sensed images of three dates which include LandSat TM 1992, LandSat ETM+ 2001 and IRS LISS-III 2005. The LULC information was extracted by adopting on-screen image interpretation technique in a GIS environment at 1:25,000 scale. Based on the analysis, changes were observed in the spatial extent of different LULC types over a period of 13 years. Significant changes were observed in the spatial extent of forest, horticulture, built-up and agriculture. Forest cover in the watershed has decreased by 1.47 %, Agricultural by 0.93 % while as built-up area has increased by 0.92 %. The net decrease in forest cover and agriculture land indicate the anthropogenic interference into surrounding natural ecosystems. From the study it was found that the major driving forces for these changes were population growth and changes in the stream discharge. The changes in the stream discharge were found responsible for the conversion of agricultural land into horticulture, as horticulture has increased by 1.14 % in spatial extent. It has been found that increasing human population together with decreasing stream discharge account for LULC changes in the watershed. Therefore, the existing policy framework needs to focus upon mitigating the impacts of forces responsible for LULC change so as to ensure sustainable development of land resources.  相似文献   

20.
应用集成的遥感识别技术进行土地利用变化分析   总被引：6，自引：0，他引：6  
以厦门市为研究区域,以1988-1998年为时间跨度,利用Landsat5TM遥感数据开展土地覆盖变化识别中多种遥感数据处理方法的集成应用研究。以后分类比较法的结果为基础,运用改进的差值法定义的"变化"目标进行修正,将两种方法有机集成综合地确定土地覆盖变化。根据变化前与变化后覆盖不同但土地利用方式相同或类似的原则进行合并处理,最后得到厦门市10年间土地利用结构变化各种成因类型及其数量。结果表明,10年间厦门市因城市化引起的土地覆盖变化为590．83km2,变化强度为31.14％,引起厦门市土地利用结构发生变化主要有 8种成因机制类型,面积达351.99km2,变化强度为18.55％。  相似文献   

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