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基于遥感数据的全球及区域土地覆盖制图--现状、战略和趋势 总被引：21，自引：4，他引：17
土地利用／土地覆盖变化研究是近年来全球变化研究的焦点之一。全球和区域尺度的土地覆盖特征对全球环境状况的评估、模拟未来全球环境的情景有重要的作用。2000年在Internat ionalJournalofRemoteSensing杂志上出版了题为"GlobalandRegionalLandCoverCharacterizat ion from Remotely Sensed Data"的专辑。在此基础上,介绍、总结了国际上利用遥感影像进行全球和区域等大尺度土地覆盖研究的新进展。分别从数据源与制图的时空尺度、制图方法（数据预处理、分类、精度评估）等方面进行了介绍,并对现今的两个全球土地覆盖数据库进行了比较分析。 相似文献
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利用GRACE重力卫星数据反演黑河流域地下水变化 总被引：9，自引：0，他引：9
干旱区地表水资源有限, 地下水资源被超采利用, 黑河流域是西北干旱区典型内陆河流域, 有同样的地下水资源利用问题. 然而由于监测地下水变化的测井数目有限且分布不均, 难以从流域尺度上把握地下水资源的时空变化. 利用GRACE重力测量卫星数据反演黑河流域2003-2008年间的地下水时空变化, 为合理分配利用水资源提供科学依据, 为掌握无资料区域地下水水资源及其变化趋势提供了计算方法. 为验证GRACE反演结果的可靠性, 首先将计算出的黑河中上游地下水的变化, 与该区域实测地下水变化数据进行对比分析, 结果显示二者之间相关性较好, 在一定程度上表明GRACE数据具备反演整个黑河流域水储量变化及其各个组分的能力. 此后, 利用GRACE数据反演了全黑河流域的地下水变化, 对其时空变化进行了分析和讨论. 结果表明: 黑河流域2003-2004年间地下水减少的幅度越来越少, 2005年夏季期间地下水资源量增加量最多, 自此地下水增加幅度逐渐减少, 至2008年趋于平衡. 空间上流域局部变化波动较大, 2003-2004年间黑河上游地下水资源量处于减少状态, 2005年相对于6 a地下水平均含量有轻微增加趋势, 2006年处于6 a平均值状态, 2007-2008年有稍微上升趋势; 中游在2005年有略微的上升, 之后3 a下降; 下游地下水含量在6 a中整体呈上升趋势. 相似文献
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新疆提孜那甫河流域山区冰草生态交错带的空间格局及其动态变化研究 总被引：1，自引：1，他引：0
冰-草生态交错带是陆地生态交错带的重要类型之一, 对其进行有效监测和研究对于生物多样性的保护具有重要意义. 利用2004-2013年近10 a的MODIS10A1数据提取积雪日数, 结合DEM和Landsat影像研究提孜那甫河流域山区的冰-草生态交错带的时空格局及其动态变化. 结果表明: ①近10 a 来交错带的平均面积为5 749 km2, 占研究区总面积的37.83%. ②交错带分布由西南向东北偏移, 在东北坡、东坡分布较西坡和北坡多, 主要分布在海拔4 600~4 900 m的区域; 在坡度大于25°陡坡以上的区域分布较多. ③近10 a间冰-草生态交错带面积总体呈波动上升趋势, 总增长率为10.68%, 年均增长约66.78 km2; 其中2005年和2009年交错带面积较前一年有所明显下降, 而2007年交错带面积上升较为明显; 交错带面积与气温呈强正相关, 与降水呈弱负相关. ④近10 a交错带的平均海拔呈缓慢上升趋势, 2013年的交错带分布的平均海拔较2004年上升了45 m; 而近50 a来研究区高寒草甸带向上爬高了约100 m左右. 相似文献
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库尔勒市城市空间扩展特征及其驱动因素研究 总被引：3，自引：2，他引：1
以库尔勒市1990年、1995年、2000年、2005年、2010年以及2015年6个时期的Landsat TM/ETM+影像作为基础数据,借助ENVI 4.5、Arc GIS 10.1等专业软件对影像进行监督分类和空间分析。在此基础上,分析库尔勒市近25 a来土地利用时空变化规律、城市空间扩展趋势及演变过程、城市重心转移方向及距离和城市空间扩展形态变化特征等。研究表明:近25 a间库尔勒市建设用地面积大幅度增加,所占比例不断上升,年均增加速率为15.18%。耕地和未利用地对城市建设用地扩展贡献较大。城市向东南方向扩展,城市重心向东南方向转移了总共2 118.46 m。城市空间扩展紧凑度呈下降趋势,分形维数呈上升趋势,表明城市空间扩展趋于结构疏散化、形状复杂化。针对于以上特征及扩展趋势,分析了库尔勒市城市空间扩展的驱动因素并提出一些对策建议,为城市可持续发展提供科学依据。 相似文献
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塔里木河北源及干流区域降水变化趋势与多尺度特征对比: 总被引：3，自引：0，他引：3
选择塔里木河北源及干流区12个代表气象站1959-2004年的年降水系列资料,采用线性回归、平滑方法和Morlet小波功率谱等分析方法,对比分析了塔里木河北源与其干流两个不同区域降水变化趋势与多尺度特征.趋势分析表明:近46a来,两区域年降水都存在增加的趋势,但北源区增加的幅度要明显大于干流区;两个区域在1986年前后,降水增加更趋明显.多尺度分析显示,两区域年降水存在集中于2～8a尺度带上的显著周期.其中,北源区域年降水尺度较为分散,大部分站点年降水集中在2～4a尺度带上,准5a～准8a尺度上也有少量分布;干流区域则主要集中于准3a尺度上.另外,由于时间序列长度的限制和其它不确定因素的影响,两区域部分站点检测出的16a以上的年代际尺度不显著. 相似文献
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研究格陵兰冰盖（GrIS）质量变化异常速率可以帮助了解异常气候事件驱动海平面变化的机制.聚焦于2010~2012年GrIS质量变化的异常速率,及其对海平面指纹（SLF）和相对海平面（RSL）变化的贡献.通过联合2003~2015年GRACE月重力场数据和表面质量平衡（SMB）数据,采用mascon拟合法及网格尺度因子恢复泄漏,获得了6个流域的质量变化时空分布.基于海平面变化方程（SLE）并考虑负荷自吸引效应估算了SLF的空间分布.结果表明,2003~2015年间GrIS总质量变化速率分别为-288±7 Gt/a及-275±1 Gt/a;而在2010~2012年间速率相应地增加至-456±30 Gt/a及-464±38 Gt/a,该时期格陵兰西北海岸及东南沿海地区呈现出大量冰盖融化,其对海平面的贡献变化呈现倒“V”型（即先升后降）,而全球平均海平面变化呈现出明显的正“V”型（即先降后升）.另外,GrIS融化对海平面的贡献约为31%,造成全球平均RSL增加了0.07 cm/a,而对斯堪的纳维亚及北欧地区的RSL贡献为-0.6 cm/a,GrIS融化造成的远海地区RSL上升速率比全球平均RSL速率高近30%. 相似文献
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基于Google Earth Engine云平台的植被覆盖度变化长时间序列遥感监测 总被引：3，自引：1，他引：2
基于Google Earth Engine遥感大数据云计算平台,以云南省南洞地下河流域为例,利用近2 000景30 m分辨率Landsat-NDVI长时间序列数据,采用像元二分模型对研究区1988-2016年的年最大植被覆盖度进行定量估算,并分别从流域整体和像元尺度分析近29 a间植被覆盖度的时空变化特征。研究结果表明:（1）南洞地下河流域大部分区域处于中等覆盖度和中高覆盖度,覆盖度随高程和坡度的增加而增大,其中年最大植被覆盖度 > 60%的区域占流域总面积的45.75%;（2）近29 a来,流域年最大植被覆盖度整体呈现不断增加的趋势,年均增长速率为0.56%,其中植被覆盖度轻微改善或是明显改善的面积占38.84%;（3）相比1988年,2016年高植被覆盖区和中高植被覆盖区面积分别增长50.51%、18.40%;而中等植被覆盖区、中低植被覆盖区和低植被覆盖区面积分别减少24.05%、47.95%和37.72%。封山育林等石漠化治理工程以及气候变化对于流域植被恢复和生态环境重建具有重要影响,其研究成果可为后续石漠化监测提供重要的基础研究数据。 相似文献
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开展荒漠化时空动态监测是荒漠化防治的一项重要基础工作。以地处青藏高原东北缘的甘肃省玛曲县为例,以该县2001年、2005年、2010年的TM影像和2015年的HJ-1影像为数据来源,利用Albedo-NDVI特征空间法,从整体到局部,分别对该县全区域及其黄河沿岸地区不同尺度区域近15年的土地荒漠化进行了监测和时空动态分析。研究结果表明：Albedo-NDVI特征空间法能便捷、有效、精确地对荒漠化信息进行提取和分级,有利于荒漠化的定量分析与监测;玛曲县近15年来实施的生态恢复工程效果显著,该县荒漠化状况有所改善,荒漠化土地的面积持续减小,程度不断降低,主要发生“轻度荒漠化土地向非荒漠化土地”的转移;但是由于沙源丰富、人口密集以及过度放牧等原因,玛曲县黄河沿岸5 km带状区域荒漠化以“非荒漠化土地向轻度荒漠化土地”转移为主,荒漠化状况较全县整体水平严重,并且仍有不断恶化的趋势。 相似文献
10.
1970-2009年纳木错湖泊面积扩张的遥感卫星观测证据及原因之商榷 总被引：5，自引：2，他引：3
基于不同时期的遥感影像、航测地形图和DEM, 运用GIS和RS技术对纳木错1970-2009年间湖泊面积变化进行了分析, 利用周边气象台站资料, 通过对纳木错湖面蒸发及降水、冰川融水、非冰川区径流补给的趋势性分析, 从流域水量平衡角度商榷了纳木错湖面扩张的原因. 结果表明: 近40 a来纳木错湖泊面积不断扩张, 尤其是近10 a来最为剧烈, 2001-2009年间湖面扩张超过50 km2. 流域降水变化是纳木错湖泊面积扩张的直接原因, 另外伴随蒸发力下降, 湖面蒸发减少也是湖泊面积扩张的原因之一. 相似文献
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Mohamed Al-shalabi Lawal Billa Biswajeet Pradhan Shattri Mansor Abubakr A. A. Al-Sharif 《Environmental Earth Sciences》2013,70(1):425-437
An effective and efficient planning of an urban growth and land use changes and its impact on the environment requires information about growth trends and patterns amongst other important information. Over the years, many urban growth models have been developed and used in the developed countries for forecasting growth patterns. In the developing countries however, there exist a very few studies showing the application of these models and their performances. In this study two models such as cellular automata (CA) and the SLEUTH models are applied in a geographical information system (GIS) to simulate and predict the urban growth and land use change for the City of Sana’a (Yemen) for the period 2004–2020. GIS based maps were generated for the urban growth pattern of the city which was further analyzed using geo-statistical techniques. During the models calibration process, a total of 35 years of time series dataset such as historical topographical maps, aerial photographs and satellite imageries was used to identify the parameters that influenced the urban growth. The validation result showed an overall accuracy of 99.6 %; with the producer’s accuracy of 83.3 % and the user’s accuracy 83.6 %. The SLEUTH model used the best fit growth rule parameters during the calibration to forecasting future urban growth pattern and generated various probability maps in which the individual grid cells are urbanized assuming unique “urban growth signatures”. The models generated future urban growth pattern and land use changes from the period 2004–2020. Both models proved effective in forecasting growth pattern that will be useful in planning and decision making. In comparison, the CA model growth pattern showed high density development, in which growth edges were filled and clusters were merged together to form a compact built-up area wherein less agricultural lands were included. On the contrary, the SLEUTH model growth pattern showed more urban sprawl and low-density development that included substantial areas of agricultural lands. 相似文献
12.
In recent decades, attaining urban sustainability is the primary goal for urban planners and decision makers. Among various aspects of urban sustainability, environmental protection such as agricultural and forest conservations is very important in tropical countries like Malaysia. In this regard, compact urban development due to high density, rural development containment is known as the most sustainable urban forms. This paper attempts to propose an integrated modeling approach to predict the future land use changes by considering city compactness paradigms. First, the cellular automata (CA) were applied for calculating land use conversion. Next, weights-of-evidence (WoE) which is based on Bayes theory was utilized to calibrate CA model and to support the transitional rule assessment. Several urban-related parameters as well as compact city indicators were utilized to estimate the future land use maps. The results showed how compact development parameters and site characteristics can be combined using the WoE model to predict the probability of land use changes. The modeling approach supports the essential logic of probabilistic methods and indicates that spatial autocorrelation of various land use types and accessibility is the main drivers of urban land use changes. 相似文献
13.
Dynamics of land use/cover changes and the analysis of landscape fragmentation in Dhaka Metropolitan, Bangladesh 总被引：3，自引：0，他引：3
Rapid urban expansion due to large scale land use/cover change, particularly in developing countries becomes a matter of concern since urbanization drives environmental change at multiple scales. Dhaka, the capital of Bangladesh, has been experienced break-neck urban growth in the last few decades that resulted many adverse impacts on the environment. This paper was an attempt to document spatio-temporal pattern of land use/cover changes, and to quantify the landscape structures in Dhaka Metropolitan of Bangladesh. Using multi-temporal remotely sensed data with GIS, dynamics of land use/cover changes was evaluated and a transition matrix was computed to understand the rate and pattern of land use/cover change. Derived land use statistics subsequently integrated with landscape metrics to determine the impact of land use change on landscape fragmentation. Significant changes in land use/cover were noticed in Dhaka over the study period, 1975–2005. Rapid urbanization was manifested by a large reduction of agricultural land since urban built-up area increased from 5,500?ha in 1975 to 20,549?ha in 2005. At the same time, cultivated land decreased from 12,040 to 6,236?ha in the same period. Likewise, wetland and vegetation cover reduced to about 6,027 and 2,812?ha, respectively. Consequently, sharp changes in landscape pattern and composition were observed. The landscape became highly fragmented as a result of rapid increase in the built-up areas. The analysis revealed that mean patch size decreased while the number of patches increased. Landscape diversity declined, urban dominance amplified, and the overall landscape mosaics became more continuous, homogenous and clumped. In order to devise sustainable land use planning and to determine future landscape changes for sound resource management strategies, the present study is expected to have significant implications in rapidly urbanizing cities of the world in delivering baseline information about long term land use change and its impact on landscape structure. 相似文献
14.
城镇用地动态扩展及驱动力分析——以天津市为例 总被引：3，自引：1，他引：2
使用1980年代中后期、90年代中期和2000年土地利用数据以及2007年覆盖天津市的中巴资源02星影像,采用人机交互式解译2007年影像得到整个研究期的城镇动态扩展变化信息,分析了天津小同时期城镇扩展的过程、特征、速度和强度.通过计算天津各个区县的城市扩展强度指数(UII)并采用自然断裂点分类来分析城镇扩展的空间分异,采用分维数分析了城镇扩展的形状特征演变,围绕新城和主要交通线建立缓冲区总结出一些城镇扩展的结论和建议.最后,分析了天津近20多年来城镇扩展占用周边土地的情况,并粗略探讨了影响天津城市扩展的自然与社会经济因素. 相似文献
15.
Peter M. Townroe 《Geoforum》1984,15(3):335-347
The prospects for economic growth among the developing countries of the world over the next two decades are not as promising as the experience of the last two decades. Aspects of the current world economic environment have implications for the pattern of urban growth in developing nations, and hence for the role of spatial policies. This paper outlines the U.N. projections for the growth of urban populations in the world. It then reviews the current external economic situation of the developing countries, faced by world economic recession and high levels of international indebtedness, before considering some of the implications of this situation for urban growth. 相似文献
16.
This paper employs GIS (geographic information systems) technology to visually display the locations of massacres associated with Guatemala’s civil war. While there have been other, more general maps published depicting the spatial dimensions of violence in Guatemala, few other maps depict this information at the department level, nor have they included information on indigenous populations and physical geography.These maps are part of the emerging field of human rights GIS. For example, over the past two decades, maps have become tools of empowerment in Central America and elsewhere, maps usually made with GIS technology. Indigenous groups in many countries in particular have embraced GIS technology and have begun to use maps as tools in their fight for land and marine resources, as well as greater political autonomy. In the case of massacres in Guatemala, displaying exactly where violent acts took place is one way to educate the Guatemalan public regarding the terrible violence of the recent past. Knowing the name of a specific town where a massacre took place is more concrete, potentially leading to perception of place and people, rather than simply being aware of violence in the countryside. 相似文献
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基于遥感与GIS的中国城镇用地扩展特征 总被引：9，自引：0，他引：9
利用中国1990—2000年土地利用矢量数据和自然区划图,将中国分为6级城镇用地区。第一级城镇用地分类包括辽东胶东山地丘陵、华北平原、鲁中山地丘陵、淮河及长江中下游平原、粤桂闽丘陵平原、华北山地丘陵。这些地区城镇用地比重高,城镇扩展速度快,城镇扩展面积占全国城镇扩展面积的71．47％,城镇扩展造成耕地面积减少占全国的69．88％;其中华北平原占全国的24．54％,淮河及长江中下游占20．15％。城镇扩展占用的主要是耕地资源,占其扩展面积的78．96％;其次农村居民点用地占10．2％,林地占4．48％,草地占2．6％,水体占1．56％,独立工矿用地占1．43％,未利用地占0．77％。城镇居民点用地扩展占用大量的耕地资源,从而造成耕地资源的大量减少,威胁中国的粮食安全。 相似文献
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Basic to the study of urban growth is information on population and land use changes. These basic data are generally lacking in Nigeria. This paper examines and assesses the growth of urban land use of Lagos (the Federal Capital of Nigeria) through a systematic utilization of sequential serial photographs (taken in 1962 at a scale of 1:40,000, and in 1974, at a scale of 1:20,000) and computer techniques. The land use data resulting are then used in evaluating the population growth of Lagos. The resulting population estimate is then compared with the available population data. The study concludes by recommending the use of remote sensing, especially aerial photography for the acquisition of basic urban data not only in Nigeria but also in other developing countries lacking in such data. 相似文献
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Application of Remote Sensing in Flood Management with Special Reference to Monsoon Asia: A Review 总被引：4，自引：1，他引：4
The conventional means to record hydrological parameters of aflood often fail to record an extreme event. Remote sensingtechnology along with geographic information system (GIS)has become the key tool for flood monitoring in recent years.Development in this field has evolved from optical to radarremote sensing, which has provided all weather capabilitycompared to the optical sensors for the purpose of flood mapping.The central focus in this field revolves around delineation of floodzones and preparation of flood hazard maps for the vulnerable areas.In this exercise flood depth is considered crucial for flood hazardmapping and a digital elevation model (DEM) is considered to bethe most effective means to estimate flood depth from remotelysensed or hydrological data. In a flat terrain accuracy of floodestimation depends primarily on the resolution of the DEM. Riverflooding in the developing countries of monsoon Asia is very acutebecause of their heavy dependence on agriculture but any floodestimation or hazard mapping attempt in this region is handicappedby poor availability of high resolution DEMs. This paper presents areview of application of remote sensing and GIS in flood managementwith particular focus on the developing countries of Asia. 相似文献