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基于遥感数据的流域土壤侵蚀强度快速估测方法 总被引:20,自引:0,他引:20
以北京延庆县境内的妫水河流域为例, 提出了一种基于遥感数据的土壤侵蚀强度快速估测方法。首先, 利用遥感数据和植被指数模型提取流域内土地利用类型信息和植被覆盖度信息; 其次, 利用数字高程模型数据生成坡度图; 然后, 结合土壤侵蚀强度分级指标, 将坡度图与土地类型图、植被覆盖度图空间叠加, 判断和计算侵蚀强度等级, 结果获得了流域土壤侵蚀强度等级图; 最后, 计算了流域的年平均侵蚀模数。结果表明, 妫水河流域的土壤侵蚀以微度和轻度为主, 所占面积比例为74.88% , 极度和剧烈侵蚀很少, 不到总面积的2%。整个流域的年侵蚀模数估计为1 74611/ km 2·a。 相似文献
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以遥感数据和观测数据为数据源,基于改进的SEMMED土壤侵蚀模型,对祖厉河流域1999年和2001年土壤侵蚀的空间变换进行了模拟和对比。结果表明,流域土壤侵蚀最严重的区域主要集中在葛家岔站点附近、草滩站附近和北部葛家寨和靖远一带,流域中南部的土壤侵蚀通常小于北部。在北部的屈吴山,以及与宁夏交界的月亮山还有华家岭由于植被覆盖度较高,很好的起到了减少径流,抑制土壤侵蚀的作用。降水的年际差异导致本区的土壤侵蚀年际差异较大。 相似文献
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土壤侵蚀调查中的遥感应用综述 总被引:7,自引:0,他引:7
土壤侵蚀引起土壤肥力下降、土地退化及荒漠化和生态环境恶化等一系列区域性和世界性的重大环境问题。中国是土壤侵蚀最严重的国家之一。遥感是进行环境和灾害动态监测的有效技术手段。自从20世纪70年代以来.人们就开始应用遥感技术进行土壤侵蚀的调查。对遥感技术在土壤侵蚀调查中的应用方法进行概括和汇总,分别是影像判读法、指数提取法、图像分类法、光谱分解和正射影像DEM提法等方法,分析不同方法之间的优缺点以及它们各自的适用范围,并结合当前研究的热点问题,指出未来研究的重点及趋势。 相似文献
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The primary objective of this paper is to identify soil erosion zones and to suggest appropriate measures for control of soil erosion using remote sensing, GIS and conventional technique in the Phulang Vagu watershed in the Sriramsagar catchment area of Andhra Pradesh. The digital imagery data of the study area is obtained from the IRS-IC (LISS-III) satellite whereas the toposheets and rainfall data of the study area were obtained from the Survey of India. Satellite images were interpreted to prepare land use/land cover maps by using ERDAS image processing system. Out of 725.983 km 2 of the study area, about 301.435 km 2 is wasteland which is identified as susceptible for soil erosion. Toposheets of the study area were used to prepare drainage and slope maps. Drainage pattern is mainly dendritic with a density of 1.26 km -1 and the stream slope is 0.00614. The arithmetric average method is used to find average annual rainfall. The above parameters were used to calculate the amount of soil erosion from the catchment area. It was found that 882.389 m 3 km -2 year -1 of soil is being eroded from the catchment area which is more than the value adopted in the design of Sriramsagar reservoir. Therefore soil conservation measures such as vegetative cover in the waste land are needed and 12 check dam sites have been proposed by superimposing drainage map and slope map in conjunction with land use/land cover map. With these soil conservation measures, the soil erosion could be kept within the design value of Sriramsagar reservoir. 相似文献
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应用卫星遥感技术监测生态建设工程 总被引:5,自引:1,他引:5
生态建设工程监测的主要目的是了解工程的治理面积和工程质量。对下垫面的动态监测,也就是对实施生态建设工程引起的植被、土壤等改变量的监测,是实现该目的的有效途径。基于3S技术的有机结合和常规手段的辅助,通过一系列遥感数据和实测数据的处理分析,建立了解译标志,完成了对生态建设工程实施前后两年遥感图像的解译,利用地理信息系统矢量化解译的图斑,经统计分析,得到了生态建设工程的治理区域和工程质量数据,为有关生态建设的决策提供了科学依据。另外,还分析了气候条件与生态工程树草成活率的关系。 相似文献
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The quantitative estimation of fractional cover of photosynthetic vegetation(f PV),non-photosynthetic vegetation(f NPV),and bare soil(f BS) is critical for grassland ecosystem carbon storage,vegetation productivity,soil erosion and wildfire monitoring.The ecological importance of NPV has driven considerable research on quantitatively estimating NPV in diverse ecosystems including croplands,forests,grasslands savannah,and shrublands using remote sensing.This paper reviews the research progress in estimating f NPV using hyperspectral and multisspcetral remote sensing data,and hightlights discusses the theoretical bases of PV,NPV and BS spectral characteristics.based on the existing methods for estimating f NPV,this article groupd into two categories:empirical relationship between spectral index and NPV cover,and Spectral mixture analysis.Meanwhile,also discuss applications.of hyperspectral and multisspcetral remote sensing data.Finally,the existential problems and research trends for NPV estimation are analyzed. 相似文献
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Appropriate up-scaling methods to infer spatial information from a finer to a coarser spatial resolution are required when remote sensing and geographical information systems (GIS) are used to generate multi-scale maps that are needed for agriculture, forestry, natural resources, environmental systems, and landscape ecology. The existing methods used in commercial GIS and image analysis packages such as Window Averaging (WA) often do not work well because of different limitations. In this study we developed and compared five widely used WA methods including three spatial variability-weighted methods and two simulation methods. These methods were assessed in a case study for aggregating and using Landsat Thematic Mapper (TM) images for mapping vegetation covers and for inferring a topographical factor related to soil erosion from finer to coarser resolutions. The results showed that the Beta Distribution Simulation (BDS) method was better than WA regardless of the distributions of the spatial data, while the Arithmetic Average Variability-Weighted method (AAVW) performed better than WA for normal distributions. BDS is flexible for variable distributions and AAVW is only suitable for normal distributions. Because of their simplicity, efficiency, and flexibility, it is expected that these two methods can be programmed into commercial GIS and image analysis packages. 相似文献
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遥感图像多维量化关联规则挖掘 总被引:13,自引:0,他引:13
数据与数据库的爆炸式增长引发了一个十分突出的问题,就是如何高效、智能地将海量的数据转化为有用的信息和知识?近年来,数据挖掘技术的广泛研究正是基于这个目的。初步研究了卫星遥感数据的关联规则挖掘及其在土壤侵蚀和退耕还林上的应用。根据多维空间数据的特点,将遥感数据的属性值划分为不同的块。同时为了充分利用现有的关联规则挖掘的算法,还将划分好的数据转变为事务数据库形式。最后,利用Apriori算法提取了土壤侵蚀强度与坡度、植被覆盖度以及坡耕地之间有意义的关联,为退耕还林还草决策提供有益的支持。 相似文献
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空间信息支持下的江西定南稀土矿区泥石流危险性评价 总被引:1,自引:0,他引:1
江西省定南县是我国离子型稀土矿的主要产区。在稀土开采的同时,产生了大量水土流失,诱发的多处泥石流淹没林地和耕地。运用QuickBird高分辨率遥感信息与3D可视化技术相结合对定南矿区开采面、固体废弃物及其造成的泥石流进行解译,根据泥石流分布特点选取危险性评价因子,建立了评价模型,依据预测结果划分了泥石流的危险性空间分布。预测结果得到遥感影像和野外实际调查的检验,模型在赣南离子型稀土矿区有一定的推广意义。 相似文献
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地理信息系统和遥感结合的现状及发展趋势 总被引:4,自引:0,他引:4
地理信息系统和遥感是支撑现代地理学的两大空间技术工具,近年来它们的结合越来越引起了人们的兴趣与研究。文章着重论述了地理信息系统和遥感结合的现状及其发展趋势,包括地理信息系统和遥感结合的内在原因、方式和存在的主要问题,并介绍了加拿大遥感中心在此方面的新的研完成果。 相似文献
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Probabilistic landslide hazard mapping using GIS and remote sensing data at Boun,Korea 总被引:1,自引:0,他引:1
S. Lee Corresponding author J. Choi K. Min 《International journal of remote sensing》2013,34(11):2037-2052
The aim of this study is to evaluate the hazard of landslides at Boun, Korea, using a Geographic Information System (GIS) and remote sensing. Landslide locations were identified in the Boun area from interpretation of aerial photographs and field surveys. The topographic, soil, forest, geologic, lineament and land cover data were collected, processed and constructed into a spatial database using GIS and remote sensing data. The factors that influence landslide occurrence, such as slope, aspect and curvature of the topography, were calculated from the topographic database. Texture, material, drainage and effective soil thickness were extracted from the soil database, and type, age, diameter and density of timber were extracted from the forest database. The lithology was extracted from the geological database and lineaments were detected from Indian Remote Sensing (IRS) satellite images. The land cover was classified based on the Landsat Thematic Mapper (TM) satellite image. Landslide hazard areas were analysed and mapped, using the landslide-occurrence factors, by the probability–likelihood ratio method. The results of the analysis were verified using actual landslide location data. The validation results showed satisfactory agreement between the hazard map and the existing data on landslide locations. 相似文献
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生态修复水土保持是一项旨在注重依靠大自然的自我修复能力, 在加强预防保护和开展人工辅助治理的前提下, 在较短的时间内实现大面积水土流失初步治理, 区域生态环境逐步恢复, 最终实现人与自然和谐共处的水土保持措施。两当县位于秦岭以南, 属嘉陵江水系, 该县为长江上游实施水土保持生态修复8 个试点县之一。位于该县北部的研究区总面积327. 26 km 2, 是水土流失的主要区域, 2001 至2003 实施生态修复工程。为配合项目区评估利用遥感(RS) 和全球定位系统(GPS) 技术对试验区进行监测与分析。通过项目开始(2001) 和两年后(2003) 的遥感监测、对比分析和结合参考常规观测资料, 对试验区生态环境类型的变化状况和退耕还林还草, 坡改梯田和集水灌溉等辅助措施在生态修复中的作用进行评估。研究结果表明自生态修复工程实施后植被状况有明显变化, 植被覆盖率从86. 50% 增加到98. 04% , 增长11. 54% , 说明研究区生态与环境向逆转方向发展。在实践应用当中, 较高分辨率的卫星资料(TM , SPOT 4, SPOT 5) 可以用于生态修复工程的遥感监测和工程执行的效果评价。 相似文献
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Bing Zhang Xiuping Jia Zhengchao Chen Qingxi Tong 《International journal of remote sensing》2013,34(15):3337-3346
Hyperspectral remote sensing data provide detailed spectral information and are widely used for pixel‐based image classification. However, without considering spatial correlation among neighbouring pixels, a generated thematic map may have a ‘salt‐and‐pepper’ appearance. With the development of the Geographic Information System (GIS), the spatial relationship between a pixel and its neighbours can be recorded readily and used together with remote sensing data. The objective of this study was to integrate hyperspectral data with the GIS for effective thematic mapping. To date, GIS data have been used mainly in field surveys or training field selection for remote sensing data interpretation. Here we propose a patch‐classification based on integration of the GIS with remote sensing data. The classification results obtained by using this method can be easily saved in a vector format as used for GIS files. Computational cost is decreased compared with a pixel‐by‐pixel classification. The issue of how to identify pure or mixed patches is addressed and a three‐level simple and effective checking method is developed. A case study is presented with a hyperspectral data set recorded by the Pushbroom Hyperspectral Imager (PHI) and related GIS data. 相似文献