Predictive vegetation mapping approach based on spectral data, DEM and generalized additive models     

Chuangye Song  Chong Huang  Huiming Liu 《中国地理科学(英文版)》2013,23(3):331-343

This study aims to provide a predictive vegetation mapping approach based on the spectral data, DEM and Generalized Additive Models (GAMs). GAMs were used as a prediction tool to describe the relationship between vegetation and environmental variables, as well as spectral variables. Based on the fitted GAMs model, probability map of species occurrence was generated and then vegetation type of each grid was defined according to the probability of species occurrence. Deviance analysis was employed to test the goodness of curve fitting and drop contribution calculation was used to evaluate the contribution of each predictor in the fitted GAMs models. Area under curve (AUC) of Receiver Operating Characteristic (ROC) curve was employed to assess the results maps of probability. The results showed that: 1) AUC values of the fitted GAMs models are very high which proves that integrating spectral data and environmental variables based on the GAMs is a feasible way to map the vegetation. 2) Prediction accuracy varies with plant community, and community with dense cover is better predicted than sparse plant community. 3) Both spectral variables and environmental variables play an important role in mapping the vegetation. However, the contribution of the same predictor in the GAMs models for different plant communities is different. 4) Insufficient resolution of spectral data, environmental data and confounding effects of land use and other variables which are not closely related to the environmental conditions are the major causes of imprecision.  相似文献   

Geology, tectonics, and the 2002-2003 eruption of the Semeru volcano, Indonesia: Interpreted from high-spatial resolution satellite imagery     

Akhmad SolikhinJean-Claude Thouret  Avijit GuptaAndy J.L. Harris  Soo Chin Liew 《Geomorphology》2012,138(1):364-379

The paper illustrates the application of high-spatial resolution satellite images in interpreting volcanic structures and eruption impacts in the Tengger-Semeru massif in east Java, Indonesia. We use high-spatial resolution images (IKONOS and SPOT 5) and aerial photos in order to analyze the structures of Semeru volcano and map the deposits. Geological and tectonic mapping is based on two DEMs and on the interpretation of aerial photos and four SPOT and IKONOS optical satellite images acquired between 1996 and 2002. We also compared two thermal Surface Kinetic Temperature ASTER images before and after the 2002-2003 eruption in order to delineate and evaluate the impacts of the pyroclastic density currents. Semeru's principal structural features are probably due to the tectonic setting of the volcano. A structural map of the Tengger-Semeru massif shows four groups of faults orientated N40, N160, N75, and N105 to N140. Conspicuous structures, such as the SE-trending horseshoe-shaped scar on Semeru's summit cone, coincide with the N160-trending faults. The direction of minor scars on the east flank parallels the first and second groups of faults. The Semeru composite cone hosts the currently active Jonggring-Seloko vent. This is located on, and buttressed against, the Mahameru edifice at the head of a large scar that may reflect a failure plane at shallow depth. Dipping 35° towards the SE, this failure plane may correspond to a weak basal layer of weathered volcaniclastic rocks of Tertiary age. We suggest that the deformation pattern of Semeru and its large scar may be induced by flank spreading over the weak basal layer of the volcano. It is therefore necessary to consider the potential for flank and summit collapse in the future. The last major eruption took place in December 2002-January 2003, and involved emplacement of block-and-ash flows. We have used the 2003 ASTER Surface Kinetic Temperature image to map the 2002-2003 pyroclastic density current deposits. We have also compared two 10 m-pixel images acquired before and after the event to describe the extent and impact of an estimated volume of 5.45 × 10⁶ m³ of block-and-ash flow deposits. An ash-rich pyroclastic surge escaped from one of the valley-confined block-and ash flows at 5 to 8 km distance from the crater and swept across the forest and tilled land on the SW side of the Bang River Valley. Downvalley, the temperature of the pyroclastic surge decreased and a mud-rich deposit coated the banks of the Bang River Valley. Thus, hazard mitigation at Semeru should combine: (1) continuous monitoring of the eruptive activity through an early-warning system, and (2) continuous remote sensing of the morphological changes in the drainage system due to the impact of frequent pyroclastic density currents and lahars.  相似文献   

Interpretation of earthquake-induced landslides triggered by the 12 May 2008, M7.9 Wenchuan earthquake in the Beichuan area, Sichuan Province, China using satellite imagery and Google Earth   总被引：5，自引：2，他引：3  

H. P. Sato  E. L. Harp 《Landslides》2009,6(2):153-159

The 12 May 2008 M7.9 Wenchuan earthquake in the People’s Republic of China represented a unique opportunity for the international community to use commonly available GIS (Geographic Information System) tools, like Google Earth (GE), to rapidly evaluate and assess landslide hazards triggered by the destructive earthquake and its aftershocks. In order to map earthquake-triggered landslides, we provide details on the applicability and limitations of publicly available 3-day-post- and pre-earthquake imagery provided by GE from the FORMOSAT-2 (formerly ROCSAT-2; Republic of China Satellite 2). We interpreted landslides on the 8-m-resolution FORMOSAT-2 image by GE; as a result, 257 large landslides were mapped with the highest concentration along the Beichuan fault. An estimated density of 0.3 landslides/km² represents a minimum bound on density given the resolution of available imagery; higher resolution data would have identified more landslides. This is a preliminary study, and further study is needed to understand the landslide characteristics in detail. Although it is best to obtain landslide locations and measurements from satellite imagery having high resolution, it was found that GE is an effective and rapid reconnaissance tool.  相似文献   

利用SPOT卫星遥感影像测绘1：50000地形图的探讨   总被引：5，自引：0，他引：5  

蒋红兵 《四川测绘》2001,24(3):115-116

目前，高分辨率的卫星遥感影像逐步商业化，国内外不断把卫星遥感影像应用于测绘领域。本文主要分析，研究利用SPOT卫星遥感影像测绘1：50000地形图的地理精度和地物判断能力，认为在山地，高山地地区基本上可以利用SPOT卫星遥感影像测绘1：50000地形图。  相似文献   

Hydrological mapping from SPOT imagery     

Abdalla Elsadig Ali 《地球表面变化过程与地形》1991,16(2):173-180

Four SPOT images, one panchromatic and three multispectral, were studied to evaluate their usefulness for hydrological mapping in an arid environment. Simple visual methods of interpretation were used to plot the drainage network independently from each test image. The results were compared with the drainage network shown on the topographic map of the area. Results show that with the panchromatic image, over 90 per cent of the map content could be discerned, identified, and plotted. The accuracy of plotting the drainage system from the multispectral images seems to depend on the season in which data had been acquired. However, in all cases, the success rate is not less than 70 per cent. Comparison with Landsat Thematic Mapper (TM) imagery showed that SPOT system is superior in hydrological mapping.  相似文献   

秦淮河丘陵地区土地利用遥感信息提取及制图   总被引：15，自引：1，他引：15  

王周龙  冯学智  刘晓枚  都金康 《遥感学报》2003,7(2):131-135

着重论述了使用SPOT卫星遥感图像提取土地利用专题信息的技术与方法。利用数字地形模型（DEM）派生的坡度、坡向等辅助信息，对遥感影像的光谱特征空间进行扩展，建立基于知识的统计分析扩展模型，对不同参数的分类结果进行评价。研究结果表明，该方法能有效地提取SPOT星遥感土地利用专题信息，特别适合我国南方丘陵地区土地利用遥感信息提取。同时，通过地物分层分类信息提取方法和遥感影像数据融合技术，编制了研究区土地利用现状图。  相似文献   

SPOT4-VEGETATION中国西北地区土地覆盖制图与验证   总被引：13，自引：0，他引：13  

卢玲  李新  董庆罕  Else Swinnen  Frank Veroustraete  王建华  王一谋 《遥感学报》2003,7(3):214-220

利用SPOT4 VEGETATION的遥感数据产品生成的NDVI与NDWI植被指数时间序列图像集 ,通过ISODATA非监督分类方法 ,编制中国西北地区土地覆盖图。以TM影像人工解译结果作为真实值 ,通过对西北五省共计 47个均匀分布且异质性强的 2 5km× 2 5km样本区内的土地覆盖类型及其面积进行统计分析 ,修正了SPOT4 VEGETATION的土地覆盖分类系统 ,建立了各省验证结果的样本统计直方图并计算其回归系数。结果表明SPOT4 VEGETATION中国西北地区土地覆盖图在总体上具有较高的准确性。影响遥感数据自动分类精度 ,造成土地覆盖误判的原因主要来源于两个方面 :即异物同谱和混合像元问题。对于前者通过叠加各种辅助数据如DEM等可以降低误判的机率 ;对于后者运用混合像元分解的各种算法可以提高分类精度  相似文献   

A Multiscale Object-Specific Approach to Digital Change Detection   总被引：1，自引：0，他引：1  

Ola Hall  Geoffrey J. Hay 《International Journal of Applied Earth Observation and Geoinformation》2003,4(4):311-327

Landscape spatial pattern is dependent not only on interacting physiographic and physiological processes, but also on the temporal and spatial scales at which the resulting patterns are assessed. To detect significant spatial changes occurring through space and time three fundamental components are required. First, a multiscale dataset must be generated. Second, a change detection framework must be applied to the multiscale dataset. Third, a procedure must be developed to delineate individual image-objects and identify them as they change through scale. In this paper, we introduce an object-specific multiscale digital change detection approach. This approach incorporates multitemporal SPOT Panchromatic (Pan) data, object-specific analysis (OSA), object-specific up-scaling (OSU), marker-controlled watershed segmentation (MCS) and image differencing change detection. By applying this framework to SPOT Pan data, image-objects that have changed between registration dates can be identified and delineated at their characteristic scale of expression. Results illustrate that this approach has the ability to automatically detect changes at multiple scales as well as suppress sensor related noise. This study was conducted in the forest region of the Örebro Administrative Province, Sweden.  相似文献   

IRS-P6与SPOT-5卫星影像在土地利用动态遥感监测中应用的比较   总被引：2，自引：1，他引：2  

吴海平  刘顺喜  史良树 《国土资源遥感》2005,(4):42-45

IRS-P6卫星影像的最高空间分辨率是5.8 m,在土地利用动态遥感监测领域中有较大的应用潜力,本研究通过与2.5 m分辨率的SPOT-5卫星影像在成图比例尺、响应图斑大小、地类可解度和信息提取精度等方面进行比较试验,结果表明,IRS-P6卫星影像可以制作1︰2.5万和1︰5万中等比例尺的图件,更新或辅助更新1︰2.5万与1︰5万的土地利用现状图.在土地利用动态遥感监测中,可以作为另外一种数据源与单一的SPOT数据源进行互补,使之更快捷地服务于国土资源管理工作.  相似文献   

Spot Revisited: Accuracy Assessment, Dem Generation and Validation from Stereo Spot 5 Hrg Images     

Gürcan  Büyüksalih  Güven  Koçak  Hüseyin  Topan  Murat  Oruç  Aycan  Marangoz 《The Photogrammetric Record》2005,20(110):130-146

SPOT 5 HRG Level 1A and 1B stereo scenes covering Zonguldak testfield in north-west Turkey have been analysed. They comprise the left and right image components with base to height ratio of 0·54. The pixel size on the ground is 5 m. The bundle orientation was executed by the PCI Geomatica V9.1.4 software package and resulted in 3D geopositioning to sub-pixel accuracies in each axis provided that at least six control points were used in the computation. Root mean square error (rmse) values and vectors of residual errors for Levels 1A and 1B are similar, even for different control and check point configurations. Based on the scene orientation, Level 1A and 1B digital elevation models (DEMs) of the testfield have been determined by automatic matching and validated by the reference DEM digitised from the 1:25 000 scale topographic maps, interferometric DEMs from Shuttle Radar Topography Mission (SRTM) X- and C-band SAR data and the GPS profiles measured along the main roads in the testfield. Although the accuracies of reference data-sets are too similar to the generated SPOT DEMs, these are the only high quality reference materials available in this area. Sub-pixel height accuracy was indicated by the comparison with profile points. However, they are in favourable locations where matching is always successful, so such a result may give a biased measure of the accuracy of the corresponding DEMs.  相似文献