行星遥感影像目标识别与分类进展

从行星遥感海量数据中对地形地貌特征进行识别和分类,是行星科学研究中的一项重要基础工作。本文综述了自实施月球和深空探测任务以来,国际、国内采用行星影像数据进行地形地貌识别与分类技术的研究进展。首先,从月球、火星以及其他行星探测任务3个方面,对相关的探测任务和获取的影像数据进行简介。然后,在介绍通用目标识别与分类方法研究进展的基础上,分别详细阐述了月球、火星、其他行星影像数据的目标识别与分类研究进展,具体包括：（1）在月球影像目标识别与分类研究进展中,从月球表面环形构造识别,线性构造识别,以及地形分类几个方面展开详述;（2）在火星影像目标识别与分类研究进展中,从构造地貌,风成地貌,水成地貌,其他地貌的识别与地形分类几个方面的研究进展进行详述;（3）其他行星影像目标识别与分类研究进展中,从太阳系的其他类地行星和小行星的影像目标识别与地形分类研究进展进行阐述,其中针对小行星近距离飞越探测、绕飞探测、附着就位探测和表面采样返回等探测方式,分别介绍了对其影像数据的目标识别与地形分类的研究进展。最后,对行星遥感影像目标识别和分类技术的未来发展方向进行了展望和探讨。     

HY-1C/D卫星CZI数据的岛礁浅海水深遥感无控反演能力评估

岛礁浅海水深是海洋重要的基础资料。中国南海岛礁远离大陆,水下现场调查效率低、难度大,难以评估水下地形的长期变化,迫切需要大面积、高频次成像的卫星遥感数据。海洋一号C/D (HY-1C/D)卫星双星组网大大提高了覆盖频次,配置的海岸带成像仪CZI (Coastal Zone Imager)可为岛礁水下探测提供快速的业务化遥感数据服务。为充分发掘两颗卫星的岛礁水深反演能力,本文以中国南海永乐环礁为研究区域,以HY-1C/D CZI多光谱遥感影像为数据源,结合半分析模型和对数比值模型开展了不依赖实测数据的水深反演研究,并与GeoEye-1高分辨率卫星多光谱遥感数据反演结果进行对比。结果表明,HY-1C/D CZI多光谱数据在甘泉岛的水深反演结果与实测数据相比,在0—20 m水深范围内的平均绝对误差分别为1.60 m和1.85 m,平均相对误差分别为22.48%和26.23%;HY-1C/D CZI多光谱数据与基于GeoEye-1数据在甘泉岛的水深反演结果相比,平均绝对偏差分别为1.65 m和1.81 m,平均相对偏差分别为22.33%和23.83%。HY-1C/D CZI与GeoEye-1多...     

主被动光学卫星遥感数据融合浅海水深测量

针对双介质立体摄影测量中水面高程不确定性带来的测深误差,本文提出了主被动光学卫星遥感数据融合浅海水深测量的技术路线,探讨了主动ICESat-2激光测高数据与被动WorldView-3立体像对数据融合的测深模型。首先通过ICESat-2激光测高数据提取海面高程作为WorldView-3立体像对数据水面高程纠正的起算位置,然后利用区域网平差的二次多项式加入适当的水深改正量。在我国南海岛礁开展了主被动光学卫星遥感数据融合进行浅海水深测量试验。结果表明,主被动融合测深模型的均方根误差(RMSE)小于0.70 m,实现了高精度、无实测控制点的浅海水深测量。     

国外遥感技术在烃类微渗漏探测中的应用简介

油气藏中的挥发组份通过上覆地层微裂隙渗漏到地表,形成烃类物质地球化学异常晕。遥感作为一门新技术,已有效地应用到地表油气微渗漏异常的探测。本文主要介绍国外在因烃类微渗漏而造成的油气田地表土壤变化、岩石蚀变和地植物异常等方面的研究现状,以及国外在探索其形成机制方面的进展,并介绍国外石油遥感专家利用各种遥感手段进行烃类微渗漏探测的有效方法,望能达到推动我国石油遥感研究进一步深入与发展的目的。     

辐射沙脊群海域地貌骨征线遥感解译探讨

基于同相水深-辐射关系率定原理,选取环境与灾害监测预报卫星(HJ)遥感影像特征波段,提取辐射沙脊群海区水下地形辐射等值线,利用辐射等值线来勾画地貌骨征线。结果表明,辐射等值线直观上具有地形等高线分布的效果,与等深线的特点相似,能够反映水下地形特点。通过辐射等值线确定辐射沙脊群地貌骨征线,具有一定的实用价值。     

浅海水下地形地貌遥感信息提取与应用

本文根据笔者在我国渤海海峡、闽江口、瓯江口以及珠江口附近海域的遥感实验,讨论由卫星遥感提供的水下地形地貌信息的特征、机理,提出使用信息论和灰色系统论方法分析水深遥感信息传递的过程。以此为依据,建立水深信息提取模型,研究其实用性、精度和效果。实践表明,水深遥感的测量精度没有达到大、中比例尺常规测量的要求。但作为大面积、短周期的宏观分析,特别是遥感图像上显示的海水表层流场特征,对判别浅海水下地形走向和地貌单元,了解其冲刷、沉积作用的动力因素,动态变化等具有十分重要的意义,它成为常规方法的补充手段。对近海的规划、开发,如港湾海水养殖、航道选址、海上工程、海水排污等方面的海水环境分析与宏观评价及监测,具有一定的优势。本文着重讨论了以下三个问题: 1.水下地形地貌遥感的原理与信息特性;2.水深信息提取及灰色系统方法与模糊判别模型分析;3.遥感水下地形地貌的应用与效果分析。     

基于DEM的岷山构造带构造地貌初步研究

以地理信息系统(GIS)为平台,结合构造地貌研究,利用矢量地形数据,构建了岷山构造带数字高程模型(DEM),初步对岷山构造带,特别是岷山断裂带构造地貌特征进行了分析。研究表明,将DEM与GIS技术结合,辅以遥感图像解译和详细野外地质调查,能够直观地进行坡度、坡向以及地形起伏度和高程的统计分析等研究,在构造地貌研究中具有良好的应用前景。     

江苏近海岸水深遥感研究

以江苏近海辐射沙脊群海域为典型研究区,通过实测水深数据和水体光谱测量与分析,发现对应TM3和TM4波段的水体光谱反射率对水深信息敏感,线性相关系数分别达到-0.561和-0.694。结合多光谱遥感信息传输方程所推导出的水深信息对数反演模式,针对本研究区TM4和TM3波段数据所建立的水深预测模式的复相关系数R2为0.4793,对0-15m水深,预测水深和实测水深之间拟合较好。利用TM5波段反射率、出露沙洲反射率以及海水反射率的差异,通过建立掩膜图像,可较有效地对TM遥感图像进行水陆分离,提取TM图像中海水部分,进一步可通过常用的图像处理软件绘制每隔5m的TM水深遥感制图、等深线图。随着高空间、高光谱、高辐射分辨率遥感技术的发展,对浅海水域的水深和水下地形进行遥感探测的技术方法和应用将会不断地深入开展。     

利用激光扫描测量云图提取地图修测数据试验研究

激光扫描测量是近年来发展最为迅速的测量技术之一，目前已在机载地形测绘、机载水深测量、机载防撞探测等众多领域得到应用。利用车载激光扫描测量技术完成地形图修测、三维场景重建、建筑模型制作以及工程测量等任务，是近年来激光扫描测量技术应用研究的一个重要方向。本文概要介绍了以地形图修测应用为目的，开展车载激光扫描测量试验及数据处理研究的基本情况，提出了利用激光扫描云图进行地图修测数据处理与提取的基本流程和方法，通过试验初步验证了激光扫描测量试验系统的测量精度及数据处理与提取方法的可行性。     

海洋测绘技术发展现状

简要介绍了海洋测绘的定义及内涵,从海洋大地测量、海洋导航定位、水深及水下和海岸带地形测量、海洋遥感、海洋水文测量、海底底质探测、海洋工程测量、电子海图和海洋地理信息系统9个方面介绍了海洋测绘技术的发展现状,认为海洋测绘技术正呈现出立体、高精度、高分辨率、高效的信息获取、处理和应用的态势。     

A Study on the Delineation of Coral Reefs in Andaman and Lakshadweep Islands Using RISAT-1 Data

Coral reefs are one of the most diverse of all marine ecosystems and are often referred to as the “rainforests of the sea”. Though they cover less than one per cent of Earth’s surface, they are home to one quarter of all ocean species by providing food and shelter to them. Optical remote sensing has been widely employed for mapping and monitoring coral reefs. But the application of microwave remote sensing has been an alternate domain in this area. This study explores the possibility of utilizing synthetic aperture radar (SAR) data of Radar Imaging Satellite-I, India’s first indigenous microwave satellite to delineate the coral reefs in Andaman and Lakshadweep Islands in the Indian Ocean. The dual polarized data, after reducing the speckle has been classified to delineate the coral reefs in the vicinity of both islands. SAR has a performance comparable with passive optical sensors under favourable conditions of imaging, viz. optimum tidal current and surface winds. The study results are compared with the international coral reef reference map and are found to be highly promising, with an overall accuracy of 98.3% and a Kappa coefficient of 0.944 for fringing reefs in Andaman region. For the atolls in Lakshadweep region, the overall accuracy is found to be 92.99% and the Kappa coefficient is estimated at 0.7377. This study tries to explore a different horizon for microwave remote sensing in coral reef studies. It is seen that, optical and microwave remote sensing can provide a mutually supporting platform in coral reef delineation, in terms of imaging depth as well as climatic conditions.     

面向对象的三亚珊瑚礁底质信息提取

珊瑚礁对于海洋生态环境研究具有重要意义,通过分析珊瑚礁底栖物质的分布及健康状况,可以对珊瑚礁生态环境进行评估。本文提出了一种基于面向对象的图像分类方法,通过试验确定不同地貌的最优分割尺度,其中陆地和深海的最优分割尺度为150,各类底栖物质的最优分割尺度为30。以Sentinel-2A卫星遥感影像为例,提取海南三亚珊瑚礁自然保护区的珊瑚礁底栖物质,并使用混淆矩阵对提取结果进行精度评估。结果表明,底栖物质提取总体分类精度为87.91%,Kappa系数为0.83。面向对象分类方法可有效结合珊瑚礁底栖物质的纹理特征和光谱特征,并充分利用遥感影像不同波段的组合特性,可为三亚珊瑚礁保护管理提供方法支撑。     

Creating Landscape-Scale Maps of Coral Reef Cover for Marine Reserve Management from High-Resolution Multispectral Remote Sensing

New methods are needed for the study of coral reefs, as they are changing rapidly. Satellite remote sensing has become a common method for benthic mapping with advances in satellites and sensors and as methods are devised to account for atmospheric and water-column effects. Images from the QuickBird satellite have proven useful in reef mapping. Sand was distinguished from coral with an overall accuracy of 75% on the shallow reef off of the Caribbean island of Bonaire. Coral and sand had user accuracies of 50% and 90%, respectively. Increased samples of field-collected data would further increase the accuracies of such classifications.     

Towards new applications of underwater photogrammetry for investigating coral reef morphology and habitat complexity in the Myeik Archipelago,Myanmar

Photogrammetry represents a non-destructive, cost-effective tool for coral reef monitoring, able to integrate traditional remote sensing techniques and support researchers’ work. However, its application to submerged habitats is still in early stage. We present new ways to employ Structure from Motion techniques to infer properties of reef habitats. In particular, we propose the use of Digital Surface Models and Digital Terrain Models for assessing coral colonies extension and height and discriminating between seabed and coral cover. Such information can be coupled with digital rugosity estimates to improve habitat characterization. DTM, DSM and orthophotos were derived and used to compute a series of metrics like coral morphologies, reef topography, coral cover and structural complexity. We show the potentialities offered by underwater photogrammetry and derived products to provide useful basic information for marine habitat mapping, opening the possibility to extend these methods for large-scale assessment and monitoring of coral reefs.     

遥感技术在震后建筑物损毁检测中的应用

建筑物损毁信息提取作为震后损失评估的重要内容，对于及时了解灾情、开展灾害应急响应及灾后恢复重建等具有重要意义。近年来，多平台遥感技术和高分辨率遥感技术的飞速发展为建筑物损毁信息的精确提取带来新的发展机遇。在介绍建筑物损毁基本特征和分级标准的基础上，总结了目前国内外遥感技术在建筑物损毁检测方面的常见方法，包括基于震后单时相的提取方法、灾前灾后的变化检测方法以及融合多源数据的建筑物损毁信息检测方法，并分析了各种方法本身的局限性与不足。结合目前遥感领域的前沿技术，探讨了如何基于高分辨率遥感技术、合成孔径雷达技术、机载激光雷达技术以及倾斜摄影技术实现震后建筑物损毁信息的提取。     

Shoreline and coral reef ecosystem changes in gulf of Mannar, Southeast coast of India

Changes in shoreline, coral reef and seafloor have been mapped using remote sensing satellite data of IRS LISS-III (1998), IRS LISS-II (1988), Survey of India Topographic sheet (1969), Naval Hydrographic Chart (NHO) 1975 and bathymetry data (1999) with ARC-INFO and ARC-VIEW GIS. The analysis of multi-date shoreline maps showed that 4.34 and 23.49 km2 of the mainland coast and 4.14 and 3.31 km² areas of island coast have been eroded and accreted, respectively, in the Gulf of Mannar. The analysis of multi-date coral reef maps showed that 25.52 km² of reef area and 2.16 km² of reef vegetation in Gulf of Mannar have been lost over a period of ten years. The analysis of multi-date bathymetry data indicates that the depth of seafloor has decreased along the coast and around the islands in the study area. The average reduction of depth in seafloor has been estimated as 0.51m over a period of twenty four years. The increased suspended sediment concentration due to coastal and island erosion, and raised reef due to emerging of coast by tectonic movement are responsible for coral reef degradation in the Gulf of Mannar. Validation by ground truth has confirmed these results.     

烃类微渗漏晕及其信息提取

本文在综合研究近些年来国内外遥感直接找油这一领域研究成果的基础上，系统地给出烃和烃类微渗漏晕波谱特性以及遥感影像烃类微渗漏信息的计算机提取方法，它们分别是遥感技术直接找油的基础和关键。     

Eco-Geomorphological zonation of The Bangaram Reef, Lakshadweep

Coral reefs, which are known for rich biological diversity and productivity, are being threatened throughout the world by various natural and anthropogenic activities. The present study concentrates on establishing methodology to zone the geo-morphological and ecological zones of the Bangaram reef (of atoll type), Lakshadweep islands, using remotely sensed data and adequately supported by field data. Classification system has been evolved to zone the reefs. Comparative studies have also been carried out using image processing techniques in order to establish the suitable technique for studying the Indian reefs. The IRS LISS III images representing three different tidal conditions of the period 1998-2000 were analyzed. The unsupervised classification of both the raw images as well as principal component images gave similar information. The classified product was subjected to contextual editing. Misclassification among various classes was found to increase with the increase in the depth of the water column present over the reef. The zones identified on the image are central deep lagoon, reef knolls (rising steeply from the central deep lagoon floor), reef edge, reef platform, coralline shelf, broad shallow sandy-bottomed lagoon, beach and two islets. The zonation has helped in getting information on the presence of live corals on the Bangaram reef. This kind of study is a valuable input in assessing the health of the reefs and its diversity.     

A global inventory of coral reef stressors based on satellite observed nighttime lights

In this article, we present a satellite-based approach to gather information about the threat to coral reefs worldwide. Three chosen reef stressors – development, gas flaring and heavily lit fishing boat activity – are analysed using nighttime lights data derived from the Defense Meteorological Satellite Program (DMSP) produced at the National Oceanic & Atmospheric Administration, National Geophysical Data Center (NOAA/NGDC). Nighttime lights represent a direct threat to coral reef ecosystems and are an excellent proxy measure for associated human-caused stressors. A lights proximity index (LPI) is calculated, measuring the distance of coral reef sites to each of the stressors and incorporating the stressor's intensity. Colourized maps visualize the results on a global scale. Area rankings clarify the effects of artificial night lighting on coral reefs on a regional scale. The results should be very useful for reef managers and for state administrations to implement coral reef conservation projects and for the scientific world to conduct further research.     

“遥感原理与应用”实践教学内容设计与思考

遥感类课程可以大致分为遥感专业类和遥感应用类。无论哪类课程,遥感实践教学都是其中一个非常重要的内容。本文针对遥感应用类课程中实验课程的内容设计进行探讨,在调研了国内外遥感应用类课程实验内容设计的基础上,对比分析了国内外遥感应用类课程实验教学内容设计特点。结合笔者从事"遥感原理与应用"课程教学中的一些探索与思考,提出了在提高实践教学环节质量中需要处理好的几个关系。