Shoreline change analysis along the coast between Kanyakumari and Tuticorin of India using remote sensing and GIS

Shoreline is one of the rapidly changing landform in coastal area. So, accurate detection and frequent monitoring of shorelines are very essential to understand the coastal processes and dynamics of various coastal features. The present study is to investigate the shoreline changes along the coast between Kanyakumari and Tuticorin of south India, where hydrodynamic and morphologic changes occur continuously after the December 2004 tsunami. Multi-date satellite data of Indian Remote Sensing (IRS) satellites (1999, 2000, 2003, 2005, and 2006) are used to extract the shorelines. The satellite data is processed by using the ERDAS IMAGINE 9.1 software and analyzed by ArcGIS 9.2 workstation. The different shoreline change maps are developed and the changes are analyzed with the shoreline obtained from the Survey of India Toposheets (1969). The present study indicates that accretion was predominant along the study area during the period 1969–1999. But recently (from 1999 onwards), most of the coastal areas have experienced erosion. The study also indicates the reversal of shoreline modifications in some coastal zones. The coastal areas along the headlands have experienced both erosion and accretion. Though the coastal erosion is due to both natural and anthropogenic activities, the coastal zones where sand is mined have more impacts and relatively more rate of erosion than that of other zones. Improper and in-sustainable sand mining leads to severe erosion problem along this area. So the concept of sustainable management should be interpreted in the management of the near-shore coastal sand mining industry.     

新疆苇湖梁煤矿塌陷区遥感监测研究

苇湖梁煤矿已有50多年的开采历史, 长期的地下开采造成了严重的地面塌陷。本文将新疆苇湖梁煤矿塌陷区作为研究区, 以2013年的IKONOS高分遥感影像为主要数据源, 以ArcGIS为支撑平台, 采用人机交互的解译方法对塌陷区的相关信息进行提取, 结合实地调查验证的方法, 分析研究区内地质灾害的特征。通过遥感调查发现: 研究区内发育规模较大、位于塌陷区周围的拉伸区的地裂缝约有64条;塌陷坑(群)约有94个, 主要分布于南北塌陷槽及两侧;塌陷回填区总面积达0.92 km², 并在回填区发现了3个新塌陷坑。本文充分发挥了遥感技术宏观性强、速度快的特点, 调查结果反映了塌陷区灾害的实际情况。     

基于RS、GIS集成技术的黄河三角洲海岸线变迁研究

海岸线变迁是黄河三角洲地区重大环境地质问题之一。本文应用RS、GIS集成技术,通过对黄河三角洲海岸线钓口段、黄河港段和河口段3个区段28年(1976—2004年)MSS和TM系列影像数据的分析研究,发现了1976年黄河人工改道后三角洲海岸线变迁的总体规律与趋势,即北部钓口地区不断侵蚀、后退,东北部黄河港地区基本稳定,南部河口地区不断淤积、前进。这一发现对该区域的资源开发、环境保护等具有重要的指导意义。     

国道214线西藏段地质灾害遥感调查与评价

同道214线西藏段位于西藏东南部，地形地貌复杂，构造发育，是地质灾害的多发地区。利用以往资料、ETM遥感影像解译及野外调查，在公路沿线圈定出崩塌76处、滑坡26处、泥石流沟101条，并对这些地质灾害的发育状况和危害特征进行了评价。     

Landsat-TM遥感影像岸线变迁解译研究--以九龙江河口地区为例

利用遥感与GIS技术相合的手段，在分析九龙江河口地区地物波谱的基础上，对研究区两期遥感影像（1986年6月与2000年5月的陆地卫星Landsat—TM资料）进行解译和岸线提取。通过与20世纪70年代的地形图进行对比分析，发现九龙江北、西溪过河口大沙洲后分成北、中、南3个支流入海，其中以浒茂洲两侧的支流岸线变化最大；海门岛至口门段河口两侧岸线也有不同程度的变化；厦门西港海区是本研究区岸线变化最大的区域。文章最后对岸线变迁和河口淤积进行了初步的分析。     

四川省矿山地质环境调查与评价

文章以攀枝花市钒钛磁铁矿区、龙门山中段煤磷矿区、新康石棉矿区为例，从矿山地质环境概况，矿山主要地质灾害，矿山地质环境分区等入手，全面分析了四川省矿山地质环境现状及开发利用对生态地质环境的影响和破坏，存在的主要环境地质问题及危害。并提出了矿山生态地质环境恢复与重建的建议。     

Groundwater study using remote sensing and geographic information systems (GIS) in the central highlands of Eritrea

Remote sensing, evaluation of digital elevation models (DEM), geographic information systems (GIS) and fieldwork techniques were combined to study the groundwater conditions in Eritrea. Remote sensing data were interpreted to produce lithological and lineament maps. DEM was used for lineament and geomorphologic mapping. Field studies permitted the study of structures and correlated them with lineament interpretations. Hydrogeological setting of springs and wells were investigated in the field, from well logs and pumping test data. All thematic layers were integrated and analysed in a GIS. Results show that groundwater occurrence is controlled by lithology, structures and landforms. Highest yields occur in basaltic rocks and are due to primary and secondary porosities. High yielding wells and springs are often related to large lineaments, lineament intersections and corresponding structural features. In metamorphic and igneous intrusive rocks with rugged landforms, groundwater occurs mainly in drainage channels with valley fill deposits. Zones of very good groundwater potential are characteristic for basaltic layers overlying lateritized crystalline rocks, flat topography with dense lineaments and structurally controlled drainage channels with valley fill deposits. The overall results demonstrate that the use of remote sensing and GIS provide potentially powerful tools to study groundwater resources and design a suitable exploration plan.An erratum to this article can be found at     

Groundwater study using remote sensing and geographic information systems (GIS) in the central highlands of Eritrea

Remote sensing, evaluation of digital elevation models (DEM), geographic information systems (GIS) and fieldwork techniques were combined to study the groundwater conditions in Eritrea. Remote sensing data were interpreted to produce lithological and lineament maps. DEM was used for lineament and geomorphologic mapping. Field studies permitted the study of structures and correlated them with lineament interpretations. Hydrogeological setting of springs and wells were investigated in the field, from well logs and pumping test data. All thematic layers were integrated and analysed in a GIS. Results show that groundwater occurrence is controlled by lithology, structures and landforms. Highest yields occur in basaltic rocks and are due to primary and secondary porosities. High yielding wells and springs are often related to large lineaments, lineament intersections and corresponding structural features. In metamorphic and igneous intrusive rocks with rugged landforms, groundwater occurs mainly in drainage channels with valley fill deposits. Zones of very good groundwater potential are characteristic for basaltic layers overlying lateritized crystalline rocks, flat topography with dense lineaments and structurally controlled drainage channels with valley fill deposits. The overall results demonstrate that the use of remote sensing and GIS provide potentially powerful tools to study groundwater resources and design a suitable exploration plan.The online version of the original article can be found at     

Characterising the distribution of near-shore submarine groundwater discharge along a coastline using 222Rn and electrical conductivity

The spatial and temporal distribution of near-shore fresh submarine groundwater discharge (SGD) was characterised from the coastal aquifers of the Willunga Basin, South Australia, an extensive aquifer system that supports an important viticultural region. Measurements of electrical conductivity (EC) and ²²²Rn (radon) activity were collected at 19 sites along the coastline during the Southern Hemisphere spring (2011) and summer (2013). At each site, samples were collected from the surf zone as well asporewater from beach sediment in the intertidal zone. Surf-zone radon activity ranged from <5 to 70mBq L^–1, and intertidal porewater radon ranged over two orders of magnitude (220–36 940 mBq L^–1) along the Willunga Basin coastline during both surveys. Overall, surf-zone and porewater EC was lower in the spring 2011 survey than in the summer 2013 survey. Porewater EC was similar to that of coastal water at most sites along the coastline, except at three sites where porewater EC was found to be lower than coastal water during both surveys, and three sites where evaporated seawater was observed in the summer survey. Based on the patterns in radon and EC along the coastline, two sites of localised fresh SGD were identified, in addition to a groundwater spring that is known to discharge to the coast. The results indicate that near-shore fresh SGD occurs as localised seeps rather than diffuse seepage along the entire coastline. The apparent absence of groundwater discharge at most locations is also consistent with current evidence suggesting that extensive groundwater pumping within the basin has resulted in seawater intrusion across much of the coastline. These observations also suggest that previous studies are likely to have over-estimated SGD rates from the Willunga Basin because they assumed that SGD occurred along the entire coastline.     

无人机遥感在西气东输管道地质灾害调查中的应用

阐述了应用无人机遥感进行地质灾害调查的关键技术与方法,介绍了无人机遥感系统的组成,通过对外业航拍、正射影像生成、影像判读等技术要点的研究,以及航拍成果的精度检验与分析,论证了采用该系统获取的航空影像进行地质灾害调查的可行性。     

Compression of remote sensing data using second-generation wavelets: a review

Wavelet-based methods have been widely used for compression of remotely sensed images and data. Recently, second generation of wavelets which is based on a method called lifting has proven to be more effective than traditional wavelets as it provides lossless compression, lowers the memory usage, and is computationally faster. This study explores the literature related to applying second-generation wavelets for the compression of remote sensing data. Nevertheless, in order to compare the results of two wavelet types, some applications of traditional wavelets are also presented.     

基于物理模型的被动微波遥感反演土壤水分

利用土壤水分和海洋盐度(SMOS)卫星进行土壤水分反演的算法中,对地表发射率的描述仍采用半经验Q/H模型,该模型描述地表粗糙度对有效发射率在V和H极化下影响相同.基于微波散射理论模型-高级积分方程模型(AIEM)建立了一个针对SMOS传感器的参数配置,包含各种地表粗糙度和介电特性的裸露地表辐射模拟数据库,发展了L波段多角度地表辐射参数化模型.在此基础上,利用SMOS多角度双极化特点,建立了土壤水分反演算法.该算法可以消除粗糙度对土壤水分反演的影响,同时最小化反演过程中辅助信息引入带来影响.反演算法通过美国农业部提供的L波段多角度地基辐射计数据(BARC)进行验证,在20°~50°入射角,土壤水分反演精度在4%左右.     

Change detection of the coastal zone east of the Nile Delta using remote sensing

The coastal zone of the Nile Delta is a promising area for energy resources and industrial activities. It also contains important wetland ecosystems. This coastal area witnessed several changes during the last century. A set of four satellite images from the multi-spectral scanner (MSS), thematic mapper (TM) and Systeme Pour l’Observation de la Terre (SPOT) sensors were utilized in order to estimate the spatio-temporal changes that occurred in the coastal zone between Damietta Nile branch and Port-Said between 1973 and 2007. Image processing applied in this study included geometric rectification; atmospheric correction; on-screen shoreline digitizing of the 1973 (MSS) and 2007 (SPOT) images for tracking the shoreline position between Damietta promontory and Port-Said; and water index approach for quantifying Manzala lagoon surface area change using 1973 (MSS), 1984 (TM) and 2003 (TM) images. Results showed that coastal erosion was severe near Damietta promontory and decreased eastward, however, accretion was observed near Port-Said. About 50% of the coastal strip was under erosion and 13% was under accretion. In addition, a remarkable decline (34.5%) of the Manzala lagoon surface area was estimated. These changes were attributed mainly to the control of the River Nile flooding and the land use change by anthropogenic activities.     

Understanding the tectonic behaviour of the Shillong Plateau,India using remote sensing data

Shillong Plateau in India is tectonically and geologically interesting entity in the subducted front of Indian Plate below Burmese Plate to the southeast and Tibetan Plate to the north and associated with thrusts and shears along the plate boundaries. Horse-tail geometry in the foothills of the Arunachal Himalaya, east of Jia Bhareli river, associated with south-convex foothill ranges in the eastern Himalaya and exactly similar structural geometry in the eastern part of Shillong Plateau in Meghalaya seems to develop due to resistance received by the plateau in its eastward journey. Wide separation of Karbi Anglong Plateau and Shillong Plateau to the southeast as compared to northwestern part defines the shape of Kopili graben. Low seismic activity in southeastern part of Shillong Plateau might be related to stress released field generated by its clockwise rotation. Satellite derived images and digital elevation data from Landsat ETM+ and SRTM data shows that the central part of Shillong Plateau possesses young topography with strong structural fabrics along with relatively high topography aligning NE-SW following Kolkota-Pabna-Mymansingh High and if extended passes through western part of Arunachal Pradesh in eastern Himalayas. This alignment has been observed in Precambrian gneissic complex west of the Proterozoic intracratonic Shillong Basin. The epicentral plot for the period 1918 to 2009 shows their high concentration within the Shillong Plateau aligning along this trend. The active geodynamics of Shillong Plateau is reflected in its seismic activity pattern in relation with the structural fabrics, northward migration of the Brahmaputra in the north front of the Plateau and by shrinking pattern of Chandubi Lake in the Kulsi river catchment, a north-flowing tributary of the Brahmaputra in the north-central part of the plateau.     

应用遥感技术研究吉林省的地质灾害

利用遥感技术对吉林省地质灾害进行了较详细的解译，共解译出128处滑坡，其中软岩滑坡66处，碎石滑坡50处，硬岩滑坡12处，解译出规模较大的泥石流126处，崩塌4处，沼泽化严重的地带百余处，对土地沙化，土地盐碱化，水土流失，水库淤积及河流改道等也做了较详细的解译，提出了各种地质灾害的形成条件及影响因素，滑坡，泥石流、崩塌的形成与地形坡度，岩土体类型，水网密度等关系密切，地震也可诱导滑坡产生，水土流失，水库淤积主要与地形坡度、植被覆盖率，岩土体类型及水网密度有关，河流改道是第四纪地壳运动的区域性断块隆起和凹陷，或断裂的相对升降运动，或地壳上升运动的差异性所致，土地沼泽化、土化盐碱化主要形成于排水不畅地带，对不同类型的地质灾害提出了相应的防治对策。