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1.
This paper describes a remote sensing approach used to monitor temporal land use/cover (LULC) changes in Cukurova, an extensive coastal plain in the southeast Mediterranean coast of Turkey. The area has varied terrain ranging from low-lying alluvial deposits to rocky hills and mountains characterized by limestone outcrops. The ecological and economic importance of the area can be attributed to the existence of important coastal ecosystems (e.g., wetlands and sand dunes) and a wide range of industries located along the eastern coast. Temporal changes in the coastal landscape between 1984 and 2000 were evaluated using digital interpretation of remotely sensed satellite data. Pairwise comparison methods were used to quantify changes from 1984 to 1993 and 1993 to 2000 using multitemporal Landsat TM and ETM+ images, acquired in 1984, 1993, and 2000, respectively. Total change area was 2448 ha from 1984 to 1993 and increased more than twofold, to 6072 ha from 1993 to 2000. Change trends were determined using the information provided from individual change detection outputs of different periods. The most prominent changes were estimated to have occurred in agriculture, urban, and natural vegetation cover. Agriculture has increasingly grown over marginal areas, whereas urban development occurred at the expense of prime croplands across both time steps.  相似文献   

2.
Remote Sensing of Landscape-Level Coastal Environmental Indicators   总被引:5,自引:1,他引:4  
Advances in technology and decreases in cost are making remote sensing (RS) and geographic information systems (GIS) practical and attractive for use in coastal resource management. They are also allowing researchers and managers to take a broader view of ecological patterns and processes. Landscape-level environmental indicators that can be detected by Landsat Thematic Mapper (TM) and other remote sensors are available to provide quantitative estimates of coastal and estuarine habitat conditions and trends. Such indicators include watershed land cover, riparian buffers, shoreline and wetland changes, among others. With the launch of Landsat 7, the cost of TM imagery has dropped by nearly a factor of 10, decreasing the cost of monitoring large coastal areas and estuaries. New satellites, carrying sensors with much finer spatial (1-5 m) and spectral (200 narrow bands) resolutions are being launched, providing a capability to more accurately detect changes in coastal habitat and wetland health. Advances in the application of GIS help incorporate ancillary data layers to improve the accuracy of satellite land-cover classification. When these techniques for generating, organizing, storing, and analyzing spatial information are combined with mathematical models, coastal planners and managers have a means for assessing the impacts of alternative management practices.  相似文献   

3.
秦皇岛海岸侵蚀动态研究   总被引:2,自引:0,他引:2  
利用不同时期的地形图、遥感图片对比,并选取典型海岸岸滩监测剖面实测数据,对海岸侵蚀现状进行了分析和定量计算。分析结果显示,秦皇岛海岸全线处于侵蚀状态,平均蚀退率1.5~4 m/a,根据蚀退率可将秦皇岛海岸划分为严重侵蚀、强侵蚀、侵蚀、微侵蚀、稳定5种岸线侵蚀类型。  相似文献   

4.
Sustainable Management for the Eastern Mediterranean Coast of Turkey   总被引:2,自引:0,他引:2  
The objective of this article is to propose a program for the integrated coastal zone management that is required to stimulate and guide sustainable development of the Mediterranean coastal zone of Turkey. Improved data collection, quality control, analysis, and data management will provide a firm basis for future scientific understanding of the East Mediterranean coast of Turkey and will support long-term management. Various innovative procedures were proposed for a promising ecosystem-based approach to manage coastal wetlands in the Mediterranean: remote data acquisition with new technologies; environmental quality monitoring program that will provide a baseline for monitoring; linking a Geographic Information System (GIS) with natural resource management decision routines in the context of operational wetlands, fisheries, tourism management system; environmental sensitivity analysis to ensure that permitted developments are environmentally sustainable; and use of natural species to restore the wetlands and coastal dunes and sustain the system processes. The proposed management scheme will benefit the scientific community in the Mediterranean and the management/planning community in Eastern Turkey.  相似文献   

5.
Coastal subsystems formed by interaction of various processes, impacted by natural hazards like tsunami and storms, pose irreversible morphological changes. Vellar estuary, located on the southeast coast of India, with huge sand dunes (of 3-6m height and spread to 560ha) and barrier islands, has undergone extensive morphological changes due to the giant Indian Ocean tsunami that occurred on 26th December 2004. The damage caused by the tsunami has been quantified using extensive field data collected during pre- and post-tsunami periods through Real Time Kinematic GPS (for mapping coastal features and beach profiles) and Geographic Information System (GIS) couple. The tsunami with a wave height as high as 4m not only inundated the entire coastal land up to a maximum of 2km but also eroded the sand dunes and deposited the eroded material at the inlet, which ultimately formed as a vast tidal flat spread over 31ha. The estuary has suffered immensely due to the tsunami especially in terms of (i) loss of natural protection barriers (sand dunes), which made this coastal area more vulnerable to storm attack, and (ii) shallowness of inlet creating hindrance to navigation of fishing vessels. Based on the observations made at Vellar coast and past recovery experiences of tsunami/hurricanes elsewhere in the world, we contend that the morphological loss might take at least two annual cycles to regain its original form and the rebuilding of sand dunes may even take a decade.  相似文献   

6.
洪水灾害遥感监测研究综述   总被引:2,自引:0,他引:2  
赵阳  程先富 《四川环境》2012,(4):106-109
洪水灾害是最严重的自然灾害之一,洪灾造成的损失十分严重,对其进行科学的监测是防灾减灾的基础。在洪水灾害遥感监测研究进展的介绍基础上,着重对中分辨率、高时相、微波、高精度DEM、多源数据遥感洪水监测原理及方法的研究进展进行比较和总结,分析各种数据特点。在此基础上提出了洪水遥感监测向高分辨率、高时相性方向,遥感影像相互订正和利用3S技术是洪涝灾害动态监测发展的方向,为洪水灾害的快速反应和防洪辅助决策提供依据。  相似文献   

7.
Many coastal regions in China are confronted with pressing problems of scarce land resources and heavy population. Over the past 30 years, considerable parts of coastal tidelands have been enclosed and reclaimed for agricultural land uses. To assess, plan, and implement large-scale reclamation programs, up-to-date and reliable information concerning the nature, areal extent, and physical and chemical characteristics of coastal saline lands is essential. This paper reports a remote sensing approach to detecting coastal saline land uses in Shangyu City, China, by using multi-temporal Landsat images. First, with the aid of resolution-sharpened Landsat-7 ETM+ images and their enhanced linear features, a visual interpretation is applied to extract individual dikes. Based on time series images and local government records, a spatial zoning procedure is then used to define six sub-zones with different historical years of reclamation. It shows that a total of 15,668 ha of coastal saline lands were enclosed and reclaimed from 1969 to 1996. Second, a modified land-use classification system for the study area is prescribed, and both unsupervised and supervised classifiers are performed for land-use classifications of grouped sub-zones. Information obtained from the spatial zoning, Tasseled Cap transformation and Normalized Difference Vegetation Index, is also utilized to facilitate the supervised classification process. Finally, a detailed land-use map is produced, with an overall classification accuracy of 77.8%. Results show that dominant agricultural land uses of sub-zones are changed with historical reclamation years, from saline lands with wildgrass (very recently reclaimed) to aqua-farm ponds, to cotton fields, and to paddy fields and orchards (very early reclaimed). This transform process is primarily affected by soil salinities, and according to a soil survey an electrical conductivity of saturation extract decreased from 7.3 ds/m in the saline land reclaimed in 1996 to below 2 ds/m in the land reclaimed before 1969. The study concludes that multi-temporal remotely sensed images are important and effective data sources for monitoring the rapid changes of coastal land uses.  相似文献   

8.
从人地关系理论出发以土地利用变化为切入点通过野外调查和遥感动态监测对干旱区绿洲土地覆盖变化规律进行了研究.在考察数据和对遥感图像的分类结果的评价的基础上对干旱区绿洲土地利用/土地覆盖空间动态变化进行规律性分析提出只有协调人地关系、加强区域地理建设才是使干旱区绿洲地区避免荒漠化的唯一道路.  相似文献   

9.
The increasing demand for fresh water has necessitated the exploration for new sources of groundwater, particularly in hard rock terrain, where groundwater is a vital source of fresh water. A fast, cost effective and economical way of exploration is to study and analyze remote sensing data. Interpreted remote sensing data was used to select sites for carrying out surface geophysical investigations. Various geomorphologic units were demarcated and the lineaments were identified by interpretation of remote sensing satellite images. The potential for occurrence of groundwater in the watershed areas was classified as very good, good, moderate and poor by interpreting the images. Sub-surface geophysical investigations, namely vertical electrical soundings, were carried out to delineate potential water-bearing zones. Integrated studies of interpretation of geomorphologic and geophysical data were used to prepare a groundwater potential map. The studies reveal that the groundwater potential of shallow aquifers is due to geomorphologic features and the potential of deeper aquifers is determined by lineaments such as faults and joints.  相似文献   

10.
Remote sensing has emerged as one of the major techniques for the analysis and delineation of large floods. This analysis can provide data invaluable for the hydrological management of large river systems. A need for information on the extent of floodplain inundation for the lower reaches of the largest river in the UK was met by a search through Landsat images of floods and the analysis of the best example recorded. Automated classification of the Landsat imagery of this flood on the river Severn in 1977 was used to provide estimates of the extent and spatial distribution of inundation. Flood images were generated using the Plessey IDP 3000 image processor, and the maps derived accorded well with aerial photography and qualitative flood information. Three distinct floodplain environments were delineated and flood images produced by different spectral bands compared. Specific questions prompted by flood hazard management and concerning the processes and extent of flooding were answered by the Landsat data analysis. Management of the flood risk of large rivers is expensive and remote sensing data is a relatively cheap and effective way of monitoring control works and providing data for the prediction of the effects of future hydrological works. Remote sensing is a practical way in which spatial information concerning the behavior of large dynamic systems can be obtained both quickly and relatively cheaply.  相似文献   

11.
Remotely sensed variables such as land cover type and snow-cover extent can currently be used directly and effectively in a few specific hydrologic models. Regression models can also be developed using physiographic and snow-cover data to permit estimation of discharge characteristics over extended periods such as a season or year. Most models, however, are not of an appropriate design to readily accept as input the various types of remote sensing parameters that can be obtained now or in the future. Because this new technology has the potential for producing hydrologic data that has significant information content on an areal basis, both inexpensively and repetitively, effort should be devoted now to either modifying existing models or developing new models that can use these data. Minor modifications would at least allow the remote sensing data to be used in an ancillary way to update the model state variables, whereas major structural modifications or new models would permit direct input of the data through remote sensing compatible algorithms. Although current remote sensing inputs to hydrologic models employ only visible and near infrared data, model modification or development should accommodate microwave and thermal infrared data that will be more widely available in the future.  相似文献   

12.
Traditional strategies of resource use in lowland coastal areas may play a very significant role in modern environmental management since, in many ways, the cultural and biological diversity peculiar to these ecoystems that we now wish to protect are the product of human efforts rather than the product of nature alone. We will illustrate this using the example of the so-called closes (enclosures) in the Natural Park of the Aiguamolls de l'Emporda (Catalonia, Spain). Closes are pasture fields surrounded by tree screens that remain inundated part of the year but that can be used for cattle grazing during the rest of the time. Because of agricultural modernization in the 1960s and 1970s many closes were turned into permanent agricultural fields. Since the creation of the Natural Park in 1983, there has been an attempt to recover these traditional land uses although not without some opposition by the farming sector.  相似文献   

13.
The primary role of remote sensing in land management and planning has been to provide information concerning the physical characteristics of the land which influence the management of individual land parcels or the allocation of lands to various uses These physical characteristics have typically been assessed through aerial photography, which is used to develop resource maps and to monitor changing environmental conditions These uses are well developed and currently well integrated into the planning infrastructure at local, state, and federal levels in the United States.Many newly emerging uses of remote sensing involve digital images which are collected, stored, and processed automatically by electromechanical scanning devices and electronic computers Some scanning devices operate from aircraft or spacecraft to scan ground scenes directly; others scan conventional aerial transparencies to yield digital images. Digital imagery offers the potential for computer-based automated map production, a process that can significantly increase the amount and timeliness of information available to land managers and planners.Future uses of remote sensing in land planning and management will involve geographic information systems, which store resource information in a geocoded format. Geographic information systems allow the automated integration of disparate types of resource data through various types of spatial models so that with accompanying sample ground data, information in the form of thematic maps and/ or aerially aggregated statistics can be produced Key issues confronting the development and integration of geographic information systems into planning pathways are restoration and rectification of digital images, automated techniques for combining both quantitative and qualitative types of data in information-extracting procedures, and the compatibility of alternative data storage modes  相似文献   

14.
Monitoring Parks Through Remote Sensing: Studies in Nepal and Honduras   总被引:3,自引:0,他引:3  
The effectiveness of parks as management regimes is hotly contested. Much of the current discussion centered around comparisons of management regimes can be traced to a dearth of cross-site quantitative evaluations. Remote sensing provides a particularly effective tool for this purpose, yet analysis of remotely sensed data requires fieldwork to interpret human activities and the socioeconomic and political contexts that relate to land cover change. This paper examines the effect of establishment of the Celaque National Park, Honduras, and the Royal Chitwan National Park buffer zone, Nepal, on limiting deforestation. In Celaque, the park itself has been largely successful in maintaining forest cover. However, recent changes in land use patterns have led to increasing pressure on the park boundaries, exacerbated by the lack of involvement of local residents. In the Royal Chitwan National Park, in contrast, participatory approaches towards co-management have been implemented over the past decade in the park buffer zone. With significant incomes derived from ecotourism, complete protection of the buffer zone forest has been adopted, leading to significant regrowth of tree cover. However, local decision-making power is limited, and buffer zone management has largely proven successful due to the investment and support provided by international donor agencies. These two case studies demonstrate the utility of remote sensing and Geographical Information Systems analysis in providing a spatiotemporal perspective for assessing management policies. They also demonstrate the importance of fieldwork to provide a nuanced understanding of the socioeconomic and institutional conditions affecting the outcomes of forest management regimes.  相似文献   

15.
徐建辉  许晓静 《资源开发与市场》2010,26(3):195-197,F0002
分析了QuickBird多光谱遥感影像各个波段的光谱特征,并进行了定量评价。根据信息量的大小和波段相关性得到最佳波段组合,在最佳组合波段下利用遥感影像处理软件ERDAS9.2选择或利用建模模块建立不同的影像融合模型对QuikBird多光谱数据与全色遥感影像进行融合,按照定性及定量指标对融合前后的遥感影像进行色彩、分辨率及信息量评价,得到QuikBird影像数据最佳融合方法。  相似文献   

16.
目前,遥感监测能有效解决水环境监测的大范围性、连续性、动态性以及高效性等技术问题。遥感监测越来越受到环保部门的重视。  相似文献   

17.
河北省省级自然保护区以自然生态系统类型为主,人类活动较为频繁,将遥感评估方法应用于河北省省级自然保护区生态环境变化评估具有重要意义。本文通过分析高分辨率遥感卫星影像的特点,结合河北省省级自然保护区的实际情况,优先选取分辨率为2m的民用卫星,提出了遥感调查方法在自然保护区人类活动和开发建设活动中自动监测、生态系统格局变化、生态系统质量变化以及人类活动干扰程度四方面的评估应用。  相似文献   

18.
Tropical deforestation is occurring at an alarming rate, threatening the ecological integrity of protected areas. This makes it vital to regularly assess protected areas to confirm the efficacy of measures that protect that area from clearing. Satellite remote sensing offers a systematic and objective means for detecting and monitoring deforestation. This paper examines a spectral change approach to detect deforestation using pattern decomposition (PD) coefficients from multitemporal Landsat data. Our results show that the PD coefficients for soil and vegetation can be used to detect deforestation using change vector analysis (CVA). CVA analysis demonstrates that deforestation in the Kinabalu area, Sabah, Malaysia has significantly slowed from 1.2% in period 1 (1973 and 1991) to 0.1% in period 2 (1991 and 1996). A comparison of deforestation both inside and outside Kinabalu Park has highlighted the effectiveness of the park in protecting the tropical forest against clearing. However, the park is still facing pressure from the area immediately surrounding the park (the 1km buffer zone) where the deforestation rate has remained unchanged.  相似文献   

19.
This paper aims to assess the suitability of remote sensing for enhancing the management of water body resources and for providing an inexpensive way to gather, on a wide area, weed infestation extent and optical parameter linked to the water body status. Remotely sensed satellite images and ancillary ground true data were used to produce land cover maps, trough classification techniques, and water compounds maps, applying radiative transfer models. The study proposed within the framework of the cooperation between Italian Foreign Affair Ministry (through the University of Rome) and Kenyan Authorities has been carried out on the Kenyan part of the Lake Victoria. This lake is one of the largest freshwater bodies of the world where, over the last few years environmental challenges and human impact have perturbed the ecological balance affecting the biodiversity. The objective of this research study is to define the thematic products, retrievable from satellite images, like weed abundance maps and water compound concentrations. These products, if provided with an appropriate time frequency, are useful to identify the preconditions for the occurrence of hazard events like abnormal macrophyte proliferation and to develop an up-to-date decision support system devoted to an apprised territory, environment and resource management.  相似文献   

20.
One central issue affecting the health of native fish species in the Pacific Northwest is water temperature. In situ observation methods monitor point temperatures, while thermal infrared (TIR) remote sensing captures spatial variations. Satellite‐based TIR sensors have the ability to view large regions in an instant. Four Pacific Northwest river reaches were selected to test the ability of both satellite‐based and moderate resolution aircraft‐based TIR remote sensing products to measure river temperatures. Images with resolutions of 5, 15, and 90 meters were compared with instream temperature observations to assess how along stream radiant temperatures are affected by resolution, reach width, and sensor platform. Where the stream reach can be resolved by the sensor, all sensors obtain water temperatures within ±2°C of instream observations. Along stream temperature variations of up to ±5°C were also observed. Trends were similar between two sets of TIR images taken several hours apart, indicating that the sensors are observing actual temperature patterns from the river surface. If sensor resolution is sufficient to obtain fully resolved water pixels in the river reach, accurate temperatures and spatial patterns can be observed. The current generation of satellite‐based TIR sensors is, however, only able to resolve about 6 percent of all Washington reaches listed as thermally impaired.  相似文献   

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