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1.
海岸人工地貌建设是沿海国家开发利用海岸带资源的重要方式,海岸人工岸线的形成改变了自然岸线的格局,并影响着岸线的自然演替规律。基于1990,2000和2010年3期TM遥感影像,提取不同时相的浙江省大陆海岸线信息,对浙江大陆海岸线类型构成及人工岸线建设对岸线格局的影响进行了分析。结果表明:(1)受人类开发活动的影响,近20 a来浙江大陆海岸格局以人工岸线不断增长为特征;(2)不同岸段的人工岸线增长速度有明显差异,以杭州湾、三门湾及台州湾沿岸岸线变化最为显著;(3)20 a间,浙江大陆岸线整体向海推进趋势明显,仅少数岸线发生了海岸蚀退;(4)人工岸线的建设通过对自然岸线的截弯取直,缩短了自然岸线的长度,降低了自然岸线的曲折度,却使浙江省大陆海岸线的多样性指数不断增加。  相似文献   

2.
渤海湾内海岸的连续开发导致岸线 、海床发生较大变化, 同时影响着湾内的水沙通量。根据不同时期的遥感影像、 实测地形和水文泥沙资料, 统计分析了渤海湾岸线 、面积和海床冲淤变化, 构建了渤海潮流泥沙数学模型, 模拟了 1984 年、 2006 年和 2015 年三个时期的水沙分布, 探究了海岸连续开发对水沙分布和通量引起的累积效应。结果表明: 渤海湾岸线和 海湾面积变化主要发生于 2005 年后, 与 1984 年相比, 2020 年的岸线长度增长超过 185%,海湾面积减少近 19%;曹妃甸港 区南侧海域冲刷基本在 2 m 等深线以内, 而近岸和港池水域基本呈现淤积状态, 淤积幅度在 2 m 以内; 海湾的连续开发利用 使得湾内分潮波振幅增大 、传播速度减缓, 近岸海域的余流变化较为明显,南部较北部海域更甚;西北湾顶 0.2 kg/m3 悬沙 分布区域不断缩小, 西南近岸 0. 15 kg/m3 悬沙分布区域向中部海域推进; 悬沙通量变化与潮流通量并不完全一致, 呈外海增 加、近岸整体降低的变化特征, 湾内向外海输移泥沙的能力减弱。  相似文献   

3.
海岸线对沿海地区生态环境、潮间带的滩涂资源量以及湿地生态系统等都具有重要的影响。基于遥感与GIS技术,提取并矢量化了山东省威海地区1988、1994、1999、2007、2014年和2017年6个时期的海岸线,对其30 a来的时空变化及其驱动力进行了研究。结果表明:威海市海岸线的变化主要体现在不同岸线类型长度所占比例的改变;在总长度上,威海市海岸线呈现出持续增长的趋势,30 a间增加了74. 7 km,增长速率为2. 49 km/a;在岸线类型方面,该地区以人工岸线为主,其中养殖围堤的比重最大,占岸线总长度的39. 4%。研究认为,威海市海岸线的变化主要受人为因素的影响,这些因素会引起海岸带多种资源和生态过程的改变,会直接影响沿海人们的生存和发展。  相似文献   

4.
It has recently been realized that the Arctic undergoes drastic changes, probably resulting from global change induced processes. This acts on the cycling of matter and on biogenic elements in the Arctic Ocean having feedback mechanisms with the global climate, for example by interacting with atmospheric trace gas concentration. A contemporary budget for biogenic elements as well as suspended matter for the Arctic Ocean as a baseline for comparison with effects of further global change is, thus, needed. Available budgets are based on the late Holocene sedimentary record and are therefore quiet different from the present which has already been affected by the intense anthropogenic activity of the last centuries.

We calculated a contemporary suspended matter and organic carbon budget for the Kara Sea utilizing the numerous available data from the recent literature as well as our own data from Russian-German SIRRO (Siberian River Run-off) expeditions. For calculation of the budgets we used a multi-box model to simplify the Kara Sea shelf and estuary system: input was assumed to comprise riverine and eolian input as well as coastal erosion, output was assumed to consist of sedimentation and export to the Arctic Ocean. Exchange with the adjacent seas was considered in our budget, and primary production as well as recycling of organic material was taken into account. According to our calculations, about 18.5 × 106 t yr− 1 of sediments and 0.37 × 106 t yr− 1 of organic carbon are buried in the estuaries, whereas 20.9 × 106 t yr− 1 sediment and 0.31 × 106 t yr− 1 organic carbon are buried on the shelf. Most sources and sinks of our organic carbon budget of the Kara Sea are in the same order of magnitude, making it a region very sensitive to further changes.  相似文献   


5.
基于遥感的黄河三角洲海岸线变化研究   总被引:3,自引:0,他引:3  
以黄河三角洲的Landsat TM/ETM+影像(1989~2009年)为数据源,采用遥感与地理信息系统技术,对黄河三角洲的岸线与面积变化进行监测。结果表明:1989年以来,黄河三角洲的岸线形状及长度均发生了较大变化,其中北部的刁口河流路区岸线向内陆蚀退明显;清水沟流路区的岸线整体向海域推进,部分区域有蚀退现象;神仙沟流路区主要为人工海堤,岸线变化不大。黄河三角洲的整体面积在1989~2009年处于增加中,但2006~2009年,面积变化为负值。从淤蚀情况来看,1989~2009年,黄河三角洲的淤蚀强度经历了"和缓-剧烈"的过程。这说明20年来黄河三角洲整体上处于增长发育中,但2006年后三角洲整体上呈现蚀退现象,同时黄河三角洲的淤蚀情况变得比以往更剧烈,意味着更强的海陆交汇作用和岸线变化。黄河的入海流路、水沙量、降水量等是影响三角洲岸线变化的重要因素,而人工堤坝能够在一定程度上维持海岸线的稳定。对黄河三角洲海岸线变化的研究有助于有效地管理和保护区域的社会和生态环境。  相似文献   

6.
布容法则及其在中国海岸上的应用   总被引:12,自引:1,他引:11  
布容(Bruun)法则是预测海平面上升引起海岸侵蚀最早的方法也是最简单的方法。根据中国砂质和淤泥质海岸的情况,布容法则可定性地解释海平面上升与海岸侵蚀的关系,在满足它要求条件的海岸地段和发育时期,用它预测海岸侵蚀或许是可能的。但是,若不严格审查海岸环境和条件,把它作为海平面上升情况预测海岸侵蚀的普遍模式,有待更多的研究加以证明。  相似文献   

7.
珊瑚礁海岸海滩和礁坪是海岸作用是活跃的部分,也是近几十年来与海岸发育,海岸侵蚀联系最密切的部分,这一部分高潮时被淹没,低潮时完全出露或大部分出露,使得在此进行地质填图成为可能,这样的地质图可以提供许多信息,如沉积物粒度分布规律,沉积物来源和搬运方向,海滩岩所指示的古海岸线位置,人类活动特别是海岸工程对沉积物分布的影响以及海岸线的变化过程和趋势,在礁坪上开挖的人工水道内测流,能够了解水流的性质以及是否有足够的速度搬运沉积物,从而了解人工水道对海岸的影响和预测海岸的状态,这些方法也可以用于大陆泥质和砂质第岸侵蚀的研究。  相似文献   

8.
A model is described that was designed to predict the shoreline changes due to the most widely distributed types of coastal structures such as groins, jetties, breakwaters, and access channels, which disturb the alongshore sediment fluxes. The key assumptions based on empirical data are related to the extension of the areas with the sediment excess and deficit. It is shown that the most important factors are, on the one hand, the size of the structure and the depth of its location and, on the other hand, the width of the alongshore sediment flux and the depth at its outer edge. The relations between these parameters determine the spatial scales of the morphology perturbations at a given coast. The temporal scale of the shoreline changes considered is restricted to the period a few years after the structure was built. The input data and the typical output results are illustrated by an example of calculations.  相似文献   

9.
泰国湾近30年海岸线变迁剧烈。文章基于1988年、1996年、2006年和 2016年4个时期Landsat TM/OLI中等分辨率卫星遥感影像数据,开展了近30年泰国湾岸线长度时空变迁遥感监测,并应用数字海岸分析系统(DSAS)计算出4期岸线变迁速率,给出了4个时期泰国湾侵蚀淤积面积状况,分析了岸线变迁的自然因素和人类活动因素。并从岸线增长速率、岸线变迁速率、蚀淤面积状况、岸线类型变化4个方面给出结论。  相似文献   

10.
According to the fractal theory,the spatial fractal character of coastline is preliminarily dis-cussed on the basis of GIS in this paper.Two aspects are considered:one is the length demarcation ofcoastline with different scales,and the other is the confirmation of existence of the fractal character on dif-ferent boundaries of tidal flats.Finally,some significant conclusions are drawn:(1)The coastline ofJiangsu Province has the fractal character and its dimension is 1.0696.(2)It conforms to the exponentialcorrelation between different lengths(L)of coastline and scales(k).It conforms to the formula lgL(k)=-1.029lgk+2.9544 in the continental coastline of Jiangsu province.(3)Different boundaries of a tidal flathave fractal characters,and different fractal dimensions indicate different comparative intensities of ero-sion and deposition on the tidal flat.(4)The reciprocity between land and sea may affect the value offractal dimension of a coastline,just as the lithology,substantial constituent and geological s  相似文献   

11.
《Ocean & Coastal Management》2006,49(7-8):462-475
A mangrove ecosystem shows close links between geomorphology and vegetation assemblage. In addition, the vegetation can change over time as landforms can accrete or erode, which is a direct response to coastal sedimentary processes. This demonstrates that significant changes can occur on short time scales and mangroves provide an excellent register of these modifications. Therefore, mangrove morphology and sedimentation are good indicators of interactions between relative sea level changes, coastal processes and sediment supply. These interactions are responsible for landward migration of the shoreline (erosion) and seaward migration of the shoreline (accretion), which is possible to detect from multi-date satellite data and field observations. Mangroves are one of the best geo-indicators in global coastal change research and they are an excellent procedure to detect and quantify coastal modifications.  相似文献   

12.
赖志坤 《海洋科学》2012,36(8):75-78
应用海岸线变化定量分析原理,综合分析了近50年来泉州湾海岸线变化的基本特征,计算了古浮澳岸段的海岸线变化速率.研究分析结果表明,泉州湾海岸线长度以0.94km/a的速率减小,海域面积(含岛屿)以1.01 km2/a的速率减小;古浮澳岸段呈现南北淤进,中间侵淤交互的岸线变化趋势.通过了解泉州湾海岸线变化特征和变化趋势,获取海岸线变化速率数据,为泉州湾海域的可持续开发与管理提供参考依据.  相似文献   

13.
填海造陆对海岸环境的影响主要体现在改变海岸线长度与形态及直接吹填沙导致近海海底地形地貌变化~([1]),这些变化影响着海岸带规划管理和可持续发展,具有重要的理论和现实意义。文章利用滨海新区遥感影像及其海图资料,对该区域近30年海岸线变迁、围填海演变及海底地形信息进行了提取,并对其具体进程和驱动因素进行了研究。研究表明:30年间,滨海新区海岸线变迁是向海洋推进,且推进的趋势越来越明显,岸线长度增长趋势愈发明显,变迁面积较大。针对填海造陆引起围堤基底冲刷问题,笔者建议对中度冲刷区采取防护工程措施、岸外消浪工程和加强动态监测等措施防止泥沙向航道下移。  相似文献   

14.
海岸侵蚀对海岛紧缺的陆地资源及旅游价值较大的沙滩危害巨大。基于卫星遥感、有人航空摄影、无人机航测、GPS和现场调查等多源数据,利用GIS分析了东山岛海岸线类型、位置与长度变化及滩面冲蚀演变。研究表明,东山岛多处曲折自然岸线转化为较为平直的人工岸线致使整体岸线长度减少,无人机高程反演满足滩面排水冲蚀监测精度要求,乌礁湾和山南湾不同养殖排水方式形成不同特征的滩面冲沟,改变了沙滩微地貌形态。海平面上升和台风风暴潮是长期趋势性和短期突发性侵蚀因素的代表,当前短时间尺度的人类活动已成为滩面冲蚀的最主要因素,且有可能转变为长期趋势性因素。  相似文献   

15.
In a closely integrated system, (sub-) littoral sandy sediments, sandy beaches, and sand dunes offer natural coastal protection for a host of environmentally and economically important areas and activities inland. Flooding and coastal erosion pose a serious threat to these environments, a situation likely to be exacerbated by factors associated with climate change. Despite their importance, these sandy ‘soft’ defences have been lost from many European coasts through the proliferation of coastal development and associated hard-engineering and face further losses due to sea-level rise, subsidence, storm surge events, and coastal squeeze. As part of the EU-funded THESEUS project we investigated the critical drivers that determine the persistence and maintenance of sandy coastal habitats around Europe's coastline, taking particular interest in their close link with the biological communities that inhabit them. The successful management of sandy beaches to restore and sustain sand budgets (e.g. via nourishment), depends on the kind of mitigation undertaken, local beach characteristics, and on the source of ‘borrowed’ sediment. We found that inter-tidal invertebrates were good indicators of changes linked to different mitigation options. For sand dunes, field observations and manipulative experiments investigated different approaches to create new dune systems, in addition to measures employed to improve dune stabilisation. THESEUS provides a ‘toolbox’ of management strategies to aid the management, restoration, and creation of sandy habitats along our coastlines, but we note that future management must consider the connectivity of sub-littoral and supra-littoral sandy habitats in order to use this natural shoreline defence more effectively.  相似文献   

16.
为加强对江苏省海岸带的保护和开发利用,文章基于卫星遥感影像,通过提取瞬时水边线和推算潮位特征线,分析1984—2016年江苏省海岸线和沿海滩涂的变迁。研究结果表明:江苏省自然岸线逐渐减少,人工岸线大幅增加,海岸线明显向海推进;淤长岸段主要分布在辐射沙洲北翼的射阳河口至川东港南,冲刷岸段主要分布在废黄河三角洲的灌河口北至中山河口南和扁担河口北至双洋河口南,全省海岸淤长长度和平均淤长速率均大幅下降;沿海各地的潮间带平均宽度均有不同程度的缩短,滩涂围垦强度大是重要影响因素。  相似文献   

17.
1973—2018年珠江三角洲海岸线时空演变分析   总被引:1,自引:0,他引:1       下载免费PDF全文
通过遥感和GIS技术获取1973—2018年的Landsat TM/OLI遥感影像为数据源,结合地理背景资料,分析45 a来珠江三角洲地区海岸线时空演变情况。结果表明:珠江三角洲地区海岸线变迁显著,大量的淤泥质岸线转变为城镇工业岸线和港口岸线,珠江三角洲地区岸线人工化指数不断上升,岸线类型朝向多元化方向发展,岸线总长度和分形维数不断增加,港口建设、滨海工业区、围垦填海等是岸线长度和分形维数增加的主要因素;海岸线演变呈现明显的区域特征,变化较大区域主要集中在深圳大鹏湾、广州南沙和珠海斗门;从岸线开发利用主体结构上看,各大岸区都出现了不同类型的变化趋势,城镇工业岸线与港口岸线取代自然岸线成为各区海岸线的主体类型;各地区开发利用强度不断上升,其中深圳市开发强度增速最快,社会活动和区位政策是引起岸线演变的主要驱动因素。  相似文献   

18.
利用遥感影像和GIS技术相结合获取福建省1995、2001、2010、2017年共4期海岸线的时空分布情况,并结合网格法计算各时期海岸线的分形维数,结合获取数据分析海岸线的时空变化特征、海岸线长度变化与分形维数变化之间的关系以及影响海岸线变化的原因。结果表明:1995—2017年福建省海岸线长度呈持续增加趋势,共增加388.99 km。从时间方面来看,2010年之后海岸线长度进入快速增长时期,其中2010—2017年是海岸线长度变化最显著的时期;从区域上来看,以宁德和莆田岸线变化最强烈,其他地市相对较稳定。1995—2017年研究区海岸线分形维数总体呈现先增加后减小趋势,其中宁德、福州、泉州分形维数变化比其他地市要复杂。研究区历史海岸线长度变化与分形维数变化之间存在着一定的相关关系,对各地市海岸线长度变化与分形维数变化统计分析表明,总体来看局部海岸线长度的增加或减小会导致整体海岸线分形维数增大或减小,且呈正比例变化。对1995—2017年研究区各时段海岸线变化对应的面积汇总情况来看,人类活动是影响研究区海岸线变化的主要原因,与人类活动相比,自然变化如河口淤积与侵蚀等对海岸线影响较小。  相似文献   

19.
The main objective of the Conscience project was to develop and test concepts, guidelines and tools for the sustainable management of erosion along the European coastline, based on the best available scientific knowledge and on existing practical experience. Four concepts are potentially capable of providing the nexus between scientific knowledge and management: coastal resilience, coastal sediment cell, favourable sediment status and strategic sediment reservoir. The project has tested the use of these concepts and found that they are useful, provided that they are positioned and linked within a logical structure that we shall call the Conscience “Frame of Reference”, defined in time and space and supported through data and monitoring. Practical experience in six coastal sites in Europe has shown that the use of this Frame of Reference together with these concepts can make management objectives explicit and transparent. It can therefore support the design of an appropriate, resilience based coastal erosion management practice.  相似文献   

20.
基于1987—2015年Landsat遥感影像,运用ENVI与MapInfo软件提取岸线,分析红河三角洲近30年岸线演变规律,并结合历史岸线、红河多年径流量与输沙量,以及过境该海域多年热带气旋数量等数据,初步探讨红河三角洲岸线演变的影响因素。研究表明红河三角洲岸线在时间上呈前进与后退交替变化特征,其中巴拉特河口以南的岸段以后退为主,河口北部岸段总体以前进为主。巴拉特河口地区淤进与蚀退变化频繁,主要与上游建坝导致入海沙量变化以及台风造成的侵蚀有关。  相似文献   

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