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海岸生物地貌过程研究海岸带生物过程和动力-沉积-地貌过程之间的双向相互作用,是海岸生态系统响应和反馈全球变化的重要机制,被列为全球变化核心项目海岸带陆海相互作用研究的重点内容。20世纪90年代以来的调查研究揭示了华南红树林和珊瑚礁热带生物海岸生物地貌过程的主要特点。造礁石珊瑚的高生长率和珊瑚礁高堆积速率是珊瑚礁生物地貌过程的物质基础;红树林生态系统的高生产力、高归还率和捕沙促淤功能是红树林生物地貌过程的物质基础。热带生物海岸地貌结构显示分带性和生物地貌类型和动力地貌类型的叠加和共存,潮汐水位严格控制群落分布格局并形成重要的生物地貌界限。热带生物海岸生物地貌过程有利于消除或减缓海平面上升的浸淹效应。热带生物海岸不断加剧的人类活动干扰和生态破坏导致生物地貌功能削弱和海岸资源环境恶化。 相似文献
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海岸带是陆地、海洋和大气相互作用最强烈的地带,也是受全球气候、海平面变化以及人类活动影响最大的地区。海岸带动力过程具有明显的海洋-陆架-海湾-海岸多尺度多物理场特点,动力地貌过程和响应机制极具特色。台风等极端气象事件的频繁发生,工程措施等强人类活动的影响,导致海岸带动力地貌演变规律呈现出更大的不确定性。从高强度扰动下海岸动力条件、极端条件影响下海岸动力地貌特征和强人类活动影响下海岸动力地貌特征等方面,综述了已有研究工作进展。全球气候变化和人类活动共同作用的海岸带多尺度动力过程和海岸地貌响应内在机制极其复杂,在未来海岸动力地貌特征的研究中,需要进一步从大气、海浪、海洋和泥沙等多物理场,海洋、陆架、海湾和海岸等多尺度,动力条件、泥沙输移和地貌塑造等多过程的角度,探究高强度扰动下海岸带动力过程、响应机制和演变规律。 相似文献
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宁德地质公园奇特景观的科学价值浅析 总被引：1，自引：1，他引：0
宁德地质公园集晶洞花岗岩地貌、火山岩地貌、河床侵蚀地貌、海岸海蚀地貌于一体,景观具有很高的观赏价值。公园的许多地质遗迹具有稀有性和独特性,多种地貌景观的组合,反映了其地质历史的复杂性。地质遗迹与生物、人文景观的结合使宁德地质公园具有丰富的科学内涵和科普价值。 相似文献
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宁德地质公园集晶洞花岗岩地貌、火山岩地貌、河床侵蚀地貌、海岸海蚀地貌于一体,景观具有很高的观赏价值.公园的许多地质遗迹具有稀有性和独特性,多种地貌景观的组合,反映了其地质历史的复杂性.地质遗迹与生物、人文景观的结合使宁德地质公园具有丰富的科学内涵和科普价值. 相似文献
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西藏地区经历了复杂的地质作用，造就了其地形的独特性，从而形成了独有的地貌特征，自然资源中具有旅游开发价值的为数不少。在旅游业兴盛繁荣的今天，挖掘并开放西藏的旅游资源已显得相当重要。本文在介绍西藏旅游资源概况的基础上，讨论了开发西藏自治区旅游资源的意义和作用。 相似文献
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John Rivers Max Engel Robert Dalrymple Ruqaiya Yousif Christian J. Strohmenger Ismail Al-Shaikh 《Sedimentology》2020,67(1):534-558
Barrier islands are important landforms in many coastal systems around the globe. Studies of modern barrier island systems are mostly limited to those of siliciclastic realms, where the islands are recognized as mobile features that form on transgressive coastlines and migrate landward as sea-level rises. Barrier islands of the ‘Great Pearl Bank’ along the United Arab Emirates coast are the best-known carbonate examples. These Holocene islands, however, are interpreted to be anchored by older deposits and immobile. The mid-Holocene to late-Holocene depositional system at Al Ruwais, northern Qatar, provides an example of a mobile carbonate barrier island system, perhaps more similar to siliciclastic equivalents. Sedimentological and petrographic analyses, as well as 14C-dating of shells and biogenic remains from vibracored sediments and surface deposits, show that after 7000 years ago a barrier system with a narrow back-barrier lagoon formed along what is now an exposed coastal zone, while, contemporaneously, a laterally-extensive coral reef was forming immediately offshore. After 1400 years ago the barrier system was forced to step ca 3 km seaward in response to a sea-level fall of less than 2 m, where it re-established itself directly on the mid-Holocene reef. Since that time, the barrier has retreated landward as much as 1000 m to its current position, exposing previously-deposited back-barrier lagoonal sediment at the open-coast shoreline. In modern neritic warm-water carbonate settings mobile barrier island systems are rare. Their construction and migration may be inhibited by reef formation, early cementation, and the relative inefficiency of sourcing beach sediments from open carbonate shelves. Carbonate barrier island systems likely formed more commonly during geological periods when ramps and unrimmed shelves predominated and in calcite seas, when meteoric cementation was minimized as a result of initial calcitic allochem mineralogy. As with their siliciclastic analogues, however, recognition of the influence of these transient landforms in the rock record is challenging. 相似文献
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The coastal wind-eroded landform, one of the kinds of wind-eroded landforms which widely distribute and have complex causes of formation, now is being much more concerned in recent years with the major research development of wind-eroded landform based on the advanced research techniques and methods. According to the summarization about the main progresses of foreign research on coastal wind-eroded landform in different periods, the status and dispute of research on coastal wind-eroded landform in China, and the development difference of coastal and mainland wind-eroded landform in China, it is essential work to improve the research on the coastal wind-eroded landform in China. Finally future research directions of coastal wind-eroded landforms are suggested such as to find out the types and their distribution features of coastal wind-eroded landforms in China, investigate their morphology and change characteristics,probe into the interaction essence between the morphological changes and the airflow and wind-sand flux of typical coastal wind-eroded landforms, and explore the model and laws of formation and evolution of coastal wind-eroded landforms in China. 相似文献
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R. Morton 《Environmental Geology》2002,42(7):711-724
The primary geoindicators appropriate for monitoring environmental changes in the humid tropics are transitory surface water levels, shoreline position, wetlands distribution, coral reefs, landforms, and sediment sequence and composition. Lateral zonations and temporal successions of vegetation also can be used as geoindicators of riverine and shoreline changes. All of these coastal geoindicators are sensitive to regional tectonic processes and anthropogenic alterations and they typically reflect significant changes in coastal conditions such as fluvial processes, coastal energy, water quality, relative sea level, and sediment supply. Where humid tropical coasts coincide with active tectonic margins, indicators of seismic activity are critical to understanding coastal changes associated with co-seismic subsidence or uplift, tsunamis, and liquefaction of coastal sediments. Coastal landforms and sedimentary deposits that record late Quaternary environmental changes include perched fluvial and marine terraces, delta-plain morphologies, crevasse-splay deposits, peats and other paleosols, beach ridges, mud capes, and mud volcanoes. Although these features and deposits typically reflect environmental changes spanning more than 100 years, they are relevant to modern processes, management of coastal lands and resources, and prediction of future conditions. In some regions of the humid tropics, large coastal areas are unaffected by hurricanes or typhoons. Nevertheless, these tropical coasts are vulnerable to other non-storm processes, such as El Niño events, tsunamis, and monsoons that increase water levels, and cause widespread flooding and beach erosion. The environmental and political significance of coastal geoindicators increases when they are integrated and applied to issues of human safety and health such as hazards mapping, risk assessment, and dispersion of contaminated sediments. However, to be relevant, those socio-environmental applications demand accurate predictions of future trends and rates of change. 相似文献
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《Proceedings of the Geologists' Association. Geologists' Association》2019,130(3-4):463-472
This paper reviews recent studies of the seabed offshore from the Jurassic Coast and discusses their significance for understanding landforms of the World Heritage Site’s Setting as well as adding to understanding of the structures exposed in the cliffs. The processes of coastal formation as sea-levels rose and fell during the Pleistocene and in the recent post-glacial period are critical for this as they reveal the landforms which preserve former shorelines. Detailed surveys of the seabed provide evidence of the low slope of much of this seabed and so enhance the potential to interpret older terrestrial landforms which have been attributed to uplift of former sea beds. Considering both the seabed and the coast from the Pleistocene to the Anthropocene means that it is possible to assess the human impact on these landforms and processes, as well as the natural timescale within which changes occur. The paper describes the seabed geomorphology, relating this, where appropriate, to both the coastal landforms and the exposed structures. Current interpretations of the seabed features and their implications for our understanding of the recent evolution of the Site and Setting are explored. The features of the coast and adjacent sea bed at different phases of the changing coastal environment are discussed to the extent that the available evidence makes this possible, but for much of the area this remains speculative. 相似文献
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海南岛火山海岸以沿小火山口形成的海蚀地貌和全新世火山爆发使局部海湾抬升为海岸阶地、河口堵流并形成深切海湾以及促进了珊瑚礁发育为特征。火山活动改变了海岸带的地势、坡度、动力条件、沉积特征以及海岸演变趋势,火山海岸发育受到构造内动力、波浪、潮流、风化作用等外动力以及生物作用的多重影响。火山岩岩性和时代反映出北部湾湾底的现代拉张构造活动。夏威夷火山海岸的环境效应以造陆和板块移动形成岛链、近期熔岩流喷溢改变地貌和大气质量等为特征。现代日本鹿儿岛火山碎屑喷发物掩埋道路和建筑物并促发泥石流灾害,改变着火山海岸作用过程。对比研究火山海岸及其环境效应,及时预报并进而制定有效的防灾、减灾对策。 相似文献
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论灾害地貌学的性质及研究内容 总被引：1，自引：0，他引：1
灾害地貌学是一门崭新的、正在开拓之中的边缘科学。在前人大量研究的基础上,对灾害地貌的分类和灾害地貌的学科性质及其研究的主要内容进行了探讨。 相似文献
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岩溶地貌在全球广泛分布,造就了丰富多彩的地貌形态及自然景观。在我国湘黔鄂渝交界区存在着极具观赏性的特殊岩溶地貌,其形态特征有别于常见的岩溶地貌。但当前对这套特殊岩溶地貌的名称及其地学价值尚未深入探讨。该类型地貌具有四个基本特点:红颜色、层状凹凸形态、泥质灰岩的成景岩性、土下环境差异溶蚀成因。在对比分析它与红色系地貌、已认识的岩溶形态、常见岩溶地貌的差异性基础上,文章采用“外观特征”+“地貌类型”的命名原则将它命名为“红色层状凹凸岩溶地貌”,简称“红色岩溶”,并提出其科学定义及界定标准。红色岩溶具有重要的地学价值,其极具观赏性的独一无二形态使得红色岩溶具有重要的旅游经济价值。 相似文献
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Takahito Mikami Tomoya Shibayama Miguel Esteban Koichiro Ohira Jun Sasaki Takayuki Suzuki Hendra Achiari Teguh Widodo 《Natural Hazards》2014,71(1):851-870
On October 25, 2010, a large earthquake occurred off the coast of the Mentawai islands in Indonesia, generating a tsunami that caused damage to the coastal area of North Pagai, South Pagai, and Sipora islands. Field surveys were conducted soon after the event by several international survey teams, including the authors’. These surveys clarified the tsunami height distribution, the damage that took place, and residents’ awareness of tsunamis in the affected islands. Heights of over 5 m were recorded on the coastal area of the Indian Ocean side of North and South Pagai islands and the south part of Sipora island. In some villages, it was difficult to evacuate immediately after the earthquake because of the lack of routes to higher ground or the presence of rivers. Residents in some villages had taken part in tsunami drills or education; however, not all villages shared awareness of tsunami threats. In the present paper, based on the results of these field surveys, the vulnerability of these islands with regards to future tsunami threats was analyzed. Three important aspects of this tsunami disaster, namely the geographic disadvantage of the islands, the resilience of buildings and other infrastructure, and people’s awareness of tsunamis, are discussed in detail, and corresponding tsunami mitigation strategies are explained. 相似文献