共查询到20条相似文献，搜索用时 63 毫秒
1.
Ji Zixiu 《中国地理科学(英文版)》1994,(4)
（季子修）（蒋自巽）ＩＭＰＡＣＴＳＯＦＳＥＡＬＥＶＥＬＲＩＳＥＯＮＣＯＡＳＴＡＬＥＲＯＳＩＯＮＩＮＴＨＥＣＨＡＮＧＪＩＡＮＧＲＩＶＥＲＤＥＬＴＡＡＮＤＮＯＲＴＨＪＩＡＮＧＳＵＣＯＡＳＴＡＬＰＬＡＩＮＯ￥ＪｉＺｉｘｉｕ（ＮａｎｊｉｎｇＩｎｓｔｉｔｕｔｅ... 相似文献
2.
At present, approximately 36% of coasts are experiencing net erosion in the Changjiang River delta and the north Jiangsu coastal
plain. Future sea level rise will accelerate the process of coastal erosion. According to the ratio of the calculated value
of coast retreat by Bruun rule to the estimated value by using measured data, the proportion affected by sea level rise in
total coastal erosion has been estimated in this paper. When sea level rises by 20cm, the proportion determined by sea level
rise will increase from 1.0% at present to 2.2% in the future in the coasts of abandoned Huanghe River delta and from 8.5%–9.6%
to 13.5%–15.2% in the north and south banks of the Changjiang River delta. This result is lower than that from the similar
research in the world, and this phenomenon is related with the special development process of the coasts in this area. The
mechanism of accelerating coastal erosion by sea level rise is that sea level is will increase the intensity of tidal current,
wave and storm surge and decrease the ability to reduce the force of waves on the tidal flat and coastal wetland due to the
loss of their areas. Therefore, the length of erosion coasts will increase, the sedimentation rate of accretion coasts will
decrease or even turn accretion into erosion, the width of tidal flat will reduce and coastal slope will increase. So the
project of coastal protection of this area must be reinforced.
Project funded by the National Natural Science Foundation of China and the Chinese Academy of Sciences. 相似文献
3.
Coastal Erosion Along the West Coast of the Taiwan Strait and It’s Influencing Factors 总被引：1，自引：0，他引：1
Based on the field surveys and repeated cross-profile observations combined with the comparison of many years’ topog-raphic maps,this study shows the spatial variability and varying patterns of coastal erosion along the west coast of the Taiwan Strait.Regional differentiation in the Meso-Cenozoic coastal tectonics determined the irregular coastline and geological background for large-scale coastal erosion distribution.The intensity of coastal erosion on the west side of the Taiwan Strait is mild in the nort... 相似文献
4.
《中国海洋大学学报(英文版)》2015,(5)
The beach studied in this paper spans a length of 51 km and is one of several long sandy beaches in the southern Bohai Strait. Due to the obstruction of islands in the northeast and the influence of the underwater topography, the wave environment in the offshore area is complex; beach types and sediment transport characteristics vary along different coasts. The coastlines extracted from six aerial photographs in different years were compared to demonstrate the evolving features. Seven typical beach profiles were selected to study the lateral beach variation characteristics. Continuous wind and wave observation data from Beihuangcheng ocean station during 2009 were employed for the hindcast of the local wave environment using a regional spectral wave model. Then the results of the wave hindcast were incorporated into the LITDRIFT model to compute the sediment transport rates and directions along the coasts and analyze the longshore sand movement. The results show that the coastline evolution of sand beaches in the southern Bohai Strait has spatial and temporal variations and the coast can be divided into four typical regions. Region(I), the north coast of Qimudao, is a slightly eroded and dissipative beach with a large sediment transport rate; Region(II), the southwest coast of Gangluan Port, is a slightly deposited and dissipative beach with moderate sediment transport rate; Region(III), in the central area, is a beach that is gradually transformed from a slightly eroded dissipative beach to a moderately or slightly strong eroded bar-trough beach from west to east with a relatively moderate sediment transport rate. Region(IV), on the east coast, is a strongly eroded and reflective beach with a weak sediment transport rate. The wave conditions exhibit an increasing trend from west to east in the offshore area. The distribution of the wave-induced current inside the wave breaking region and the littoral sediment transport in the nearshore region exhibit a gradual weakening tendency from west to east, which is opposite to the trend of the wave conditions outside the breaking region. The presence of submerged shoal(Dengzhou Shoal), deep trough(Dengzhou Channel), islands and irregular topography influnces the wave climate, beach types, wave-induced current features, littoral sediment transport trends and coastline evolution patterns in the southern Bohai Strait. Human activities, such as the sand exploitation of Dengzhou Shoal and other coastal engineering projects, also influence the beach morphology and coastline evolution. 相似文献
5.
XUEChunting RussellHoworth HEChaoxiong 《中国海洋大学学报(英文版)》2004,3(1):99-105
1 Introduction Oceanicislandsfallintoseveraldifferenttypes .Thecommontypesarevolcanicislands ,atollsandemer gentlimestoneislands (ScottandRotondo ,1 983;Woodroffe ,1 992 ) .Avolcanicislandinthetropicshasfringingor andbarrierreefs .Anatollhasaring shaped… 相似文献
6.
Guishan Yang 《中国地理科学(英文版)》1995,5(2):104-115
Due to global climate warming and natural and man-made land subsidence etc., relative sea level rise in the coastal plains
of China will exceed 2–3 times over the golbal mean value during the first half part of the 21st century. It will result in
a series of adverse impacts on evolution of natural environment and socioeconomic development of the coastal area. This paper
analyses environmental and resource effects induced by relative sea level rise in China’s coastal areas on the basis of rough
estimate of future relative sea level rise. These effects include inundating tidal flat and wetlands and increase in inundated
risk of coastal habitable land, exacerbating storm surge. coastal erosion, flooding and salt water intrusion hazards, as well
as endangering land, water, tourism and living resources and their utilization. 相似文献
7.
RELATIVE SEA LEVEL RISE AND ITS EFFECTS ON ENVIRONMENT AND RESOURCES IN CHINAS COASTAL AREAS 总被引：2，自引：0，他引：2
杨桂山 《中国地理科学(英文版)》1995,(2)
ＲＥＬＡＴＩＶＥＳＥＡＬＥＶＥＬＲＩＳＥＡＮＤＩＴＳＥＦＦＥＣＴＳＯＮＥＮＶＩＲＯＮＭＥＮＴＡＮＤＲＥＳＯＵＲＣＥＳＩＮＣＨＩＮＡＳＣＯＡＳＴＡＬＡＲＥＡＳ￥ＹａｎｇＧｕｉｓｈａｎ（杨桂山）（ＮａｎｊｉｎｇＩｎｓｔｉｔｕｔｅｏｆＧｅｏｇｒａｐｈｙａｎ... 相似文献
8.
丁字湾地区是山东半岛蓝色经济区划9大核心区之一,是胶东经济圈一体化建设的焦点,发展远景广阔。本文选取2005年、2010年、2016年三期TM影像进行遥感解译研究丁字湾地区土地利用变化特征及其空间分布。研究结果表明,丁字湾地区土地利用类型以耕地为主,2005—2016年间建设用地、草地的面积显著增加,水域、海域面积大幅减少。土地的转移主要发生在"建设用地与耕地、耕地与水域、养殖盐田与海域、草地与养殖盐田"之间。城乡建设的不断发展,也给丁字湾地区带来了海岸侵蚀、海水入侵等生态环境负面影响。建议在湾口地区开展"退围还海、退养还滩、退耕还湿"等海岸整治修复工作后,发展人地环境和谐的生态旅游经济。 相似文献
9.
黄河三角洲是陆海交界地带,陆地海洋相互作用显著,泥沙所引起的岸滩演变、港口航道的淤积、水动力环境的改变等问题比较复杂。该文采用三维HEM-3D数值模型对黄河三角洲海域流场变化、盐度、悬浮泥沙浓度及海岸冲淤分布进行了潮流周期内的数值模拟分析。结果表明,黄河三角洲海域的悬浮泥沙浓度分布与潮流场变化和河口泥沙输入有密切的关系,在三角洲北部受五号桩外强潮流区的影响,近岸海底的泥沙发生明显的再悬浮,并在涨潮流向南输送,含沙量达1.5 g/L左右。在三角洲南部(现行河口区域和莱州湾区域),受现行河口入海泥沙扩散的影响显著。海域年冲淤分布,在北部废弃三角洲区域,由于海洋动力作用强烈,浅水冲刷,海底侵蚀显著,形成了明显呈沿岸展布的侵蚀中心,在侵蚀中心以外,侵蚀快速减弱。在现行河口区域,以淤积为主,在羽状流扩散的控制下,泥沙入海后向南输运,至莱州湾区域逐渐减弱。数值模拟的结果与卫星遥感解译的岸线变化基本一致,效果良好。 相似文献
10.
ＴＨＥ ＥＲＯＳＩＯＮＡＬ ＰＲＯＣＥＳＳ ＯＦ ＴＨＥ ＳＯＦＴ ＳＨＯＲＥ ＯＦ ＣＨＩＮＡ ＩＮ ＴＨＥ ＲＥＣＥＮＴ ＤＥＣＡＤＥＳ ＷａｎｇＷｅｎｈａｉ（王文海）；ＷｕＳａｎｇｙｕｎ（吴桑云）；ＸｉａＤｏｎｇｘｉｎｇ（夏东兴）（ＦｉｒｓｔＩ... 相似文献
11.
ESTUARINE AND COASTAL CHALLENGES IN CHINA 总被引：9，自引：0，他引：9
Estuaries and coasts axe conjunctions of four spheres (atmosphere, lithosphere, hydrosphere and biosphere) and important matter and energy convergence/divergence zones, where devel-oped economy, dense population and highly intensive exploitation induce adverse environmental changes and serious destruction of resources, which have great impacts on coastal sustainable development, espe-cially as the highly intensive development in river basins has direct and pronounced effects on estuaries and their adjacent coasts. In the new century, China‘s estuaries and coast are faced with four main chal-lenges : sharp decrease of sediment discharge into the sea, rapid increase of pollution matter into the sea, loss of coastal wetland, and the impacts of global sea level rise on the coastal lowlands of China. There-fore, it is undoubtedly very important and urgent to carry out studies on estuarine and coastal environmen-tal changes, in order to resolve the issue of national sustainable development, especially that of rational use of coastal zone resources. 相似文献
12.
Cuiping Kuang Yue Ma Binyu Wang Jueyi Sui Jie Gu Jianhui Liu Gang Lei 《中国海洋大学学报(英文版)》2018,17(6):1290-1300
Breakwaters can be used as artificial headlands in beach nourishment to mitigate coastal erosion. Longfengtou Beach, located on the southwest coast of Haitan Bay facing the Taiwan Strait on the northeast, suffers severe erosion, where the monsoon causes significant season hydrodynamic variations. Headland breakwaters are intended to be employed to mitigate coastal erosion. A 2D sediment transport model is established using MIKE21 based on current-wave coupling and calibrated by measured data. Summer and winter wave conditions are chosen as characteristic weak and strong waves respectively. The numerical results of suspended sediment concentration and seasonal morphological evolution are compared under the conditions with and without the headland breakwaters. Sediment transport in summer can be regarded as mainly determined by current field, while in winter wave effect is strong enough to change current field. The northern breakwater, nearly perpendicular to the ebb current direction, obstructs the currents and decreases velocity of the ebb currents, and confines the water carrying sediments within the protection area during the flood period. The southern breakwater also breaks the waves in advance and significantly reduces the hydrodynamic effects during the flood period and maintains high suspended sediment concentration in the protection area. In general, two headland breakwaters decrease the erosion near the beach and enlarge the deposition area, which play a significant role in prevention of sediment loss in nearshore area and mitigate coastal erosion. 相似文献
13.
Vuong Van Bui Daidu Fan Dac Ve Nguyen Dinh Lan Tran Duc Thanh Tran Van Long Hoang Thi Hong Hanh Nguyen 《中国海洋大学学报(英文版)》2018,17(6):1272-1280
Coastal erosion has become a worldwide concern, typically in the densely populated Asian mega-river deltas. Severe coastal erosion in the southern Red River Delta(RRD) has been intensively studied. Coastal morphological change in the northern RRD was examined in detail through DEM(Digital Elevation Model) analysis based on time series of bathymetrical maps(1965–2004) and Landsat images(1975–2015) in this study. The results show that the northern RRD is featured by rapid coastal accretion in the past few decades, although suspended sediment flux has dropped by roughly 60% after the completeness of Hoa Binh Dam(HBD) in 1988 and relative sea level rose at 1.9 mm yr~(-1). However, accretion at the outer part of subtidal shoals and platforms was observed to slow down quickly or even turned into erosion in the last two decades. The resuspended sediments from the erosion zone can be transported landward to replenish the inner coastal zone, keeping the latter accretion in the near future to compensate for the sediment discharge decrease from the river. However, this lag effect should be terminated soon if other adverse effects go worse, e.g., damming rivers, sea-level rising, strengthening storms, land reclamation and other poor-designed coastal engineering. Coastal planners and managers should pay full attention to these changes. 相似文献
14.
伴随全球气候变暖导致的海平面上升及沿海地区对地下水资源的超量开采,将会诱发海咸水入侵内陆地下水,导致海陆过渡带的迁移,影响区域社会经济及水资源安全。该文以山东半岛蓝色经济区为研究背景,选取区域内龙口、招远滨海区域作为研究区,首先对研究区内的地下水流场规律进行刻画,然后以模拟因子,对目前地下水超采情景下的海陆过渡带迁移规律进行量化分析研究,研究结果表明:龙口、招远滨海区域海陆过渡带的宽度约为1.5～4.5km,且内陆地下水位越高,海陆过渡带向内陆迁移的速度越慢、范围越小。该成果对研究山东半岛蓝色经济区海陆过渡带的迁移具有重要指导意义。 相似文献
15.
Type and evolution of landscapes of Nansha Islands 总被引：1，自引：0，他引：1
赵焕庭 《中国地理科学(英文版)》1998,8(2):144-151
ＴＹＰＥＡＮＤＥＶＯＬＵＴＩＯＮＯＦＬＡＮＤＳＣＡＰＥＳＯＦＮＡＮＳＨＡＩＳＬＡＮＤＳＺｈａｏＨｕａｎｔｉｎｇ（赵焕庭）ＳｏｕｔｈＣｈｉｎａＳｅａＩｎｓｔｉｔｕｔｅｏｆＯｃｅａｎｏｌｏｇｙ,ｔｈｅＣｈｉｎｅｓｅＡｃａｄｅｍｙｏｆＳｃｉｅｎｃｅｓ,Ｇｕ... 相似文献
16.
黄河三角洲高效生态经济区是具有国家战略地位的重要生态经济区,该地区的海岸带地处海陆交接地带,属于陆缘海海岸带,生态环境脆弱,区域海岸带地形地貌系统性阐述甚少。在开展该区域生态地质环境调查的基础上,结合实际调查情况及以往文献的研读,对该地区海岸带地形地貌、岸滩地貌类型及特征进行了系统性归纳总结。整个黄河三角洲高效生态经济区的海岸带地貌分黄河三角洲粉砂淤泥质海岸、莱州湾南岸潍北平原区粉砂淤泥质海岸、莱州砂质海岸3个部分。岸滩类型分为黄河三角洲岸段冲淤平衡潮滩、侵蚀潮滩、淤积潮滩3种及莱州湾岸段侵蚀潮滩及侵蚀砂质海滩2种。 相似文献
17.
Zhao Huanting 《中国地理科学(英文版)》1997,8(2):144-151
Landscapes of the Nansha Islands may be divided into five types: tropical marine organism-breeding landscape of reef knoll
like Zengmu Shoal, Wan’an Bank and so on; tropical marine organism-breeding landscape of atoll including all emerged reefs
and most submerged reefs; tropical evergreen arbor-bush forest and phosphorous lime soil landscape of limesand Islets like
Taiping Islet, Nanwei islet and so on; tropical shallow sea marine organism-breeding landscape of southern continental shelf;
tropical oceanic and deep-sea marine organism landscape in middle and north parts of the Nansha Islands area. These five landscape
types may be also summed up as two categories, one is tropical sea landscape including those in shallow and deep sea, the
other is tropical coral reef landscape including those of reef knoll, atoll and limesand islet. This paper outlines the evolutional
model of landscapes of the Nansha Islands. The distribution and evolution of landscape types are related with palaeogeography
and modern environmental conditions. The former shallow sea of the Nansha islands was coastal zone in the Late Pleistocene
epoch. Deep sea is evolved from shallow sea due to long and slow subsidence of crust. Modern coral reefs develop on old reef
top of the Late pleistocene epoch or on baserock of continental shelf in the Holocene due to the rise of sea level in postglacial.
Limesand islet is in the peak of developmental stage. 相似文献
18.
Impact of Human Activities on Depositional Process of Tidal Flat in Quanzhou Bay of China 总被引：2，自引：0，他引：2
WANG Aijun 《中国地理科学(英文版)》2007,17(3):265-269
As a very important component of a coastal system,tidal flats come to be a focus of the studies on land-ocean interaction in the coastal zone because those areas are subjected to intense human activities and are highly sensitive to the global change.The Quanzhou Bay,located along the middle part of Fujian coast of China,covers about 136.4km2,and the area of coastal wetland in the entire bay from intertidal to subtidal with 6m of water depth accounts for 96% of the total area.Seven short cores were collected and divided in situ with the interval of 5cm on the coastal wetlands of Quanzhou Bay on April 19,2006.The sediment samples were scattered and the grain sizes were measured by using Mastersizer 2000.Human beings' activities on tidal flat have disturbed the vertical distribution of sediments in stratigraphic sequence and accelerated the sedimentation rates.Grain size analysis results show that the grain size diameters increase and sediment becomes worse sorted towards the sea under the strong human disturbance;Spartina alterniflora can play a role of trapping the fine sediment;but near the bank,the sediment becomes coarse and there are two peak values on frequency curve influenced by the sandpile.The trough formed by human activities along the coastline changes the transport path of water and suspended sediment.The sediments are transported through the trough and deposit in it during the flood;the ebb flow is retarded by the flow output through the adjacent trough,and the deposited sediment can not be re-suspended;then,the sedimentation rate increases.In situ observation show that the sedimentation rate is about 8-10cm/yr. 相似文献
19.
LIU Jinqing CHEN Xiaoying YIN Ping CAO Ke GAO Fei MENG Yuanku QIU Jiandong LI Meina 《中国海洋大学学报(英文版)》2021,(2)
In this paper, we analyzed the grain size and heavy mineral compositions of 52 surface sediment samples collected from the Kompong Som Bay of Cambodia and the adjacent rivers to depict the marine sedimentary environments and transport processes. Heavy minerals in sediments are dominated by authigenic pyrite, siderite, and tourmaline, with average percentages of 36.52%, 29.02%, and 10.94%, respectively. Two provinces can be divided according to the spatial similarity of minerals. The sediments from Province I, covered by silt grains in the northern bay, are characterized by autogenic pyrite, indicating a weakly reducing environment;whereas in Province II, covered by sand grains in the southern bay, the siderite-tourmaline-authigenic pyrite-zircon-hornblende assemblage occurs, indicating a mild reducing environment and locally oxidizing environment. Most of the sediments in the Kompong Som Bay are introduced from the Preak Piphot River and Srae Ambel River, except that some of them in the south areas come from coastal erosion. Generally, the sediments are difficult to be transported because of the low sediment loads entering the sea and weak hydrodynamic conditions. However, they are transported from the north to the south during the tide ebbing when the hydrodynamic force is much stronger. The sediment distribution and transport patterns are controlled by many factors, including submarine topography, hydrodynamic conditions, the southwest monsoon, land contours, and sediment supply. 相似文献
20.
Lunyu Wu Changsheng Chen Peifang Guo Maochong Shi Jianhua Qi Jianzhong Ge 《中国海洋大学学报(英文版)》2011,10(1):1-8
An effort was made to couple FVCOM (a three-dimensional (3D),unstructured grid,Finite Volume Coastal Ocean Model) and FVCOM-SWAVE (an unstructured grid,finite-volume surface wave model) for the study of nearshore ocean processes such as tides,circulation,storm surge,waves,sediment transport,and morphological evolution.The coupling between FVCOM and FVCOM-SWAVE was achieved through incorporating 3D radiation stress,wave-current-sediment-related bottom boundary layer,sea surface stress parameterizations,and morphology process.FVCOM also includes a 3D sediment transport module.With accurate fitting of irregular coastlines,the model provides a unique tool to study sediment dynamics in coastal ocean,estuaries,and wetlands where local geometries are characterized by inlets,islands,and intertidal marsh zones.The model was validated by two standard benchmark tests: 1) spectral waves approaching a mild sloping beach and 2) morphological changes of seabed in an idealized tidal inlet.In Test 1,model results were compared with both analytical solutions and laboratory experiments.A further comparison was also made with the structured grid Regional Ocean Model System (ROMS),which provides an insight into the performance of the two models with the same open boundary forcing. 相似文献