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1.
文章利用1985、1995、2005、2009年的Landsat卫星遥感影像和2015年的GF-1卫星遥感影像,分析近30年来图们江口海岸线的变化特征。结果表明:近30年来图们江口海岸线长度整体呈增长态势,累积增加0.66km,主要由人类开发活动及泥沙堆积等引起;人工岸线比例增大,但1985—1995年因河流改道致使岸线减少3.8km。1985—2005年海岸带淤积面积大于侵蚀面积,其中河流改道使1995—2005年淤积面积达到4.522 7km2;2005—2015年侵蚀面积大于淤积面积;2005—2009年径流量减少使侵蚀面积达到4.203 7km2。河口处的岸线迁移变化最大,其他地区较稳定。  相似文献   

2.
围填海是区域社会经济发展到一定阶段向海洋谋求发展空间的一种基本手段。珠江三角洲是我国社会经济发展的热点区域之一,探索其近岸河口区域围填海时空过程并对其未来趋势进行分析对海岸带综合开发具有重要的意义。本研究以多源陆地资源卫星Landsat为数据源,通过影像数据处理分析探讨了珠江口围填海历史变迁过程,并对其围填海生命周期进行了估计。结果表明,珠江口围填海主要发生在改革开放后,其中1978—1988年围填海面积为18 572hm2,1988—1996年间围填海面积为25 528hm2,1996—2005年间围填海面积为13 911hm2,2005—2015年间围填海面积6 723hm2。截至2015年,珠江口共围填海面积64 753hm2,空间上主要集中分布于西部岸段。基于历史围填海时空演变过程,通过围填海生命周期图进一步对珠江口未来的围填海工程实施潜力进行形式预判。结果显示,珠海岸段和深圳前海岸段是珠江口今后实施围填海热点区域,其他区域围填海速度会相对减缓,但随着珠江口海岛逐渐与陆地海岸带相接,该区域围填海过程也将会终止。围填海生命周期分析可为海岸带实施围填海工程规划提供相关决策依据。  相似文献   

3.
基于1995、2005、2015年3期遥感影像,在ENVI和Arc GIS软件的支持下,对山东半岛东部近20a来的养殖水面面积及质心变化情况进行了分析,研究结果表明:(1)1995~2015年,养殖水面面积总体呈现增长趋势,共增加425.06 km~2.其中养殖池面积在1995~2015年增加了83.41 km~2,增加的面积主要集中在丁字河口、郝庆口、五垒岛湾、太平湾.在2005~2015年近10 a间养殖池面积呈现明显减少趋势,共减少40.43 km~2,主要集中在五垒岛湾、太平湾.浮筏养殖和网箱养殖在近20a来面积以增加为主,共增加了382.08 km~2,主要集中在套子湾-芝罘湾-金山湾-郝庆口沿海海域,以及乳山口-五垒岛湾-靖海湾等海域.(2)养殖池面积先增加后减少的主要原因是:海鲜市场的大量需求导致1995~2005年养殖池面积迅速增加,由于环境保护以及旅游经济的需要,导致2005~2015年养殖池面积下降;浮筏养殖和网箱养殖面积的持续增加主要受海鲜市场需求及政府政策激励的结果.(3)近20a间,养殖池质心变化不大,共向西南方向偏移9.03 km;浮筏养殖和网箱养殖质心变化较大,共向西南方向偏移了15.24 km,由原来的荣成市偏移到了文登市,浮筏养殖和网箱养殖质心的偏移主要受乳山口、五垒岛湾、靖海湾海域的浮筏养殖和网箱养殖的养殖力度加大的影响.  相似文献   

4.
通过对崇明东滩水文、泥沙、地形等资料的分析,阐述1983-2003年崇明东滩冲淤演变过程. 1.1983-2001年,崇明东滩淤涨延伸较快,0m以上各等高线大幅度向外扩展,沿正东向年均外移228~279m不等.潮滩面积稳定增长,3.5m以上面积增加最多,达65.2km2,0m以上面积共增加8.4km2.滩面淤高迅速,尤其是高潮滩,且有随高程的降低,淤高速率下降的趋势.2. 2003年与2001年相比,崇明东滩0m以上面积增加4.2km2,2.0m以上面积减少0.8 km2,3.0m以上面积年均增长率下降.3.人类活动(如围垦)对崇明东滩的演变产生重要影响.流域来沙量大幅减少对潮滩演变的影响有待于进一步研究.  相似文献   

5.
本文选取1985?2018年间具有代表性的6期Landsat遥感影像,运用数字海岸线分析系统,综合利用面积法和基线法定量分析海州湾的岸线变迁,并进行岸线分类和驱动力分析。结果表明,30多年来海州湾岸线整体呈持续向海推进的态势,增长岸线比例总体处于不断增加的趋势,除了2005?2009年发生短暂的减小;1985?2018年,岸线长度增加了10.40 km,陆域面积增加了52.84 km2;海州湾岸线以人工岸线为主,且比重日渐增大,从1985年的47.90%到2018年的70.88%,前中期的沿海围垦养殖及后期的围海造陆是海岸线变迁的主要驱动力;其终点变化速率为26.09 m/a,净海岸线变化为155.12 m,记录增加总横断面在各个时期均大于50%,岸线变迁最剧烈的区域为新沭河?高公岛段,陆域增长点在于赣榆新城、连云新城建设和连云港港口建设。  相似文献   

6.
胶州湾近期海岸线、水深变化研究   总被引:2,自引:0,他引:2  
以胶州湾1952,1985和2005年的海图为依据,对海岸线位置、海岛、海礁、等深线及水深等自然信息数字化后,对胶州湾近期海岸线、水深的变化进行了分析.研究表明,1952年至今胶州湾海岸线由自然岸线向人工岸线不断转化,岸线长度一直呈现为减少的趋势;1952年至今胶州湾海岸线长度减少了30.39%.1952-1985年之间胶州湾2,5,10 m水深区域面积减小,而20 m水深区域面积基本保持不变.而1985-2005年之间胶州湾2 m水深区域面积有少量减小,但5,10,20 m水深区域面积均有少量增加.水利工程、围海工程和自然环境的变化是引起胶州湾岸线和水深变化的重要原因.  相似文献   

7.
徐孟  刘大海  邢文秀  李森 《海岸工程》2019,38(2):154-164
运用耦合协调模型和空间相关性模型研究了2006—2016年53个沿海城市的经济发展与生态环境协调关系的时空演变趋势、重心迁移、空间相关性。结果表明:我国沿海城市经济发展与生态环境的协调发展状况总体呈向好态势,但总体协调度不高,仍处于协调发展的初级阶段;协调度发展存在严重的空间不均衡性,且呈逐步扩大态势,高值区域主要分布在省会城市和计划单列市,而其他大部分城市仍处于失调状态;2006—2016年协调度重心均位于浙江省金华市,并逐步向西南方向迁移;全局Moran’s I指数和局部Moran散点图显示协调度在空间上呈现明显的正相关,空间集聚性较强。  相似文献   

8.
海岸带是受全球气候变化及人类活动影响最大的地带。本文主要依托谷歌地球平台提供的时序高分辨率卫星遥感影像,提取了 2010-2017 年珠江河口地区海岸线信息,对不同时期的海岸线长度、类型及围海造地面积的变化情况进行了统计分析,对引起变化的驱动机制进行了探讨。结果表明: (1) 2010-2017 年珠江河口海岸线呈现先减少、后缓慢增长趋势。2010-2011 年由于海面整治工程,海岸线长度略微缩减,2011-2013 年为快速增长阶段,2013 年后海岸线长度变化不大,略微呈现增长; (2) 在基岩海岸线、砂砾质海岸线、淤泥质海岸线、人工海岸线、生物海岸线五种海岸线类型中,人工海岸线最长,占总长度的比例始终在 85 %以上,年均正向变化强度最大,达到 0.28 %,呈现稳定扩展趋势;淤泥质海岸线的负向变化强度最大,为-0.28 %,呈现稳定萎缩趋势; (3) 围海造地面积呈增加态势,年均变化面积为 0.25 km2;引起围海造地面积增加的主要原因为港口和码头建设。  相似文献   

9.
以象山港海岸带为研究区域,利用1985年,1995年,2005年和2015年4期TM遥感影像数据,将土地利用类型分为8大类,通过计算土地利用类型动态度、土地利用转移矩阵、土地利用结构信息熵以及土地开发利用强度综合指数4种指标模型,分析了象山港海岸带1985-2015年土地开发利用的速度、结构、程度以及时空变化。结果表明:(1) 1985年到2015年象山港海岸带养殖用地及盐田扩张速度最快,动态度最高可达11.97%,建设用地扩张速度次之,但面积增幅最为显著,滩涂缩减速度最大,耕地面积明显减少;(2) 30年间土地类型主要转变方向为耕地转为建设用地,其次为林地转变为耕地;(3)信息熵逐时期增加,土地利用结构均质性不断加强,区域发展在逐渐走向成熟;(4)各时期土地利用强度指数变化率均大于零,象山港海岸带土地开发利用强度不断增强。  相似文献   

10.
为了分析珠江口区域海岸线近年来的发展变化情况,文章基于分形理论,分别对珠江口及深圳段大陆海岸线2005-2019年的变迁趋势采用网格法进行分形分析,得出14年间,珠江口及深圳段海岸线分维数的变化情况。通过对计算结果的分析对比发现,近年间珠江口海岸线整体因开发强度大,人工岸线居多,分维数值变化较小;而深圳段海岸线分维数较整个珠江口有较大幅度增加。深圳段海岸线曲折度提高的原因主要为修复类工程的实施。海岸线分形维数与海岸线曲折程度的正相关系,与海岸带开发利用规划管理要求相符,提出分维数可作为规划用海的重要评估参数。  相似文献   

11.
The analysis of the structure of the cryolithozone, facies, and thicknesses of the Quaternary sediments and the results of the physicochemical mathematical modeling of the modern shelf of the western part of the Laptev Sea support the influence of the Late Pleistocene glaciations on the heat conditions and the distribution of the permafrost in the area. A ~200-m thick glacier formed under aerial conditions from atmospheric precipitation represented the metamorphosed snow cover. According to the modeling, the long-living (from 60?50 to 10?4 ky) glacier reduced the thickness of the permafrost rocks in the reviewed shelf area for 280–360 m. The Holocene marine transgression additionally decreased the thickness from 50–140 m on the inner shelf to 220–350 m on the outer shelf. The modern submarine cryolithozone 450-0 m thick is wide-spread in the studied region from the coast to the shelf boundary (isobaths of 130–140 m), where it pinches out at a distance of ~380 km from the coast at a depth of ~250 m above the sea level.  相似文献   

12.
We analyze the components of the carbon system of the Sevastopol bay waters and the balance of main sediment-forming substances using the data of field investigations in 1998–2008. The interannual variations of total inorganic carbon and the equilibrium partial pressure of carbon dioxide in the bay water are noted. An increase in the flux of carbon dioxide into the bay and in the content of organic carbon in bottom sediments is revealed, and an explanation of this phenomenon is given. The priority accumulation of organic carbon in the sediments of the bay is established. We assess the interannual variation in the relative abundances of organic and inorganic carbon as an index of the carbon cycle stability.  相似文献   

13.
We generalize and analyze the state of investigations of the influence of river waters on the hydrologic structure of the Black Sea. Specific features of the water, regime and hydrography of rivers flowing into the sea, data on the discharge of rivers, and intrayear and interyear variability of the discharge are presented. We discuss and analyze works studying the transformation of river waters, routes of desalinized sea waters, and their influence on the thermohaline structure and dynamic regime of the sea. Translated by Peter V. Malyshev and Dmitry V. Malyshev  相似文献   

14.
We analyze the results of numerical calculations performed according to the three-dimensional interdisciplinary model of an ecological system of the Black-Sea shelf zone near the estuary of the Danube. The complete system of equations of hydrothermodynamics is solved together with transport equations of the advection-diffusion-reaction type used to describe the transformation of a substance (nitrogen) between the components of the characteristic vectors of the ecosystem: plankton, detritus, and biogenic elements (nitrates). We describe the distinctive features of the circumcontinental distribution of components obtained as a result of numerical experiments and present arguments for the conclusion that the ecosystem of the Danube estuary water area plays the role of a buffer zone between the press of the Danubian biogenic pollutions and the neighbouring areas of the shelf zone and open sea. Translated by Peter V. Malyshev and Dmitry V. Malyshev  相似文献   

15.
Ten years of semistationary studies of the interaction of the ice cover and the coastal relief of the Kandalakhsa Gulf in the White Sea allowed us to reveal the peculiarities of these processes in the warm and cold years and the mechanisms of the origination of ice forms, including ice tents, which govern the character of the tidal flats. Three dynamic fast ice zones are distinguished by their geomorphological location, morphology, and ice dynamics. The dependence of the mechanisms and volumes of the enrichment of the fast ice in the sediments on the coastal zone??s relief was established. At the coast of the Kindo Peninsula (Velikaya Salma Strait), the ice mostly contains fine-sandy sediments. Coarser sediments, including boulders, are occasional and frozen into the ice at the contact of the fast ice and the bottom. At the expense of the ice??s spreading by 4?C6 times in the warm years and 2?C4 times in the cold years, several thousand tons of sediments mostly from the tidal flat??s surface (100?C700 m3 from 1 km of coast in the wide tidal flats and <50 m3 on the steep coasts) are delivered to the water area.  相似文献   

16.
A relationship between paths of the Kuroshio and Kuroshio Extension (KE) is investigated, using the satellite-derived altimetry dataset of 1993–2008. When the Kuroshio takes the nearshore nonlarge meander path or typical large meander path and resultantly goes through the deeper channel (about 2500 m) of the Izu-Ogasawara Ridge, the KE path adopts a relatively stable state with the two quasi-stationary meanders. On the other hand, when the Kuroshio takes the offshore nonlarge meander path and then passes over the shallower part of the Ridge (about 1000 m), the KE path tends to be convoluted, i.e., an unstable state.  相似文献   

17.
We use many-year archival observations of hydrologic and hydrobiologic state of the Sea of Azov for the identification of the structure of a model of its ecosystem. The ecosystem model, supplemented with expert estimates of bioresource consumption (fish reserve), contamination level, and possible ecologic fines for violation of the sea natural state, is formalized by the method of system dynamics. Hereat, the major part of influence functions is found in terms of observational data with application of self-organization algorithms. We also present the results of simulated experiments with the model of the ecosystem, which enable us to analyse scenarios of its behaviour under the influence of various external factors (wind, river discharge, water exchange with the Black Sea, etc.). Translated by Peter V. Malyshev and Dmitry V. Malyshev  相似文献   

18.
Three mathematical models are considered: a two-dimensional model for calculating the concentration fields of the ecosystem components on the shelf of the Republic of Guinea, a pointwise model for the annual variation of the components, and a two predators-prey model. These models are used to study the effect of hydrodynamic conditions on the state of the shelf ecosystem and for research into the causes which distort the balance between marketable and unmarketable fish.Translated by Mikhail M. Trufanov.  相似文献   

19.
The first data on the temporal evolution of the slope of the buried depression of the Black Sea are obtained. The sharp change in the rate of the decrease in the slope steepness that occurred in the Late Miocene-Pliocene time reflects a reorientation of the vector of mutual movement and a related intensification of the collision between the Arabian and Eurasian lithospheric plates.  相似文献   

20.
The stages of the development of the basin of the Bransfield Strait   总被引:1,自引:0,他引:1  
The study of the sedimentary body of the Bransfield Strait has made it possible to identify several sedimentary complexes, to construct the first electronic charts for the acoustic basement, and to establish four stages of the evolution of its floor, which updates the previous knowledge about the formation of the strait. At the first stage, there was an increase in tension stresses that were accompanied by the local splits of the continental crust at the periphery of the Antarctic Peninsula. At the second stage, a graben-like structure filled with the Lower stratigraphic complex was formed northward of the Antarctic Peninsula. At the third stage, the continuing processes of extension led to intensive explosive activity of the growing volcanic structures and filling of the graben with sediments of the Middle seismostratigraphic complex. The fourth stage, which has continued until recently, is characterized by quasi-linear localization of the major centers of volcanic activity in the band closer to the South-Shetland Islands and the formation of the Upper seismostratigraphic sedimentary complex. The evolution of the floor of the Bransfield Strait reflects the process of penetration of the American-Antarctic ridge to the continental lithosphere of the Antarctic Peninsula for the last million years.  相似文献   

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