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1.
珠江口内伶仃洋水下地形地貌特征 总被引：3，自引：0，他引：3
夏真 《海洋地质与第四纪地质》2005,25(1):19-24
珠江口海底管线、跨海大桥及港口码头堤坝等近岸海底工程构筑越来越多，为服务于当地的经济发展需要，广州海洋地质调查局使用数字测深仪、多波束水深测量系统和旁侧声纳扫描系统，对珠江口内伶仃岛以北水域(内伶仃洋)的水下地形地貌进行了调查。利用调查资料，分析了内伶仃洋的水下地形地貌特征，认为内伶仃洋水下格局总体上呈三滩两槽分布，发展趋势处于不断的淤浅和萎缩，但人为作用已对水下地形地貌产生了较大的影响，破坏了水下生态环境，应加强水域综合管理，加大环境保护力度。 相似文献
2.
《海洋地质与第四纪地质》2015,(1)
对珠江口内伶仃洋158个表层沉积物样品的粒度资料进行分析,探讨了表层沉积物的特征,并在此基础上应用GSTA模型分析了内伶仃洋河口湾泥沙运移趋势。结果表明,珠江口内伶仃洋表层沉积物共有6种类型,其中以黏土质粉砂分布最为广泛。内伶仃洋河口湾泥沙运移特征较复杂,以东槽和西槽为界,分Ⅰ区、Ⅱ区、Ⅲ区。Ⅰ区在涨落潮流的作用下泥沙总体呈现出向东部岸滩运移的趋势;Ⅱ区往复流强劲,盐水楔活动频繁,受科氏力作用泥沙自东北向西南输运;Ⅲ区横门岛至金星门之间的分流间海湾泥沙呈现出向岸滩运移的趋势,淇澳岛周围泥沙呈现出顺时针方向的环流运移的特点。 相似文献
3.
利用Google Earth(GE)遥感影像资料,完成了对世界沿海国家的围填海分布及平面设计特征的研究。研究表明:世界围填海主要分布在4大区域,即东亚、波斯湾、欧洲西部和北美沿岸;中国的围填海总量最多,平均粒度第二;4大区域的围填海平面形态呈现规律性,东亚填海基本以几何形状居多,波斯湾填海多为仿自然形态,欧洲西部填海善于利用地理区位优势,北美填海有大量突堤游艇码头。讨论了造成围填海平面形态区域差异的原因及本次研究的优缺点,可为围填海管理和围填海平面设计研究提供方法支持。 相似文献
4.
依据不同围填海类型在高分三号(GF-3)合成孔径雷达(synthetic aperture radar,SAR)卫星遥感影像上可分性,建立围填海遥感分类体系及相应的围填海类型解译标志,进而分析SAR图像岸线提取方法,构建GF-3围填海监测技术流程。采用几何主动轮廓模型进行GF-3 SAR影像自动提取海岸线,获得围填海专题图。通过外业精度调查验证GF-3 SAR卫星遥感影像可以有效获取围填海信息。 相似文献
5.
在自然和人为的双重作用下，珠江口伶仃洋地貌特征发生了巨大变化，改变了水动力环境，致使纳潮能力也发生深刻变化。本文以珠江口伶仃洋地貌变化和纳潮能力变化为研究对象，采用近百年来的古地图资料、人类活动和水文特征等资料，通过第四纪地质学、地图学、遥感学、历史地理学等方法，反演内伶仃洋形态变化过程，探讨1906年以来珠江口伶仃洋的地貌变化过程。采用岸线分维数、形状指数、纳潮量、潮差消减能力，定量反映地貌变化对纳潮能力的影响。结果表明，1906-2014年，地形演变造成伶仃洋纳潮量减少了14.50%；1971-2014年，伶仃洋纳潮量减少了11.27%。海岸线的变化引起纳潮能力逐渐变弱，潮差沿程变化率减小了0.23，尤其是自1971年以来，因堤围等建设，河口岸线逐渐平直，纳潮能力逐渐减弱。 相似文献
6.
利用已经过验证的高分辨率三维海洋动力模型FVCOM,根据1984—2014年内伶仃洋的围填海变化情况,结合情景模拟案例,研究分析围填海对伶仃洋水流动力的影响,探究截流式和顺流式围填海对伶仃洋不同季节的水平余流场、垂向环流结构以及潮汐变化过程的影响。研究结果表明,围填海对伶仃洋的余流流向没有明显影响,但对余流速有较大的影响。在水平方向上,截流式围填海使得周边海域的余流速明显增大,增幅在0.02～0.25 m/s不等,其中口门区域受到的影响最大;相较于底层流场,表层流场受围填海的影响相对更大,围填海以南的较远海域在表层出现一条强度逐渐减弱的流速减小带,减幅在0.02～0.15 m/s不等,且影响范围与流场的分布密切相关,在夏季向南延伸,在冬季向西南延伸。顺流式围填海的影响则主要分布在伶仃洋两侧沿岸,并且不同季节的影响特点有一定区别,在夏季使得内伶仃洋东岸海域流速增大,但在冬季使其流速减小,变化幅度均在0.02 m/s以上。在垂直方向上,围填海使口门区域余流的纵向流速梯度增加,并且改变了伶仃洋余流的垂向分布情况,总体表现为远离围填海的海域表、底层余流的流速减小,中上层余流的流速增大;与此同时,围填海大幅度改变了周边海域的横向流速,并且在伶仃水道、矾石水道等区域产生了新的横向环流。围填海使得河口至围填海的余水位明显上升,使得伶仃洋海域的余水位下降,余水位梯度的增大是围填海周边余流速增大的主要原因。另外,围填海影响了伶仃洋的潮汐变化过程。在大潮期间,围填海改变了伶仃洋海域涨落潮时的潮流流速,使得周边海域落急流速增加,较远海域落急流速减小,而涨急流速都减小;同时,围填海使得海域涨落潮时的潮位受到一定影响。围填海最终使得伶仃洋的潮汐相位提前了20～35 min。 相似文献
7.
对珠江口内伶仃洋不同海域3个柱状样沉积物进行的210 Pb测年和重金属分布特征垂向变化分析;研究了近百年来珠江口沉积速率时空变化;探讨了在自然作用和人类活动影响下重金属分布特点和累积因素。结果表明,珠江口内伶仃洋海域东西两岸的沉积物平均粒径4~7.5Φ,横门和深圳海域沉积物敏感组分呈现出显著双峰分布,粗细组分分界线为5.25Φ,淇澳岛沉积物敏感组分不明显,沉积环境较为稳定。基于210Pb测年的CIC模式,获得了各个岩心的现代沉积速率,横门海域沉积速率1.6cm/a,淇澳岛海域沉积速率4.08cm/a,0~70cm深度内深圳西海岸海域沉积速率2.58cm/a,70cm以深沉积速率为4.47cm/a。重金属含量分析表明,Cr、Ni、Cu、Zn和Pb含量从1923—1986年维持较高水平,但是变化不大;1967—1983年的深圳海域和1983—2004年的淇澳岛海域,各重金属元素含量快速上升;进入2000年以后,2003—2005年和2008—2012年,重金属含量呈现逐年减小趋势,2005—2008年则表现为逐年上升;这些变化与沿岸的社会经济发展、重金属入海量紧密相关。 相似文献
8.
《海洋地质与第四纪地质》2016,(1)
对珠江口内伶仃洋不同海域3个柱状样沉积物进行的210 Pb测年和重金属分布特征垂向变化分析;研究了近百年来珠江口沉积速率时空变化;探讨了在自然作用和人类活动影响下重金属分布特点和累积因素。结果表明,珠江口内伶仃洋海域东西两岸的沉积物平均粒径4~7.5Φ,横门和深圳海域沉积物敏感组分呈现出显著双峰分布,粗细组分分界线为5.25Φ,淇澳岛沉积物敏感组分不明显,沉积环境较为稳定。基于210Pb测年的CIC模式,获得了各个岩心的现代沉积速率,横门海域沉积速率1.6cm/a,淇澳岛海域沉积速率4.08cm/a,0~70cm深度内深圳西海岸海域沉积速率2.58cm/a,70cm以深沉积速率为4.47cm/a。重金属含量分析表明,Cr、Ni、Cu、Zn和Pb含量从1923—1986年维持较高水平,但是变化不大;1967—1983年的深圳海域和1983—2004年的淇澳岛海域,各重金属元素含量快速上升;进入2000年以后,2003—2005年和2008—2012年,重金属含量呈现逐年减小趋势,2005—2008年则表现为逐年上升;这些变化与沿岸的社会经济发展、重金属入海量紧密相关。 相似文献
9.
福建围填海及其对海洋环境影响的遥感初探 总被引：2，自引：0，他引：2
把遥感技术应用于海岸带现状的动态研究和遥感海洋环境反演是当前遥感应用的热点之一。文章主要利用美国资源卫星专题扫描仪(thematic mapper,TM)遥感影像研究福建围填海状况及大陆海岸线的变化,通过ENVI、ArcGIS软件对研究区遥感影像进行处理,实现海岸线的自动提取、土地分类,以监测福建围填海的动态变化。通过相同季节的中分辨率成像光谱仪(moderate-resolution imaging spectroradiometer,MODIS)遥感影像反演福建海域海水表层温度及叶绿素浓度等海洋参数来了解围填海对海洋环境的可能影响。 相似文献
10.
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.
V. A. Ivanov S. P. Lyubartseva N. Mikhailova N. B. Shapiro 《Physical Oceanography》2001,11(6):509-524
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.
双壳贝类血淋巴中儿茶酚胺的检测方法初步研究 总被引：1，自引：0，他引：1
研究的目的是探索一种检测双壳贝类血淋巴中儿茶酚胺含量的方法。以栉孔扇贝(Chlamysfarreri)和长牡蛎(Crassostreagigas)为实验对象,研究了取样、抗氧化剂、氧化铝用量以及Tris缓冲液用量等对实验结果的影响。结果表明,高效液相色谱电化学检测器法(HPLC-ECD)可以灵敏高效地对双壳贝类血淋巴中儿茶酚胺进行定性、定量检测。实验表明,取样时间最长不超过1.5min;还原性谷胱甘肽作抗氧化剂效果较好;前处理各试剂与血样量的最适配比为血样量1.5mL,Tris缓冲液(1.5mol/L,pH8.6)1mL和氧化铝25mg;水洗后离心并尽可能吸干氧化铝中的水分。去甲肾上腺素、肾上腺素和多巴胺的回收率分别为53%~69%、47%~73%和48%~56%。 相似文献
16.
The authors have previously determined that the effectiveness and failure pattern of the ice cover caused by flexural-gravity waves generated by a submerged body motion near the bottom ice can greatly depend on the depth of the water area. In its turn, the presence of a ledge on the ice surface may affect a wave propagation pattern. This paper presents an experimental study of the bottom contour influence on the deflection and length of flexural-gravity waves. The authors describe a numerical model for the analysis of the deformed state of ice caused by hydrodynamic loads due to a submarine motion, taking into account the bottom contour. The experiments are carried out in the ice tank. The results of calculations and experiments are compared. 相似文献
17.
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
18.
Relationship between the path of the Kuroshio in the south of Japan and the path of the Kuroshio Extension in the east 总被引：2，自引：0，他引：2
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
19.
为研究黄河入海径流变化条件下河口附近海域盐度扩散特征,以更好地保护河口海域生物资源多样性,本文以黄河下游利津水文站的长序列实测径流数据资料为基础,利用近海水动力模型FVCOM,分析径流变化对黄河口海域盐度的影响规律。结果表明：黄河口与莱州湾之间存在顺时针的环流系统,在余流作用以及涨落潮方向的影响下,黄河冲淡水长期向莱州湾扩散;丰水期黄河冲淡水几乎影响了整个莱州湾,27盐度锋可以到达莱州湾中部,27等盐线的表层包络面积为2 665.61 km2,占莱州湾的1/4左右,枯水期低盐度水只有向南扩散的趋势,27以下的低盐度水集中分布在黄河口门附近,27等盐线的表层包络面积只有199.65 km2;5月份,随着入海径流量增加,27等盐线扩散的范围、距离、方向都会发生明显变化。在对近海生物资源有迫切保护需求的情景下,适当减少其他用水户供水量以增加入海生态径流量,可以有效改善黄河口海域附近的盐度情况,为生物资源的生长繁殖创造良好条件。 相似文献
20.
I. E. Timchenko A. A. Primalenny V. D. Yarin E. F. Vasechkina E. M. Igumnova 《Physical Oceanography》2001,11(4):367-378
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