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1.
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   

2.
采用实测资料分析、潮浪水槽试验、定床模型试验以及已建桥梁对涌潮影响的现场观测等手段,研究了钱塘江下游尖山河段建桥对涌潮景观的影响。研究结果表明,钱塘江河口的喇叭形河湾和庞大的水下沙坎使潮波能量积聚、潮差增大,水深急剧变浅、潮波剧烈变形是形成钱塘江涌潮的主要原因。影响涌潮的主要因素是潮汐、江道地形和治江围涂工程,而建桥不会影响涌潮产生的条件,但由于桥墩的阻水作用,对桥上游500 m范围内的涌潮形态有所影响;当采用合理的桥台设计方案,即阻水面积较小时,对上游涌潮高度的影响仅3 cm左右,故不会影响涌潮的景观。  相似文献   

3.
An interactive three-dimensional chemistry-climate model combining models of the gas composition and general circulation of the lower and middle atmosphere is used to study the impact of changes in extra-atmospheric solar radiative fluxes induced by solar activity on the stratospheric heating and subsequent temperature and ozone variations in the stratosphere and troposphere. The results have shown that a change in the atmospheric radiative heating resulting from variations in solar activity has a direct effect on the temperature and circulation of the atmosphere. Atmospheric temperature variations affect the rates of temperature-dependent chemical reactions, and this is considered the first type of indirect impact of solar activity on the atmospheric gas composition. On the other hand, as a result of the variation in atmospheric heating, its circulation changes, thus affecting the transport of minor gases into the atmosphere. This effect is considered the second type of indirect impact of solar activity on atmospheric gases. The results of our calculations have shown that both types of indirect impact of the variation in solar activity on the atmospheric gas composition are comparable in order of magnitude to the direct impact of solar activity on atmospheric gases.  相似文献   

4.
本文基于南大洋环流研究最新资料,从资料来源、动力模式以及有待解决的问题几个方面较详细地阐述南大洋环流动力学研究动态。  相似文献   

5.
6.
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   

7.
A study was made on the polyculture of the red algae Gracilaria tenuistipitata Chang et Xia f. Liui Zhang et Xia, f. nov. , the shrimp Penaeus penicillatus Alcock and the mud crab Scylla serrata (Forskal) . The photosynthesis of the algae produces the oxygen on which the shrimp and the crab breathe. The algae are the reproductive place of the organism for the food of the shrimp and the carb, also is the shelter of the shrimp and the crab. The shrimp and the crab regard the algae as the vegetable  相似文献   

8.
乐清湾海水增养殖区环境质量状况及分析   总被引:1,自引:0,他引:1  
姚炜民  陈雷 《海洋通报》2007,26(4):116-120
利用2002年至2004年对乐清湾海水增养殖区的海洋环境监测结果,分析和评价了乐清湾海水增养殖区的海洋环境质量状况。结果表明:乐清湾海水增养殖区营养盐超标严重,导致增养殖区整体水质超出四类海水水质标准,与增养殖区应达到的二类海水水质标准不符,影响了增养殖区主导功能的发挥。  相似文献   

9.
钱迈 《海洋学研究》2010,28(2):36-44
我国的《领海及毗连区法》第2条规定:"领海基线向陆地一侧的水域为中华人民共和国的内水"。我国的《海域使用管理法》第2条规定:"本法所称内水,是指中华人民共和国领海基线向陆地一侧至海岸线的海域"。"两法"对"内水"的定义有水域和海域之分,因此容易引起解读上的分歧或执法上的模糊。分歧之一是,根据《海域使用管理法》,从领海基线向陆地一侧至海岸线部分,是否包括河口、海湾、滩涂等"内水";分歧之二是,根据《领海及毗连区法》,是否认定一部分"内水"即内海是由直线基线法所致。为什么"两法"对"内水"有水域和海域两种不同的定义?其一,"两法"针对的客体不同,《领海及毗连区法》针对的客体是国际或国外,该法的主体是国家主权;《海域使用管理法》针对的客体是国内海域,该法的主体是国内海域的使用管理。《联合国海洋法公约》(以下称《公约》)规定"领海基线向陆一面的水域构成国家‘内水’的一部分",那么另一部分"内水"就是正常基线向陆一侧的水域,包括江、河、海湾等,它完全置于国家领土主权之下。其二,用专业术语上的海岸线替代《海域使用管理法》中的海岸线会出现矛盾。专业术语上同指水陆分界线的有海岸线和"干出线"两种。前者是涨潮时离岸最近的线,后者是退潮时离岸最远的线,依据《公约》规定:"测算领海宽度的正常基线是沿海国官方承认的大比例尺海图所标明的沿岸低潮线,即退潮时海水离岸最远的那条线",所以低潮线更加符合《公约》和《海域使用管理法》中海岸线的定义,怎样理解海岸线才不会出现矛盾呢?本文认为,完全意义上的海岸线是大潮高潮线与低潮线之间的一条带状面,这个面有时被水淹没,有时出露,且宽窄不等,陡缓不一。当解读了《公约》的有关条款后,就不难理解领海基线向陆地一侧至海岸线的水域中有盐度为0.05~30和30~36范围的"内水"存在,盐度范围为0.05~30的"内水"是指按正常基线法划定领海基线而出现的"内水",包括水域和海域;盐度范围为30~36的"内水"是指按正常基线与按直线基线法划定的领海基线之间出现的"内水",即内海。它们在法律层面上有主从之分,不能混淆。  相似文献   

10.
The influence of high vertical velocity gradients in the Black Sea Rim Current on the intensity of the vertical turbulent exchange is demonstrated on the basis of numerical modeling based on CTD data. The vertical turbulent exchange is confirmed by the anomalous distribution of the hydrochemical parameters in the redox layer. A system of equations for the kinetic energy of the turbulence and dissipation rate (k-? model) is used for the calculation of the coefficient of the vertical turbulent viscosity (diffusivity).  相似文献   

11.
Backstripping of four marine wells on the northern margin of the Alboran Basin reveals a tectonic subsidence history that varies laterally along the margin from east to west. The well on the eastern margin (AndA1) records a fairly steady, continuous subsidence for most of its history, whereas wells on the western margin (AndG1 and AlbA1) show two distinct phases in their subsidence curves. The form of the subsidence curve for DSDP well 121 reflects its position on a structural high. Beta values for the tectonic subsidence curves range between 1.3 and 1.6.  相似文献   

12.
13.
With the very extensive coastline in the north and northeast and the relatively shorter coastlines in the south, cheniers in the USSR can occur in a great variety of climatological conditions ranging from subarctic to subtropical. Cheniers in the USSR have been studied since approximately 1900, the investigations being mainly concerned with the palaeogeographical aspects. Since the 1960's, investigations have focussed on contemporary morphodynamics. Chenier formation appears to depend largely on the relative influence that marine and fluvial factors have on the formation of marginal deltaic plains. Research in this field is briefly reviewed.  相似文献   

14.
Results of simultaneous measurements of the direct solar radiation flux and of the degree of polarization of visible light scattered at the zenith at a different albedo of the underlying surface covered with snow after heavy snowfalls or having no snow cover are analyzed. The possibility of monitoring air turbidity on the basis of polarimetric measurements is confirmed. A procedure of remote detection of the effect of solar light polarization on atmospheric aerosol is proposed and implemented.  相似文献   

15.
基于卫星遥感影像和水下地形数据,分析了近年来东山岛东南侧的岸滩演变特征。进一步,分别建立潮流、波浪、沿岸输沙数值模型,结合人类活动的影响,分析东山岛东南侧岸滩侵蚀的动力成因。研究结果表明,2002-2012年金銮湾的北侧海域海床侵蚀较为严重;1971-2003年,乌礁湾北侧湾顶呈现出侵蚀现象,2003-2012年,乌礁湾北侧湾顶由之前的侵蚀现象转变为一定的淤积趋势。主要原因如下:(1)岬角的挑流作用使得金銮湾和乌礁湾北侧岬角附近海域流速较大,容易产生冲刷侵蚀。(2)金銮湾和乌礁湾的北部波高较高,波能较大,容易遭受侵蚀。(3)金銮湾和乌礁湾北部海岸输沙强度较大,净输沙方向以自东向西为主,容易发生岸滩侵蚀。(4)20世纪90年代以来,东山岛人类活动强度增大,海滩不合理的人工建筑物、海岸防护林破坏以及养殖场的建造在一定程度上加重了侵蚀。(5)2003年后乌礁湾北侧修建了码头工程,导致近岸潮流和波浪动力有所减弱,使得侵蚀现象转变为一定的淤积。  相似文献   

16.
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   

17.
《Journal of Sea Research》2000,43(3-4):345-356
During spring blooms 1998 and 1999, three complementary methods were used to evaluate the in situ feeding activities of the dominant copepod species of the Belgian coastal zone: gut pigment content analysis using HPLC, the 14C tracer method, and cell count experiments. The results obtained by all three methods consistently showed that Phaeocystis globosa is not an adequate food source for the spring copepods in the Belgian coastal zone. Our results demonstrated that, among the potential prey, copepods strongly selected diatoms and microzooplankton, and that these types of prey accounted for the major part of the ingested carbon. However, diatoms and microzooplankton ingestion did not always seem sufficient in terms of carbon to avoid food limitation. Comparison of clearance rates exerted on different potential prey types during the P. globosa peak with those before and after the P. globosa peak showed that the copepods' feeding pressure on diatoms was reduced during the P. globosa peak while that on microzooplankton was not. The low grazing pressure on P. globosa, together with the preferential grazing on diatoms, which reduces the competition for nutrients, and the predation on microzooplankton organisms, which reduces the microzooplankton grazing pressure on P. globosa cells, are likely to favour the P. globosa bloom in the Southern Bight of the North Sea.  相似文献   

18.
New prognostic estimates are obtained for the potential variability of the atmospheric ozone content in the first half of the 21st century. The calculations are based on models of gas composition and general circulation in the lower and middle atmosphere and on the scenarios of the World Meteorological Organization (WMO). It is shown that the rate of ozone content increase will be controlled to a considerable extent by variations in stratospheric temperature. Even though the contents of atmospheric chlorine and bromine are not reduced, contrary to the WMO prediction, and remain at the present-day levels, the continuation of stratospheric cooling will lead to a rapid recovery of the ozone content to its level characteristic of the 1980s. Model experiments on variations in the stratospheric aerosol content have shown that an increase in the aerosol concentration will not affect the rate of ozone recovery in the atmosphere during reduced emissions of chlorine and bromine gases if the stratospheric temperature remains lowered. Numerical experiments have also shown that the simultaneous anthropogenic action on the contents of halogen gases and on the lower-stratosphere temperature can reduce the adverse effects of Freons and halons on the ozone layer.  相似文献   

19.
Mesoscale inhomogeneities in the fields of wind, temperature, and ozone concentrations have been studied on the basis of aircraft measurements performed within the international EUPLEX and RECONCILE projects in the northern polar region in the presence of the circumpolar vortex. Data have been obtained on the structure of turbulence inside and outside the circumpolar vortex. The zones of enhanced turbulence have been studied. The spectrum of coherence between ozone and wind velocity are found to have high values.  相似文献   

20.
The influence of the sea surface temperature (SST) on the carbon dioxide (CO2) exchange with the atmosphere at different spatial and temporal scales, which has a multidirectional character, was studied. The initial data included the monthly averages of the CO2 flux during the period of 1982–2011 at grid nodes of 4° by latitude and 5° by longitude, as well as the SST satellite data from January 1, 1982 to December 31, 2012 at the geographical grid nodes of 0.25° × 0.25°. Statistical models of estimation of the resulting global CO2 flux were suggested on the basis of data on SST anomalies. It is demonstrated that the SST variations in the equatorial zone mostly control the interannual fluctuations of the resulting CO2 flux in the ocean-atmosphere system.  相似文献   

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