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1.
This paper discusses remote sensing (RS) of the major types of water bodies by means of microwave radiometry. The analysis is based on theoretical models and experimental data taken under laboratory conditions, in a pool, from a shore, and over the oceans using aircraft and satellites. The radiation is found to depend on wind speed and the geometry of ripples, gravity waves, swell, foam, and some physical and chemical parameters of water such as its temperature, salinity, and concentration of some types of polutants. The estimates of the effectiveness of the microwave radiometric method for determining the above mentioned water-surface parameters are given. Examples of the application of microwave radiometry to obtaining operational information about some of them are also presented. The types of water observed are the inland waters, fresh or with a high concentration of salts, clean or polluted, and the oceans. The paper is based on the theoretical and experimental investigations conducted by the author and his colleagues at the Institute of Radio Engineering and Electronics of the Academy of Sciences in the USSR over the last 20 years. It also draws upon well-known Soviet and foreign publications. 相似文献
2.
《Journal of Sea Research》1999,41(1-2):55-71
Investigations of continental shelf sedimentology can be separated into small-scale sediment–fluid-interaction studies and large-scale sediment-survey techniques. Small-scale studies rely on time-series observations from benthic tripods using current meters, turbidity sensors, CTDs, cameras, and acoustic altimeters and sonars. Large-scale studies rely on repeated spatial surveys using side-scan sonar, acoustic profiling methods, and coring techniques. Over the past four decades these approaches have been very successful in describing the sediments on continental shelves and interpreting the physical forcing mechanisms and resulting sediment transport pathways, depositional sites, sediment budgets, and strata formation. Results from shelf studies carried out off the west coast of North America and the Amazon River are used to illustrate the many insights gained from small-scale and large-scale investigations. Recent developments of new sensors and observational techniques have greatly improved our ability to investigate the sedimentology of continental shelves. The time and spatial scales of resolution for both small-scale and large-scale investigative approaches have begun to overlap, and the possibility of concurrent investigations defines exciting new opportunities for future research. 相似文献
3.
N. Z. Cherkis M. D. Max P. R. Vogt K. Crane A. Midthassel E. Sundvor 《Geo-Marine Letters》1999,19(1-2):131-142
Closely spaced, single-beam bathymetric and side-scan sonar investigations on the northern slope of the western Svalbard
insular platform have revealed the presence of a Late Quaternary slump complex forming a hanging-wall slump canyon near the
head of the Malene Bukta (Malene Bay) bathymetric embayment in the northern continental margin. Repeated slump erosion may
be responsible for development of this young feature and the Malene Bukta Embayment. Focusing of the slumping may be due to
the trapping of gas at shallow sea-floor depths by gas hydrate, with the consequent formation of subjacent gas-rich, low shear-strength
decollement zones. Faults have likely controlled the upward migration of gas into the younger sedimentary prism. 相似文献
4.
Predictions of association constants for ion-pair formation in seawater were compared to measured constants as a test for the existence of ion-pairs. A fair agreement was obtained in most cases, although the theoretical electrostatic calculations indicate that significant chloride ion-pairing should occur which has not been observed in most experimental investigations. 相似文献
5.
Competition within the marine microalgae over the polar dark period in the Greenland Sea of high Arctic 总被引：2，自引：0，他引：2
Abstract-With the onset of winter, polar marine microalgae would have faced total darkness for aperiod of up to 6 months. A natural autumn community of Arctic sea ice microalgae was collected fordark survival experiments from the Greenland Sea during the ARKTIS-XI/2 Expedition of RV Po-larstern in October 1995. After a dark period of 161 days, species dominance in the algal assemblagehave changed from initially pennate diatoms to small phytoflagellates (<20μm). Over the entire darkperiod, the mean algal growth rate was-0.01 d~(-1). Nearly all diatom species had negative growthrates, while phytoflagellate abundance increased. Resting spore formation during the dark period was ob-served in less than 4.5% of all cells and only for dinoflagellates and the diatom Chaetoceros spp. We as-sume that facultative heterotrophy and energy storage are the main processes enabling survival during thedark Arctic winter. After an increase in light intensity, microalgal cells reacted with fast growth withindays. Phytoffa 相似文献
6.
We present the results of biological and oceanographic investigations performed in the Weddell and Scotia Seas within the framework of the first (January–June, 1997) and second (January–June, 1998) Ukrainian Antarctic marine expeditions. We reveal some regularities in the space distribution of the aggregations of krill and salpae depending on the abiotic (hydrophysical) environmental factors and discuss possible mechanisms promoting the formation of aggregations of krill and salpae in the Antarctic waters. 相似文献
7.
N. V. Dmitriev S. M. Likhachev V. F. Raputa V. A. Sukhorukov 《Physical Oceanography》1992,3(2):123-129
The sensitivity of upper mixed layer models developed at the Computer Centre of the Siberian Department, USSR Academy of Science, using oceanographic observations conducted at station C, to seasonal variability of the Prandtl number and short-wave radiance absorption coefficient is studied. A quantitative criterion for estimating the validity of the upper ocean model is suggested.Translated by V. Puchkin. 相似文献
8.
P.Lewis Young 《Marine Policy》1984,8(4):360-363
There are many territorial disputes in Asia — both on continental Asia and in the surrounding seas. These disputes are often extensions of wider ethnic, historical and ideological rivalries. A relatively new development in disputes over island territories and EEZ boundaries is the economic dimension that has been added to old disputes and rivalries: the disputing nations, aware of the benefits that offshore oil and minerals, as well as fishing, can provide to their economies, have a clear financial incentive to pursue their claims as strongly as they dare. National pride and wider political and ideological conflicts with their rival claimants further reduce the prospects for compromise. Tensions are increased by the possibility that a military conflict in pursuit of a claim could lead to escalation, drawing the USA and the USSR into the dispute. This article outlines some of the major tension points in the area of the South China Sea. 相似文献
9.
基于国内外研究成果对西太平洋岛弧-弧后盆地热液活动的分布规律、扩张速率、水深以及热液硫化物的矿物组成与金属品位等特征进行探讨。西太平洋岛弧-弧后盆地热液硫化物区以活动型热液区为主,受扩张速率的影响明显主要分布在20～60 mm/a地区;水深分布规律主要受所处构造单元的水深特征控制,而非由热液硫化物区的形成特征所决定;研究区内的热液产物主要为富Zn-Cu、富Ba-Zn以及富Fe-Cu型硫化物;热液硫化物中冲绳海槽具有最高的Ag、Pb含量,劳海盆具有最高的Zn含量,马努斯海盆和伊豆-小笠原-马里亚纳海槽具有较高的Au含量,北斐济海盆具有最高的Cu含量。本研究将进一步为西太平洋岛弧-弧后盆地地区热液硫化物资源的勘探与潜在资源量的估算提供参考。 相似文献
10.
Despite a number of geotechnical investigations that have been carried out in the Busan new port area of South Korea, the local practicing engineers have been unable to deduce successfully the geotechnical properties of the clays due to their spatial variation. In the area, clay deposits, so-called Pusan clays, are unusually thick, varying from 20 m to 70 m in thickness. For this study, comprehensive geological and geotechnical investigations were carried out with sophisticated sampling techniques, in situ and laboratory tests as well as geological analyses at an additional three locations. As a result of the investigations, it was found that depositional environments are closely related to the relative changes in sea level and have different features depending on location and depth. The clays consist of soft and stiff clays in the upper and the lower layers, respectively, which are classified as normally consolidated and cemented clay. Moreover, most of the geotechnical properties undergo small changes due to their depositional environment. Information about these effects would be quite helpful to understand the spatial variation of geotechnical properties as well as the effect of sample disturbance. Some correlations which reflect the geological history of the deposts were conducted for physical indexes and mechanical properties. 相似文献
11.
A. S. Drofa V. G. Eran’kov V. N. Ivanov A. G. Shilin G. F. Iskevich 《Izvestiya Atmospheric and Oceanic Physics》2013,49(3):298-306
The results of experimental investigations into the action of polydispersion salt powders on model cloud media are presented. The results of experiments show a considerable positive effect of the modification of convective clouds by salt powders in order to obtain additional precipitation. The introduction of polydispersion salt powder into a forming cloud medium leads to the appearance of large cloud droplets and to the droplet-spectrum broadening. This result is a positive factor for the stimulation of coagulation processes and further precipitation formation. No “overseeding” phenomenon (when, instead of the enlargement of droplets, their sizes decrease and the concentration of cloud droplets increases) is observed at rather high mass concentrations of the introduced powder. 相似文献
12.
ABSTRACT Despite a number of geotechnical investigations that have been carried out in the Busan new port area of South Korea, the local practicing engineers have been unable to deduce successfully the geotechnical properties of the clays due to their spatial variation. In the area, clay deposits, so-called Pusan clays, are unusually thick, varying from 20 m to 70 m in thickness. For this study, comprehensive geological and geotechnical investigations were carried out with sophisticated sampling techniques, in situ and laboratory tests as well as geological analyses at an additional three locations. As a result of the investigations, it was found that depositional environments are closely related to the relative changes in sea level and have different features depending on location and depth. The clays consist of soft and stiff clays in the upper and the lower layers, respectively, which are classified as normally consolidated and cemented clay. Moreover, most of the geotechnical properties undergo small changes due to their depositional environment. Information about these effects would be quite helpful to understand the spatial variation of geotechnical properties as well as the effect of sample disturbance. Some correlations which reflect the geological history of the deposts were conducted for physical indexes and mechanical properties. 相似文献
13.
挥发性卤代烃(Volatile halocarbons,VHCs)是大气中一类重要的痕量温室气体和主要的臭氧层破坏者,在全球气候变化中起着十分重要的作用。大量研究表明海洋是大气中VHCs的重要源汇区,研究海洋中VHCs的生物地球化学循环,对于进一步了解海洋中的VHCs对未来全球气候的影响具有重要意义。本文针对国内、外有关海洋中VHCs生物地球化学循环研究的进展进行了综述,介绍了VHCs在海洋中的来源和产生机制、它的分布规律及其影响因素,从而归纳了VHCs在海洋中的迁移转化过程。针对目前缺乏对于海洋中VHCs的生物、非生物形成机制及其在海洋中迁移转化机制的具体过程的深入研究,以及有限航次的海洋中VHCs的浓度监测数据和源汇收支不平衡的问题,提出未来的研究需要加强海洋中VHCs的来源、生成机制、迁移转化机制及其影响因素的深入探究,开展更系统的长时间尺度和空间维度上的全球海域中VHCs大数据监测,并完善海-气通量的计算方法,准确估算海洋中VHCs的源汇。 相似文献
14.
利用强流脉冲(HCPEB)电子束技术对多晶纯Cu进行了辐照处理,并利用透射电镜对HCPEB诱发的空位簇缺陷进行了表征.实验结果表明,HCPEP辐照金属可在纯Cu表层诱发大量的过饱和空位,并形成四方形空位胞及空位型位错圈和堆垛层错四面体(SFT),HCPEB瞬间的加热和冷却诱发的幅值极大的应力和极高的应变导致的整个原子平面的位移是空位簇缺陷形成的主要原因.此外,扫描电镜分析表明HCPEB辐照可以在纯Cu表面形成高密度、弥散分布和尺寸细小的微孔.过饱和空位或空位团簇沿晶体缺陷向表面扩散、凝聚是表面微孔形成的根 相似文献
15.
Numerous studies have been carried out to identify storm deposits and decipher storm-induced sedimentary processes in coastal and shallow-marine areas. This study aims to provide an in-depth review on the study of coastal storm deposits from the following five aspects. 1) The formation of storm deposits is a function of hydrodynamic and sedimentary processes under the constraints of local geological and ecological factors. Many questions remain to demonstrate the genetic links between storm-related processes and a variety of resulting deposits such as overwash deposits, underwater deposits and hummocky cross-stratification (HCS). Future research into the formation of storm deposits should combine flume experiments, field observations and numerical simulations, and make full use of sediment source tracing methods. 2) Recently there has been rapid growth in the number of studies utilizing sediment provenance analysis to investigate the source of storm deposits. The development of source tracing techniques, such as mineral composition, magnetic susceptibility, microfossil and geochemical property, has allowed for better understanding of the depositional processes and environmental changes associated with coastal storms. 3) The role of extreme storms in the sedimentation of low-lying coastal wetlands with diverse ecosystem services has also drawn a great deal of attention. Many investigations have attempted to quantify widespread land loss, vertical marsh sediment accumulation and wetland elevation change induced by major hurricanes. 4) Paleostorm reconstructions based on storm sedimentary proxies have shown many advantages over the instrumental records and historic documents as they allow for the reconstruction of storm activities on millennial or longer time scales. Storm deposits having been used to establish proxies mainly include beach ridges and shelly cheniers, coral reefs, estuary-deltaic storm sequences and overwash deposits. Particularly over the past few decades, the proxies developed from overwash deposits have successfully retrieved many records of storm activities during the mid to late Holocene worldwide. 5) Distinguishing sediments deposited by storms and tsunamis is one of the most difficult issues among the many aspects of storm deposit studies. Comparative studies have investigated numerous diagnostic evidences including hydrodynamic condition, landward extent, grain property, texture and grading, thickness, microfossil assemblage and landscape conformity. Perhaps integrating physical, biological and geochemical evidences will, in the future, allow unambiguous identification of tsunami deposits and storm deposits. 相似文献
16.
通过模拟实验制备了硅酸盐类不溶性固体，从Ｘ射线衍射特征和红外光谱特征两方面看，制得的硅酸盐类与河口新生相成分，结构相似，表明铁水解成的β－ＦｅＯＯＨ胶体吸附Ｓｉ，Ａｌ，Ｍｇ，Ｋ等元素，经结构重组可形成硅酸盐矿物，这可能是河口体系新生相的形成原因。 相似文献
17.
Roniti Teiwaki 《Marine Policy》1987,11(4)
This article highlights the typical problems experienced by the small island states of the South Pacific in negotiating access agreements with the major distant water fishing nations (DWFNs), notably the USA, Japan, South Korea and the USSR. The article is a post mortem of the Republic of Kiribati's experience with the DWFNs during the period from 1979 to 1986. 相似文献
18.
G. A. Cherkashev V. N. Ivanov V. I. Bel’tenev L. I. Lazareva I. I. Rozhdestvenskaya M. L. Samovarov I. M. Poroshina M. B. Sergeev T. V. Stepanova I. G. Dobretsova V. Yu. Kuznetsov 《Oceanology》2013,53(5):607-619
The optimal set of prospecting methods, including geophysical (geoelectrical), geological (mineralogical-geochemical), and hydrological observations, was developed during the long-term investigations of the sulfide mineralization in the northern equatorial zone of the Mid-Atlantic Ridge. The application of these methods made it possible to discover six massive sulfide deposits and considerably extend the boundaries of another two ore objects. The ores associated with ultramafic rocks are characterized by elevated Cu, Au, and Co concentrations. It is established that the ore formation was a multistage process that resulted in the accumulation of large deposits (over 10 million tons). 相似文献
19.
We perform the theoretical analysis of the turbulent diffusion of impurities in the sea in the presence of long waves. The role of generators of long-wave motions is played by moving cyclonic baric formations. At the initial time, the zone of pollution is specified in the form of a spot of a passive substance localized near the Karkinitskii Bay in the Black Sea. The results of our investigations enable us to estimate the contribution of long waves to the process of diffusion of the spot of impurity depending on the trajectory of motion of the cyclonic formation. It is shown that, under the action of waves induced by the cyclone, the maximum concentration in the spot decreases more rapidly only for a certain period of time. Moreover, we observe a northwest displacement of the spot specified by the structure of the wave field.Translated from Morskoi Gidrofizicheskii Zhurnal, No. 4, pp. 3–18, July–August, 2004. 相似文献
20.
In this paper some results obtained in the course of investigations of the hydrological and hydrochemical peculiarities of the tidal frontal zone and of the upwelling's frontal zone in the Guinean shelf area are reported. We have confirmed a direct influence of these zones on the bioproductive properties of the sea-water, suspension distribution, and the types and composition of bottom sediments.Translated by Vladimir A. Puchkin. 相似文献