共查询到20条相似文献，搜索用时 31 毫秒
1.
S. I. Kondrat’ev 《Physical Oceanography》2010,20(2):136-148
We discuss the influence of hydrophysical and biological-chemical processes on the distribution of dissolved oxygen in waters
of the Sevastopol bay in various seasons. In the winter period, against the background of low rates of biological-chemical
processes, the hydrophysical processes provide the homogeneous distributions of temperature and oxygen. In summer, the hydrophysical
processes remain dominant, but the influence of biological-chemical processes becomes noticeable. In the autumn period, the
vertical distribution of oxygen is strongly affected by biological-chemical processes. 相似文献
2.
We discuss specific features of the space distribution and the processes of assimilation and oxidation of the dissolved and emulsified fractions of oil hydrocarbons in Black-Sea waters and study the methods of parametrization of these processes proposed in the literature. We develop a procedure of parametrization of the processes of degradation of oil hydrocarbons taking into account their complex chemical compositions, characteristics of chemical and microbiological processes, and temperature dependences of these processes and perform numerical experiments aimed at the reconstruction of the seasonal variations of the large-scale space structure of the distribution of oil hydrocarbons in the aerobic zone of the Black Sea. 相似文献
3.
4.
5.
夏季越南东北外海暖水的时空变化特征及其机理研究 总被引：1，自引：1，他引：0
Due to orographic blockage, a weak wind wake occurs in summer off northeast Vietnam in the South China Sea. Under the wind wake, warm water is observed from both high-resolution satellite data and hydrographic observations. The wake of warm water forms in June, continues to mature in July and August, starts to decay in September, and disappears in October. The warm water wake also shows robust diurnal variation – it intensifies during the day and weakens in the night. Warm water wakes can be generated through wind-induced mixing and thermal(latent heat flux) processes. In this paper, a mixed layer model is used to evaluate the relative importance of the two processes on seasonal and diurnal timescales, respectively. The results demonstrate that thermal processes make a greater contribution to the wake than wind-induced mixing processes on a seasonal timescale, while the warm water wake is dominated by wind-induced mixing processes on a diurnal timescale. 相似文献
6.
A. A. Lushnikov V. A. Zagaynov Yu. S. Lyubovtseva A. D. Gvishiani 《Izvestiya Atmospheric and Oceanic Physics》2014,50(2):152-159
The level of cosmic radiation has been shown to affect the rate of nanoparticle formation from gas emissions of natural and anthropogenic origins. The acceleration of particle formation processes is mainly caused by the increased concentration of atmospheric ions, which serve as condensation nuclei and thus strongly change the rate of aerosol charging processes. This paper provides a brief overview of the main processes leading to the formation of nanoparticles in the atmosphere. These processes include nucleation, condensational growth, charged particle growth, charging of aerosol particles, and recombination. Particular emphasis has been placed on the role of particle sizes in charging processes. Also, we discuss the influence of aerosol sinks on the rate of aerosol formation. 相似文献
7.
Alan Wood 《Marine Geology》1976,22(1):M23-M29
The observations reported here were made over a period of twenty-two months encompassing six field seasons. the present study demonstrates the highly variable nature of sedimentary processes during different seasons of the year and sometimes from year to year in an area characterized by two different monsoonal phases. Depositional processes characterize one monsoonal phase and erosional processes dominate the other. Lond-term environmental monitoring of sedimentary processes is especially appropriate when extending acceptable uniformitarian criteria to the study of ancient sediments. Conclusions made from short-term studies can give an erroneous view as to the overall nature of sedimentary processes in these areas. 相似文献
8.
9.
Francisco E. Werner John A. Quinlan Brian O. Blanton Richard A. Luettich Jr. 《Journal of Sea Research》1997,37(3-4)
A review of the physical processes present in coastal regions and their effect on pelagic stages of flatfish populations is presented. While quantitative understanding of processes affecting cross-shelf transport and exchange continues to be a fundamental problem shared by physical oceanographers and fisheries scientists studying the early life history of flatfish, advances in hydrodynamic and coupled physical-biological models have made it possible to begin to examine population-level implications of environmental processes. There is now a need to rank these processes in terms of their impact on recruit strength. Existing paradigms provide testable frameworks for explaining the role of physical variability in the observed population patterns, abundance and variability. Identifying explicit links between physical variability and recruitment could result in new approaches to fisheries management strategies. 相似文献
10.
S. M. Govorushko 《Izvestiya Atmospheric and Oceanic Physics》2012,48(8):771-784
The significance of meteorological processes and phenomena in the biosphere functioning is revealed. The influence of various weather conditions on human health is considered; the factors and mechanisms of their action are described. The impact of meteorological processes on animals is discussed and concrete examples of such impacts are presented. The influence of meteorological processes and phenomena on plants at different stages of their life (pollination, growth, ripening, transport of seeds, damage, and death) and on some abiotic natural components is shown. It is inferred that weather-climatic conditions have a great influence on biospheric processes. 相似文献
11.
《Deep Sea Research Part I: Oceanographic Research Papers》2000,47(5):937-970
A biomass-based ecological model is presented here for the Adriatic Sea. The hydrodynamical part is composed of the Princeton Ocean Model, while the European Regional Seas Ecosystem Model describes the biogeochemical processes. An idealized Adriatic basin geometry has been used, with perpetual year seasonal cycle forcing the hydrodynamics and river-borne nutrient input forcing externally the biogeochemical processes. The simulation results highlight the role of the physical processes in determining and maintaining some of the nutrient and phytoplankton biomass distribution and characteristics in the basin. The characteristics of the phytoplankton seasonal cycle have been found to depend, in order of priority, on the river-borne nutrient input and physical horizontal and vertical processes. 相似文献
12.
Peter P. Sakalowsky 《Marine Geology》1975,18(1):M35-M43
On the north side of Napatree Beach, short-term changes of the beach-face within the intertidal zone were studied to determine those processes most influential in causing change where nearshore processes are low in magnitude and beach changes are subtle. The data were subjected to multiple linear correlation and stepwise multiple-regression analyses.Tide level accounts for 41% of the explained variation for the relationship between the processes and beach height. Tide level is the only significant element effecting change in the beach profile. Wave height has no influence on changes in beach morphology. Significant results of beach energy associations have been obtained where low-amplitude nearshore processes are present even when beach changes are subtle. 相似文献
13.
微生物碳酸盐岩研究:回顾与展望 总被引：11，自引：0，他引：11
在查阅国内外大量文献资料的基础上,回顾与综述了微生物碳酸盐岩近几年的研究现状及进展。微生物碳酸盐岩是由钙化微生物(蓝绿菌、微藻等)在微生物作用、沉积作用及成岩作用的共同作用下形成的,其种类繁多,包括叠层石、凝块石、树形石、均一石、核形石和纹理石等。它在各个地质历史时期均有发育,但主要繁盛于中新元古代和早古生代;自显生宙以来,随着后生动物的繁育微生物碳酸盐岩总体呈衰退趋势。另外,微生物对白云石的直接沉淀、碳酸盐泥丘及第五类原生沉积构造的形成具有重要作用。近年来,对微生物碳酸盐岩研究的发展使得碳酸盐岩的成因及分类得到了补充与完善。 相似文献
14.
John M. Huthnance 《Progress in Oceanography》1995,35(4)
The coastal ocean meets the deep sea at the continental shelf edge. Questions of global change entail elucidation of the processes that determine the quantities, transformation and fate of materials transported between the shelf and ocean, the measurement and definition of exchange processes, and the development of prognostic models of exchanges.Physical processes control the large-scale movement and irreversible small-scale mixing of water and its constituents. At the shelf edge, steep bathymetry may inhibit ocean-shelf exchange, but in combination with stratification gives rise to special processes and modelling challenges.A preliminary assessment is made of coastal-trapped waves; along-slope currents, instability and meanders; eddies; upwelling, fronts and filaments; downwelling, cascading; tides, surges; internal tides and waves as potentially influential processes in ocean-shelf exchange, water-mass structure and general circulation, according to their scales and context. For this purpose, theory and previous measurements are interpreted.Future studies needed to improve this assessment are discussed. 相似文献
15.
2021年春季(3—5月)的大气环流特征为:北半球极涡为偶极型分布,极涡较常年平均值偏强,中高纬度西风带呈现4波型。3月,南下冷空气活动偏弱,月内海雾过程频发。4月,北部海域受高压影响,低层形势场稳定,冷空气活动减弱。5月,我国近海受温带气旋影响出现大风天气。春季我国近海出现了5次8级以上大风过程,其中冷空气大风过程2次,冷空气和温带气旋共同影响的大风过程1次,温带气旋影响的大风过程2次。春季共有8次海雾过程,3月3次,4月2次,5月3次。近海浪高在2 m以上的海浪过程有8次,大浪日数偏少。西北太平洋和南海共生成2个台风。我国近海的海面温度整体呈上升趋势,东部和南部海域升温明显,南部和北部海域海面温度梯度增加。 相似文献
16.
《Marine Policy》2014
In line with international commitments to secure human wellbeing via conservation, many nations have set deadlines to implement ecologically coherent networks of Marine Protected Areas (MPAs). However, progress towards achieving these targets is slow. To influence the discourse on the societal need for MPA networks a matrix approach is used to determine the potential for conservation features within the UK proposed network of 127 MPAs to deliver beneficial ecosystem processes and services. The results suggest a non-uniform distribution of ecosystem services across the network, with the majority of MPAs containing conservation features with the potential to deliver ecosystem processes. Designation of the full recommended network of MPAs may provide a form of ecological insurance against further decline in the delivery of beneficial ecosystem services and may also contribute to wider ecological health by supporting broadscale ecological processes. Non designation of MPAs that contain low frequency of occurrence beneficial ecosystem processes or services could result in their loss. Given the uncertainty about the connections between ecological function and the delivery of beneficial ecosystem processes, conservation policy and management must consider an ecologically coherent MPA network to be a minimum spatial requirement to secure the future delivery of ecosystem services. 相似文献
17.
Past changes in the Arctic Ocean and its marginal seas have been profound, even during the last 10,000 years. Understanding these changes, such as those occurring during the transition from glacial to interglacial climates, are important for research on modern processes, because this knowledge provides a framework and unique perspective in which to view the modern physical and biological processes. This paper discusses our current understanding of past environmental change and processes relative to those currently in progress. Special emphasis is placed on the most recent transition from a glacial state to the modern interglacial conditions. 相似文献
18.
Photochemical activity in waters of the Great Barrier Reef was investigated through studies on the vertical, horizontal and temporal distribution of hydrogen peroxide and factors influencing its generation and decay processes. Surface hydrogen peroxide concentrations varied from 15 to 110 nM and generally decreased with depth, though a number of anomalies were detected. Photochemical activity decreased with increasing distance from the coast reflecting the positive influence of terrestrial inputs to the hydrogen peroxide generation and decay processes. Increases in photochemical activity were observed in the proximity of coral reefs. Hydrogen peroxide concentrations in the region were influenced by wind-induced mixing processes, atmospheric inputs, anthropogenic activity and seasonal light regimes. 相似文献
19.
Temporal and spatial variations of the back-silting strength in the north passage channel of Changjiang Estuary are investigated using the empirical orthogonal function (EOF) method, with the aim to determine the imposed processes and time-scales. Data on back-silting quantity in every dredging unit of the channel have been collected since March 2000, predominantly once 15 d. The EOF analysis of the back-silting strength reveals two significant modes, which totally explain 58.33% of the overall variance, and the corresponding processes and time-scales. The first EOF mode shows a clear annual cycle which is determined by the riverine water and sediment discharge from the upstream. The second EOF mode reveals a close relation between the back-silting strength and project activities. Because the processes are greatly interrelated in this study case, the other EOF modes accounting for 41.67% of the total variance do not show clear processes and time-scales. 相似文献
20.
环境磁学某些研究进展评述 总被引：21，自引：2，他引：19
环境磁学是应用岩石磁学和矿物磁学技术去恢复环境过程、重塑环境演化历史的一门边缘科学。沉积环境中磁性矿物的形成、搬运、沉积和演化受气候变化和环境过程的控制,因此,岩石和矿物磁学性质可作为环境变化和气候过程的代用指标。环境磁学能为全球环境变化、气候过程研究提供有价值的资料。鉴于环境磁学方法在古环境和古气候研究中的重要作用。本文对当前黄土、湖泊沉积物和海洋喾物环境磁学研究的一些进展作简要评述。 相似文献