波浪计算可视化的研究

文章讨论了波浪场可视化实现过程中的一些关键的算法。文中针对表示波浪面的数据集的特性,采用了一种简单的节点法矢量算法。绘制结果表明,用这种简单算法取代二维和三维的数据场节点法矢量的常用算法,能够保持波浪场三维图形的光照效果。利用层次模型算法进行波浪的动态演示,比较了相同面积的波浪场在不同网格密度情况下图形的显示质量,提出波浪场图形质量有与特征波长相匹配的最佳经验网格密度。     

Acoustic Observation of the Time Dependence of the Roughness of Sandy Seafloors

A statistical model for the time evolution of seafloor roughness due to biological activity is applied to photographic and acoustic data. In this model, the function describing small scale seafloor topography obeys a time-evolution equation with a random forcing term that creates roughness and a diffusion term that degrades roughness. When compared to acoustic data from the 1999 and 2004 Sediment Acoustics Experiments (SAX99 and SAX04), the model yields diffusivities in the range from 3.5$,times {hbox {10}} ^{-11}$ to 2.5 $,times {hbox {10}} ^{-10}~{hbox {m}}^{2} {hbox {s}} ^{-1}$ (from 10 to 80 cm$^{2} {hbox {yr}}^{-1}$), with the larger values occurring at sites where bottom-feeding fish were active. While the experimental results lend support to the model, a more focused experimental and simulation effort is required to test several assumptions intrinsic to the model.      

Modelling of the Sea of Azov ecosystem

The method of mathematical model self-organization is applied to handle observations of the hydrological, chemical and biological parameters of the Sea of Azov, conducted from 1926 through to 1985, in order to identify model equations of the latter's ecosystem. A set of 43 evolutionary equations have been employed to generate a picture of the ecosystem parameters' continuous variability and to identify relationships between them. Model calculations of the total catch of freshwater fishes, primary productivity, zoobenthos, phytoplankton, and other characteristics have demonstrated their being in good agreement with the observations conducted from 1950 to 1985. A prediction of the ecosystem parameters' evolution for the period from 1985 to 1995 has been made. Translated by Vladimir A. Puchkin.     

非法占用海域行为的刑法规制探析

因陆地资源逐步紧缺,人类活动向海洋进一步延伸,我国对海洋资源的认识程度和利用能力皆有显著提高,随之而来的便是部分企业和个人对海洋资源的无节制使用及开发,非法围海、占海甚至填海,致使海洋生态环境恶化,地方可持续发展存在障碍,国家海洋经济遭受损失。依据我国现有法律法规,加大对非法占有海域行为进行管控确有成效。然因在实践过程中存在政府越权审批、巨额利益驱使、惩戒力度不够等因素,使得非法占用海域现象屡禁不止,且非法占用行为发生后恢复海域原状之目的难以有效实现。为保障海洋经济、文化永续发展,应用最严格和最严密的法治保护国家海岸线和海洋生态环境安全;使行政执法与刑事规制相衔接,建立信息互联共享机制;成立专项组整治非法占用海域行为,形成示范效应,为日后打击此类案件积累经验。     

Mechanism of the formation of volcanic chains of French Polynesia

A possible mechanism of the formation of chains of intraplate seamounts and islands alternative to the “hot spot” hypothesis is considered. It is related to the appearance of additional stresses in the lithospheric plate when it ascends over a mantle inhomogeneity and descends from it. The magnitude of these stresses (～600 bar) is sufficient for formation of deep fracture zones. In the paper, schemes of formation of volcanic chains are described. The formation of the “faults-volcanoes-volcanic chains” sequence may follow two different ways. The first is controlled by the fracture zones formed along the direction of the plate movement. In this case, feeding channels are localized along the boundary of the rise. If the chain is gradually formed simultaneously with the plate motion, the age of the volcanoes along the chain may change in a more or less regular way. The second type is formed by fractures orthogonal to the movement direction. They may be formed when the plate ascends over a mantle inhomogeneity and/or descends from it. In this case, adjacent volcanoes may have similar ages. A combination of these two variants may also be encountered. The mechanism posed allowed us to explain selected facts referring to the volcanic chains of French Polynesia and may be applied to other regions of the Pacific Ocean.     

Estimates of fishery potentials of the EEZ of India

An attempt has been made to estimate the fishery potentials of the EEZ of India on the basis of data on primary and secondary production. The total column primary production and zooplankton production have been calculated to be 265·9 and 9 million tonnes of carbon per year, respectively. From these values the fishery potential has been estimated as 2·5 million tonnes per year. To this, if we add the estimated demersal fish catch, being 1·2 million tonnes per year, the total potential yield comes to 3·7 million tonnes per year. Since the present average total catch is about 1·6 million tonnes in a year, the fish catch could be doubled.     

Modeling of the propagation of transient waves of moderate steepness

A theoretical approach is applied to predict the propagation and transformation of nonlinear water waves. A semi-analytical solution was derived by applying an eigenfunction expansion method. The solution is applied to analyze the effect of wave frequencies and wave steepness on the propagation of nonlinear waves. The main attention is paid to the wave profile, the wave energy spectrum, and the changes of wave profile and energy spectrum due to the interaction of wave components in a wave train. The results show that for waves of low steepness the nonlinear wave effects and effects associated with the interaction of water waves in a wave train are of secondary importance. For waves of moderate steepness and steep waves the effects associated with the interactions between waves in a wave train are becoming significant and a train of initially sinusoidal waves may drastically change its form within a short distance from its original position. The evolution of wave components has substantial effects on the wave spectrum. A train of initially very narrow-banded waves changes its one-peak spectrum to a multi-peak one in a fairly short period of time. Laboratory experiments were conducted in a wave flume to verify theoretical approaches. The free-surface elevation recorded by a system of wave gauges was compared with the results provided by the semi-analytical solution. Theoretical results are in a fairly good agreement with experimental data. A reasonable agreement between theoretical results and experimental data is observed often even for relatively steep waves.     

Effect of modification of particle size of emulsions of venezuelan crude oil on feeding,survival and growth of marine zooplankton

Variations in the natural particle size spectra following the addition of Venezuelan crude oil in seawater ($\text{? 6 μ}\text{l litre}{}^{\mathrm{?1}}$) were related to the mixing speeds of the emulsion and were independent of the oil concentration. The particle spectrum and feeding behaviour of Meganyctiphanes norvegica and Calanus hyperboreus were both modified. Artificially created oil droplets were suitable in size for ready ingestion by zooplankton. The growth and survival of contaminated Acartia hudsonica were rapidly and significantly reduced. Groups under starvation conditions showed similar decreases to those exposed to oil. During a depuration period, treated copepods exhibited growth rates similar to those of untreated specimens. The input and noxious effects of crude oil are discussed with special reference to particle size distribution and chemosensory feeding behaviour.     

A review of game-theoretic models of fishing

Game theory is a formal tool for analysing strategic interaction between a finite number of agents. The fact that usually more than one entity or agent has property rights to fishery resources, has led to an explosion in the use of game theory and applications thereof to analyse fishery management problems. This review shows that game-theoretic modelling has made significant contributions to our understanding of the problems of fishery resource management. However, many challenges still remain. For instance, models of straddling stocks are yet to be fully developed. In addition, fisheries economists have not yet fully exploited the opportunity provided by computational methods now available, and the ever increasing power of computers, to develop more empirical game-theoretic models for practical fisheries management.     

深海油水主动旋流分离器强制涡流前推段结构对分离性能影响数值模拟

针对深水油气田主动旋流分离器强制涡流前推段锥度对分离性能的影响进行研究,应用RSM(reynolds stress model)湍流模型对主动旋流器内部强旋流场进行数值模拟计算,在强制涡流前推段锥角变化时,合理预测并对比其内部轴向速度、切向速度、离心力以及分离效率的变化。研究表明在一定范围内,前推段锥度的增加可以提高混合液在前推段内的轴向速度和切向速度,进而可以获得更高的分离效率。当锥角达到15°时,可以获得最为理想的分离效果。此外,在不同深水环境下对该主动旋流分离器进行仿真计算表明,不同的环境压力对旋流器分离效率影响很小。     

Evidence of a common understanding of proximate and distal drivers of reef health

Marine management has typically prioritised natural science methodological traditions as an evidence base for decision-making; yet better integration of social science methods are increasingly shown to provide a more comprehensive picture to base management decisions. Specifically, perceptions-based assessments are gaining support, as they can provide efficient and holistic evaluation regarding management issues. This study focuses on coral reefs because they are particularly threatened ecosystems, due to their ecological complexity, socio-economic importance, and the range of environmental drivers that impact them. Research has largely concentrated on assessing proximate threats to coral reefs. Less attention has been given to distal drivers, such as socio-economic and governance factors. A common understanding of threats related to coral reef degradation is critical for integrated management that takes account of peoples’ concerns. This study compares perceptions of drivers of reef health among stakeholders (n = 110) across different sectors and governance levels, in four Caribbean countries. Interview data identified 37 proximate and 136 distal drivers, categorised into 27 themes. Five sub-groups of themes connecting proximate and distal drivers were identified. Perceptions of two of these narratives, relating to ‘fishing and socioeconomic issues’ and ‘reef management and coastal development’, differed among respondents from different countries and sectors respectively. However, the findings highlight a shared perception of many themes, with 18 of the 27 (67%) mentioned by > 25% of respondents. This paper highlights the application of perceptions data for marine management, demonstrating how knowledge of proximate and distal drivers can be applied to identify important issues at different context-specific scales.     

地质储量精细计算方法研究

石油、天然气地质储量是指导油气田勘探、开发,确定投资规模的重要依据。随着高含水期油田开发工作的不断深入,为了解决储采失衡的矛盾,我们提出根据三角网法确定单井控制面积,继而计算单井不同类型砂体地质储量,解决了目前采用的“单井控制面积=区块总面积／区块总井数”和“厚度碾平”算法所产生的误差,使地质储量计算更加合理,从而实现了对沉积单元和具体类型砂体进行地质储量精细计算的要求。．     

Introduction of accumulation-dispersal coefficient of marine organisms

Avoiding the subject for fish accumulation, the traditional view in fish population dynamics has ascribed immigration and emigration of fish to dispersal of fish. The main purpose of this paper is to find a quantity that represents the time rate of accumulation-dispersal of marine organisms, and also has some relation to the horizontal convergence of current velocity of the surrounding water. For this, the accumulation-dispersal coefficient is introduced not in the form of diffusion, but in the same form as the convergence. Since the accumulation-dispersal of organisms is a factor that changes its distribution density, all factors causing the change are first classified to locate the position occupied by the accumulation dispersal. Each factor corresponds to each coefficient appearing in a linearized equation describing the rate of change in the density, averaged over a region or a group. The immigration-emigration coefficient is divided into three coefficients of passage, accumulation dispersal and diffusion velocity. For the organisms ranging in a nearly horizontal layer, the accumulation-dispersal coefficient is shown to equal the area-averaged horizontal convergence of organismal velocity relative to land, which is the sum of the area-averaged horizontal convergences of swimming velocity relative to water and of current velocity. However, the area-averaged convergence of current velocity associated with the accumulation-dispersal coefficient for a region is shown to be somewhat different from the usual one.     

The stages of the development of the basin of the Bransfield Strait

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.     

Analysis of the intensification of tsunami waves near the South Coast of Crimea

We perform the numerical analysis of the intensification of tsunami waves in the course of their propagation from the open part of the Black Sea to the shelf zone. For this purpose, we use a one-dimensional model of nonlinear long waves taking into account the effect of bottom friction. We study four profiles of the bottom corresponding to the south coast of the Crimean Peninsula and establish the predominant role of the bottom pattern and insignificant contribution of nonlinearity to the transformation of waves in the process of their propagation in the direction of the coast. Down to depths of 50 m, all changes in the height of waves are described by the Green law. For the evaluation of vertical run-up of waves, it is important to take into account nonlinear effects. The highest vertical run-ups of waves are observed in the parts of the shelf zone located near Yalta and Alushta. Translated by Peter V. Malyshev and Dmitry V. Malyshev     

Prediction of short-term distributions of load extremes of offshore wind turbines

This paper proposes a new methodology to select an optimal threshold level to be used in the peak over threshold (POT) method for the prediction of short-term distributions of load extremes of offshore wind turbines. Such an optimal threshold level is found based on the estimation of the variance-to-mean ratio for the occurrence of peak values, which characterizes the Poisson assumption. A generalized Pareto distribution is then fitted to the extracted peaks over the optimal threshold level and the distribution parameters are estimated by the method of the maximum spacing estimation. This methodology is applied to estimate the short-term distributions of load extremes of the blade bending moment and the tower base bending moment at the mudline of a monopile-supported 5MW offshore wind turbine as an example. The accuracy of the POT method using the optimal threshold level is shown to be better, in terms of the distribution fitting, than that of the POT methods using empirical threshold levels. The comparisons among the short-term extreme response values predicted by using the POT method with the optimal threshold levels and with the empirical threshold levels and by using direct simulation results further substantiate the validity of the proposed new methodology.     

厦门寨后垃圾填埋场释气影响及其控制

本文是在承担厦门市寨后“垃圾埋场”工程环境影响评价的基础上,对该填埋场的垃圾释气规律作进一步研究。研究结果表明,（１）厦门煤气的普及率较高;（２场营运１１ａ左右,废气产物量及排一达到最大值;（３）于小风条件下,在下风向５０ｍ处,ＣＨ４浓度可达爆炸极１６￣３１％,所产生的恶臭气体Ｈ２Ｓ的影响距离经ＮＨ３大,在下风向５００ｍ下才能达到２级场界标准;（４）严格按卫生填埋的技术标准进行规范操作,确保排气管     

Model of the post-Cenozoic evolution of the cryolithozone of the shelf of the western part of the Laptev Sea

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.     

海底表层底质探测系统测试仪的设计

海底表层底质探测系统是一种新型的声学探测设备,它利用声学信号实时走航式地遥测海底的表层底质。本测试仪用于在试验室条件下对海底表层探测系统性能的测试。由于该测试仪在设计过程中充分考虑到了目前测深仪的情况,所以也可以用于测深仪的性能测试。     

Pilot Census of marine life in the Gulf of Maine: contributions of technology

Recent advances in physical oceanography, sampling and observation tools, and data management methods are sufficient to enable a wide range of organisms in the Gulf of Maine to be quantified and related both to other organisms and to the physical habitat. A pilot Census of marine life in the Gulf of Maine would advance the goals of ecosystem understanding and management in a timely manner. A prerequisite is knowledge of the distribution and abundance of the organisms that inhabit, both permanently and transiently, the Gulf of Maine and adjacent waters, namely those of Georges Bank, Browns Bank, and Slope Sea, including the New England seamounts. Both systematic and synoptic investigations of a spectrum of marine life are needed to supplement current data holdings, which, if extensive with respect to fish and certain marine mammals, are sparse with respect to the larger biogeography of the system. Technology offers the means of collecting and organizing such data. Efficiency in collection argues for dividing the spectrum of marine life into a number of functional groups, whose constituent organisms can be observed or sampled by the same or similar techniques. Five groups are identified: offshore subtidal benthos, intertidal and nearshore subtidal benthos, plankton, fish and squid, and large marine animals and seabirds. Associated tools of observation and sampling are listed and illustrated for two categories: high-frequency scientific echo sounders and underwater video microscopes. Parameters of the physical habitat are listed, and the power of the Gulf of Maine Ocean Observing System to define the physical oceanography is noted. Issues of data management, systems, and uses are described. Some benefits of a pilot census are noted. For the scientific community, these include making available biogeographic data that can support the formulation of data-based hypotheses. Testing these in the Gulf of Maine and adjacent waters may enable new knowledge of the particular ecosystem to be extended to distant ecosystems.