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1.
黄河1964—1976年刁口流路泥沙冲淤及其分布特点 总被引：1，自引：0，他引：1
本文研究了刁口流路行水期间,河道演变全过程的泥沙冲淤变化,叠合沙体的发展演变,计算了各阶段不同深度范围的淤积量,从而总结了泥沙淤积分布的特点,提出了新的资料和认识. 相似文献
2.
为定量研究沿海城市经济高速发展对其海岸类型变迁的影响以及海岸类型变迁历程对经济发展阶段的响应作用,文章基于厦门地区30余年来海岸类型和海洋经济的统计数据,阐明自厦门经济特区成立以来不同海岸类型占比变化与海洋经济总值和产业类型变化的规律及其关联性。厦门海岸类型变迁经历3个阶段:1984—2000年,海岸开发利用处于起步阶段,海岸利用类型为以盐业和渔业为主的粗放型和集约化的低产值类型;2000—2010年,海岸开发利用处于高速发展阶段,海岸利用类型为以大规模填海造地、交通运输和旅游娱乐为主的开发型高产值类型;2010年至今,海岸开发利用处于合理开发与保护并行且以保护为重的恢复阶段,海岸利用类型为生态恢复和软质护岸等近自然类型。厦门海岸类型变迁与经济发展密切相关,人类日益增长的物质文明和生态文明需求对城市海岸类型变迁的响应特征十分显著。从粗放型第一产业,到发展型第二产业,再到保护型第三产业,经济发展从理念与要求并存到理念超越要求,最终实现理念与要求和谐共存和相融互进的经济发展模式。 相似文献
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随着海洋与海岸带开发利用活动的复杂化和深入化,海岸带地区的资源环境问题逐渐显露出来,经济效益降低,传统单一的海岸带管理模式无法满足海洋开发的需求。国外由此提出了海岸带综合管理的概念,我国与之对应的是陆海统筹发展战略。文章对海岸带综合管理与陆海统筹的发展历程进行梳理,分析其概念内涵及发展变化,并从战略目标、空间范围、功能范围和实施手段4个方面比较了二者内涵的异同。最后,指出海岸带综合管理与陆海统筹后续研究应加强海岸带综合管理典型案例研究,推动海岸带综合管理走向海岸带综合治理,探讨人、陆、海三者耦合的机理和过程,加强陆海统筹的发展路径研究。 相似文献
4.
21世纪是"海洋的世纪",发展海洋事业已成为全世界的一种广泛共识。党的十九大提出了"坚持陆海统筹,加快建设海洋强国"的重大战略部署,海上合作是"一带一路"建设聚焦的重点领域之一。在新的形势下,通过全面总结我国海洋科技进展,系统分析"一带一路"国家海洋科技合作重点领域情况,我国应在已有良好合作的基础上,更进一步推进双边海洋科技合作伙伴关系,建立海洋领域联合研究中心,结合重点方向,积极开展联合科学研究和技术应用,实现技术装备和数据产品的共享,促进海洋经济发展,加强海洋技术的转移转化,开展人员交流培训和合作研究,互学互鉴、互利共赢,提升我国海洋科技的创新力和国际影响力,加快构建海洋命运共同体,为推动人类命运共同体作出积极贡献。 相似文献
5.
海洋生态补偿机制是促进海洋资源科学开发利用与海洋生态环境质量改善、推动海洋经济高质量发展的一项重要环境经济手段。文章结合新时期海洋生态文明领域政策演进的新动向,梳理近年来我国主要沿海省（自治区、直辖市）海洋生态补偿制度实践的进展情况,从系统性视角总结分析国家和地方层面海洋生态补偿政策与法律制度建设的经验和差距。着眼于海洋生态补偿政策体系完善和地方管理机制的改进需求,从统筹协同角度,建议未来从政策协同、多元机制协同、跨部门协同、跨区域协同和信息资源协同等方面,推动建立完善陆海统筹的海洋生态补偿协同治理体系。 相似文献
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7.
不同池塘养殖模式的环境氮磷负荷及其水质特征 总被引：3，自引：0，他引：3
2008年3月至2009年1月研究了广东海丰县东关联安围湿地两种投饵养殖模式——对虾主养(半集约化养殖)和虾蟹混养(半集约化养殖)海水池塘的环境氮磷负荷和养殖水体氮磷含量的周年变化情况,并以不投饵的塭围虾贝混养(粗放式养殖)模式为对照。3种模式中,池塘单位面积环境氮、磷负荷以对虾主养模式最高,分别为36.52 kg/hm2和7.39 kg/hm2;虾蟹混养模式次之,分别为1.49 kg/hm2和0.52kg/hm2;而塭围虾贝混养模式最低,分别为–2.47 kg/hm2和–0.34 kg/hm2。每月1次对3种模式养殖过程中水体的总氮、硝酸氮、亚硝酸氮、氨氮和总磷及磷酸盐含量进行监测,结果表明,与养殖环境氮磷负荷大小相对应,塭围虾贝混养池塘水质最好,虾蟹混养池塘次之,而对虾主养池塘水质最差,这种现象尤其在养殖后期更为明显。 相似文献
8.
海水的氧饱和度与韦斯方程 总被引：2，自引：0，他引：2
1973年 ,联合国教科文组织 (U NESCO)汇同英国国立海洋研究所 (NOI)联合颁布了“国际海洋学用表”第二卷 ,即由国际海洋学用表与标准联合专家小组监督制订 ,由 NOI与 UNESCO,依据韦斯方程编辑出版的海水氧饱和度表。韦斯方程是海水中氧的溶解度与温度和盐度关系的一组方程式 ,它提供了一种计算海水中氧的溶解度的简便而又系统的方法。本文主要介绍了韦斯方程的推导过程、计算方法、数据引用、适用范围及公式精度等技术问题 ,供海洋科技工作者研究、参考 ,以利于进一步提高海水溶解氧的观测技术及计量标准工作的水平 相似文献
9.
Niu Xuexin 《海洋学报(英文版)》1990,9(4):539-546
In this paper,the analysis of the occurrence and the development of typhoon and tropical cyclone is made with the unstable theory of wave. The result indicates that the primary wave is the unstable inertia-gravity wave in the process of the occurrence and the deveJopmant of typhoon and tropical cyclone: The existence of the deep moist layer and the heating by moisture condensation can impel and intensify the unstability of the wave and is favourable for the reduction of the wave energy dispersion, therefore, it is good for the formation and the development of typhoon and tropical cyclone, and also can slow down the wave speed. Besides, the condition that the change of the specific volume of the basic state with pressure is less than that of adiabatic state may also lead to the wave unstability, thus may have certain effect on the occurrence and the development of typhoon and tropical cyclone. 相似文献
10.
《Marine Policy》2014
Limits and barriers to adaptation restrict people’s ability to address the negative impacts of climate change or manage risks in a way that maximises their wellbeing. There is a lack of evidence of this on small-scale fishing communities in developing countries. This study identifies and characterises limits and barriers to adaptation of fishing activities to cyclones and examines interactions between them in two fishing communities in Bangladesh, using household questionnaires, oral history interviews, vulnerability matrices and focus group discussions. The limits include physical characteristics of climate and sea like higher frequency and duration of cyclones, and hidden sandbars. Barriers include technologically poor boats, inaccurate weather forecast, poor radio signal, lack of access to credit, low incomes, underestimation of cyclone occurrence, coercion of fishermen by the boat owners and captains, lack of education, skills and livelihood alternatives, unfavourable credit schemes, lack of enforcement of fishing regulations and maritime laws, and lack of access to fish markets. These local and wider scale factors interact in complex ways and constrain completion of fishing trips, coping with cyclones at sea, safe return of boats from sea, timely responses to cyclones and livelihood diversification. The findings indicate a need for further detailed research into the determinants and implications of such limits and barriers, in order to move towards an improved characterisation of adaptation and to identify most suitable means to overcome the limits and barriers. 相似文献
11.
海岛生态脆弱性的内涵、特征及成因探析 总被引：4，自引：0，他引：4
海岛生态系统拥有明显且独特的脆弱性,对海岛的生态环境和社会经济构成威胁。准确把握和有效控制海岛生态脆弱性是维护海岛生态系统、合理开发利用海岛的根本前提,一套科学、统一且针对性强的概念体系是海岛生态脆弱性研究的基础。参考相关研究,以海岛生态系统的特殊性为基点,以我国海岛为侧重点,通过梳理和分析大量海岛典型案例,提出并探析海岛生态脆弱性的内涵、特征和成因。海岛生态脆弱性是在独特的自身条件和复杂的系统干扰下海岛生态系统表现出的易受损性和难恢复性,具备长期性、分异性和可调控性的特征;特殊的地理位置、有限的规模大小和明显的空间隔离使得海岛生态系统具有明显的海陆二相性、资源短缺性和独立完整性,与不同类型、不同程度的自然扰动和人为干扰相互作用,形成并加剧海岛生态脆弱性。概念体系的建立能够为海岛生态脆弱性的深入分析与合理调控提供切实依据。 相似文献
12.
《Marine Policy》2015
Some of the most important development goals for the countries and territories of the Western and Central Pacific Ocean (WCPO) involve the sustainable management of their fisheries in light of environmental, economic and social uncertainties. The responses of fish populations to variability in the marine environment have implications for decision making processes associated with resource management. There is still considerable uncertainty in estimating the responses of tuna populations to short-to-medium-term variability and longer-term change in the oceanic environment. A workshop was organised to examine how advances in oceanography, fisheries science and fisheries economics could be applied to the tuna fisheries of the WCPO and in doing so identify research priorities to improve understanding relevant to progressing management. Research priorities identified included: (i) improved parameterisation of end to end ecosystem model components, processes and feedbacks through expanded biological observations and incorporation of higher resolution climate models; (ii) development of seasonal and inter-annual forecasting tools enabling management responses to short-term variability in tuna distributions and abundances; (iii) improved understanding of the population dynamics of and the energy transfer efficiencies between food web components; (iv) assessment of the optimal value of access rights and overall fishery value under multiple scenarios of tuna distribution and abundance and influences on decision making by fisheries managers and fleets and (v) development of management strategy evaluation frameworks for utilisation in the implementing and testing of fishery management procedures and to help prioritise research directions and investment. Issues discussed and research priorities identified during the workshop have synergies with other internationally managed fisheries and therefore are applicable to many other fisheries. 相似文献
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14.
Xiaojun Xie Wu Tang Gongcheng Zhang Zhigang Zhao Shuang Song Shixiang Liu Yibo Wang Jia Guo 《海洋学报(英文版)》2023,42(3):123-137
This study involved outcrop, drilling, seismic, gravity, and magnetic data to systematically document the geological records of the subduction process of Proto-South China Sea (PSCS) and establish its evolution model. The results indicate that a series of arc-shaped ophiolite belts and calcalkaline magmatic rocks are developed in northern Borneo, both of which have the characteristics of gradually changing younger from west to east, and are direct signs of subduction and collision of PSCS. At the same time, the subduction of PSCS led to the formation of three accretion zones from the south to the north in Borneo, the Kuching belt, Sibu belt, and Miri belt. The sedimentary formation of northern Borneo is characterized by a three-layer structure, with the oceanic basement at the bottom, overlying the deep-sea flysch deposits of the Rajang–Crocker group, and the molasse sedimentary sequence that is dominated by river-delta and shallow marine facies at the top, recording the whole subduction–collision–orogeny process of PSCS. Further, seismic reflection and tomography also confirmed the subduction and collision of PSCS. Based on the geological records of the subduction and collision of PSCS, combined with the comprehensive analysis of segmented expansion and key tectonic events in the South China Sea, we establish the “gradual” subduction-collision evolution model of PSCS. During the late Eocene to middle Miocene, the Zengmu, Nansha, and Liyue–Palawan blocks were separated by West Baram Line and Balabac Fault, which collided with the Borneo block and Kagayan Ridge successively from the west to the east, forming several foreland basin systems, and PSCS subducted and closed from the west to the east. The subduction and extinction of PSCS controlled the oil and gas distribution pattern of southern South China Sea (SSCS) mainly in three aspects. First, the “gradual” closure process of PSCS led to the continuous development of many large deltas in SSCS. Second, the deltas formed during the subduction–collision of PSCS controlled the development of source rocks in the basins of SSCS. Macroscopically, the distribution and scale of deltas controlled the distribution and scale of source rocks, forming two types of source rocks, namely, coal measures and terrestrial marine facies. Microscopically, the difference of terrestrial higher plants carried by the delta controlled the proportion of macerals of source rocks. Third, the difference of source rocks mainly controlled the distribution pattern of oil and gas in SSCS. Meanwhile, the difference in the scale of source rocks mainly controlled the difference in the amount of oil and gas discoveries, resulting in a huge amount of oil and gas discoveries in the basin of SSCS. Meanwhile, the difference of macerals of source rocks mainly controlled the difference of oil and gas generation, forming the oil and gas distribution pattern of “nearshore oil and far-shore gas”. 相似文献
15.
《Oceanologica Acta》2002,25(5):213-218
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. 相似文献
16.
八放珊瑚广泛分布在近岸浅海到深海,以及热带、温带甚至寒带等高纬度海区,在维持海洋生态系统结构完整性和生物多样性方面发挥了重要作用。受气候变化和人类活动影响,八放珊瑚呈现不断衰退趋势,忽视海洋生态系统原生物种自然禀赋的现象明显,尤其是八放珊瑚可供头足类产卵附着的生态功能尚未引起足够重视。本文综合梳理了八放珊瑚的结构和分类、繁殖特性和生殖方式、影响生态因子和退化原因等研究现状和问题,提出针对性保护和修复八放珊瑚的对策与建议,以期为我国重要生态系统保护和修复重大工程的实施提供基础资料。 相似文献
17.
Sediments of the continental slope are commonly bioturbated by endo- and epibenthic organisms, particularly in and around submarine canyons and channels. This study reviews the architecture and depositional environments associated with canyons and channels on the continental slope, and assesses the key physical and chemical conditions encountered in and around these conduits. Hydrodynamic energy, concentration and quality of organic carbon, dissolved oxygen concentration and sedimentation rate are identified as key controls on the composition of benthic ecosystems in slope environments. Submarine canyons and channels focus a variety of turbid and clear-water currents, all of which serve to increase the concentration of oxygen, labile organic carbon and other nutrients, which tend to elevate the abundance and biodiversity in the seafloor sediments, compared with those of the surrounding slope. Ancient slope channel and canyon systems reflect some of the variation in ichnological assemblages that is seen in modern analogues, although processes of erosion and trace fossil preservation mean that the benthic environment is often incompletely preserved in the ancient record. By integrating current understanding of sedimentology, oceanography, biology and ichnology of slope environments it is possible to provide a first order summary of the inter-relationships between ichnology and depositional environments on the continental slope. The combination of these data has the potential to improve our understanding of changes in deep marine benthic ecosystems through geological time, and to further the use of ichnology in assessing hydrocarbon reservoir presence, quality and performance from bioturbated slope, canyon and channel-levee hydrocarbon reservoirs. 相似文献
18.
海岛资源的可持续发展研究是海洋开发与管理的重要课题。为优化配置海岛资源,促进海岛开发利用和生态环境保护的协调发展,参考相关研究,以海岛生态系统的特殊性为基点,对海岛生态系统脆弱性的概念、内涵和特征进行综述;以辽宁海岛为侧重点,通过梳理和分析大量海岛典型案例,提出了海岛生态系统脆弱性的成因及表现,建立其影响机制框架,并在此基础上,初步探讨了海岛生态系统脆弱性的评价体系和评价方法,最后提出了研究展望。海岛生态系统脆弱性是在一定的自然因素和人为因素背景下,海岛生态系统响应与自然环境相互作用和人类对海岛的开发利用过程中表现出的敏感反应与自恢复能力,是客观存在的、敏感的、难恢复的,具备长期性、差异性和可调控性特征,在不同类型、不同程度的自然扰动与人为干扰作用下,海岛生态系统脆弱性表现也不同,其驱动机制与评价体系的建立能够为后续深入研究提供思路。本研究结果可为海岛生态环境保护提供科学依据,对促进海岛的可持续发展具有现实意义。 相似文献
19.
河口、海岸是陆海相互作用及人类活动最频繁的地区之一,了解和把握海岸地貌的变迁及发育模式对于海岸资源的开发和保护至关重要。模型是对客观事物的概括和抽象,本文对海岸滩地和水下三角洲地形演变的研究总结了4种方法,重点讨论了模型的构建,并根据作者的研究实例给出了模型的具体应用。在剖面模型的应用中通过不同年代剖面的对比分析可了解海岸地貌的动态变化,平面模型则通过等深线的退缩、扩张及形态变化来研究岸滩的动态冲淤及海岸地形的宏观变化,而冲淤速率分布平面图是分析大范围海域冲淤趋势和局部变化的有效手段。测点统计模型是一种静态分析方法,用来建立测量点的高程和坡度与岸滩冲淤的关系。 相似文献
20.
胶州湾滨海湿地的水禽多样性特征及保护 总被引：4，自引：0，他引：4
在利用相对数量法进行水禽种群调查基础上,研究胶州湾滨海湿地水禽区系的构成及多样性特征.研究区共有水禽9目20科140种,区系的地理成分以古北界鸟类占绝对优势,季节型成分以冬候鸟和旅鸟为主,生活型成分以涉禽为主;在不同季节研究区水禽的优势种群不同,夏季鸥科和鹭科为优势种群,春、秋季鴴科、鹬科、鹭科为优势种群,冬季雁鸭类、鸥科为优势种群.与青岛市陆禽、鸣禽、猛禽、攀禽等鸟类相比,胶州湾滨海湿地水禽的多样性指数、均匀度指数最高,说明胶州湾滨海湿地对青岛市鸟类多样性保护非常重要,生境破坏是当前水禽多样性保护面临的主要问题,提出了水禽生境保护的对策. 相似文献