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1.
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  
池源  石洪华  郭振  丁德文 《海洋学报》2015,37(12):93-105
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   

2.
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   

3.
This article is a brief and selective introduction to the literature and concepts concerning the fate and recycling of carbon compounds in the marine environment. It provides a framework for the other papers in the session and emphasises the areas of ignorance and the implications to be drawn from them.The fate of carbon compounds in oceanic water columns and sediments is reviewed in terms of regions and processes. Particular attention is given to certain regions — surface film and associated zone, the water column and the upper layer of the bottom sediments — and processes — microbial activity, association of organic materials and minerals and the formation and diagenesis of particulate organic matter.Most of the organic matter in the ocean is rapidly recycled but the processes, rates and fluxes are poorly understood. Major areas of ignorance include the half-lives of individual compounds and of classes of compounds and the role of microorganisms, both in the water column and in the bottom sediments. Measurements and experiments need to be conducted in the oceans and in the laboratory. Chemical and biochemical changes in the short and long term require recognition if the residual organic matter of sediments is to be interpreted in terms of past oceanic conditions.  相似文献   

4.
The Gulf of California is unique because of its geographical location and conformation. It hosts diverse ecosystems and important fisheries that support industry and provide livelihood to coastal settlements. It is also the site of interests and problems, and an intense interaction among managers, producers, and conservationists. In this report, we scrutinize the abiotic (hydrography, climate, ocean circulation, and chemistry) and biotic (phyto- and zooplankton, fish, invertebrates, marine mammals, birds, and turtles) components of the marine ecosystem, and some particular aspects of climate variability, endemisms, harmful algal blooms, oxygen minimum layer, and pollution. We also review the current conditions and conflicts around the main fisheries (shrimp, small and large pelagic fishes, squid, artisanal and sportfishing), the most important human activity in the Gulf of California. We cover some aspects of management and conservation of fisheries, especially the claimed overexploitation of fish resources and the ecosystems, and review proposals for creating networks of marine protected areas. We conclude by identifying main needs for information and research, particularly the integration of data bases, the implementation of models and paleoreconstructions, establishment of monitoring programs, and the evaluation of fishing impacts and management actions.  相似文献   

5.
In the 21st century, the climate of expanding megacities and urbanized areas is increasingly forming and changing under the influence of the growing power consumption of the urban economy. To understand the urban climate dynamic and estimate the energy needs of cities in the 21st century, it is necessary to consider not only global and regional climatic factors, but also the presence of feedback between temperature and energy consumption in urbanized areas. This feedback can be both negative and positive, and their significance depends essentially on the climate and landform of the region, system of electricity and heat supply of a city, and some other factors. This article describes the main factors of formation and development of temperature and energy-consumption feedback within urbanized areas in cold and warm seasons when indoor heating or air conditioning is being used. The role of advection in strengthening and weakening of this feedback is studied. The estimates of the parameter and coefficient of feedback strengthening with the influence of anthropogenic heat fluxes and advection on the urban air temperature are presented.  相似文献   

6.
The coastal and marine environments and resources of the Red Sea and Gulf of Aden are globally significant and generally in a healthy state. Current regional issues include localized destruction of coral reefs, seagrass and mangroves; declines in some fisheries; exploitation of some endangered species; pollution from the development and transport of petroleum; and disposal of industrial and municipal wastes. The underlying causes of these issues are the natural vulnerability of the Red Sea due to its semi-enclosed nature; economic reliance on the petroleum industry; significant navigation risks; a rapidly increasing coastal population and associated developments; lack of fisheries information, surveillance and management; poor coastal zone planning; and limited technical expertise. Strategic actions addressing these issues will need to be implemented regionally and focus on coastal zone management that integrates environmental planning, environmental assessment and review; training and institutional development; public awareness and participation; information gathering especially fisheries statistics; reducing navigation risks; and the development of resource management and conservation strategies.  相似文献   

7.
原始影像管理及质量分析系统的设计与实现   总被引:1,自引:1,他引:0  
为了适应摄影测量与遥感技术的快速发展,满足测绘生产的需求现状,针对原始影像的管理与质量分析进行了深入的研究与探讨,并在现有的研究成果和设备的基础上,设计和实现了一套适应于作业部门需求的原始影像管理及质量分析系统。此系统不仅面向测绘生产者提供数据,而且也面向用户提供影像的初级产品———附有内外方位元素的原始影像,为实现原始影像的快速分发和共享提供了良好的服务平台。  相似文献   

8.
Underwater robot positioning and navigation achieve autonomous underwater robot movement based on the premise that positioning obtains the coordinates of the relative position of the underwater robot using a sensor, and navigation yields a known location to the destination path planning. Due to the location of an underwater robot and the complex and changing environment in which it operates, it is difficult to achieve precise positioning using the traditional positioning method. This paper systematically analyzes and summarizes several typical localization and navigation methods of underwater robots, such as multisensor information fusion technology, underwater acoustic localization and navigation methods, GPS buoy, underwater vision, SLAM and coordinate localization and navigation of multiple underwater robots. Multisensory information fusion technology integrates the advantages of the above methods, enhances the system stability and robustness, overcomes the disadvantages of traditional positioning and navigation, and enables the autonomous navigation and positioning of underwater robots. Underwater acoustics enable flexible and convenient positioning, whereas GPS can achieve high-precision and high-positioning navigation information, and visual positioning effectively overcomes the problem of error accumulation. Multirobot cooperative positioning resolves the problem of positioning failure caused by the collapse of a single system and completes complex tasks that cannot be completed by a single robot, thus enhancing the stability and robustness of the system. This paper systematically describes the realization of these methods, presents an actual analysis of their respective advantages and problems, and discusses the development of the field of research prospects and application prospects.  相似文献   

9.
海岸线是海洋与陆地的分界线,海岸线的准确确定对于海岸带空间资源的使用与管理具有重要意义。针对现有的海岸线遥感提取方法存在的技术缺陷,提出从构建海岸线遥感分类体系、改进海岸线遥感推算方法、建立可操作性强的海岸线遥感提取与推算技术体系方面,系统开展海岸线时空动态变化遥感监测的关键技术与应用研究,形成完整可靠的海岸线遥感推算、岸线岸滩动态变化遥感监测技术体系并开展业务化应用,可为海岸带空间资源的合理开发利用提供基础数据支撑和决策分析依据。  相似文献   

10.
On the basis of processing and analysis of the results of many-year observations, we study the process of formation of dome-shaped isosurfaces of hydrological and hydrochemical characteristics for all depths in the Black Sea. We estimate the roles of the intensities of sources and sinks of heat and dissolved substances and the general picture of water circulation, vertical exchange, meso- and small-scale anticyclonic vorticity, and mud and geothermal flows to the preservation of the dome-shaped form of the isosurfaces of these characteristics. Translated by Peter V. Malyshev and Dmitry V. Malyshev.  相似文献   

11.
广东省的湿地:功能、价值、利用和湿地丧失的缓解措施   总被引:3,自引:0,他引:3  
广东的湿地生态系统包括基塘系统、红树林、湿生植被和水生植被等4种生态系统,是特别而有经济价值的植被类型,这些湿地类型分别在支持生物地化循环、保堤护田护村、调节气候、净化环境、生物多样性保育、提供能源、提供生物学科学教育基地和生态旅游地、生产多样化的社会经济原料和产品等方面有着独特而重要的作用。但随着社会的发展.其面积在减少,质量不断下降。结构破坏直接导致了功能的下降和丧失。自1950年起,广东省在其湿地的保护和管理方面陆续实施了统一规划管理、设立自然保护区、开发湿地生产模式、防治湿地污染、保护湿地环境、建设人工湿地、恢复湿地系统、建立湿地信息系统等一系列举措,并取得了一定的收效,但效果仍不理想。要从根本上解决广东湿地的保护和利用问题,一方面要在恢复生态学的指导下深化退化湿地的恢复研究,按照湿地生态系统在空间尺度上的条带分布规律和时间尺度上的演替规律。因地制宜、因时制宜地进行湿地恢复研究;另一方面要进一步加强科研工作者、政府以及民众三者在湿地保护和合理利用方面的合作,建立专门机构,通过法律和行政手段进行统一规划、管理,同时对湿地保育研究、教育给予政策上的倾斜、支持。  相似文献   

12.
为科学合理评价区域海洋科技发展水平,进一步促进区域海洋经济增长,文章以东部海洋经济圈为例,采用主成分分析方法构建海洋科技发展水平综合指标,采用多元线性回归模型分析海洋科技发展等因素与海洋经济增长之间的关系,并提出建议。研究结果表明:海洋科技发展水平综合指标包括海洋科技支撑、海洋科技成果转化和海洋科技投入3个主要素及其11个指标,2006—2015年东部海洋经济圈各地海洋科技发展水平整体处于上升趋势,且差距较小;除政府支持力度外,海洋科技发展水平、海洋第三产业发展水平和工业污染程度等变量均与海洋生产总值存在显著相关关系,其中海洋科技发展水平为正相关;未来应促进海洋科技成果转化、减少区域壁垒制约以及加强海洋生态环境保护和治理。  相似文献   

13.
全球气候变暖已是不争的事实,其导致的极端气候事件增多、增强已成为全球性趋势。近年来全球多个区域存在旱涝并存、旱涝频发的趋势。研究表明,长期旱涝频发的主要原因是全球气温升高致使水循环在时间尺度上产生更强的非均匀性以及人为排放气溶胶粒子增多,短期旱涝急转的主要原因是大气环流形势、暖湿气流输送异常的耦合作用。现阶段对于极端降水和干旱事件同步频发的观测、诊断和模拟较少,不同气候地理条件下两者之间的关系及引起区域降水强度变化的关键性因子等方面亟需深入研究。  相似文献   

14.
褐菖鲉仔、稚鱼生长特性及其关键变态期的研究   总被引:4,自引:2,他引:4  
根据1991~1994年间褐菖YouSebastiscus marmoratus人工苗种培育中仔、稚鱼生物学测定资料及其关键变态期出现时间、特征等资料,研究了日龄与褐菖You仔、稚鱼生长参数间的相互关系,分析了褐菖You仔、稚鱼阶段的关键变态期的出现规律及其生长参数间的关系,探讨了褐褐菖You仔、稚鱼关键变态期的发生机理及其应对措施。  相似文献   

15.
本文根据我国台湾海洋工作者的调查分析资料,对台湾近海的温、盐垂直分布及t-S图解特征进行分析,按其相似性特点进行归类和分型,并探讨它们的特点和异同之处。主要结果如下:1.冬、夏季台湾近海的温、盐垂直分布类型有5种,t-S图解类型为9种。2.冬季台湾近海的水温垂直分布存在着一层、二层、三层结构,夏季多为三层结构;冬、夏季的盐度垂直分布为二层和三层结构。3.台湾西南、南和东北近海,t-S图解类型复杂,出现多种类型交错。4.夏季台湾南端的猫鼻头、鹅銮鼻沿岸附近,其温、盐垂直分布皆出现上均匀层,此现象实属少见。  相似文献   

16.
In order to clarify the distribution and variation of silt and fluid mud in the Waiganmen shallow section of the 50000-ton intake channel of the Xiangshan Port, and to understand the influence of the channel excavation on the surrounding flow conditions and the strength of the backsilting, especially the impact of typhoon on the sudden silting of the channel, so as to demonstrate the feasibility and stability of the channel excavation. The fluid mud,hydraulic, sediment and topographic measurements were carried out in the study area, and the thickness of the fluid mud layers, tidal current, sediment and topographic data were obtained. Dual-frequency sounder, gamma-ray densitometer and SILAS navigational fluid mud measurement system were used to monitor the fluid mud, and the results were compared and verified. The adaptability and accuracy of the three methods were analyzed. The SILAS navigational continuous density measurement system and gamma-ray fixed-point fluid mud measurement are used to detect the density, thickness and variation of the fluid mud accurately. Based on the hydrological observation data,the process of erosion and deposition in excavation channel and its influence mechanism are analyzed, and the distribution characteristics and evolution law of siltation in engineering area are given in the form of empirical formula. The research shows that the super typhoon can produce large siltation, which results in sudden siltation of the channel. The tidal current is the main dynamic factor of the change of erosion and siltation of the excavation trench. Under the influence of reciprocating tidal current and excavation topography, the trial excavation trench is silted on the whole. There is fluid mud in the monitoring area of the trench, and the distribution of fluid mud is different in space. The thickness of the fluid mud at the bottom of the trench is generally larger than that outside the trench and the slope of the trench, and the siltation of the trench tends to be slow. The research results can provide scientific evaluation for channel excavation and maintenance, and support for the implementation of the project.  相似文献   

17.
相建海 《海洋与湖沼》2020,51(4):673-683
著名生物学家童第周、曾呈奎、张玺奠基的中国科学院海洋研究所建所70年来,面向国际学科前沿、国家重大需求和国民经济主战场;刘瑞玉、吴尚懃、张福绥、郑守义为代表的科学家和一批批优秀学科带头人努力攀登,攻坚克难,前仆后继,薪火相传,为我国海洋生物学学科的系统、全面发展做出了重要建树和奠基性贡献,夯实了海洋科学技术发展的根基。近30多年,可为海洋生产力及其可持续性提供解决方案的海洋生物技术受到国内外普遍重视,海洋研究所为国家海洋生物高技术发展战略出谋划策,并在关键技术突破上发力,引领了海洋生物技术的创新发展。在实现产业化,推动蓝色生物产业的征途上,海洋研究所为世界最大的海洋增养殖产业发展壮大做出突出贡献,直接催生了海藻、贝类和对虾三次养殖浪潮的兴起,带动了基础性、战略性海水增养殖种业发展;此外,海洋研究所在海洋药物、海洋生物制品的研究与开发以及着力挖掘和提升海洋生态系统服务功能和价值上,成果斐然,有力支撑了蓝色生物新型产业的发展。新近,海洋研究所牵头筹建的中国科学院海洋大科学研究中心必将为建设海洋强国,铸造蓝色辉煌注入强劲活力。  相似文献   

18.
莺歌海盆地新构造运动与超压体系喷溢油气成藏作用   总被引:7,自引:0,他引:7  
莺歌海盆地是在岩石圈伸展减薄和红河断裂带南段的右旋扭动联合作用下形成的一个以伸展为主的转换—伸展盆地。受该应力场作用,盆地新构造运动活跃,主要表现包括中新统末、上新统与第四纪之间及层系内部的不整合,盆地的沉降,沉积中心的迁移,断裂活动,底辟带的发育与分布,泥火山和地震等。新构造运动不但控制了盆地的形成演化、沉降—沉积中心的迁移和底辟构造带发育以及它们的雁行排列特征,同时还控制了盆地油气的成藏和分布。莺歌海盆地是一个强超压盆地,新构造时期断裂的多期活动及其控制的多期底辟活动不但形成超压体系(包括油气)快速垂向运移的通道,同时决定了莺歌海超压盆地油气田的快速幕式充注成藏规律。成熟的烃类以溶解状态储存在超压体系中,当超压体系孔隙流体压力大于封闭盖层破坏压力时封闭盖层就产生水压破裂,超压体系便沿着活动断裂和底辟带等通道发生喷溢活动,油气向上或侧向往过渡带和常压带运移聚集成藏,随着压力的下降,断裂重新闭合形成新的封闭层。这一喷溢过程以幕式活动形式周而复始,在超压盆地的过渡带和常压带中形成大的油气藏。  相似文献   

19.
提升海上应急搜救能力对保障人民生命安全、维护国家海洋权益、彰显大国责任和担当具有积极作用和深远意义。发达国家海上搜救体系的先进性主要体现在搜救力量专业化、应急响应快捷化、组织协调高效化、搜救业务程序化等方面。文中对美国、英国、澳大利亚、日本4个国家的海上搜救组织构成、搜救力量水平、搜救工作模式等进行了分析,与我国海上搜救体系和机制进行了对比,并从优化搜救组织模式、完善搜救运行机制、健全搜救力量等方面给出了发展我国海上搜救体系的建议。  相似文献   

20.
对兰蛤的主要营养成分 ,以及氨基酸、脂肪酸、无机元素等的组成进行了研究 ,并同贻贝、蛤蜊、虾夷扇贝、牡蛎进行了比较分析。研究结果表明 ,兰蛤的蛋白质含量仅低于虾夷扇贝 ,其粗脂肪的含量居中 ,碳水化合物的含量最低 ,无机元素的含量最高。兰蛤的氨基酸组成非常全面 ,必需氨基酸总量高于牡蛎的 ,丙氨酸含量居于 5种贝类之首。兰蛤的 EPA和 DHA含量之和明显高于其它 4种贝类。兰蛤中还含有丰富的无机元素 ,Fe、Mn的含量均高于其它 4种贝类 ,其它无机元素的含量也较高  相似文献   

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