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1.
海洋生态系统服务作为一个新兴的研究领域,目前仍未形成统一的分类和评估体系,厘清海洋生态系统服务演变趋势,对海洋可持续管理具有重要意义。本研究从分类、内涵、价值评估和管理应用4个方面揭示国内外海洋生态系统服务研究历程,分析其研究前沿与趋势。结果表明,海洋生态系统服务研究热点起初以中小尺度范围典型生态系统的海洋生物多样性保护为主,而后关注海洋生态过程与服务表现的动态变化、关联特征与定量关系,再逐步转向海洋生态系统服务综合评估模型的研究,现正朝着生态系统服务制图、海洋国土空间规划、生态系统管理决策制定的方向发展。海洋生态系统服务从早期参照陆域生态系统服务常规范式,发展至今已逐渐建立符合海洋特色的分类体系和评估方法,未来亟需加强的研究方向包括海洋生态系统服务流研究、海洋生态系统内供需关系研究和海洋生态系统间权衡与协同关系研究等。  相似文献   

2.
杨灿  徐文喆  孙军 《海洋科学》2023,47(4):176-183
随着纳米塑料在海洋中的分布越来越广泛,纳米塑料逐渐演变成目前海洋生态系统中面临的严重环境问题之一,引起人们的广泛关注。纳米塑料比微塑料粒径更小,具有更大的比表面积与吸附力,成为海洋中污染物的重要载体之一,影响深远。双壳类具有滤食特殊摄食方式,可通过食物链影响其他营养级生物,是食物链中重要一环。本文主要就纳米塑料的定义与来源、在海洋中的污染现状、对海洋双壳类的生态毒理效应进行阐述。纳米塑料可以通过海洋生物呼吸和进食过程中摄入体内,在吞噬细胞中诱导氧化应激、线粒体损伤和细胞毒性并产生严重的炎症反应。研究表明,在有其他污染物的存在下,纳米塑料的存在,会增加污染物在海洋生物体内的留滞时间,从而加大其毒性。纳米塑料可以通过食物网对海洋生态系统构成威胁。  相似文献   

3.
闽南-台湾浅滩渔场鱼类食物网研究   总被引:52,自引:2,他引:52  
海洋鱼类食物网是海洋生态学基础理论研究之一,从多种海洋鱼类食性类型的综合分析,阐明食物网营养级的能流途径,为改造海洋生态系统,减少食物链的环数而提高水域生产力。因此,深入研究海洋鱼类食物网,对于合理利用海洋渔业资源具有一定的实践意义。近年来,国外在河口红树林群落,以残屑(detritus)为基础的食物网研究已有报道[1];对河口游泳动物食物网也发表过综合论述[2]。  相似文献   

4.
浮游桡足类是海洋初级生产力和高级营养级之间能量传递的重要中介,对自然海区桡足类食物组成的研究是深入了解其在海洋食物网所处生态地位的关键。然而,由于研究方法的局限,目前很难获取桡足类准确的现场摄食信息。本文用分子生物学方法研究了黄河口邻近水域中华哲水蚤的现场食物组成,对现场采集固定的中华哲水蚤样品进行清洗、去除附肢、镜检等处理,研磨匀浆后提取总基因组DNA。基于对以此DNA为模板扩增出的非桡足类核糖体小亚基基因(non-copepod 18SrDNA)序列的分析,本文共检测出属于8个门的中华哲水蚤的潜在食物种类。研究结果表明,PCR的分子生物学技术在桡足类摄食研究中具有强大的效用,同时,诸多潜在食物类群的发现也意味着利用分子生物学方法对桡足类及其它海洋生物现场食物组成进行深入系统研究,将有利于揭示海洋生态系统结构与功能的真实状态,促进海洋生态系统物质循环和能量流动的研究。  相似文献   

5.
紫外线B对海洋生态系统的影响   总被引:1,自引:0,他引:1  
本文根据国内外的相关研究资料,讨论了紫外线辐射(主要是紫外线B)对海洋生态系统中各个层次的海洋生物(包括浮游植物、细菌、底栖藻类、微型和小型动物以及养殖经济生物等)的影响及其对海洋环境中的污染物的效应,结果表明紫外线辐射不但对各类海洋生物有比较明显的直接作用,并且通过生态关系进一步影响到整个海洋生态系统的结构,对海洋生态系统造成威胁.  相似文献   

6.
海洋微型底栖生物调查方法与操作规程   总被引:1,自引:1,他引:0       下载免费PDF全文
海洋微型底栖生物包括底栖细菌、底栖微藻及底栖原生动物等单细胞原核和真核生物,是底栖微食物网中能量传递的基础和关键环节,在海洋生物地球化学循环过程中起着重要作用.然而我国现有的<海洋调查规范>国家标准中有关底栖生物的研究仅涉及利用网筛分选的大型和小型底栖动物,缺少微型底栖生物调查的方法与规程,严重制约了对海洋整体食物网能...  相似文献   

7.
我国的海洋生物多样性及其保护   总被引:20,自引:0,他引:20  
本文综述了我国海洋生态系统多样性、海洋物种多样性及其利用以及海洋生物遗传多样性的现状,指出过度捕捞、生境丧失、环境污染、生态入侵是威胁我国海洋生物多样性的主要原因。文本还阐述了我国在海洋生物多样性保护、海洋生态环境监测、海洋自然保护区建设及管理上所取得的成就,以及在海洋生物多样性可持续利用方面所取得的进展。  相似文献   

8.
随着大规模海洋资源与空间开发利用的兴起,海洋生态系统承受的压力愈加增大,海洋环境污染、海洋生物多样性明显下降等问题严重损害海洋生态功能。海洋保护区成为我们保护海洋的最后一道防线,加强海洋保护区建设已被公认为是保护海洋生物多样性和防止海洋生态环境恶化的重要途径。文章通过对北海区国家级海洋保护区的调研研究,阐述了北海区国家级海洋保护区发展现状,分析了目前存在的问题,并提出今后北海区国家级海洋保护区的发展对策。  相似文献   

9.
海洋是生命的摇篮,海洋生态环境关系着我们的未来发展和福祉,关系着人类的前途和命运.当前,海洋生态系统面临气候变化加剧、海洋污染持续、局部海洋生态退化、海洋生物资源衰减、珍稀物种消失等诸多挑战.这些问题警示我们,部分海域海洋生态的保护和修复已经到了刻不容缓的地步."十三五"规划期间,我国大力开展海洋生态保护与修复工作,实...  相似文献   

10.
海洋生物多样性是海洋生态系统的重要组成部分,了解海洋生物多样性的形成演化过程不仅是生命科学的本质问题,而且对海洋生物资源的保护和开发利用具有重要的指导意义。目前海洋生物多样性的形成演化机制尚不明确,而性状多样性的起源和适应性演化为回答海洋生物多样性的内源性机制提供了重要突破口。本文从演化发育生物学的角度综述了海洋动物适应性性状、其研究方法和新兴模式生物的研究进展,重点阐述了印太交汇区的海洋动物适应性演化研究进展,探讨了该区域生物多样中心形成的驱动力,并就未来海洋生物多样性与适应性演化研究提出了建议。  相似文献   

11.
In order to assess the impact of deep-sea mining on the in situ benthic life, we measured the microbial standing stock and concentration of organic nutrients in the deep-sea sediments of the Central Indian Ocean Basin in the Indian pioneer area. Sediments were collected using box core and grab samples during September 1996. The total bacterial numbers ranged from 10 10 -10 11 cells per g -1 dry weight sediment. There was a marginal decrease in the number of bacteria from surface to 30 cm depth, though the subsurface section registered a higher number than did the surface. The highest numbers were encountered at depths of 4-8 cm. The retrievable number of bacteria were two orders less in comparison with the direct total counts of bacteria. An almost homogeneous distribution of bacteria, total organic carbon, living biomass, and lipids throughout the depth of cores indicates active microbial and benthic processes in the deep sea sediments. On the other hand, a uniform distribution of total counts of bacteria, carbohydrates, and total organic carbon in all the cores indicates their stable nature and suggests that they can serve as useful parameters for long-term monitoring of the area after the benthic disturbance. Further studies on temporal variability in this region would not only verify the observed norms of distribution of these variables but would also help to understand restabilization processes after the simulated benthic disturbance.  相似文献   

12.
The interdependence between the seismo-acoustic properties of a marine sediment and its geotechnical/physical parameters has been known for many years, and it has been postulated that this should allow the extraction of geotechnical information from seismic data. Though in the literature many correlations have been published for the surficial layer, there is a lack of information for greater sediment depths. In this article, a desktop study on a synthetic seafloor model illustrates how the application of published near-surface prediction equations to subsurface sediments (up to several tens of meters burial depth) can lead to spurious predictions. To test this further, acoustic and geotechnical properties were measured on a number of sediment core samples, some of which were subjected to loading in acoustically-equipped consolidation cells (oedometers) to simulate greater burial depth conditions. For low effective pressures (representing small burial depths extending to around 10 meters subsurface), the general applicability of established relationships was confirmed: the prediction of porosity, bulk density, and mean grain size from acoustic velocity and impedance appears generally possible for the investigated sedimentary environments. As effective pressure increases through, the observed relationships deviate more and more from the established ones for the near-surface area. For the samples tested in this study, in some instances increasing pressure even resulted in decreasing velocities. There are several possible explanations for this abnormal behavior, including the presence of gas, overconsolidation, or bimodal grain size distribution. The results indicate that an appropriate depth correction must be introduced into the published prediction equations in order to obtain reliable estimates of physical sediment properties for greater subsurface depths.  相似文献   

13.
An acoustic inversion method using a wide-band signal and two near field receivers is proposed and applied to multiple layered seabed models including a manganese sediment. The inversion problem can be formulated into a probabilistic model comprised of signals, a forward model, and additive noise. The forward model simulates wide-band signals, such as chirp signals, and is chosen to be the source-waveletconvolution plane wave modeling method. The wavelet matching technique, using weighted least-squares fitting, estimates the sediment sound-speed and thickness on which determination of the possible numerical ranges for a priori uniform distribution is based. The genetic algorithm is applied to a global optimization problem to find a maximum a posteriori solution for determined a priori search space. Here the object function is defined by an L 2 norm of the difference between measured and modeled signals. Not only the marginal pdf but also its statistics are calculated by numerical evaluation of integrals using the samples selected during importance sampling process of the genetic algorithm.  相似文献   

14.
海上大直径钢管桩打桩过程中,桩周土体受到强烈扰动而发生强度弱化,掌握桩周土体强度弱化规律对于准确预测打桩过程、保证工程安全具有重要意义。为研究土体强度弱化规律,开展了环剪试验模拟打桩对桩周土体的扰动,测试土体强度随剪切速率的变化规律,建立了描述土体强度弱化规律的拟合公式,引入到打桩分析软件中。研究结果表明:土体的强度折减程度不仅与土体本身的性质有关还受到土体的埋深和剪切速率的影响,埋深越深土体强度折减程度越低,剪切速率越高土体强度折减越高,在打桩分析中可采用这里推荐的线性折减方法来模拟不同深度处土体强度的折减规律。  相似文献   

15.
Specific properties of the interannual sea level variations and annual tides in the Northwestern Pacific were studied. Several tide stations were monitored. The monthly mean sea level for the year of 1995 was analyzed at each tide station. A seismic event in 1995, some tectonic activity around the subject area, and the Kuroshio (the oceanic western boundary current) may possibly contaminate results which would have occurred from the astronomical annual tide alone.  相似文献   

16.
The effect of different fixation and storage protocols on the flow cytometric (FCM) simultaneous analysis of bacterioplankton and phytoplankton in coastal seawater samples (Mediterranean coastal lagoons) was investigated. FCM measurements (cell number, fluorescence and scatter characteristics) were obtained through DAPI staining. Three fixatives [glutaraldehyde (GA), formaldehyde (FA) and paraformaldehyde (PFA)] and two storage (3 months duration) methods (5 °C and −196 °C) were tested. Two dominant populations were detected in studied samples: bacteria and eukaryotic picophytoplankton. Adding fixatives (2% final concentration) appears necessary to obtain FCM exhaustive counts of all the bacteria and phytoplanktonic cells. This was related to the permeation effect of fixatives which allowed a better DAPI staining of the cells. Maximum fluorescence, i.e. optimal staining of the cells was obtained with FA or PFA, and significant lower fluorescences with GA. Fixed samples stored at 5 °C induced rapid cell loss. Only storage in liquid nitrogen of samples fixed with FA or PFA, allows mid-term (≥4 months) preservation of bacteria or picophytoplankton cell numbers, and limited evolution of DAPI-induced fluorescence and scatter characteristics.  相似文献   

17.
18.
《海洋学报(英文版)》2014,(9):F0003-F0003
<正>Acta Oceanologica Sinica(AOS)is a comprehensive academic journal edited by the Editorial Committee of Acta Oceanologica Sinica and is designed to provide a forum for important research papers of the marine scientific community which reflect the information on a worldwide basis.The journal publishes scholarly papers on marine science and technology,including physics,chemistry,biology,  相似文献   

19.
20.
Oedometer tests have been carried out on 70 undisturbed surficial clays (at approximately 250 mm below the mudline), mostly collected by free-fall corers from sites widely scattered throughout the deep-sea North Atlantic. Acoustic measurements were also made, initially on contiguous samples and ultimately on the same sample using a geophysically instrumented oedometer which also collected electrical resistivity data. Apart from those quiescent areas below the carbonate compensation depth, such as north of the West Indies where very fine clays exist, most of the samples are silty clays whose geotechnical-geophysical properties are dependent on the type of clay minerals present (and their ability to take in moisture), the sand-size fraction, and the quantity of carbonate present. Thus the pure clays have high compressibilities which decrease on the addition of coarse particles, while the converse is true for the acoustic parameters, these increasing with the sand fraction. Using the notion of the intrinsic compression line for all samples, and comparison to it of the measured compression curves, it is clear that, contrary to some previously held ideas, most deep-sea clays are normally consolidated; the addition of carbonate has the effect of creating an open, stronger sediment skeleton. Interestingly, where information is available, the variation with depth of a sample's acoustic velocity follows the void ratio pressure relationship of the compression curve. This allows the construction of an in-situ sediment compression curve using the in-situ geophysical observations.  相似文献   

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