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1.
基于SBM模型的我国海洋渔业生态效率的时空演变   总被引:1,自引:0,他引:1       下载免费PDF全文
随着"海洋强国"建设的深入实施,我国海洋经济实力不断提升,但也出现海洋环境污染和生态破坏等制约海洋产业可持续发展的问题,亟须改善海洋生态环境和提高海洋产业生态效率。文章以海水养殖排污总量作为非期望产出,采用SBM模型、标准差和变异系数,分析2006—2015年我国海洋渔业生态效率的时空演变特征,并对我国沿海地区的海洋渔业生态效率水平进行分类。研究结果表明:2006—2015年我国海洋渔业生态效率整体处于中等水平,且呈波动式下降趋势;沿海各地区的海洋渔业生态效率差异显著,且差异呈不断扩大的趋势;沿海各地区的海洋渔业生态效率水平可分为高效型、中效型和低效型3个类型,其中广东省和江苏省从中效型下降至低效型,主要原因在于其存在生态恢复滞后性。  相似文献   

2.
文章基于非期望产出的超效率SBM模型,测算2007—2016年中国海洋渔业生态效率,运用标准差椭圆刻画其时空分异特征,并引入广义矩估计模型分析其影响因素。研究结果表明:中国海洋渔业生态效率呈现波动上升的趋势,但整体仍处于较低水平,有较大的提升空间;海洋渔业生态效率较高的地区为江苏、广东和山东,生态效率中等的地区为浙江,生态效率低的地区为辽宁和福建,生态效率无效的地区为河北、广西和海南;海洋渔业生态效率空间分布的重心整体向东南方向偏移,且空间格局在南北方向呈扩张状态,在东西方向呈收缩状态;海洋渔业的产业结构、环境规制和科技支撑对海洋渔业生态效率的提升起正向作用,而对外开放程度对海洋渔业生态效率的提升起负向作用。  相似文献   

3.
研究海洋渔业产业结构优化对碳排放的影响,对于促进海洋渔业高质量发展具有重要的现实意义。文章基于2008—2017年我国沿海9省(自治区)的面板数据,运用数据包络方法计算海洋渔业碳排放效率,并采用空间计量模型,探讨海洋渔业产业结构优化对碳排放效率的影响。研究结果表明:我国海洋渔业碳排放效率的地区差异显著,除河北和广西外,其他地区均具有较高的海洋渔业碳排放效率;从空间特征看,海洋渔业产业结构优化水平具有显著的空间集聚性,海洋渔业碳排放效率也存在一定的空间依赖性,碳排放效率的"高-高"集聚特征较为明显;从回归结果看,海洋渔业产业结构优化和海洋渔业经济水平对海洋渔业碳排放效率具有显著的正向影响,这种影响不仅作用于本地区,而且辐射和扩散到邻近地区;渔民收入、渔业科研投入和渔业对外开放水平对海洋渔业碳排放效率存在一定的负面影响。  相似文献   

4.
以碳排放为非期望产出,运用非期望产出的SBM模型和Malmquist生产力指数对中国沿海11个省市区(不含港、澳、台)2006-2014年的海洋经济效率和全要素生产率进行测度,分析表明:(1)中国海洋经济平均效率在研究期内一直处于较低水平,整体上处于下降态势,但在研究期末有所回升;空间上,环渤海地区海洋经济效率值与长三角地区、泛珠三角地区效率值相比始终处于最低状态,但三大经济圈差距明显;(2)中国海洋经济全要素生产率在研究期内呈现下降趋势,年均下降0.8%,主要由于海洋经济技术效率的下降;空间上由研究期初的中部高、两端低演变为期末的全国均衡发展,但南方差异较大;(3)通过Tobit模型对影响因素做出回归分析,得出海洋经济发展水平、海洋产业结构水平和海洋科研人力资本水平是海洋经济效率的驱动因素。  相似文献   

5.
西北太平洋沿海国海洋渔业资源可持续利用评价   总被引:2,自引:0,他引:2  
根据联合国粮农组织FAO提供的1950—2010年西北太平洋各沿海国的渔获生产统计数据,结合Fishbase提供的相关鱼种营养级(TL)以及Sea Around Us Project Database提供的无脊椎动物营养级,探讨了61年来西北太平洋各沿海国渔获物平均营养级的变化情况,以此判定各沿海国海洋渔业资源可持续利用情况。结果表明:除朝鲜外,其他沿海国均出现"捕捞对象沿着海洋食物网向下移动"的现象;中国、日本、韩国、俄罗斯渔获物平均营养级降低的速度分别为0.26/10a、0.21/10a、0.24/10a、0.15/10a;由于各国采取的渔业管理措施不同,导致各国渔业资源出现不同的现状。渔获物平均营养级的变化情况能够反映捕捞活动下各海域海洋生态系统的变化情况,建议西北太平洋各沿海国建立起基于渔获物统计的海洋渔业资源可持续利用评价监测系统,以掌握各国海洋生态系统结构和功能是否健康,为建立基于生态系统的渔业管理提供基础。  相似文献   

6.
在建设海洋强国和发展海南自贸区(港)等的战略背景下,海南省海洋渔业发展迅速,但诸如生态环境破坏,资源过度消耗等问题也随之发生,因此开展海南省海洋渔业生态经济发展效率研究对海南省渔业可持续发展具有重要意义。文章以海水养殖排污总量作为非期望产出,采用超效率SBM模型、标准差和变异系数,分析1998—2019年海南省海洋渔业生态效率的时空演变特征,并对海南省沿海市县的海洋渔业生态效率水平进行分类。研究结果表明:1998—2019年海南省各沿海市县海洋渔业生态经济效率整体处于中等水平,且呈波动下降趋势;各沿海市县海洋渔业生态经济效率有明显的区域差异,且呈波动增大趋势;各沿海市县海洋渔业生态经济效率可分为高效型、中效型和低效型3个类型,受边际效益递减和生态修复滞后性的影响,不同时期各市县效率类型不同。针对各市县不同生态效率类型,提出海洋渔业差异化发展策略,实现海南海洋渔业生态经济系统高质量发展。  相似文献   

7.
近年来,全球青潮发生的频率、规模及其危害效应呈现逐渐上升的趋势,而我国在该领域的研究尚未展开。为保障海洋渔业安全和生态系统稳定,应充分关注我国沿海爆发青潮的可能性与潜在危害。本文综述了青潮发生的机理与危害,解释了青潮、赤潮、绿潮的区别和联系,介绍了国际上防治青潮的一系列措施,并展望了青潮研究发展方向。  相似文献   

8.
中国沿海部分海区贝毒毒素的调查   总被引:6,自引:0,他引:6  
进入90年代以来 ,中国沿海的赤潮发生频率和强度有明显增加趋势。其中有毒赤潮所占的比例也有所增加。有毒赤潮生物产生的毒素能够在海洋生物中累积 ,影响海洋水产品品质 ,并对人类健康和海洋生物及生态系统造成威胁[1]。对我国沿海部分地区海洋生物的陆续调查也表明[2 ,3] ,由赤潮生物产生的毒素已经对我国沿海的一些贝类造成污染。本文通过对中国沿海部分海域贝毒毒素污染状况的调查 ,分析了这些地区的贝毒毒素污染状况 ,其中重点对胶州湾进行了长期定点监测 ,并与胶州湾浮游植物的动态变化情况进行了比较分析。1材料与方法1.…  相似文献   

9.
史磊  秦宏  刘龙腾 《海洋科学》2018,42(11):126-134
由于海洋渔业资源的衰退,目前世界海洋捕捞业进入"零增长"的徘徊期。当前世界海洋捕捞业呈现以下发展趋势:海洋渔业资源争夺日益激烈,海洋捕捞业管理制度日益严格,世界海洋捕捞业产业转移趋势日趋明显,海洋捕捞业技术装备要求越来越高,国际社会越来越重视海洋捕捞业可持续发展。面对世界海洋捕捞业的发展趋势,我国应当继续发展资源养护型海洋渔业,从生态系统角度考虑海洋捕捞业管理措施,积极稳妥发展远洋渔业,参与国际渔业资源的开发,重视海洋捕捞业装备技术水平的提高。  相似文献   

10.
唐议  邹伟红 《海洋科学》2009,33(3):65-70
海洋渔业对海洋生态系统的影响越来越受到人们的重视,考虑生态系统的管理已经成为海洋渔业管理的发展趋势.作者分析了海洋渔业对海洋生态系统产生的影响,包括捕捞活动对目标和非目标种产生的危害、渔业资源栖息地和环境破坏、生物多样性降低等;分析了国际上考虑生态系统的海洋渔业管理的法律框架、国际组织和有关国家的实践及其具体措施,指出了中国在此方面存在的问题:海洋生态系统的基础科学研究缺乏系统性和全面性;基于生态系统的海洋渔业管理的理论研究比较缺乏;相关的法律框架不够完善等.讨论了应用生态系统方法的海洋渔业管理与传统的海洋渔业管理间的关系,指出生态系统方法在其实践中将存在各种问题,认为生态系统方法应有选择地应用.对中国海洋渔业管理如何应用生态系统方法,建议:(1)加强海洋生态系统的基础科学研究;(2)开展基于生态系统的海洋渔业管理理论和方法研究;(3)逐步建立相关的法律和制度框架;(4)开展广泛的多部门合作和国际合作.  相似文献   

11.
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   

12.
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   

13.
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   

14.
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   

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《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   

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A set of 27 marine planktonic bacteria isolated from the polar regions was characterized by 16S rDNA sequencing and physiological and biochemical testing. More than half of these bacteria were positive for caseinase, gelatinase and 13-glucosidase, and could utilize glucose, maltose or malic acid as carbon source for cell growth. Twelve isolates expressed nitrate reduction activities. Except for one antarctic isolate BSwlO175 belonging to Actinobacteria phylum, these isolates were classified as γ-Proteobacteria, suggesting that γ-Proteobacteria dominated in cultivable marine bacterioplankton at both poles. Genus Pseudoalteromonas was the predominant group in the Chukchi Sea and the Bering Sea, and genus ShewaneUa dominated in cultivable bacterioplankton in the Prydz Bay. With sequence similarities above 97%, genus Psychrobacter was found at both poles. These 27 isolates were psychrotolerant, and significant 16S rDNA sequence similarities were found not only between arctic and antarctic marine bacteria ( 〉 99% ), but also between polar marine bacteria and bacteria from other aquatic environments ( ≥ 98.8% ), including temperate ocean, deep sea, pond and lake, suggesting that in the polar oceans less temperature-sensitive bacteria may be cosmopolitan and have a bipolar, even global, distribution at the species level.  相似文献   

20.
The relationship between the flux of exotic benthic foraminiferal tests (i.e. tests which are supplied from open-sea sources alone) in a tidal inlet and that of bulk sediment was analysed, which can be expressed as two first-order linear equations. According to this relationship, in order to determine net sediment transport directions in the entrance, the test concentration in surficial sediments of the tidal basin can be compared against a ‘ critical level ’. The critical level is determined for the conditions that no net transport of bulk sediment is present within the entrance. If the observed concentration (averaged over the tidal basin) is higher than the simulated critical level, then the net sediment transport is directed to landward. This method is applied to the analysis of net sand transport at Christchurch Harbour, a tidal inlet system located in southern England. In this investigation, concentrations of exotic foraminiferal tests in the surficial sediments of the tidal basin and ebb tidal delta area were obtained from the analysis of sea-bed sediment samples. A series of probable critical levels were calculated based upon the data sets with regard to: (1) sediment discharge from the rivers; (2) magnitude of sediment discharge within the entrance during the ebb; (3) the test concentration outside the harbour; (4) the thickness of the moving layer; and (5) two parameters associated with dispersive processes. The results show that the concentration in the tidal basin sediment is higher than a number of simulated critical concentrations for representative cases. Consequently, the high level of the concentration of exotic benthic foraminiferal tests within the harbour should be explained as a result of landward net transport of sands within the entrance.  相似文献   

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