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Conventional sectoral management and piecemeal governance are considered less and less appropriate in pursuit of sustainable development. Ecosystem based marine spatial management (EB-MSM) is an approach that recognizes the full array of interactions within an ecosystem, including human uses, rather than considering single issues, species, or ecosystem services in isolation. Marine spatial planning and ocean zoning are emerging concepts that can support EB-MSM. EB-MSM is driven by high-level goals that managers aim to achieve through the implementation of measures. High-level goals and objectives need to be translated into more operational objectives before specific targets, limits and measures can be elaborated.Monitoring, evaluation and adaptation are necessary to ensure that marine management measures are both effective and efficient. Solid monitoring frameworks are the foundation of adaptive management, as they provide the necessary information to evaluate performance and the effectiveness of management actions. Marine protected areas (MPAs) - possibly set up in networks - constitute a key component in EB-MSM policies and practises and have been applied as a cornerstone in conservation of marine biodiversity, management of fish populations, development of coastal tourism, etc. Moreover, MPA experiences have provided methods and concepts (such as zoning) to a wider EB-MSM context. The assignment of values to biophysical features of the marine environment allows the direct assessment of related management choices and may assist EB-MSM.A range of monetary valuation techniques have been proposed to reduce attributes of goods and services to a single metric. However, in the marine environment such an approach is often over simplistic, and thus less reductive techniques may be necessary. Rather than producing a single metric, the results of non-monetary assessments guide policy allowing weight to be given as necessary to potential areas of conflict and consensus.Strategies to take into account climate change effects and geohazard risks in EB-MSM have been applied or proposed worldwide. EB-MSM regimes must be alert to such risks and flexible to account for changes.  相似文献   

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选取辽宁獐子岛近岸海域大叶藻样品,对其须根、根状茎和不同生长阶段叶片的灰分含量、热值和元素含量(碳、氮、磷)及其相关性进行研究,结果表明:在不同生长阶段,叶片长度随着生长顺序先增大后减小;灰分含量随着叶片生长逐渐升高,且极显著小于根状茎和须根(P0.01);不同部位干质量热值差异极显著(P0.01),以初生叶最高,为(14.89±0.040)k J/g,后逐渐减小,在须根中最小,为(8.15±0.079)k J/g;不同生长阶段叶片的去灰分热值差异不大,但极显著大于须根和根状茎(P0.01);碳、氮、磷含量均呈同一趋势:初生叶幼叶成熟叶1成熟叶2衰老叶根状茎须根;N/P比值为27.08,说明大叶藻存在P限制;N/P比值在根状茎中最大,须根中最小,这说明大叶藻存在能量的转移和存贮;大叶藻不同部位灰分含量与干质量热值、去灰分热值、碳含量、氮含量、磷含量之间呈极显著的负相关(P0.01),干质量热值与碳含量、氮含量、磷含量之间呈极显著的正相关(P0.01);大叶藻不同部位的热值与碳、氮、磷元素含量之间均呈显著的线性关系(P0.05)。  相似文献   

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以香鱼卵母细胞为研究对象,采用观察卵内油球、有关酶的活力、以及卵的受精率和孵化率等变化的方法,研究了香鱼卵母细胞长时效演化的相关机理,结果表明,随着香鱼卵在腹腔内保存时间的延长,卵内油球从0h的油球直径≤10μm,且均匀分布,逐渐融合增大,至108h增大到120μm,油球数仅有5—6个。同时,SOD、POD的活力及MDA含量均呈先升后降的变化趋势,最大峰值分别出现在60h、36h和24h。随着油球和酶活的变化,卵子质量逐渐下降,表现为受精率和孵化率的降低:排卵后24h、48h、72h、96h的受精率分别为94.37%、88.19%、50.20%、10.83%,孵化率分别为85.78%、68.14%、25.54%、0.53%。  相似文献   

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以南太湖水华蓝藻铜绿微囊藻为材料,研究了温度、pH和氮、磷浓度对铜绿微囊藻生长的影响,为阐述微囊藻水华形成的机制提供科学依据。研究结果表明,铜绿微囊藻对温度的适应范围较广,15—40℃温度范围内铜绿微囊藻均可生长,25—30℃为铜绿微囊藻的最适生长温度,当温度达到45℃时,铜绿微囊藻停止生长并逐渐死亡。在pH6.5—9.5范围内,铜绿微囊藻均有较高的生长量,最适pH为8.0—9.0,pH值高于9.0时,铜绿微囊藻的最终生长量略有下降。BG-11培养基中添加高浓度的氮(1g/LNH4Cl)后,铜绿微囊藻的生长被显著抑制(P0.01),但同时添加不同浓度的磷(0.36—10mg/LKH2PO4)后,显著地提高了铜绿微囊藻的生长(P0.01),不同磷浓度处理之间无极显著差异,氮磷平衡是影响铜绿微囊藻生长的重要因素。  相似文献   

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Heavy metal concentrations were measured in the Changjiang Estuary and its adjacent waters. Results from a systematic survey in April 2002 to March 2003 indicate that the ranges of the concentrations of dissolved copper, lead, zinc and cadmium in the study waters are 1.01 - 6.86, 0. 10 - 0.39,3.17 - 9.12 and 0.011 - 0. 049 μg/dm^3 , respectively. Similar to zinc, the behavior of dissolved copper was essentially conservative, but high scatter has been observed for high salinity samples, which can be attributed to the decomposition or mineralization of organic matter by bacteria. Dissolved lead may have active behavior with an addition at high salinity. Overall concentrations of dissolved cadmium increase with salinity. The mean values of these dissolved metals calculated for the surface waters were higher than those for the middle and bottom ones. External inputs of dissolved heavy metals to the surface waters were the likely explanation for these higher values. The maximum seasonal average values of dissolved copper and zinc were found in summer, reflecting higher amounts of riverine input in this season. In contrast, the maximum seasonal average values of dissolved lead and copper were found in winter and the lowest ones in summer, respectively, which might be asso- ciated with a combination of low concentration with heterogeneous scavenging. Concentrations of these dissolved metals found for the Changjiang Estuary fall in the range observed for the other estuaries but are noticeably higher than those from uncontaminated rivers, except for cadmium. Compared with observations for the Changjiang Estuary in the last two decades, it is clear that the Changjiang estuarine waters has been contaminated with copper, lead, zinc and cadmium during China' s industrialization, but concentrations of them have decreased in the last few years.  相似文献   

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Three species,Bathynomus decemspinosus,B.doederleini and B.kensleyi (Crustacea,Isopoda,Cirolanidae),are reported for the first time from the Parangipettai coastal waters,Southeast coast of India.Several Trilasmis (Temnaspis) tridens (Cirripedia Thoracica,Lepadomorpha) were attached to the pleopods of some individuals.So,five bathynomid species are currently reported from India.  相似文献   

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In coastal environments, fine-grain sediments often aggregate into large and porous flocs. ElectroMagnetic Current Meters (EMCM) and Laser In Situ Scattering and Transmissometry (LISST-ST) have been deployed within a Spartina alterniflora marsh of the Luoyuan Bay in Fujian Province, China, to measure the current velocity, the floc size and the settling velocity between 15 and 22 January 2008. During the observations, the near-bed water was collected in order to obtain the suspended sediment concentration (SSC) and constituent grain size. Data show that: (1) the nearbed current velocities vary from 0.1 to 5.6 cm/s in the central Spartina alterniflora marsh and 0.1–12.5 cm/s at the edge; (2) the SSCs vary from 47 to 188 mg/dm 3 . The mean grain size of constituent grains varies from 7.0 to 9.6 μm, and the mean floc sizes (MFS) vary from 30.4 to 69.4 μm. The relationship between the mean floc size and settling velocity can be described as: w s =ad b , in which w s is the floc settling velocity (mm/s), a and b are coefficients. The floc settling velocity varies from 0.17 to 0.32 mm/s, with a mean value of 0.26 mm/s, and the floc settling velocity during the flood tide is higher than that during the ebb tide. The current velocity and the SSC are the main factors controlling the flocculation processes and the floc settling velocity.  相似文献   

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中性糖作为有机质的重要组分,其丰度和组成对于沉积物中有机质的来源和降解等生物地球化学过程具有重要的指示意义。本文在对2009年和2010年采集自东海的24个表层沉积物中有机质和中性糖组成以及分布特征进行分析的基础上,探讨了中性糖及其组分在指示东海表层沉积物有机质来源和降解程度中的作用。结果表明:东海表层沉积物中有机碳(TOC)和中性糖(NS)含量较高,分别为66.8—1441.7?mol/g和0.40—4.87?mol/g,平均浓度分别为(409.4?55.2)?mol/g和(3.07?0.31)?mol/g,NS占有机碳的碳摩尔百分数为1.88%—8.93%;随着沉积物粒径增大,TOC、NS含量降低,NS中的葡萄糖组分摩尔百分数增大,而半乳糖、甘露糖和木糖组分摩尔百分比减小,表明沉积物中有机质降解程度增大。同时发现,葡萄糖和海藻糖的摩尔分数之和与半乳糖和阿拉伯糖的摩尔分数之和的比值可作为判断沉积有机物降解程度的指标,其值越大,说明沉积有机物的生物降解程度越小。  相似文献   

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广东省南澳海域是粤东重要的海产养殖基地, 分析该海域浮游动物群落结构特征对评估其生态环境质量具有重要意义。文章根据2014年9月(秋季)、12月(冬季)、2015年4月(春季)和2016年7月(夏季)在南澳岛东部海域的浮游动物调查, 分析该海域浮游动物的群落结构特征, 探讨环境因素对其时空分布的影响。共鉴定浮游动物206种(包括浮游幼虫), 桡足类种数最多, 达94种; 远岸海域浮游动物的种数高于近岸海域。浮游动物丰度和生物量的季节变化明显, 夏、秋季高于冬、春季; 浮游动物丰度和生物量的分布趋势较一致, 夏季高值区主要出现在近岸, 秋季由近岸向远岸海域递增。浮游动物不同类群和优势种的丰度也存在季节变化, 桡足类是调查期间丰度较高的类群, 秋季水母类和海樽类丰度明显增加; 优势种后圆真浮萤(Euconchoecia maimai)和针刺真浮萤(Euconchoecia aculeata)在夏季丰度高, 小齿海樽(Doliolum denticulatum)在秋季占绝对优势。温度、盐度和浮游植物生物量是影响南澳岛东部海域浮游动物时空变化的主要环境因子, 说明该海域浮游动物群落特征受海流、水团和养殖活动的综合影响。  相似文献   

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海洋源生防细菌LHB02的筛选、鉴定及其抑菌谱检测   总被引:1,自引:1,他引:0       下载免费PDF全文
从高度污染的海滩污泥中,分离得到一株对部分水产病原菌有很强拮抗作用的生防细菌LHB02。采用细菌的通用引物进行LHB02的16SrRNA基因片段扩增,得到l511bp的DNA片段,其序列与枯草芽孢杆菌(Bacillus subtilis)在进化位置上最为接近,结合传统的形态学、生理生化鉴定手段,鉴定该菌株为枯草芽孢杆菌...  相似文献   

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通过对胶州湾东北部滨海湿地5个站点盐渍土壤和其上生长的碱蓬中的微量碱金属、碱土金属Li、Rb、Cs、Sr、Ba的系统研究,发现盐渍土壤中Li、Sr和Ba的含量高于我国土壤背景值,Rb、Cs的含量特别是Cs的含量低于我国土壤的背景含量,盐渍土壤中Li/Cs比值和Ba/Sr比值较为接近,并且Li和Cs、Sr和Ba之间具有显...  相似文献   

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Managed realignment (MR) is a ‘soft’ engineering technique that involves the deliberate landwards retreat of the existing line of coastal defence and subsequent tidal inundation of land. Managed realignment has been established worldwide for over 30 years and its goals may include habitat restoration, recovery of biodiversity and sustainable coastal defence. In southeast England in particular, an increasing number of MR sites (20–110 ha) have been commissioned in the last decade in response to increasing coastal habitat loss and sea-level rise. Following initial sea wall breaching and site flooding, monitoring of these sites is usually carried out for a period of 5 years and during this time changes in ecosystem structure can be easily observed. However, there is a poor understanding of the long-term effects of flooding on soil physicochemical parameters including sediment geochemistry and geochemical cycling, nutrient fluxes and soil maturation processes. Such physical and chemical changes may continue to take place over time-scales exceeding 5 years and therefore current monitoring practices may not be sufficient.  相似文献   

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采用干法授精方法获得受精卵,在人工培育条件下观察了光唇鱼胚胎及仔、稚鱼发育过程。结果表明,光唇鱼受精卵呈圆球形,沉性、弱粘性。在水温23—25℃下,胚胎发育历时46h45min,经历了胚盘形成、卵裂、囊胚、原肠胚、神经胚、器官形成和孵化等阶段。在水温24—27℃下,仔、稚鱼发育历时22d,初孵仔鱼具有较大的卵黄囊,胸鳍原基及肛门原基形成;4日龄仔鱼开口摄食,进入混合营养期;7日龄仔鱼卵黄囊消失,营外源性营养,体侧8条横斑形成,各鳍均已出现,进入晚期仔鱼阶段;14日龄仔鱼各鳍鳍条发育基本完成;16日龄仔鱼鳞片开始出现,进入稚鱼期;22日龄稚鱼全身被鳞,进入幼鱼期。  相似文献   

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在对照饲料中添加不同水平的硫酸铜、富马酸铜和蛋氨酸铜,使硫酸铜组铜离子含量为32mg/kg,富马酸铜和蛋氨酸铜组铜离子含量分别为16mg/kg、32mg/kg和48mg/kg,共组成8种饲料(饲料编号为对照、Sul-32、Fum-16、Fum-32、Fum48、Met-16、Met-32和Met-48),饲喂凡纳滨对虾(初重0.74±0.01g)8周。结果表明,饲料中添加三种铜源均能不同程度提高凡纳滨对虾的特定生长率(SGR)、存活率(Survival)和蛋白质效率(PER),降低饲料系数(FCE)。其中,Met-16和Fum-32组的SGR显著高于对照组(P0.05),Met-16、Met-32和Fum-32组的PER显著高于其它各组(P0.05);不同铜源对凡纳滨对虾的体组成没有显著影响(P0.05),但Met-32组的肝体比(HSI)显著下降(P0.05)。各组间血清铜蓝蛋白(CER)含量差异不显著(P0.05),Met-16和Fum-32组的生长激素(GH)含量则显著高于对照组(P0.05)。本研究结果表明,饲料中三种铜源能不同程度的提高凡纳滨对虾的生长性能,但相同浓度有机铜离子的生物利用率优于无机铜,其顺序为:蛋氨酸铜富马酸铜硫酸铜。饲料铜对凡纳滨对虾的促生长作用可能是通过提高体内相关抗氧化酶的活性及刺激生长激素的分泌来实现的。  相似文献   

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