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1.
不同形状和材料的鱼礁模型对短蛸诱集效果的初步研究 总被引：2，自引：0，他引：2
采用鱼类行为学方法,观测了短蛸(Octopus ocellatus)对同为PVC材质的3种形状的有孔和无孔模型礁以及对同为管状的3种不同材料的单体和叠加模型礁的行为反应,并对各组内模型礁的诱集效果进行了比较.实验结果表明:未投放模型礁条件下短蛸在水槽四角分布率较高,在鱼礁标志区分布率只有0.5%;PVC材质3种形状的模型礁放入后对短蛸的聚集率均在10%以上,其中内部空间最大的正方体模型礁聚集率最大,每种形状的模型礁中有孔模型礁聚集率高于无孔;3种不同材料的管状模型礁放入后诱集效果均较明显,其中陶瓷材质的管状模型礁效果最好,每种材料的模型礁中3单体叠加后的组合礁聚集率明显高于单体,其中叠加后的陶瓷模型礁对短蛸的聚集率达到39.3%;研究发现短蛸的领域行为对鱼礁模型的诱集效果影响较大. 相似文献
2.
为了解不同类型人工鱼礁的集鱼效果, 在试验水槽内观察5种鱼礁模型对花尾胡椒鲷Plectorhynchus cinctus的诱集效果.结果表明: 在未投放礁体模型时, 试验鱼的密集区均出现在水槽的左端(A1和A6区), 出现率为61.60%, 而试验鱼在空白礁区(A3和A8区)的平均出现率低于5%;在A3和A8区中间放入鱼礁模型后, 鱼礁区(即A3和A8区)试验鱼的出现率分别上升至32.53%(B礁)、37.60%(C礁)、20.93%(D礁)、28.13%(E礁)、29.20%(F礁), 而原密集区A1和A6试验鱼的平均出现率分别下降至29.47%(B礁)、23.47%(C礁)、33.60%(D礁)、25.73%(E礁)、42.93%(F礁).统计数据显示, 5种礁体模型放入后, 礁区内试验鱼的平均出现率与投放前相比均大幅度提高, 说明5种模型礁对试验鱼均有较强的诱集效果, 其中有效空间较大, 遮盖效果较好的C礁的诱集效果最好. 相似文献
3.
试验水槽中多种人工鱼礁模型组合对紫红笛鲷幼鱼的诱集效果 总被引：2，自引：0，他引：2
摸清多种人工鱼礁模型组合对紫红笛鲷幼鱼的诱集效果,可为人工鱼礁礁体组合设计和礁区布局设计等方面提供科学依据.本研究参照深圳杨梅坑人工鱼礁区的实际建礁情况,制作并模拟4组三种模型礁体组合、4组四种模型礁体组合,在方形试验水槽中以鱼类行为学的方法研究了这8组模型礁体组合对紫红笛鲷的诱集效果.4组三礁组合礁体模型试验结果表明,FHJ三礁组合对紫红笛鲷的集鱼效果非常明显,BFH、BCG、CHJ三礁组合对紫红笛鲷的集鱼效果较为明显.其诱集效果排序为:FHJ组合礁(53.84%)>BFH组合礁(44.85%)>BCG组合礁(38.11%)>CHJ组合礁(36.01%).4组四礁组合礁体的试验结果表明,4组四礁组合礁体模型对紫红笛鲷均具有较强的诱集效果,其诱集效果排序为:BGHJ组合礁(52.27%)>CFHJ组合礁(51.26%)>BCGJ组合礁(50.01%)>BCGH组合礁(45.05%).总体上,四礁组合的诱集效果优于三礁组合,人工鱼礁建设的礁群配置以多礁组合为佳. 相似文献
4.
《中国海洋大学学报(自然科学版)》2017,(6)
实验室条件下,研究了正方体人工礁7个不同引入数量比例(0~60%)和人工礁摆放布局(每个数量比例设置10个布局)对许氏平鲉(Sebastes schlegelii)聚集率的影响,确定了单位面积正方体人工礁的适宜投放数量和礁体摆放布局,得出单位鱼礁的适宜布设方案。在此基础上,探讨了大泷六线鱼(Hexagrammos otakii)和许氏平鲉的种类、密度和鱼体规格对聚集率的影响。研究显示,单体礁引入数量比例50%时,数量比例与许氏平鲉聚集率呈显著正相关线性关系,且摆放布局对许氏平鲉的聚集率有显著影响;单体礁引入数量比例为50%时,许氏平鲉的聚集率达到最大值(76%),显著高于0~40%处理组(P0.05),且当单体礁引入数量比例达到50%和60%时,礁体摆放布局对许氏平鲉聚集率的影响无统计学意义(P0.05)。在适宜布设方案条件下,种类和密度对试验鱼聚集率的影响均达到显著性水平(P0.05);鱼体规格对大泷六线鱼的聚集率无显著影响,对许氏平鲉的聚集率影响显著。结果表明,正方体人工礁单位鱼礁的适宜单体礁引入数量比例为50%,在该数量比例时,单体礁摆放布局对恋礁性鱼类的聚集效果无显著影响。 相似文献
5.
鱼礁模型对赤点石斑鱼的诱集效果 总被引：10，自引：0，他引：10
本文在实验室中水池中观察了赤点石斑鱼在三种不同口径鱼礁模型存在下的行为，结果表明；鱼礁对这种鱼有明显诱集效果，随着模型口径的增大，鱼在礁体放置区分布百分率有增大趋势，而鱼个体平均距离、群体总重心与礁体平均距离和鱼与礁的距离均有减小趋势。可见，口径大小的鱼礁模型有较好的聚鱼效果。 相似文献
6.
参考相关资料对比水泥类、油井类、舰船类及其他类型人工鱼礁对海洋生物诱集效果,探讨不同材料人工鱼礁在诱集效果上的差异.结果表明,人工鱼礁区生物诱集效果高出天然礁区(对照区)的比率达68.75％.不同材料类型人工鱼礁的生物诱集效果存在差异:水泥类人工鱼礁生物诱集效果高于天然礁区的比率为71.43％;油井类人工鱼礁生物诱集效果高于天然礁区的比率为50.00％;舰船类人工鱼礁生物诱集效果高于天然礁区的比率为100.00％;其他类人工鱼礁生物诱集效果高于天然礁区的比率为80.00％.研究资料分析表明人工鱼礁的建设,需要更多地结合海洋物理、海洋化学、海洋生物等方面的知识,以提高人工鱼礁对海洋生物的增殖效果,促进其生态效益、经济效益和社会效益共同提高. 相似文献
7.
海洋油气平台在达到作业寿命后必须进行废弃处置，将海上退役平台改作人工鱼礁投放，对优化渔业资源、促进海洋经济持续发展具有重要意义。基于平台拆卸结构，共制作了箱状、管状、柱状、网状4种典型鱼礁实物模型，通过室内模拟试验和数值模拟研究，分析了不同鱼礁类型单体的稳定性和流场效应。结果表明：开口率0.1至0.8的箱状礁的稳定性均能满足要求，但开口率高于0.6的箱状礁难以形成连续的背涡流区域，设计时应使开口率低于0.6；管状礁应选择堆叠放置方式投放，且堆叠层数与稳定性和流场造成能力均呈正相关，在设计时尽量提高管状礁的堆叠层数；柱状礁设计时应尽量降低其重心，并减小迎流投影面的中空面积投放；基于平台的钻井架、火炬臂、栈桥设计的3种网状礁，均满足礁体稳定条件，且均能形成大范围的背涡流区域，可作为人工鱼礁投放。研究成果为平台造礁礁体结构设计提供了理论依据与实践基础，对海上退役平台的废弃处置具有一定的参考价值。 相似文献
8.
阴影效应是影响人工鱼礁诱集效果的主要因素之一，为研究许氏平鲉(Sebastes schlegelii)对人工鱼礁不同阴影情况的行为响应，采用室内模拟实验方法，在实验水槽顶部固定光源，共设计3组实验：A组实验探究不同阴影面积的鱼礁模型对实验鱼的诱集效果；B组实验探究不放置鱼礁模型、悬挂不同开孔率顶板对实验鱼的诱集效果；C组实验探究阴影面积相同但开孔数量不同的鱼礁模型对实验鱼的诱集效果；对照组实验水槽中不放置鱼礁模型、不悬挂顶板。观察并记录许氏平鲉幼鱼(体长(5.06±0.09)cm,体质量(3.22±0.16)g)在水槽中的行为与分布特征。研究表明：3个实验组中许氏平鲉在鱼礁放置区域的出现率均显著高于对照组和其他区域；A组实验中，许氏平鲉在鱼礁放置区的平均出现率随着鱼礁阴影面积的增大而上升；B组实验中，许氏平鲉在顶板放置区的平均出现率显著高于对照组，但不同水平组之间差异不显著；C组实验中，开孔数为1时许氏平鲉在鱼礁放置区的平均出现率与开孔数为9时相近且高于开孔数为4和6时。研究结果表明，阴影面积越大的人工鱼礁对许氏平鲉的诱集效果越好，阴影面积相同时开孔数较多的人工鱼礁能够在提供良好庇护所... 相似文献
9.
布设间距对人工鱼礁流场效应影响的数值模拟 总被引：10，自引：0，他引：10
人工鱼礁在海中不同的布局方式会产生不同的流场效应.通过水槽与风洞模型实验很难对组合鱼礁流场全局进行观测,为此提出1种基于CFD原理的人工鱼礁流场特性的计算机数值模拟方法,模拟了不同流速条件下布设间距对方形组合礁体流场效应的影响.结果表明:数值模拟较好地反映了人工鱼礁周围上升流和背涡流的分布情况;当两礁体布设间距为1.5倍礁体尺寸时,所产生的上升流高度达到最大值;当布设间距为1倍/时,其上升流的影响面积为最大;当布设间距为1.5倍时所产生的背涡流效果最好;两礁体之间的最佳布设间距应为礁体尺寸的1～1.5倍.数值模拟结果与风洞实验结果基本相符,该结论可为人工鱼礁实际投放提供理论参考. 相似文献
10.
人工鱼礁对山东莱州朱旺港海区游泳动物的群落结构及季节变化的影响 总被引：1，自引：0，他引：1
为查明朱旺港人工礁区游泳动物的群落结构特征及其季节变化,于2010年5～11月和2011年3月对该海域人工礁区和自然对照区进行逐月调查.结果表明,人工礁区游泳动物种类比对照区丰富(1.42倍);并且人工礁区的Margalef种类丰富度指数、Shannon-Wiener多样性指数、Pielou均匀度指数均高于对照区.人工礁区的CPUE也明显高于对照区,人工礁区的Al区(建于2008年)和A2区(建于2009年)分别是自然对照区CA区的1.43和1.55倍,其中经济种类日本蟳的CPUE分别达到2.69和2.97倍.初步体现人工鱼礁投放后的集鱼效果,且礁区游泳动物的群落结构有明显改善. 相似文献
11.
Arne Schnack-Friedrichsen Angela M. Davis Jim D. Bennell Dei G. Huws 《Marine Georesources & Geotechnology》2001,19(4):221-243
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.
Shigehisa Nakamura 《Marine Geodesy》2000,23(1):55-61
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
13.
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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15.
《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
16.
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
17.
Coastal inundation associated with extreme sea levels is the main factor which leads to the loss of life and property whenever a severe tropical cyclonic storm hits the Indian coasts. The Andhra and Orissa coasts are most vulnerable for coastal inundation due to extreme rise in sea levels associated with tropical cyclones. Loss of life may be minimized if extreme sea levels and associated coastal flooding is predicted well in advance. Keeping this in view, location specific coastal inundation models are developed and applied for the Andhra and Orissa coasts of India. Several numerical experiments are carried out using the data of past severe cyclones that struck these regions. The simulated inland inundation distances are found to be in general agreement with the reported flooding. 相似文献
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19.
Hoi-Soo Jung Kap-Sik Jeong Yong-Shik Chu Sung-Hyun Park Ki-Hyune Kim 《Marine Georesources & Geotechnology》2001,19(3):181-195
Grain size and water content in box-core sediments from the Clarion-Clipperton fracture zone (C-C zone) in the northeast equatorial Pacific were analyzed in detail to understand the downcore variations across a hiatus between Quaternary and Tertiary layers. Grain-size distributions in the topmost core sediments show two modes: a coarse mode (peaked at 50 μm) and a fine mode (at 2-25 μm). The coarse mode disappears gradually with depth accompanied by the dissolution of siliceous fossil tests, whereas the fine mode coarsens due to the formation of authigenic minerals. Water content increases abruptly across a color boundary between an upper pale brown layer and a lower dark brown layer that is the hiatus between Quaternary and Tertiary layers. Abundant smectites and microvoid molds, which are created by the prolonged fossil dissolution in the underlying sediment, are attributed for the abrupt downcore variation of water content. Overall variations in grain size and water content in the topmost core sediments in the western C-C zone are possibly constrained by the dissolution of biogenic siliceous fossils. Variations in geotechnical properties related to these changes must be considered in the design of nodule collectors. 相似文献
20.
Shigehisa Nakamura 《Marine Geodesy》2001,24(1):27-33
This article concerns an interrelation between the sea levels and the western boundary flow near a tectonic boundary in a local zone in the Northwestern Pacific. In this zone, sea level variations at stations located on the coast facing the Pacific are studied to find the interrelation between variations of the Kurosio flow as an index of the distance of the flow axis off a specific coast. The result is discussed after data processing of the monthly means of the sea levels, and a notice is taken of variations caused by active crustal upheavals during a seismic event, a local earthquake. 相似文献