改性黏土法消除球形棕囊藻赤潮的现场实验与效果评估     

曹西华  俞志明  邱丽霞 《海洋与湖沼》2017,48(4):753-759

球形棕囊藻是一种具有复杂异型生活史的有毒有害赤潮生物,近年来在我国近海频繁暴发成灾,形成的巨大囊体为国内外罕见。迄今还未见到有效消除囊体型球形棕囊藻赤潮的方法报道。本文通过海上围隔实验和现场赤潮消除工程跟踪监测,考察了喷洒改性黏土消除囊体型球形棕囊藻赤潮的可行性与效率,并分析了改性黏土法治理赤潮时对水体及沉积环境的可能影响。围隔实验结果表明,喷洒改性黏土可以有效消除水体中过量的微藻细胞,其中以少量多次喷洒方法的效果最好,生物量(chl a)去除率90%。在对2016年2月广西防城港附近海域球形棕囊藻赤潮消除时的跟踪监测结果表明,改性黏土法适用于工程化消除赤潮作业,能够快速消除水体中的大量球形棕囊藻囊体,随改性黏土絮凝体沉入海底的赤潮藻可以快速分解而失去活性。喷洒改性黏土对于赤潮水体的主要理化指标影响不显著,所监测的水体COD、pH和不同形态氮、磷、硅等生源要素浓度都在原有水质水平范围内波动。  相似文献   

Influence of lunar phases,winds and seasonality on the stranding of mesopelagic fish in the Strait of Messina (Central Mediterranean Sea)          下载免费PDF全文

Pietro Battaglia  Giovanni Ammendolia  Mauro Cavallaro  Pierpaolo Consoli  Valentina Esposito  Danilo Malara  Ignazio Rao  Teresa Romeo  Franco Andaloro 《Marine Ecology》2017,38(5)

The shore stranding of mesopelagic fauna is a recurrent phenomenon in the Strait of Messina (Central Mediterranean Sea). The aim of this paper is to test the influence of lunar phases, winds and seasons upon the frequency of occurrence of strandings of mesopelagic fish. Species abundance in relation to these factors was quantified for the first time. Specimens were collected stranded on the shore along the Sicilian coast of the Strait of Messina between 2008 and 2016. Overall 32 species belonging to seven families (Gonostomatidae, Microstomatidae, Myctophidae, Paralepididae, Phosichthyidae, Sternoptychidae, Stomiidae) were found stranded. Myctophidae was the family including the highest number of species (16), whereas Gonostomatidae was the most abundant in terms of total number of individuals (47.2%), mainly thanks to the species Cyclothone braueri. The moon, which influences the strength of currents (highest during full and new moon phases) and irradiance (higher in some lunar phases, such as the full moon), affected the abundance of stranded mesopelagic fish in the study area. The highest number of stranding events was recorded during the new moon: 34.6% of the total relative abundance of stranded mesopelagic fish. Wind blowing from the sea towards the coastline (southeasterly and easterly winds) created the best conditions for strandings. The highest abundance of stranded specimens was recorded during the winter season.  相似文献   

Recreational use of offshore wind farms: Experiences and opinions of sea anglers in the UK     

《Marine Policy》2017

The expansion of offshore wind farms (OWFs) is likely to increase conflict with other marine users as different sectors compete for space. There may also be positive interactions, as the artificial reef effects from energy infrastructure have the potential to sustain and enhance fishing opportunities. Recreational sea angling is an important sector within the UK but the experiences and opinions of UK sea anglers with respect to OWFs have not been documented. To address this, an online survey was undertaken with recreational anglers around the UK (n=199). Respondents represented a range of socio-demographic and angling characteristics, although male, more frequent and older fishers as well as club members were over-represented compared to a 2012 national survey. One quarter of the respondents had fished around the perimeter of or within an OWF, most on multiple occasions, and 73% of those who had not expressed a willingness to do so in future. Anglers reported both positive and negative effects on catch success when fishing near or within OWFs compared to their experiences of the same site prior to OWF development. Outcomes for individual species were also mixed. Anglers recognised the potential artificial reef effects of OWFs and their role as a “safe haven”, particularly due to the exclusion of commercial fishers. Negative perceptions included restricted access, harm to marine wildlife, and visual impact. There is little evidence that OWFs will have a significant economic impact on recreational fishing, as most anglers are unlikely to change their behaviour in response to future developments.  相似文献   

Business case for mussel aquaculture in offshore wind farms in the North Sea     

《Marine Policy》2017

The European Blue Growth strategy aims to expand the new maritime sectors of aquaculture, energy, biotechnology, coastal tourism and mineral mining. Growth of these sectors will increases pressure on the seas, particularly on those areas that are densely used by traditional sectors such as fisheries and transport. This has triggered interest in developing multiuse of space and multiuse platforms at sea. This paper assesses the feasibility of offshore mussel production project in wind farms by design and ex-ante evaluation of a mussel aquaculture system in the North Sea. A system for mussel cultivation in the Dutch Borssele offshore wind farm was designed, producing both mussel seed and consumption-sized mussels with semi-submerged longlines. Based on the economic model and the risk assessment, this paper concludes that mussel aquaculture is an appealing commercial model for increased returns in offshore wind farms. The economic models shows that the internal rate of return and net present value are positive and based on the sensitivity analysis, it can be concluded that these results are robust.  相似文献   

SWAN模型中不同风拖曳力系数对风浪模拟的影响   总被引：1，自引：1，他引：0  

丁磊  于博 《海洋学报》2017,39(11):14-23

本文以荷兰哈灵水道海域为实验区域,通过敏感性实验,研究了在14 m/s、31.5 m/s和50 m/s（分别代表一般大风、强热带风暴和强台风的极端条件）定常风速下SWAN模型中不同风拖曳力系数对风浪模拟的影响程度。结果表明,对于近岸浅水区域（水深小于20 m）,风拖曳力系数计算方案的选择对有效波高影响较小,而且当风速增加到一定程度后,波浪破碎成为影响波高值的主要因素;对于深水区域（水深大于30 m）,一般大风条件下风拖曳力系数计算方案的选择对有效波高影响仍然较小,随着风速的继续增大,风拖曳力系数计算方案的选择对有效波高的影响逐渐显著。对于平均周期,风拖曳力系数计算方案的选择和风速的改变对其影响均较小,而由水深变浅导致的波浪破碎对其影响较为显著。根据敏感性实验结果,本文对SWAN模型中风拖曳力系数计算方案的选择做出如下建议:计算近岸浅水区域风浪场或深水区域一般大风条件风浪场时,其风拖曳力系数可以直接采用模型默认选项;而对于深水区域更大风速条件,可首先采用模型默认选项试算,然后结合当地海域实测波浪资料进行修正。  相似文献   

Using input–output methods to assess the effects of fishing and aquaculture on a regional economy: The case of Galicia,Spain     

《Marine Policy》2017

This paper uses an input–output model to quantify the socioeconomic impact of fishing and aquaculture on Galicia, one of Spain's most important maritime regions. Results indicate that the carryover effects of these production activities are important for Galicia's economy because they contribute not only to job creation but also to possibilities for obtaining income in other economic sectors. These sectors’ combined production in 2013 was almost a million euros, and that production was estimated to account for nearly 2% of the regional economy's value added and for more than 17,000 full-time jobs. Together these contributions amounted to some €1.7 billion in production and €975 million in value added to other Galician economic activities. At the same time, fishing and aquaculture were responsible for creating the equivalent of more than 14,000 full-time jobs in other economic activities.  相似文献   

1509号台风灿鸿期间“朱家尖-嵊山”高频地波雷达数据分析          下载免费PDF全文

李程  李欢  王慧  高佳  王国松  董军兴  潘嵩  刘克修 《海洋学研究》2017,35(1):41-46

2007年在朱家尖和嵊山布设了小型阵变频高频地波雷达,对共同覆盖范围内的舟山海域进行风、浪、流的业务化探测。2015年7月11日,1509号台风灿鸿在朱家尖沿海登陆,之后继续向北偏东方向移动,台风中心经过高频地波雷达探测海域。本文将台风期间高频地波雷达的探测数据分别与定点浮标观测数据和ASCAT卫星遥感大面积风场数据进行了对比分析。结果表明,高频地波雷达在台风期间较好地反映了舟山海域流场特征和风场分布情况,高频地波雷达的探测数据精度满足指标要求,验证了高频地波雷达在复杂海况条件下具有合格的探测性能。  相似文献   

基于风廓线雷达观测的台风“天兔”边界层演变特征研究     

廖菲  邓华  高志球  陈伯纬 《海洋学报(英文版)》2017,36(9):39-44

垂直探测台风边界层特征对于认清台风结构具有重要意义。基于1319号台风“天兔”途经的三个边界层风廓线雷达站的观测资料,结合探空数据,本文分析了“天兔”的边界层径向、切向风特征,结果表明：1）最大切向风速出现在眼区附近,在“天兔”稳定维持为强台风级别期间,最大切向风速基本稳定在1800 m高度左右,随着登陆后强度的迅速减弱,最大切向风速减弱、最大切向风速垂直范围缩小;2）最大风速所在高度和台风入流层顶高基本相近,大于依据理查森数或位温梯度所判断出的边界层高度,而基于信噪比（SNR）或其梯度所判断的混合层高度时常偏低;3）“天兔”登陆前边界层高度可以达到2100 m以上,在台风级别及以上时,各站观测到的边界层高度变化不大,基本在1200～1600 m之间,登陆后随着台风强度的减弱,边界层高度迅速减小。  相似文献   

风浪流中半潜式风机系统动力响应特性研究     

毛莹  范菊  张新曙  尤云祥 《海洋工程》2017,35(1):60-70

以三浮筒(Tri-floater)型半潜式风机系统为对象,采用时域方法,考虑垂荡板的黏性阻尼效应,研究系泊缆直径、长度、预张力和布置方式等参数对其在风浪流中动力响应特性的影响规律,提出了一种系泊参数优化方法。在此基础上,根据东海和南海三个不同水深区域百年一遇海洋环境条件,通过调整Tri-floater型浮式基础的吃水和垂荡板等参数,有效地提高了其运动响应周期,减小了其运动响应幅值。同时,根据风机浮式基础运动幅值的设计规范要求,针对三个不同水深区域特点,设计了Tri-floater型浮式基础的系泊系统。计算结果表明,改进后的Tri-floater型半潜式风机系统能满足百年一遇极端环境下的作业要求,适合于东海和南海海洋环境下海上风能资源的开发。  相似文献   

10MW级海上浮式风机运动特性研究   总被引：2，自引：2，他引：0  

徐应瑜  胡志强  刘格梁 《海洋工程》2017,35(3):44-51

以DTU 10 MW基准风机为研究对象,单柱式平台作为基础支撑结构,使用FAST软件计算分析,考虑单独风、单独波浪以及风浪组合三种环境条件,对10 MW级海上浮式风机的运动特性进行研究。研究发现:系统摇荡是风激励的低频运动和波浪激励的波频运动的合成,气动阻尼削弱系统的波频运动;系统纵荡和纵摇运动存在明显的耦合现象,而垂荡运动和其他方向的运动没有耦合关系;受纵摇影响,转动的风轮产生陀螺惯性力矩,激励首摇运动;随着风机单机容量的增加,风激励的低频运动比例增大,波浪激励的波频运动比例减小。  相似文献