Catch-quota balancing in multispecies individual fishing quotas   总被引：2，自引：1，他引：2  

James N. Sanchirico  Daniel Holland  Kathryn Quigley  Mark Fina   《Marine Policy》2006,30(6):767-785

Individual fishery quotas (IFQs) are an increasingly prevalent form of fishery management around the world, with more than 170 species currently managed with IFQs. Yet, because of the difficulties in matching quota holdings with catches, many argue that IFQs are not appropriate for multispecies fisheries. Using on-the-ground-experience with multispecies IFQ fisheries in Iceland, New Zealand, Australia, and Canada, we assess the design and use of catch-quota balancing mechanisms. Our methodology includes a mix of interviews with fishery managers, industry representatives, and brokers, literature review, and data analysis. We find that a combination of incentives and limits on use rates for the mechanisms provide sufficient flexibility to the quota owner without the fishery manager incurring excessive levels of overexploitation risk. Contrary to some opinions, these programs are evidence that it is possible to implement IFQ programs for multispecies fisheries and that they can be profitable and sustainable.  相似文献   

Palynological Evidence on Climate Changes in the East China Sea During Mid and Late Holocene     

李珍  王永吉  刘振夏  蓝东兆 《海洋通报(英文版)》2001,3(2)

The pollen analysis of DGKS9617 core in the East China Sea (covering about the last 6800 years) shows five obvious pollen assemblages and seven sub-assemblages. Combined with the sediment and the result of diatom analysis, the climate changes are reconstructed during the Middle and Late Holocene. Corresponding to the pollen assemblages, the climate shifts just as follows: Assemblage Ⅰ-Warm and Dry Stage, Assemblage Ⅱ-Cool and Humid Stage, Assemblage Ⅲ-Hot and Dry Stage (the mean annual temperature is 2～3 ℃ higher than that today ), Assemblage Ⅳ-Cool and Humid Stage, Assemblage Ⅴ-Wann and Dry Stage. The third stage is divided into three substages i.e. a slight colder and dry one, a slight wanner and humid one and a slight warmer and dry one. During the fifth stage, the climate becomes similar to that today with three warm substages and two cool substages.  相似文献   

The flow of Atlantic water to the North Icelandic Shelf and its relation to the drift of cod larvae   总被引：1，自引：0，他引：1  

Jonsson  Steingrimur; Valdimarsson  Hethinn 《ICES Journal of Marine Science》2005,62(7):1350-1359

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Capelin (Mallotus villosus) distribution and climate: a sea "canary" for marine ecosystem change     

Rose  G.A. 《ICES Journal of Marine Science》2005,62(7):1524-1530

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莱西市水资源管理系统的人机互动功能     

齐勇  于诰方  李寿田  孙秀竹  胡翠红 《海洋湖沼通报》2007,(2):142-146

本文结合莱西市水资源管理的基本特性,采用人机交互管理方式,成功地运用地理信息系统(GIS),实现了界面良好的莱西市水资源信息系统的各种功能,为规范水资源业务管理的程序、开展地区水资源管理信息系统化建设,提供了有力的技术支持。  相似文献   

潮汐对瞬态气候响应模拟的影响研究     

于溢  刘海龙  林鹏飞  兰健 《海洋学报(英文版)》2020,39(1):52-62

In this study, the impact of oceanic processes on the sensitivity of transient climate change is investigated using two sets of coupled experiments with and without tidal forcing, which are termed Exp_Tide and Exp_Control,respectively. After introducing tidal forcing, the transient climate response(TCR) decreases from 2.32 K to 1.90 K,and the surface air temperature warming at high latitudes decreases by 29%. Large ocean heat uptake efficiency and heat storage can explain the low TCR in Exp_Tide. Approximately 21% more heat is stored in the ocean in Exp_Tide(1.10×10~(24) J) than in Exp_Control(0.91×10~(24) J). Most of the large ocean warming occurs in the upper 1 000 m between 60°S and 60°N, primarily in the Atlantic and Southern Oceans. This ocean warming is closely related to the Atlantic Meridional Overturning Circulation(AMOC). The initial transport at mid-and high latitudes and the decline in the AMOC observed in Exp_Tide are both larger than those observed in Exp_Control. The spatial structures of AMOC are also different with and without tidal forcing in present experiments. The AMOC in Exp_Tide has a large northward extension. We also investigated the relationship between AMOC and TCR suggested by previous studies using the present experiments.  相似文献   

Bathymetric shift in the distribution of Atlantic surfclams: response to warmer ocean temperature     

Weinberg  James R. 《ICES Journal of Marine Science》2005,62(7):1444-1453

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Pelagic fish abundance in relation to regional environmental variation in the Gulf of Finland, northern Baltic Sea     

Peltonen  Heikki; Luoto  Miska; Paakkonen  Jari-Pekka; Karjalainen  Miina; Tuomaala  Antti; Ponni  Jukka; Viitasalo  Markku 《ICES Journal of Marine Science》2007,64(3):487-495

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Physical and anthropogenic effects on observed long-term nutrient changes in the Irish Sea     

G. L. Evans  P. J. le B. Williams  E. G. Mitchelson-Jacob 《Estuarine, Coastal and Shelf Science》2003,57(5-6):1159-1168

The trend in Irish Sea nutrient concentrations over the last four decades has been considered to reflect changes in anthropogenic loading. Comparison of a long-term database for the Menai Strait, North Wales, with an established historic data set for the Cypris station, Isle of Man, indicates that climate also has a significant influence on observations of nutrient concentrations. Data are presented detailing long-term shifts in nitrate, phosphate and silicate measurements since the 1960s at these two fixed sampling sites in the Irish Sea. Broad systematic changes observed in all three nutrients over the decades show a rise from the 1960s through to the 1980s, followed generally by an overall decline in the 1990s. Decadal-scale salinity changes occur in the opposite sense to nutrient changes. Anthropogenic inputs from freshwater cannot fully account for observed nutrient trends, neither is there evidence for shifts in nutrient concentrations in oceanic waters over the past four decades. Climatically forced movement in the geographical position of the freshwater/seawater mixing zone over a decadal time scale could, however, give rise to the observed shifts in nutrient concentration and salinity. This cannot alter nutrient concentration and salinity per se, but causes the measurements taken at fixed sampling sites to fluctuate inversely over this time scale. It is concluded that there is complex interplay between anthropogenic loading and climate affecting the distribution of nutrients in the Irish Sea.  相似文献   

长江口基础生物资源现状及年际变化趋势分析   总被引：9，自引：1，他引：9  

王金辉  徐韧  秦玉涛  孙亚伟  刘材材 《中国海洋大学学报(自然科学版)》2006,36(5):821-828

探讨长江口生物资源可持续利用和对生物栖息环境的保护措施,2004年对长江口海域的基础生物资源进行4次监测。结果表明:浮游植物5月份有5门39属86种,8月份有6门48属139种,河口锋附近水域的浮游植物种类、数量较多,中肋骨条藻(Skeletonema costatum)在数量上处于绝对优势;浮游动物5月份为77种,8月份为91种,中小型浮游动物的数量在河口锋附近水域较高,主要优势种有针刺拟哲水蚤(Paracalanus aculeatus)等,大型浮游动物种类数量较高的区域位于长江冲淡水以外的海域,主要优势种为中华哲水蚤(Calanus sinicus)、五角水母(Muggiaea atlantica)、真刺唇角水蚤(Labidocera euchaeta);2004年共鉴定底栖生物146种,5月份63种,8月份108种,其中多毛类41种、甲壳类41种、软体动物32种、棘皮动物6种、鱼类21种、其他4种;长江口沿岸的崇明东滩、南汇边滩和嵊山岛共鉴定潮间带生物126种,其中5月份86种,8月份71种;鱼卵仔鱼计8目20科30属34种,鱼卵中绝大部分为凤鲚,其数量占95.7%,仔鱼以中华小公鱼出现频次最多。通过年际变化分析表明,长江口门以内区域浮游生物种类明显下降,长江冲淡水区域的生物资源基础饵料生物种类数基本保持稳定,浮游生物群落结构发生变化,硅藻比重减少,甲藻增加,长江口区域的潮下带和潮间带底栖生物种类数也存在不同程度的下降,以口门以内区域下降明显。  相似文献