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991.
In response to recommendations made by a recent performance review, the Indian Ocean Tuna Commission (IOTC) is attempting to develop a quota allocation system (QAS) for management of the tuna and tuna-like species of the Indian Ocean. As “first-movers” in the process, Indonesia, the Seychelles, the European Union, Iran, and the Republic of Korea made contrasting proposals to the IOTC in March 2011 on possible QAS form and structure. Structure (the factors to be taken into account in determining allocation) is critical as it will determine on a long term basis the share accruing to each IOTC member state of the estimated USD 2-3 billion worth of tuna caught in the Indian Ocean each year. This article records and discusses the content of these first steps towards QAS formulation by placing them in the context of rights-based management as applied to the offshore areas falling under tuna RFMO management. The options proposed in March (which the IOTC is still considering) all have a similar architecture but result in sharply divergent allocation outcomes. Despite the sophistication of some of the proposals, the recent IOTC review suggests that the regulatory and management capacity of the IOTC does not match the science and enforcement requirements appropriate to these recent proposals. Perhaps efforts to improve IOTC performance need to be made in parallel with discussions on QAS definition and implementation. To further advance the debate and also concretely demonstrate likely economic outcomes, the article provides indicative monetary valuations of quota allocations proposed. It uses a range of potential historical reference periods (5, 10, 15, and 20 years).  相似文献   
992.
From 2009 to 2011, marine spatial planning (MSP) rapidly gained visibility in the United States as a promising ocean management tool. A few small-scale planning efforts were completed in state waters, and the Obama Administration proposed a framework for large-scale regional MSP throughout the U.S. Exclusive Economic Zone. During that same time period, the authors engaged a variety of U.S ocean stakeholders in a series of dialogs with several goals: to share information about what MSP is or could be, to hear stakeholder views and concerns about MSP, and to foster better understanding between those who depend on ocean resources for their livelihood and ocean conservation advocates. The stakeholder meetings were supplemented with several rounds of in-depth interviews and a survey. Despite some predictable areas of conflict, project participants agreed on a number of issues related to stakeholder engagement in MSP: all felt strongly that government planners need to engage outsiders earlier, more often, more meaningfully, and through an open and transparent process. Equally important, the project affirmed the value of bringing unlike parties together at the earliest opportunity to learn, talk, and listen to others with whom they rarely engage.  相似文献   
993.
王为术  闫广  李帅帅 《海洋科学》2012,36(10):68-72
盐水闪蒸技术广泛应用于海水淡化及海洋温差能发电,含盐质量分数、给盐液温度和闪蒸压力对闪蒸汽化率和热效率有很大影响。在质量分数为3.5%~20%、给盐液温度为30~95℃和闪蒸压力为1~30 kPa的范围内,对NaCl溶液闪蒸汽化率和热效率等闪蒸效率特性进行了定量计算研究,研究得到了盐水含盐质量分数、给盐液温度和闪蒸压力对闪蒸汽化率以及热效率影响的规律。结果表明,降低含盐质量分数,提高给盐液温度,降低闪蒸压力可提高闪蒸汽化率与热效率;含盐质量分数越高,造成的热损失越大,而提高给盐液温度会增大热损失。  相似文献   
994.
西北冰洋表层沉积物中重金属的赋存形态研究   总被引:1,自引:0,他引:1  
用连续提取法对选自西北冰洋的32个表层沉积物进行分析,测定了Cr、Cu、Pb在全样中及其在P1-2、P3、P4、P5中的含量.结果表明随着离岸距离增加,水深加深,Cr、Cu、Pb含量呈增高的趋势.研究区陆架沉积物中Cr、Cu、Pb含量分别为60.66、14.77、16.65μg/g;深海沉积物中Cr、Cu、Pb的含量分别为80.40、41.70、25.62μg/g.元素赋存形态分析表明,Cr、Cu、Pb主要赋存在残渣态,残渣态中三元素的含量平均值分别为64.97、19.67、17.56μg/g,占元素总量的比例分别为93.58%、75.02%和83.76%.三元素在各赋存形态中的含量分布是:Cu为残渣态>有机质和硫化物态>铁锰氧化态>可交换及碳酸盐态;Pb和Cr则为残渣态>铁锰氧化物态>有机质硫化物态>可交换态及碳酸盐态.研究区重金属元素在不同赋存形态中的含量分布与北太平洋深海沉积物中类似.  相似文献   
995.
1949—2009年登陆和影响浙江的热带气旋分析   总被引:1,自引:0,他引:1  
朱业  丁骏  卢美  王晶  王勤 《海洋预报》2012,29(2):8-13
通过对1949—2009年61年间登陆和影响浙江的热带气旋的时空分布特征、主要影响路径等的分析,发现在7—9月份登陆浙江的热带气旋占登陆总数的92.5%,7—9月份影响浙江的热带气旋占影响总数的82%。影响浙江的热带气旋中登陆福建或在台湾海峡消失的热带气旋占的比重最多。虽然西北太平洋上热带气旋生成个数近年来大幅减少,但登陆浙江的强台风有明显增多的趋势。随着气候的变暖,海水温度的增高,热带气旋生成的时间提早,结束的时间偏迟。另外通过对热带气旋影响时各海岛、沿海和内陆站的大风、暴雨的分析,发现热带气旋影响期间容易引起大风天气的是大陈和嵊山站;容易引起暴雨天气的是温岭、临海和温州站。本文还分析了验潮站最大增水超过1m、2m、3m的时空分布特征。  相似文献   
996.
The trophic role of the hyperiid amphipod Themisto gaudichaudii in the southern Patagonian shelf food web was assessed from the analysis of stomach contents of the local fish assemblage. A total of 461 trawl samples were collected during seven seasonal cruises. A total of 17 out of 38 fish species were found to ingest T. gaudichaudii. This amphipod was a main prey item in five of these species, showing high values of alimentary index: Seriolella porosa (99.9%), Macruronus magellanicus (68.8%), Micromesistius australis (59.1%), Patagonotothen ramsayi (48.6%), and Merluccius hubbsi (10.9%). The contribution of T. gaudichaudii, in weight, to their summer diet was 60%, on average. This contribution was minimal in winter and maximal in summer. Fisheries studies have indicated that these five species, mainly M. magellanicus, account for almost 85% of the fish biomass in the area. Although the remaining 15% did not feed heavily on T. gaudichaudii, they are known to prey on the main hyperiid predators. Our study shows that T. gaudichaudii contributes greatly, both directly and indirectly, to supporting the fish community. We thus proposed that T. gaudichaudii plays a key role as a “wasp-waist” species in the sub-Antarctic region, similar to that of krill in Antarctic waters, channeling the energy flow and enabling a short and efficient food chain.  相似文献   
997.
西南印度洋中脊是典型的慢速扩张洋中脊之一。对采自西南印度洋中脊50°E附近的7件玄武岩和蛇纹石化橄榄岩样品所作的分析表明,基性玄武岩类SiO2含量为43.72%~48.40%,TiO2含量较少,为1.14%~1.52%;MgO含量为5.96%~10.98%;TFe2O3含量为4.55%~5.2%;Mg#值为0.53~0.64,里特曼指数σ为2.34~20.10。微量元素Zr/Nb和Y/Nb比值为显示N-MORB的性质,但是其他微量元素的比值(Ba/Nb,Ba/Th,La/Nb,Nb/U,Nb/Pb)均不显示正常洋中脊玄武岩的特征,微量元素原始地幔标准化蛛网图显示强烈富集K和Pb,亏损Nb,稀土元素显示较为平缓的分配模式。超基性蛇纹石化橄榄岩的主量元素特征为SiO2为38.91~45.49;TiO2含量为0.02~0.28;MgO含量很高,为36.87~40.61,TFe2O3含量为2.82~3.91,Mg#值为0.92~0.94。微量元素中Ni,Cr的含量很高,原始地幔标准化蛛网图显示橄榄岩强烈富集K和Pb,Ba,Th,La,Ce,Ti中等程度富集,而亏损Nb,Sr。稀土元素总量较低,标准化曲线显示轻稀土元素富集模式。结合地球化学特征及前人研究资料分析认为,西南印度洋中脊的基性岩和超基性岩属同源性质,其原始地幔物质可能为部分正常洋中脊亏损地幔混染了陆壳或远洋沉积物的结果。  相似文献   
998.
Picophytoplankton are responsible for much of the carbon fixation process in the Arctic Ocean, and they play an im- portant role in active microbial food webs. The climate of the Arctic Ocean has changed in recent years, and picophytoplankton, as the most vulnerable part of the high-latitude pelagic ecosystem, have been the focus of an increasing number of scientific studies. This paper reviews and summarizes research on the characteristics of picophytoplankton in the Arctic Ocean, including their abundance, biomass, spatial distribution, seasonal variation, commtmity structure, and factors influencing their growth. The impact of climate change on the Arctic Ocean picophytoplankton community is discussed, and future research directions are considered.  相似文献   
999.
西北太平洋(含南海)热带气旋路径集成预报分析   总被引:2,自引:1,他引:1  
基于2004—2009 年中国中央气象台、日本气象厅、美国联合台风警报中心、欧洲中心对西北太平洋和南海编号热带气旋主客观预报资料,利用算术平均、多元回归以及历史平均误差等三种集成方法,建立了热带气旋路径集成预报业务化系统。通过2007—2009 年的业务运行结果分析发现,欧洲中心客观预报参与的24、48 和72 h 集成比主观预报三个成员集成预报水平分别提高约2%、3%~5%和3%~5%,减小误差2.5 km左右、6~9 km 和10~12 km。技巧分析发现,24~72 h 集成预报有正技巧,多元回归集成技巧相对稍低,而算术平均和以各成员平均误差的平方倒数为权重系数的集成技巧对于各集成成员来说技巧差异不大。96 h 集成预报对欧洲中心的客观预报没有正技巧。   相似文献   
1000.
Standard data and methods, such as the inversion of seismic and GPS data, have been used extensively to infer the details of the 2004 December 26 earthquake. The unprecedented large size of this event gave the opportunity to modern altimeters to provide the first clear records of a tsunami in deep ocean, therefore allowing us to study the rupture history from an independent perspective. We invert the Jason-1 and Topex–Poseidon altimetry records, considering the new constraints available on the geometry of the fault plane, and taking them into account in a 3-D rupture model. The data are corrected for the non-negligible effect of satellite motion during measurements. Our results show that the rupture propagated over the 1500 km of subduction zone initially identified by the aftershock distribution, with a magnitude of   M w= 9.1  . Our solution compares well with the latitudinal distribution of slip inferred from other data sets, with a maximum of energy release north of Sumatra, and two other slip patches near the Nicobar and Andaman islands. Based on waveform comparison, we assert that the shallow portion of the megathrust offshore Banda Aceh had slip amplitudes of more than 20 m. Also, we find that significant amounts of slip (about 10 m) concentrated below the Andaman islands and did not propagate on the shallow portion of the interface. Although synthetic tests tend to show less resolution in the northern part of the rupture, this solution is compatible with the near-field data (GPS, coral heads and imagery), and would allow one to explain the apparent paradox between the large local displacements and the moderate tsunami observed locally. Finally, we demonstrate the rapidly dominating effect of propagation and slip distribution over the rupture velocity, and how it precludes the direct estimate of this latter parameter.  相似文献   
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