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61.
Places of refuge for ships in distress is a topic before the International Maritime Organization as a result of several recent well-publicized refusals by maritime authorities of coastal states to allow such ships to enter sheltered waters within national jurisdiction. The traditional right of refuge of the crew, ship, and cargo is pitted against threat perceptions held by coastal states resulting in a "not in my backyard" syndrome. Instances of modern state practice seem to restrict the right of refuge to a purely humanitarian dimension. There is a need to reevaluate the right of refuge and to establish a system of places of refuge on the basis of regional cooperation to counter the potential threat of stricken ships that are unable to effect necessary repairs in sheltered areas within national jurisdiction.  相似文献   
62.
The United States is the sole superpower in the contemporary world and its role in the development of the law of the sea cannot be ignored. Although having not yet acceded to the U.N. Convention on the Law of the Sea, the United States has contributed to the development of the international law of the sea in numerous ways, including responding to the so-called excessive maritime claims in East Asia and creating new rules of maritime enforcement. This article assesses this recent U.S. practice.  相似文献   
63.
In March 1995, Canadian fisheries authorities boarded and arrested the Spanish fishing vessel, Estai, outside the Canadian 200‐mile zone on the Grand Banks, an event that served to focus world attention on a dispute that had its origins in the failure of the 1982 United Nations Convention on the Law of the Sea to implement an effective conservation and management regime for fish stocks on the high seas, particularly with respect to fish stocks that straddle coastal states’ exclusive economic zones. This article examines the origins of the dispute, including the allegations relating to overfishing of North Atlantic Fisheries Organization‐recommended quotas, the background to the vessel's arrest, and the subsequent confrontation that occurred, both at diplomatic levels and on the high seas, between Canada and the European Union. An analysis is made of the case in international law for Canada's extension of jurisdiction beyond 200 miles pursuant to the provisions of Section 5 of the Coastal Fisheries Protection Act. Finally, the article examines the implications of the recently concluded Agreement on the Conservation and Management of Straddling Fish Stocks and Highly Migratory Fish Stocks for disputes of the kind that arose in the present case.  相似文献   
64.
Although fossil fuels are the overwhelming source of energy for the world, and will continue to be so for the foreseeable future, demographic, environmental, political, and economic factors indicate that interest in alternative, renewable sources of energy will grow. There is a need for both global and national policies on ocean energy management. In particular, coastal states and the energy industry would benefit from guidelines that helped to create a predictable, stable environment in which long‐term, high‐cost research, development, and investment decisions could be made with confidence. Coastal states have jurisdiction over the maritime zones most relevant to energy production, but many lack the expertise and funds to develop this potential source. Industry must operate within the control of coastal states and will not be served well by a plethora of differing legal interpretations and unilaterally imposed restrictions and obligations from state to state. An Ocean Energy Protocol to the 1982 UN Convention on the Law of the Sea would afford governments and industry the opportunity to clarify their respective obligations and address particular interests for mutual benefit.  相似文献   
65.
本文将90只条件相同小鼠随机分成3组,A组服90 ppm(mg/mL)深层海水,B组服45 ppm深层海水,C组服自来水,均自由饮用30 d,第31 d时行耐缺氧实验、游泳耐力实验,断头采血,测定血细胞、肝肾功能及各种酶的变化。结果表明,在相同的饲养条件下三组体重无明显改变。A、B组比C组小鼠力竭游泳时间及耐缺氧时间显著延长(P<0.05),耗氧量显著减少(P<0.05),天冬氨酸氨基转移酶、肌酸激酶、肌酸肌酶同工酶降低,有显著差别(P<0.05),血常规、肝肾功能、电解质无显著性差异。因而,深层海水能改善酶的功能,减少小鼠的耗氧量,能明显增强小鼠的耐受力。  相似文献   
66.
Recent expeditions have revealed high levels of biodiversity in the tropical deep‐sea, yet little is known about the age or origin of this biodiversity, and large‐scale molecular studies are still few in number. In this study, we had access to the largest number of solariellid gastropods ever collected for molecular studies, including many rare and unusual taxa. We used a Bayesian chronogram of these deep‐sea gastropods (1) to test the hypothesis that deep‐water communities arose onshore, (2) to determine whether Antarctica acted as a source of diversity for deep‐water communities elsewhere and (3) to determine how factors like global climate change have affected evolution on the continental slope. We show that although fossil data suggest that solariellid gastropods likely arose in a shallow, tropical environment, interpretation of the molecular data is equivocal with respect to the origin of the group. On the other hand, the molecular data clearly show that Antarctic species sampled represent a recent invasion, rather than a relictual ancestral lineage. We also show that an abrupt period of global warming during the Palaeocene Eocene Thermal Maximum (PETM) leaves no molecular record of change in diversification rate in solariellids and that the group radiated before the PETM. Conversely, there is a substantial, although not significant increase in the rate of diversification of a major clade approximately 33.7 Mya, coinciding with a period of global cooling at the Eocene–Oligocene transition. Increased nutrients made available by contemporaneous changes to erosion, ocean circulation, tectonic events and upwelling may explain increased diversification, suggesting that food availability may have been a factor limiting exploitation of deep‐sea habitats. Tectonic events that shaped diversification in reef‐associated taxa and deep‐water squat lobsters in central Indo‐West Pacific were also probably important in the evolution of solariellids during the Oligo‐Miocene.  相似文献   
67.
Individual specialization in diet or foraging behavior within apparently generalist populations has been described for many species, especially in polar and temperate marine environments, where resource distribution is relatively predictable. It is unclear, however, whether and how increased environmental variability – and thus reduced predictability of resources – due to global climate change will affect individual specialization. We determined the within‐ and among‐individual components of the trophic niche and the within‐individual repeatability of δ13C and δ15N in feathers and red blood cells of individual female southern rockhopper penguins (Eudyptes chrysocome) across 7 years. We also investigated the effect of environmental variables (Southern Annular Mode, Southern Oscillation Index, and local sea surface temperature anomaly) on the isotopic values, as well as the link between stable isotopes and female body mass, clutch initiation dates, and total clutch mass. We observed consistent red blood cell δ13C and δ15N values within individuals among years, suggesting a moderate degree of within‐individual specialization in C and N during the prebreeding period. However, the total niche width was reduced and individual specialization not present during the premolt period. Despite significant interannual differences in isotope values of C and N and environmental conditions, none of the environmental variables were linked to stable isotope values and thus able to explain phenotypic plasticity. Furthermore, neither the within‐individual nor among‐individual effects of stable isotopes were found to be related to female body mass, clutch initiation date, or total clutch mass. In conclusion, our results emphasize that the degree of specialization within generalist populations can vary over the course of 1 year, even when being consistent within the same season across years. We were unable to confirm that environmental variability counteracts individual specialization in foraging behavior, as phenotypic plasticity in δ13C and δ15N was not linked to any of the environmental variables studied.  相似文献   
68.
Recently, methods for constructing Spatially Explicit Rarefaction (SER) curves have been introduced in the scientific literature to describe the relation between the recorded species richness and sampling effort and taking into account for the spatial autocorrelation in the data. Despite these methodological advances, the use of SERs has not become routine and ecologists continue to use rarefaction methods that are not spatially explicit. Using two study cases from Italian vegetation surveys, we demonstrate that classic rarefaction methods that do not account for spatial structure can produce inaccurate results. Furthermore, our goal in this paper is to demonstrate how SERs can overcome the problem of spatial autocorrelation in the analysis of plant or animal communities. Our analyses demonstrate that using a spatially-explicit method for constructing rarefaction curves can substantially alter estimates of relative species richness. For both analyzed data sets, we found that the rank ordering of standardized species richness estimates was reversed between the two methods. We strongly advise the use of Spatially Explicit Rarefaction methods when analyzing biodiversity: the inclusion of spatial autocorrelation into rarefaction analyses can substantially alter conclusions and change the way we might prioritize or manage nature reserves.  相似文献   
69.
为了认识南海深海冷泉区沉积物中可培养微生物的多样性,本文以冷泉区与非冷泉区两个站点的深海沉积物为样品,通过两种培养基(R2A海水培养基和2216E培养基)直接涂布或富集后平板分离纯化,从9个样品中共得到395株菌株,并通过16SrRNA基因鉴定,分属10个属。发现产芽胞细菌分布最广、丰度最大,包括3个属、15个种。其中芽胞杆菌(Bacillus)无论是在数量还是在种类上都分布最多。并且,随着水深和沉积物深度的增加,分离到的可培养微生物丰富度降低。本研究表明,即使在冷泉区,南海深海沉积物中产芽胞细菌也比较丰富。  相似文献   
70.
Traditional Mediterranean diet includes the halophyte Crithmum maritimum L. (Apiaceae) which can be found in the coastline of the Balearic Islands but also inland. Both areas differed in the environmental conditions, mainly in salinity which can affect the oxidative status of this species. The aim was to evaluate the antioxidant enzyme activities, polyphenols and the lipid peroxidation in leaves of wild C. maritimum growing in a natural coastal area influenced by marine salinity and an inland area without marine influence. The activities of the antioxidant enzymes catalase, superoxide dismutase and glutathione peroxidase as well as polyphenol and reduced glutathione content were significantly higher in the samples from coastline population, whereas no significant differences were found in glutathione reductase activity and in malondialdehyde levels. The production of H2O2 was also significantly higher in the population from coastline. In conclusion, C. maritimum adapt their antioxidant defense machinery to the different salinity conditions, avoiding the instauration of oxidative stress.  相似文献   
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