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1.
Abstract

The U.N. Law of the Sea Convention, ambiguous on military uses of the ocean space, weakens the legal basis for the maritime powers to pursue freely their military objectives in the oceans. Repudiation of the Convention by the United States will accelerate the creeping jurisdiction of the littoral states. The Convention enhances the security of the littoral states of the Indian Ocean, all of whom have only limited blue‐water capabilities and have sought to contain the military intrusions of the superpowers into the Indian Ocean.  相似文献   

2.
On May 25, 2005, Ireland lodged the first example of a so-called “partial submission” to the Commission on the Limits of the Continental Shelf in respect of an allegedly “undisputed” area of seabed beyond 200 nm limits sandwiched between disputed and extensive seabed claims to the north (Hatton-Rockall Area) by Denmark/Faroes and Iceland, and an as yet undelimited seabed area to the south (the Celtic Shelf) where the United Kingdom, France, and Spain may also have seabed claims. This article considers the problems that may arise even from this supposedly uncontroversial type of submission in the light of the diplomatic reaction by both Denmark/Faroes and Iceland in August 2005.  相似文献   

3.
To face the climate crisis, sustainable energy harvesting systems are critical. Triboelectric nanogenerators (TENGs) are in the spotlight for their inexpensive and non-toxic manufacturing, allied with their excellence in harvesting low frequency vibrations. Ocean waves are a prime example of energy source in this regime, and their successful harvesting with TENGs has been widely demonstrated. However, the influence of wave characteristics on the power output of these devices has so far been overlooked. Here, the existence of a moving element that acts upon the nanogenerators is explored both with multiphysics simulations and an extensive experimental characterization under different operating conditions. It is shown how different sea states modulate the moving body velocity, and how the generator can be optimized to harvest waves with specific characteristics. In parallel, it is demonstrated that the power output is proportional to the contacting triboelectric layers velocity. Optimizing the dynamics of the moving body provides an efficient path to intentionally tune the contacting triboelectric layers velocity, and therefore improve the output of TENGs and their suitability to harvest specific sea states.  相似文献   

4.
This article recounts the negotiations and emergence of Article 234 concerning ice-covered areas in the UN Convention on the Law of the Sea. As Arctic shipping increases, more vessels and flag states may be subject to the provisions of Article 234, which permit coastal states to both prescribe and enforce special measures to protect the marine environment in ice-covered areas. The history of the Article 234, disclosed partially through declassified U.S. government documents, provides context for implementation of the provision by Arctic coastal states and flag states.  相似文献   

5.
Ocean warming (OW) and acidification (OA) are intensively investigated as they pose major threats to marine organism. However, little effort is dedicated to another collateral climate change stressor, the increased frequency, and intensity of storm events, here referred to as intensified hydrodynamics. A 2‐month experiment was performed to identify how OW and OA (temperature: 21°C; pHT: 7.7, 7.4; control: 17°C‐pHT7.9) affect the resistance to hydrodynamics in the sea urchin Paracentrotus lividus using an integrative approach that includes physiology, biomechanics, and behavior. Biomechanics was studied under both no‐flow condition at the tube foot (TF) scale and flow condition at the individual scale. For the former, TF disk adhesive properties (attachment strength, tenacity) and TF stem mechanical properties (breaking force, extensibility, tensile strength, stiffness, toughness) were evaluated. For the latter, resistance to flow was addressed as the flow velocity at which individuals detached. Under near‐ and far‐future OW and OA, individuals fully balanced their acid‐base status, but skeletal growth was halved. TF adhesive properties were not affected by treatments. Compared to the control, mechanical properties were in general improved under pHT7.7 while in the extreme treatment (21°C‐pHT7.4) breaking force was diminished. Three behavioral strategies were implemented by sea urchins and acted together to cope with flow: improving TF attachment, streamlining, and escaping. Behavioral responses varied according to treatment and flow velocity. For instance, individuals at 21°C‐pHT7.4 increased the density of attached TF at slow flows or controlled TF detachment at fast flows to compensate for weakened TF mechanical properties. They also showed an absence of streamlining favoring an escaping behavior as they ventured in a riskier faster movement at slow flows. At faster flows, the effects of OW and OA were detrimental causing earlier dislodgment. These plastic behaviors reflect a potential scope for acclimation in the field, where this species already experiences diel temperature and pH fluctuations.  相似文献   

6.
Little is known about the processes regulating species richness in deep‐sea communities. Here we take advantage of natural experiments involving climate change to test whether predictions of the species–energy hypothesis hold in the deep sea. In addition, we test for the relationship between temperature and species richness predicted by a recent model based on biochemical kinetics of metabolism. Using the deep‐sea fossil record of benthic foraminifera and statistical meta‐analyses of temperature‐richness and productivity‐richness relationships in 10 deep‐sea cores, we show that temperature but not productivity is a significant predictor of species richness over the past c. 130 000 years. Our results not only show that the temperature‐richness relationship in the deep‐sea is remarkably similar to that found in terrestrial and shallow marine habitats, but also that species richness tracks temperature change over geological time, at least on scales of c. 100 000 years. Thus, predicting biotic response to global climate change in the deep sea would require better understanding of how temperature regulates the occurrences and geographical ranges of species.  相似文献   

7.
This article explores the relationship between Vietnam's national interests and the international law of the sea. Vietnam's national interests in the marine sphere include defense (the maintenance of a maritime buffer); international relations (enhancing its regional position through joint development and favorable resolution of boundary and fisheries disputes); and economics (stimulating development of its maritime resources). Although ratification of the 1982 Law of the Sea Convention would be somewhat disadvantageous to Vietnam's maritime defense strategy, many provisions would promote Vietnam's interests. Moreover, ratification and implementation of the Convention would signal Vietnam's support for international law and its desire to “rejoin”; the community of Southeast Asian nations. It might also encourage resolution of its boundary disputes, thus opening new areas to resource exploration and development by foreign companies.  相似文献   

8.
Climate change driven ocean warming and acidification is potentially detrimental to the sensitive planktonic life stages of benthic marine invertebrates. Research has focused on the effects of acidification on calcifying larvae with a paucity of data on species with alternate developmental strategies and on the interactive effects of warming and acidification. To determine the impact of climate change on a conspicuous component of the intertidal fauna of southeast Australia, the development of the noncalcifying lecithotrophic larvae of the sea star Meridiastra calcar was investigated in the setting of predicted ocean warming (+2 to 4 °C) and acidification (?0.4 to 0.6 pH units) for 2100 and beyond in all combinations of stressors. Temperature and pH were monitored in the habitat of M. calcar to place experiments in context with current environmental conditions. There was no effect of temperature or pH on cleavage stage embryos but later development (gastrula‐larvae) was negatively effected by a +2 to 4 °C warming and there was a negative effect of ?0.6 pH units on embryos reaching the hatched gastrula stage. Mortality and abnormal development in larvae increased significantly even with +2 °C warming and larval growth was impaired at +4 °C. For the range of temperature and pH conditions tested, there were no interactive effects of stressors across all stages monitored. For M. calcar, warming not acidification was the dominant stressor. A regression model incorporating data from this study and projected increasing SST for the region suggests an increase in larval mortality to 70% for M. calcar by 2100 in the absence of acclimation and adaptation. The broad distribution of this species in eastern Australia encompassing subtropical to cold temperate thermal regimes provides the possibility that local M. calcar populations may be sustained in a warming world through poleward migration of thermotolerant propagules, facilitated by the strong southward flow of the East Australian Current.  相似文献   

9.
High seas oceanic ecosystems are considered important habitat for juvenile sea turtles, yet much remains cryptic about this important life‐history period. Recent progress on climate and fishery impacts in these so‐called lost years is promising, but the developmental biogeography of hawksbill sea turtles (Eretmochelys imbricata) has not been widely described in the Pacific Ocean. This knowledge gap limits the effectiveness of conservation management for this globally endangered species. We address this with 30 years of stranding observations, 20 years of bycatch records, and recent simulations of natal dispersal trajectories in the Hawaiian Archipelago. We synthesize the analyses of these data in the context of direct empirical observations, anecdotal sightings, and historical commercial harvests from the insular Pacific. We find hawksbills 0–4 years of age, measuring 8–34 cm straight carapace length, are found predominantly in the coastal pelagic waters of Hawaii. Unlike other species, we find no direct evidence of a prolonged presence in oceanic habitats, yet satellite tracks of passive drifters (simulating natal dispersal) and our small sample sizes suggest that an oceanic phase for hawksbills cannot be dismissed. Importantly, despite over 600 million hooks deployed and nearly 6000 turtle interactions, longline fisheries have never recorded a single hawksbill take. We address whether the patterns we observe are due to population size and gear selectivity. Although most sea turtle species demonstrate clear patterns of oceanic development, hawksbills in the North Pacific may by contrast occupy a variety of ecosystems including coastal pelagic waters and shallow reefs in remote atolls. This focuses attention on hazards in these ecosystems – entanglement and ingestion of marine debris – and perhaps away from longline bycatch and decadal climate regimes that affect sea turtle development in oceanic regions.  相似文献   

10.
The inaccessibility of open ocean habitat and the cryptic nature of small animals are fundamental problems when assessing the distribution of oceanic-stage sea turtles and other marine animals sharing similar life-history traits. Most methods that estimate patterns of abundance cannot be applied in situations that are extremely data limited. Here, we use a movement ecology framework to generate the first predicted distributions for the oceanic stage of the Kemp''s ridley sea turtle (Lepidochelys kempii). Our simulations of particle dispersal within ocean circulation models reveal substantial annual variation in distribution and survival among simulated cohorts. Such techniques can help prioritize areas for conservation, and supply inputs for more realistic demographic models attempting to characterize population trends.  相似文献   

11.
Submarine communications cables laid on the seabed of the ocean are the foundation of the world's international telecommunications network. International law, in particular, the law of the sea, has recognized the freedom to lay submarine cables and perform associated operations and has placed certain obligations on states related to the protection of submarine cables. This article examines the international law with respect to submarine cables and discusses the various problems with both the law and state practice on submarine cables. It argues that these problems are illustrations of the traditional challenges that face the law of the sea; that is, the balancing and accommodation of competing uses of ocean space. It concludes that an important step toward resolving these problems is enhanced consultation and cooperation between cable companies and governments and that efforts should focus on creating such mechanisms.  相似文献   

12.
Conciliation is an age-old peaceful means of dispute settlement. The UN Convention on the Law of the Sea provides for both voluntary and compulsory conciliation. The importance of conciliation under UNCLOS is obvious, yet it has received little focused attention.  相似文献   

13.
Problems resulting from contemporary patterns of ocean use and threats to the viability of the marine environment have led to reconsideration of ocean use governance in a number of states, including the United States, Australia, and Canada. For its part, the European Union has been working on the development of a Marine Strategy to safeguard the environment and a more encompassing Maritime Policy into which the Marine Strategy would be folded. The desired Maritime Policy would reflect a holistic perspective of ocean space, embody an ecosystem-based approach to ocean use management, and provide a broad framework for ocean/coastal management. As has been seen elsewhere, developing such a governance system is difficult both in terms of conceptualization and, subsequently, in operationalization. The June 2006 European Commission Green Paper on Maritime Policy sets the stage for a year of consultations designed to develop an effective governance system for ocean management. Institutional and policy changes will be needed and it will be necessary to balance the objectives of economic growth and protection of environmental sustainability. This article examines current developments in efforts to devise a coherent and integrated European Union approach to ocean management.  相似文献   

14.
Abstract

Coastal state enforcement in new zones of jurisdiction under the ocean management regime envisaged in the Law of the Sea Conference's negotiating text will undoubtedly spawn new technology in an effort to expand and improve surveillance. The author discusses enforcement challenges presented in the Law of the Sea regime and suggests some possible applications of technology to improve maritime law enforcement in the relatively near future.  相似文献   

15.
The increase of anthropogenic CO2 during this century is expected to cause warming of large regions of the ocean. Microbes lead the biological role in the CO2 balance of marine ecosystems, their activity is known to be influenced by temperature, and it is important to constrain and quantify these effects on bacterial carbon use. Furthermore, if warming were to enhance the carbon demand (production + respiration) of planktonic microbes but would maintain their efficiency low (as it generally is), then most carbon consumed would end up respired. We designed a strategy in which we measured bacterial production and respiration throughout a seasonal cycle in a coastal Mediterranean site, and determined experimentally the effects of ca. 2.5 °C on these processes. We show that warming will increase nearly 20% the total carbon demand of coastal microbial plankton without any effect on their (commonly low) growth efficiency, which could generate a positive feedback between coastal warming and CO2 production.  相似文献   

16.
Co‐occurring ocean warming, acidification and reduced carbonate mineral saturation have significant impacts on marine biota, especially calcifying organisms. The effects of these stressors on development and calcification in newly metamorphosed juveniles (ca. 0.5 mm test diameter) of the intertidal sea urchin Heliocidaris erythrogramma, an ecologically important species in temperate Australia, were investigated in context with present and projected future conditions. Habitat temperature and pH/pCO2 were documented to place experiments in a biologically and ecologically relevant context. These parameters fluctuated diurnally up to 10 °C and 0.45 pH units. The juveniles were exposed to three temperature (21, 23 and 25 °C) and four pH (8.1, 7.8, 7.6 and 7.4) treatments in all combinations, representing ambient sea surface conditions (21 °C, pH 8.1; pCO2 397; ΩCa 4.7; ΩAr 3.1), near‐future projected change (+2–4 °C, ?0.3–0.5 pH units; pCO2 400–1820; ΩCa 5.0–1.6; ΩAr 3.3–1.1), and extreme conditions experienced at low tide (+4 °C, ?0.3–0.7 pH units; pCO2 2850–2967; ΩCa 1.1–1.0; ΩAr 0.7–0.6). The lowest pH treatment (pH 7.4) was used to assess tolerance levels. Juvenile survival and test growth were resilient to current and near‐future warming and acidification. Spine development, however, was negatively affected by near‐future increased temperature (+2–4 °C) and extreme acidification (pH 7.4), with a complex interaction between stressors. Near‐future warming was the more significant stressor. Spine tips were dissolved in the pH 7.4 treatments. Adaptation to fluctuating temperature‐pH conditions in the intertidal may convey resilience to juvenile H. erythrogramma to changing ocean conditions, however, ocean warming and acidification may shift baseline intertidal temperature and pH/pCO2 to levels that exceed tolerance limits.  相似文献   

17.
Pacific sleeper sharks Somniosus pacificus were captured near Steller sea lion Eumetopias jubatus rookeries during the period when Steller sea lion pups are most vulnerable to Pacific sleeper shark predation (first water entrance and weaning). Analysis of stomach contents revealed that teleosts were the dominant prey in August and cephalopods were the dominant prey in May ( n = 198). Marine mammals were found in 15% of stomachs regardless of season, but no Steller sea lion tissues were detected. Molecular genetic analysis identified grey whale Eschrichtius robustus and harbour seal Phoca vitulina remains in some Pacific sleeper shark stomachs. Most mammals were cetacean and at least 70% of the cetaceans were probably scavenged. Although Pacific sleeper shark and Steller sea lion ranges overlapped, so predation could potentially occur, the diet study suggested that predation on Steller sea lions is unlikely, at least when pups first enter the water or during weaning. Harbour seals were infrequent prey and may have been consumed alive. Pacific sleeper sharks consume fast-swimming prey like Pacific salmon Oncorhynchus sp., most likely live animals rather than scavenged animals. Pacific sleeper sharks appeared to be opportunistic consumers of the available prey and carrion, feeding both on the bottom and in the water column, and their diet shifted to teleosts and cetacean carrion as the fish grew larger.  相似文献   

18.
19.
袁秀堂  杨红生  王丽丽  周毅  张涛  刘鹰 《生态学报》2007,27(8):3155-3161
夏眠是刺参最重要的生理特征;水温升高是其夏眠的主要诱发因子,而夏眠的临界温度与刺参体重密切相关。为揭示刺参夏眠对其能量利用对策的影响,测定了2种体重规格(134.0±13.5)g和(73.6±2.2)g刺参在10、15、20、25℃和30℃5个温度梯度下的能量收支。结果表明,温度和体重及其交互作用对刺参能量的摄入均有显著影响;而温度是影响其摄食能分配的主要因素。研究发现,刺参在非夏眠期、夏眠临界期和完全夏眠期的能量利用对策有所不同:在非夏眠期,刺参摄食能支出的最大组分是粪便能,占摄食能的比例超过50%,其次为呼吸耗能,占19.8%~39.4%,而生长能和排泄能占的比例较小,分别为5.7%~10.7%和2.9%~3.7%;在夏眠临界温度下,呼吸和排泄耗能占摄食能的比例均显著增大(分别为88.3%和13.6%),而生长能所占比例降为负值(-55.3%),刺参表现为负生长;而在夏眠期,刺参的摄食能和排粪能为零,为维持其基本生理活动,不得不动用以往贮存于体内的能量,消耗于呼吸和排泄等生理过程,供维持生命之用。总之,从能量生物学的角度看,夏眠的主要生态学意义在于刺参长时间处于相对高温环境,进而导致摄食受阻条件下的一种能量节约方式。  相似文献   

20.
Yuan X T  Yang H S  Wang L L  Zhou Y  Zhang T  Liu Y 《农业工程》2007,27(8):3155-3161
Apostichopus japonicus is a kind of temperate sea cucumbers, known to aestivate when water temperature rises above 20°C to 24.5°C. In this study, we measured the effects of aestivation on the energy utilization (i.e., energy allocation in growth, feces discharge, respiration and excretion) of A. japonicus with two different body weights (134.0 g ± 3.5 g and 73.6 g ± 2.2 g) at water temperature from 10°C to 30°C with an interval of 5°C. Noticeable variation in the energy utilization of sea cucumbers was observed in this study. During the non-aestivation period, energy deposit in growth was lower and the energy loss in feces accounted for the majority of the feeding energy. Under the threshold temperature, the feeding energy reduced and the proportion of energy deposit in growth became negative. During aestivation, sea cucumbers discontinued feeding energy, resulting in weight loss. Our study suggested that the ecological implication of aestivation in this species could lead to a model of energy saving during the long-term hot period.  相似文献   

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