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1.
Persistent organic pollutants such as Polychlorinated biphenyls (PCB) and dichloro diphenyl trichloroethane (DDT) are known to exert various adverse health effects in wildlife mammals. The impact from dietary intake of minke whale (Balaenoptera acutorostrata) blubber high in organohalogen and other chemical contaminants on renal morphology and function was investigated via a controlled study on West Greenland sledge dogs (Canis familiaris). Our results showed significantly higher frequencies of glomerular, tubular, and interstitial lesions in the exposed group. Furthermore, higher urine protein?:?creatinine ratio and plasma urea levels were found in the exposed group, which indicated a negative impact on kidney function via tubular and glomerular dysfunctions. The lesions were similar to those observed in top predator marine species–such as seals and polar bears–and humans exposed via diet to persistent environmental pollutants. The lesions may have impacts on the overall health of these animals. It is reasonable to suggest that chronic exposure to organic pollutants via a country diet of high trophic level marine organisms may have an impact on renal morphology and function in Arctic apex predators in general as well as Inuit people.  相似文献   

2.
The Greenland shark (Somniosus microcephalus) is the only shark species known to inhabit ice-covered seas in the North Atlantic, but remains a missing component in most studies of Arctic food webs. In the present study, stable isotopes (SIs) of nitrogen (δ15N) and carbon (δ13C) and fatty acids (FAs) were analyzed to identify the role of Greenland sharks (sampled during June 2008–2009) in Kongsfjorden, a productive fjord on the west coast of Svalbard, Norway (~79ºN, 12–13ºE). The Greenland shark fed at a high trophic position (4.8) based on δ15N values, and δ13C confirmed that most (70 %) of their carbon was derived from phytoplankton-based food chains, which is consistent with a heavy reliance on pelagic teleosts and seals. Greenland sharks from Kongsfjorden had fatty acid profiles in both muscle and plasma (e.g., low 20:1n-9, high 22:5n-3) that suggested a low portion of Greenland halibut (Reinhardtius hippoglossoides) and high proportion of gadoids and seals in their diet compared to Greenland sharks sampled in Cumberland Sound, Canada, during April 2008, which were previously shown to derive much of their energy from Greenland halibut. The high proportions of seal fatty acids in both slow- (muscle) and fast- (plasma) turnover tissues indicate that trophic interactions between Greenland sharks and seals in Kongsfjorden are a common occurrence. Results from the present study suggest that Greenland sharks likely play a unique and significant role in Arctic marine food webs as a top predator of fishes and marine mammals.  相似文献   

3.
There is a general lack of knowledge as regards the effects of climate change on pollutant behavior. This is particularly true of the Asia-Pacific Region (APR). This region has major significance in terms of global pollutant emission and also displays a wide variety of environments. This review presents the authors’ opinions on possible implications of climate change for pollutant behavior in the APR. Although differing responses can be expected across the region, there are clear implications as regards the short- and long-term behavior of pollutants. Effects can be predicted through modeling, but further data are required for model calibration. Nevertheless, it can be predicted that climate change will affect processes including global distillation of persistent organic pollutants, airborne transport of heavy metals, half-life of readily degradable pollutants, and eutrophication in water bodies. Particulates are expected to play a central role in mediating the effects of climate change, and successful predictive models will need to be based on particulate-mediated transport and behavior. Climate change also has the potential to cause an increase in the intensity and frequency of harmful algal blooms in aquatic environments throughout the region, with significant implications for supply of both food and drinking water.  相似文献   

4.
IP25 is a highly branched isoprenoid and an organic geochemical biomarker that is produced by some Arctic sea ice diatoms. IP25 has previously been used in Arctic palaeo sea ice reconstruction studies and as a tracer for studying Arctic food webs. Here, the molecular structure of IP25 has been confirmed by 1H and 13C NMR spectroscopy following large-scale extraction from marine sediments obtained from the Canadian Arctic and purification using a combination of open-column and HPLC chromatographic methods. The structure of IP25 was consistent between the three different sampling locations and was identical to that found previously for this biomarker following synthesis from a closely related highly branched isoprenoid diene. Since this study represents the first structural characterisation of IP25 in sediments, future analysis of sedimentary IP25 for palaeo Arctic sea ice reconstructions can be carried out with much greater confidence.  相似文献   

5.
6.
短链氯化石蜡(SCCPs)是碳链长度为10至13个碳原子的正构烷烃氯代衍生物。SCCPs具有持久性、生物累积性、长距离迁移能力、以及毒性作用。SCCPs已被《关于持久性有机污染物的斯德哥尔摩公约》增列为持久性有机污染物审查范围内,引起了全球关注。SCCPs在环境各介质及生物体内均有检出,近年来,在室内空气和灰尘中也检出了大量SCCPs,其已成为人体暴露的一个重要来源。本文就大气环境及室内空气与灰尘中氯化石蜡(CPs)的采样与分析方法、污染水平与来源,及人体暴露概况进行了综合阐释,以期为我国大气和室内环境中CPs的研究工作提供参考。  相似文献   

7.
Summary The social dynamics of killer whales (Orcinus orca) that hunt marine mammals are apparently highly flexible, though strong individual associations do exist. The killer whales at Punta Norte offer an unusually detailed view of association patterns and foraging behaviour, and suggest a pattern of behaviour that optimizes hunting efficiency with exception only to strong associations between some individuals and the provisioning and training of offspring. The main points from this paper are as follows: First, hunting effort was concentrated where the capture rate was greatest. All pods selectively attacked the prey type for which they had the highest capture rate. The amount of southern sea lion prey captured was approximately equal to the estimated minimum energetic requirement for killer whales based on weight. Secondly, one whale in each pod did the majority of the hunting, and then provisioned the others in the pod. It was clear on numerous occasions that food was shared. A review of reported incidences of killer wales taking marine mammal prey suggests that it is common for a subset of the individuals in a pod to hunt. These results are discussed in the context of the evolution of foraging behaviour.Offprint requests to: A.R. Hoelzel at the first address  相似文献   

8.
There are two approaches in the application of satellite sensors to marine pollution studies. Satellite sensors are used to observe and characterize ocean pollutants such as industrial wastes and oil. in addition, satellite observations provide information useful in illuminating processes such as eutrophi-cation or air-sea exchange of CO2, that are important in determining the distribution and fate of pollutants.

Satellite technology is an important tool in monitoring and studying ocean pollution. Visible sensors have been used to observe and characterize sewage sludge and industrial wastes dumped at sea. Oil slicks have been observed with Landsat, AVHRR and SAR imagery. Besides directly detecting pollutants, satellite sensors are useful for analyzing ocean processes that are influential in the fate of pollutants. These processes include eutrophication of coastal waters and the distribution of suspended matter. the fate of excess CO2 can be addressed using scatterometer-derived estimates of wind speeds to determine the CO2 exchange coefficient at the sea surface on a global scale.  相似文献   

9.
Background, aim, and scope The marine environment is often the final sink for pollutants, especially for persistent organic pollutants (POPs) and for persistent, bioaccumulative and toxic (PBT) substances. The body burden of marine top predators in the Baltic Sea, in the North Sea and also in the Arctic seas is alarming. Thus, the question was investigated if the European environmental law considers a prospective marine ecological risk assessment of chemicals, pesticides and dredged material before they are launched on the market or disposed to the sea. Results The analysis of European environmental law showed that the European environmental protection goals demand a good quality status of coastal waters until 2015 (Waterframework Directive) and a good quality status of European seas until 2020 (Marine Strategy Directive), but a specific marine ecological risk assessment of chemicals and pesticides is not sufficiently required in current European legislation. Discussion It was shown that the ecological risk assessment for freshwater ecosystems is, due to the pecularities of pollutant impacts in the marine environment, not adequate to predict marine effects and to protect the marine environment sufficiently. A statistical analysis of international databases on the relative toxicity of narcotics revealed that marine organisms can be significantly more sensitive than freshwater organisms towards substances with an unspecific mode of action (narcotics). Approximately 60?% of the industrial chemicals are classified as narcotics by their mode of action. Thus, this substance class is of environmental importance. Due to the hydrophobic properties and the low solubility of narcotics in seawater, the ecotoxicological assessment of marine sediments was of interest. An estuarine and marine bioassay test set was established and further developed to assess the ecotoxicological potential of brackish and seawater sediments. It was important that the test procedures were adapted to brackish and marine conditions and were harmonised between each other as well as on the international level. Conclusions Beside two bioassays for the ecotoxicological assessment of elutriates of marine and brackish sediments (bacteria bioluminescence test and marine algae test), the implementation and further development of the whole sediment bioassay with the marine amphipod Corophium volutator was important for enhancing the risk assessment. In order to gain a more standardised, all-season available test organism, the marine amphipod was for the first time reproduced under laboratory conditions the whole year round (also in winter), which is the essential basis for the urgently needed chronic whole sediment bioassay. The results of this investigation were implemented in the international (ISO), European (EN) and national (DIN) standardisations. Therefore, a standardised test set is ready for the implementation in the marine ecological risk assessment of chemicals, pesticides and dredged material in international, European and national legislation. Recommendations and perspectives Recommendations to improve the implementation of a marine risk assessment in European regulations are given with the goal to reach the internationally required objective of a sustainable development of the seas.  相似文献   

10.
There are two approaches in the application of satellite sensors to marine pollution studies. Satellite sensors are used to observe and characterize ocean pollutants such as industrial wastes and oil. in addition, satellite observations provide information useful in illuminating processes such as eutrophi-cation or air-sea exchange of CO2, that are important in determining the distribution and fate of pollutants.

Satellite technology is an important tool in monitoring and studying ocean pollution. Visible sensors have been used to observe and characterize sewage sludge and industrial wastes dumped at sea. Oil slicks have been observed with Landsat, AVHRR and SAR imagery. Besides directly detecting pollutants, satellite sensors are useful for analyzing ocean processes that are influential in the fate of pollutants. These processes include eutrophication of coastal waters and the distribution of suspended matter. the fate of excess CO2 can be addressed using scatterometer-derived estimates of wind speeds to determine the CO2 exchange coefficient at the sea surface on a global scale.  相似文献   

11.
Management of the land–sea interface is essential for global conservation and sustainability objectives because coastal regions maintain natural processes that support biodiversity and the livelihood of billions of people. However, assessments of coastal regions have focused strictly on either the terrestrial or marine realm. Consequently, understanding of the overall state of Earth's coastal regions is poor. We integrated the terrestrial human footprint and marine cumulative human impact maps in a global assessment of the anthropogenic pressures affecting coastal regions. Of coastal regions globally, 15.5% had low anthropogenic pressure, mostly in Canada, Russia, and Greenland. Conversely, 47.9% of coastal regions were heavily affected by humanity, and in most countries (84.1%) >50% of their coastal regions were degraded. Nearly half (43.3%) of protected areas across coastal regions were exposed to high human pressures. To meet global sustainability objectives, all nations must undertake greater actions to preserve and restore the coastal regions within their borders.  相似文献   

12.
Variation in the timing and abundance of marine food resources is known to affect the breeding behaviour of many seabirds, constraining our understanding of the extent to which these behaviours vary in different parts of a species’ range. We studied incubation shifts of northern fulmars (Fulmarus glacialis) breeding at two colonies in Arctic Canada (High Arctic oceanographic zone) and one colony in the UK (Boreal oceanographic zone) between 2001 and 2005. Fulmars in Arctic Canada had longer incubation shifts than previously reported at more southern colonies, presumably because marine productivity is lower early in the breeding season in the Arctic. Shift durations were particularly long at one colony in years with abnormally late, extensive sea-ice cover, although at the other Arctic colony, where sea-ice cover is predictably late every year, the duration of shifts was shorter than expected. At the Boreal colony, incubation shifts were much longer than expected, similar to Arctic colonies, and likely attributable to poor marine food supplies in the North Sea in recent years. Collectively, our data suggest that fulmars can adjust their incubation rhythm to compensate for poor marine feeding conditions, although this may incur a cost to body condition or reproductive success.  相似文献   

13.
由于大量人类活动的影响,大气CO_2浓度持续增加,其中约1/3被海洋吸收,导致表层海水pH值降低和碳酸盐平衡体系波动,即"海洋酸化"现象。污染物的海洋环境效应一直是全球环境科学领域研究的热点。在实际环境中,海洋酸化往往与污染物共同存在并作用于海洋生态系统,且海洋酸化极有可能改变污染物的海洋环境行为从而影响其毒性效应。但现有研究大多针对海洋酸化或者污染物单独作用下的毒性效应展开,对海洋酸化与污染物的联合毒性效应的研究不足、亟待加强。为此,综述了近年来海洋酸化与典型污染物(重金属、有机污染物)及新型污染物(人工纳米颗粒)的相关文献,重点阐述了海洋酸化对污染物环境行为的影响和海洋酸化与污染物对海洋生物的联合毒性效应,指出当前的研究不足,并对未来的研究方向进行了展望。  相似文献   

14.
Glyphosate has become the most commonly used herbicide worldwide and is reputedly environmentally benign, nontoxic, and safe for use near wildlife and humans. However, studies indicate its toxicity is underestimated and its persistence in the environment is greater than once thought. Its actions as a neurotoxin and endocrine disruptor indicate its potential to act in similar ways to persistent organic pollutants such as the organochlorines dichlorodiphenyltrichloroethane (DDT) and dioxin. Exposure to glyphosate and glyphosate‐based herbicides for both wildlife and people is likely to be chronic and at sublethal levels, with multiple and ongoing exposure events occurring in urban and agricultural landscapes. Despite this, there has been little research on the impact of glyphosate on wildlife populations, and existing studies appear in the agricultural, toxicology, and water‐chemistry literature that may have limited visibility among wildlife biologists. These studies clearly demonstrate a link between chronic exposure and neurotoxicity, endocrine disruption, cell damage, and immune suppression. There is a strong case for the recognition of glyphosate as an emerging organic contaminant and substantial potential exists for collaborative research among ecologists, toxicologists, and chemists to quantify the impact of glyphosate on wildlife and to evaluate the role of biosentinel species in a preemptive move to mitigate downstream impacts on people. There is scope to develop a decision framework to aid the choice of species to biomonitor and analysis methods based on the target contaminant, spatial and temporal extent of contamination, and perceived risk. Birds in particular offer considerable potential in this role because they span agricultural and urban environments, coastal, inland, and wetland ecosystems where glyphosate residues are known to be present.  相似文献   

15.
Two key players in the Arctic and subarctic marine ecosystem are the calanoid copepods, Calanus finmarchicus and C. glacialis. Although morphologically very similar, these sibling species have different life cycles and roles in the Arctic pelagic marine ecosystem. Considering that the distribution of C. glacialis corresponds to Arctic water masses and C. finmarchicus to Atlantic water masses, the species are frequently used as climate indicators. Consequently, correct identification of the two species is essential if we want to understand climate-impacted changes on Calanus-dominated marine ecosystems such as the Arctic. Here, we present a novel morphological character (redness) to distinguish live females of C. glacialis and C. finmarchicus and compare it to morphological (prosome length) and genetic identification. The characters are tested on 300 live females of C. glacialis and C. finmarchicus from Disko Bay, western Greenland. Our analysis confirms that length cannot be used as a stand-alone criterion for separation. The results based on the new morphological character were verified genetically using a single mitochondrial marker (16S) and nuclear loci (six microsatellites and 12 InDels). The pigmentation criterion was also used on individuals (n = 89) from Young Sound fjord, northeast Greenland to determine whether the technique was viable in different geographical locations. Genetic markers based on mitochondrial and nuclear loci were corroborative in their identification of individuals and revealed no hybrids. Molecular identification confirmed that live females of the two species from Greenlandic waters, both East and West, can easily be separated by the red pigmentation of the antenna and somites of C. glacialis in contrast to the pale opaque antenna and somites of C. finmarchicus, confirming that the pigmentation criterion is valid for separation of the two species.  相似文献   

16.
17.
大气是全球持久性有机污染物(persistent organic polutants,POPs)监测的重要环境介质,大气中POPs的采样技术是准确表征大气中POPs赋存水平的关键所在。近年来大气中POPs的采样技术发展很快。本文介绍了大气中POPs的两类采样方法:主动采样法(active air sampling,AAS)和被动采样法(passive air sampling,PAS),总结了新型吸附材料和新型采样器研发的成果,讨论了不同类型的采样方法的特点,对比分析了不同采样方法获得的POPs监测数据,并提出今后应用不同POPs大气采样技术在监测数据可对比性研究方面值得关注的问题。  相似文献   

18.
Several major breeding areas have been defined for the South American sea lion (Otaria flavescens) along the Atlantic Ocean including the Uruguayan and Patagonian coasts. Together with a documented and severe reduction in population sizes caused by commercial hunting in the last century, these areas show opposite population trends. While Patagonian populations are recovering since hunting ceased, Uruguayan populations are declining. In this context, population genetic structure and genetic diversity were studied for the first time with both nuclear (microsatellites) and mitochondrial (control region) markers together. Alternative scenarios were found for both markers. While mitochondrial marker showed geographically structured populations, the nuclear loci showed a lack of geographical structure. These opposite patterns in genetic structure could be explained by female phylopatry and high male dispersion. The reduction in population size caused by commercial hunting did not leave a detectable footprint of bottleneck at the genetic level.  相似文献   

19.
镉在土壤-植物系统中的迁移转化及其影响因素   总被引:61,自引:15,他引:61  
重金属镉(Cd)被列为环境污染物中最危险的五种物质之一。因其极易通过食物链在人体内积累并危害人体健康的特性,环境Cd污染尤其是土壤系统的Cd污染已成为国内外环境污染研究的热点,Cd在土壤一植物系统中迁移转化规律备受关注。本文概述了国内外土壤Cd污染研究现状;在已有研究的基础上,总结并阐述了影响Cd在土壤一植物系统中迁移转化的几个重要因素:土壤基本理化性质(pH值、有机质等)、Zn元素、P元素、陪伴阴离子Cl^-和SO4^2-,其中包括尚未被普遍认识的P元素和陪伴阴离子Cl^-和SO4^2-;并详细论述了各因子对Cd在土壤一植物系统中迁移转化的影响及其可能机理。  相似文献   

20.
R. Gradinger 《Marine Biology》1999,133(4):745-754
The biomass and composition of algal communities in sea ice were studied during two summer expeditions to the central Arctic Ocean and the Greenland Sea. Based on algal pigment determination and cell counts, high biomass accumulations were found at the surface, in the interior and in the bottom layer of the ice floes. Pennate diatoms dominated in the bottom layer, while phototrophic flagellates and cysts of unknown origin were the most abundant taxa in the upper parts. The lowermost 20 to 40 cm contained between 4 and 62% of the entire algal biomass. Consequently, ice biological studies, which deal only with the bottom few centimetres of the ice floes, will underestimate algal biomass and production by factors of up to 25. Differences between the results of this study and published data from coastal locations point towards different biological regimes in Arctic sea ice. The algal biomass in coastal ice is about two orders of magnitude higher and composed mainly of diatoms, probably supported by nutrient influx from the water column. In the pack ice of the central Arctic, nutrient supply is probably reduced, and flagellates contribute substantially to total algal biomass. However, methodological problems might partially be responsible for the observed differences. Received: 12 June 1998 / Accepted: 11 December 1998  相似文献   

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