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1.
Surveys of breeding birds on small islands in Penny Strait and Queens Channel, Nunavut Territory, Canada, were conducted in July 2002 and 2003. Approximately 3600 marine birds were observed, with the most common species being Arctic terns ( Sterna paradisaea , N=2400) and common eiders ( Somateria mollissima borealis , N=620). We observed no Ross's gulls ( Rhodostethia rosed ) in either year, and we found ivory gulls ( Pagophila eburned ) only in 2003, even though these species commonly bred here in the 1970s. This previously unsurveyed region supports numerous breeding marine birds, but reproductive success on these small islands may be dependent on annual ice conditions and consequent movements of Arctic foxes ( Alopex lagopus ). 相似文献
2.
Jörg Haarpaintner 《Polar research》1999,18(2):175-182
Persistent polynyas have been observed over several winters in Storfjorden, situated between Spitsbergen and Barentsøya/Edgeøya in the south of the Svalbard archipelago. Polynyas are in general active regions with respect to ocean-atmosphere heat exchange, presenting strong convection phenomena and as such being involved in important water mass formation and having an impact on the marine ecosystem. Hydrographic observations have revealed very dense (cold and saline) brine-enriched bottom waters leaving the continental shelf as gravity driven plumes into the deep sea west of Spitsbergen. Satellite observations, using ERS-2 SAR imagery, reveal the evolution of the Storfjorden polynya during winter 1997/98. After forming a complete ice cover until mid-January, Storfjorden responds dynamically to northerly winds by opening a large latent heat polynya. It occupies at its largest extent a region of up to 6000 km2 of open water, thin ice and brash ice. Comparable in size to other large Arctic polynyas, the Storfjorden polynya might have the same or even greater importance in the thermohaline circulation and bottom water mass formation. Ice production is estimated at 30 km3 in Storfjorden, rejecting around 700 Mt (Megatons) of salt that can raise the salinity in Storfjorden by 0.9-1.0 PSU. First studies and the winter 1997/98 evolution of this polynya are presented in this paper. 相似文献
3.
The hunting of the Greenland right whale in Svalbard, its interaction with climate and its impact on the marine ecosystem 总被引：1，自引：0，他引：1
Louwrens Hacquebord 《Polar research》1999,18(2):375-382
During the 17th and 18th centuries, tens of thousands of Greenland right whales were killed as a result of extensive European whaling in the coastal waters of the Svalbard archipelago. The author reconstructed these whaling activities, examined how the changing climate affected whaling productivity, and considered the consequences of climate and whaling on the species and on the North Atlantic ecosystem. Annual catch records made it possible to calculate the original size of the whale population; its natural migration pattern in the Greenland Sea could be reconstructed using shipping logs and itineraries. Other written sources revealed that besides human hunting activities, climate change played an important role in the elimination of the Greenland right whale from the Arctic marine ecosystem. This elimination made millions of plankton available for other marine mammals, polar cod and planktonfeeding birds. This has caused a major shift in the food web. changing the marine ecosystem in Svalbard. 相似文献
4.
Mark L. Mallory Kerry Woo Anthony J. Gaston W. Eric Davies Pierre Mineau 《Polar research》2004,23(1):111-114
Although the diet of walrus ( Odobenus rosmarus ) is considered varied, records of walrus consuming marine birds are rare in the published literature. In 2001 and 2002 we observed walrus foraging on adult thick-billed murres ( Uria lomvia ) at Coats Island in Nunavut, Canada. Approximately 46% of the attacks on murres were successful, and as many as 67 murres may have been killed in one day in August 2002. All soft parts of the murres were sucked out, with carcasses of only bones, feathers and skin left floating on the water. The extent to which predation on seabirds by walrus occurs across the eastern Arctic is unknown, but it could represent an important source of mortality for murres at some breeding colonies. 相似文献
5.
The marine ecosystem of Kongsfjorden, Svalbard 总被引：16，自引：1，他引：16
《Polar research》2002,21(1):167-208
Kongsfjorden is a glacial fjord in the Arctic (Svalbard) that is influenced by both Atlantic and Arctic water masses and harbours a mixture of boreal and Arctic flora and fauna. Inputs from large tidal glaciers create steep environmental gradients in sedimentation and salinity along the length of this fjord. The glacial inputs cause reduced biomass and diversity in the benthic community in the inner fjord. Zooplankton suffers direct mortality from the glacial outflow and primary production is reduced because of limited light levels in the turbid, mixed inner waters. The magnitude of the glacial effects diminishes towards the outer fjord. Kongsfjorden is an important feeding ground for marine mammals and seabirds. Even though the fjord contains some boreal fauna, the prey consumed by upper trophic levels is mainly Arctic organisms. Marine mammals constitute the largest top-predator biomass, but seabirds have the largest energy intake and also export nutrients and energy out of the marine environment. Kongsfjorden has received a lot of research attention in the recent past. The current interest in the fjord is primarily based on the fact that Kongsfjorden is particularly suitable as a site for exploring the impacts of possible climate changes, with Atlantic water influx and melting of tidal glaciers both being linked to climate variability. The pelagic ecosystem is likely to be most sensitive to the Atlantic versus Arctic influence, whereas the benthic ecosystem is more affected by long-term changes in hydrography as well as changes in glacial runoff and sedimentation. Kongsfjorden will be an important Arctic monitoring site over the coming decades and a review of the current knowledge, and a gap analysis, are therefore warranted. Important knowledge gaps include a lack of quantitative data on production, abundance of key prey species, and the role of advection on the biological communities in the fjord. 相似文献
6.
以夏季北极海域的优势微藻-微单胞藻(Micromonas sp.,CMPP2099)及其关联菌群为切入点,对这两个重要生态学角色之间的相互关系进行了探索研究。实验选择两种不同生长状态的微单胞藻(指数生长期和稳定生长期);并针对微单胞藻的这两种生长状态,添加外源细菌(单一外源细菌和自然外源细菌)作为实验组。研究发现,无论添加细菌与否,都不会对微单胞藻的生长产生影响,微单胞藻均保持着正常稳定的生长状态,且微单胞藻能够促进细菌的增长。稳定生长期实验组的细菌数量明显高于指数生长期的细菌数量。微单胞藻由于其不具胶体形成的细胞特性,在藻菌共生中并没有发现透明胞外聚合颗粒物(transparent exopolymer particles,TEP)大量存在。添加外源细菌对培养液中的微单胞藻生长、细菌的数量、溶解有机碳(dissolved organic carbon,DOC)、透明胞外聚合颗粒物(TEP)和溶解游离氨基酸(dissovled free amino acid,DFAA)的浓度并无影响,而仅仅由于其所在状态不同存在着差异。该研究初次开展的北极中心海域优势藻种及关联菌群之间关系研究,对极地海洋生态系统中的微食物环有着重要的意义,并为在极地海域中的微食物环-优势浮游植物-微生物种群之间的生态协作提供了实验和理论依据。 相似文献
7.
2007-2009年期间的2个越冬期,对鄱阳湖国家级自然保护区白鹤Grus leucogeranus、东方白鹳Ciconia boyciana和小天鹅Cygnus columbianus种群数量和分布进行了监测与研究,结果表明这3个物种的数量一般都在12月达到最高,而10月由于候鸟刚刚迁来以及翌年3月已有部分候鸟迁离,故这2个月份鸟类数量相对较少。保护区的9个湖泊中,沙湖是白鹤、东方白鹳和小天鹅极重要的栖息地,而大湖池是东方白鹳和小天鹅极重要的栖息地。监测发现蚌湖已成为白鹤和东方白鹳重要的栖息地,建议将该湖划为保护区的核心区以加强白鹤等濒危物种的保护。 相似文献
8.
头足类种类众多,分布范围广,是世界上最具开发潜力的海洋生物类群之一,近年来,北极海域渔业资源开发得到了世界各国的重视。据统计,头足类在北极海域共14科26属约43种,分别隶属于乌贼目、八腕目和枪形目,主要种类为僧头乌贼(Rossia palpebrosa)、莫氏僧头乌贼(Rossia moelleri)、深海多足蛸(Bathypolypus arcticus)、深海蛸(Benthoctopus piscatorum)、西伯利亚深海蛸(Benthoctopus sibiricus)、须蛸(Cirroteuthis muelleri)和黵乌贼(Gonatus fabricii),北极大部分头足类都是通过探捕、兼捕或者从其他动物胃含物中获得,大部分分布在格陵兰海、挪威海和巴伦支海等海域。黵乌贼资源丰度为最高,但目前均没有商业性开发。本综述系统收集了分布在北极的头足类种类及其有关资料,为北极头足类资源合理开发及研究北极海域生态系统提供了基础资料。 相似文献
9.
Eva Falck 《Polar research》2001,20(2):193-200
Measurements of nitrate and phosphate taken in the Northeast Water Polynya (NEWP) during the summer of 1993 have been used to identify the contribution of waters of Atlantic and Pacific origin in the polynya. Since waters from the northern Pacific exhibit a deficit in nitrate relative to phosphate due to denitrification in low oxygen waters, the relationship between nitrate and phosphate can be used to distinguish between oceanic waters of Pacific and Atlantic origin. The Pacific Water enters the Arctic Ocean through Bering Strait and flows along the northern coasts of Alaska and Canada. Some of this water exits through Fram Strait and may therefore enter the polynya which is situated above the continental shelf off the north-eastern coast of Greenland. Compared to data from the Greenland Sea, which only show a N–P relationship of typical Atlantic Water, the data from the Northeast Water Polynya show that the upper waters of the polynya bear a clear signal of waters of Pacific origin. In the surface mixed layer an average of about 90% is found to have Pacific N–P characteristics. Below the surface mixed layer the amount of Pacific derived water decreases through the halocline and from about 150 m to the bottom only typical Atlantic Water is found. 相似文献
10.
采用PCR-DGGE方法,对2011年夏季北极王湾表层海水及沉积物细菌的群落分析结果表明,沉积物中的细菌多样性指数高于海水。深水站位(S1和S3)的沉积物细菌群落不但与浮游细菌群落存在差异,并且与浅水站位(S5)也存在差异。位于湾口、湾内的浮游细菌群落组成也存在一定差异。测序结果显示,王湾海洋细菌的多样性组成包括α-变形细菌、γ-变形细菌、δ-变形细菌、放线菌、拟杆菌及厚壁菌等类群。基于定量PCR方法的检测结果表明,位于湾口、湾内的浮游细菌丰度相似,但湾内玫瑰杆菌支系的丰度明显低于湾口。研究结果表明,与湾口相比,王湾湾内的细菌群落受陆源性淡水输入的影响明显,不但表现在细菌群落的多样性组成上,也表现在某些特定细菌类群的数量分布上。 相似文献
11.
Seasonality in an Arctic fjord ecosystem: Hornsund, Spitsbergen 总被引：3，自引：0，他引：3
J. M. WS&#;AWSKI M. ZAJACZKOWSKI S. KWA&#;NIEWSKI J. JEZIERSKI W. MOSKAL 《Polar research》1988,6(2):185-189
Based on two complete years of marine ecological surveys (1981-82 and 1984-85) carried out in the Hornsund fjord on southern Spitsbergen (77N), the seasonal variation of physical and biological processes is presented. Physical parameters reflect the strong seasonality of sun radiation, while water salinity and temperature fluctuate within a narrow range. Concentrations of nutrients and suspended matter depend on meltwater discharge from glaciers and snow cover thickness. The breeding period of most marine invertebrate species is strongly related to the phytoplankton bloom which peaks in May. Ringed seal and polar bear occurrences are directly related to sea ice conditions. Both species are most numerous in Hornsund during March-April. Sea birds which nest in huge colonies along the Hornsund coasts arrive in April-May and leave by August-September except for Fulmars and Brünnich's Guillemots which were observed year-round. 相似文献
12.
黄河三角洲滨海湿地的生物多样性特征及保护对策 总被引：7，自引：0，他引：7
黄河三角洲滨海湿地具有以下生物多样性特点;不同类型的湿地中生物多样性差别显著;生物的态适应类型复杂;生物区系的地理分布成分有一定规律性;资源性动植物物种多;国家重点保护物种和濒危物种多。受自然因素和人为因素的影响,黄河三角洲滨海湿地出现了天然湿地面积减小、土壤盐渍化程度加重、湿地生态服务功能退化、湿地生物多样性水平下降等问题。为了保护黄河三角洲滨海湿地的生物多样性,提出了加强黄河三角洲自然保护区的基础设施建设、实施湿地生态恢复工程、建设黄河三角洲高效生态经济区、加强宣传教育以提高全民生物多样性保护意识、加强黄河三角洲湿地科学研究等对策。 相似文献
13.
In this paper I review recent, small-scale, process-oriented studies of the pelagic distribution of marine birds. I examine the roles played by a variety of hydrographic features, including steep flow gradients (fronts) and water column stratification, in determining the abundance or availability of avian prey. The ice edge/marginal ice zone is a frontal area of particular interest in polar regions. In most oceanic systems we have examples of avian use of a feature, hut only poor information on the importance of the feature for supporting the population as a whole. I review recent studies of the spatial and numerical concordance of marine birds and their prey, and find that these studies have yielded mixed results, with correlations stronger for piscivorous birds, particularly murres foraging on capelin, than for planktivores. Review of investigations of multispecies interactions during foraging shows that flock foraging has both beneficial and negative aspects. Interspecific facilitation of foraging occurs in numerous interactions involving both other species of birds and marine mammals. However, co-occurrence of predators may occur because both seek the same prey, and caution must be used in assessing mutualistic interactions between predatory species. 相似文献
14.
Occurrence of polar seabirds at sea in relation to prey concentrations and oceanographic factors 总被引：2，自引：0，他引：2
The distribution and abundance of breeding and foraging seabirds is usually a reflection of the availability of prey in the marine ecosystems on which the birds depend. At the scale of hundreds of km, differences in marine communities may be reflected in variation in the species composition of resident seabirds. At small scales, environmental features such as fronts or ice can influence where birds will aggregate to forage. Features at which prey become concentrated near the surface are of particular importance to bird species dependent upon small planktonic organisms. Concentrations of foraging seabirds frequently indicate the presence of such features, or of areas of unusually high prey biomass. The absence of birds does not mean that concentrations of potential prey are absent. "Assembly rules," by which one might predict aspects of the marine environment that birds should use in selecting foraging areas are proposed. 相似文献
15.
北极航道按其处于地球上的地理方位可分为东北航道和西北航道,东北航道按航线所处的纬度范围则可分为北极低纬航线(北极近岸航线)、北极中纬航线(作为国际常规航线)、北极高纬航线、挺极航线。"雪龙"号于2012年夏季书写了中国船舶首航东北航道的航海史。"雪龙"号从东北航道的起点白令海峡开始,沿东北航道抵达冰岛,并沿北极高纬航线返回白令海峡,完成往返穿越北冰洋之旅。据此,本文对北极航道的分类提出了一些看法,对东北航道的商业航行情况进行了总结,在此基础上概述了"雪龙"号此次首航东北航道的整个进程和关键问题,同时对中国建立北极航道战略进行了思考并提出了建议。 相似文献
16.
近年来的观测结果显示北极对流层臭氧发生亏损的同时 ,大气中的气态汞浓度也急剧下降。这种现象的发生被认为是大气中活性卤素物种的增多而引起的。活性的卤素物种例如Br/Cl与臭氧作用 ,一方面导致臭氧亏损 ,同时 ,生成BrO/ClO氧化大气中的Hg0 ,使Hg0 转化为活性汞 (RGM)而沉降。北极地区大气中活性卤素物种主要来自海洋大型藻类释放的卤代烃分解和海盐的贡献。在过去的几十年里 ,随气候变暖 ,北极海冰变薄 ,面积减少 ,海洋排放的活性卤素物种浓度增加 ,从而使北极地区大气中的汞沉降通量增加 ,加剧了北极生物圈中的汞污染。由于北极海冰减少变薄趋势还在持续 ,因此 ,北极大气中汞亏损引起的沉降通量增加对生态圈的影响应该引起广泛重视。本文在综述这方面研究的最新进展基础上 ,提出了今后的研究方向。 相似文献
17.
营口市大辽河口湿地是东亚-澳大利西亚迁飞区水鸟的重要栖息地。2019年,采用样线法和定点观察法,对大辽河口湿地水鸟进行监测,运用指数分析方法研究湿地水鸟多样性。结果表明:共记录到湿地水鸟5目10科45种230355只,其中,鸻形目29种,国家Ⅰ级保护动物2种,国家Ⅱ级保护动物5种,IUCN濒危物种2种,易危物种2种,近危物种2种,个体数量超过全球数量1%标准的有13种。从居留型来看,以旅鸟为主,其个体数量占水鸟个体总数的90.06%。大辽河口湿地水鸟多样性季节差异明显,春季的水鸟个体数量最高,8月的水鸟多样性指数最高,3月的水鸟均匀度指数最高。营口大辽河口湿地水鸟多样性高,种群数量大,已达到国际重要湿地的标准,应尽快纳入国家湿地保护体系。 相似文献
18.
2000/2001-2002/2003南极夏季期间,对中国南极长城站所在地乔治王岛菲尔德斯半岛及邻近区海鸟群落组成与种群分布特征进行了观测研究。本文报道了对该地区三次考察期间记录的海鸟共11科25种。其中,有繁殖活动的海鸟12种,优势种有白眉企鹅(Pygoscelispapua)和黄蹼洋海燕(Oceanitesoceanicus),常见种有纹颊企鹅(Pygoscelisantarctica)、巨鹱(Macronectesgiganteus)、花斑鹱(Daptioncapenis)、南极燕鸥(Sternavittata)和灰贼鸥(Catharactaantarctica)等。 相似文献
19.
This paper presents a detailed account of the effect of shipping activity on the increasing trends of air temperatures in the Canadian Arctic region for the period of 1980–2018. Increasing trend of temperature has gained significant attention with respect to shipping activities and sea ice area in the Canadian Arctic. Temperature, sea ice area and shipping traffic datasets were investigated, and simple linear regression analyses were conducted to predict the rate of change(per decade) of the average temperature, considering winter(January) and summer(July) seasons. The results indicate that temperature generally increased over the studied region. Significant warming trend was observed during July, with an increase of up to 1℃, for the Canadian Arctic region. Such increasing trend of temperature was observed during July from the lower to higher latitudes. The increase in temperature during July is speculated to increase the melting of ice. Results also show a decline in sea ice area has a significant positive effect on the shipping traffic, and the numbers of marine vessel continue to increase in the region. The increase in temperature causes the breaking of sea ice due to shipping activities over northern Arctic Canada. 相似文献
20.
为了解广州南沙湿地鸟类迁徙规律,揭示鸟类整体迁徙动态变化,于2014年1月至2018年12月,连续在每月下旬日落前3 h采用样点法和样线法对南沙湿地公园鸟类群落多样性进行调查。结果显示：1) 2014—2018年共记录到鸟类139种,以冬候鸟为主。2）鸟类物种数年际波动较大,丰富度年际变化不明显,即鸟类种类在逐渐增加的同时,个体数量趋于稳定。3）鸟类月度变化呈现明显的候鸟迁徙规律,越冬期急速上升,繁殖期平缓。越冬水鸟迁飞时间有提前的趋势,且在富有食物来源的浅水滩涂地和在无瓣海桑等高大茂盛的红树林群落有更多种类与数量的水鸟分布。最后,建议在注重绿化连续性和整体性的同时,保护和管理鸟类的栖息环境,适当扩大滩涂地面积,增加红树林种植面积以及合理地围垦,科学维持浅水滩涂和红树林种植面积比例,吸引更多越冬候鸟。 相似文献