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1.
Jacobsen, N. Kingo, et.al. Report of activities at Tugtuligssuaq, Melville Bugt, 1978–79. Geografisk Tidsskrift 80: 29–44. Copenhagen, June 1980.

A joint cooperative Greenland/Danish expedition to the Melville Bugt area, Tugtuligssuaq/Kap Seddon to throw light on the Eskimos' immigration routes to Greenland seen in relation to climatic fluctuations. Studies of geography, botany, zoology, archaeology, and ethnohistory have been carried out.  相似文献   

2.
Bowhead whales, Balaena mysticetus, belonging to the Davis Strait/Baffin Bay stock, have historically in Baffin Bay and Davis Strait, including waters along the west coast of Greenland in and near the entrance of Disko Bay. Aerial surveys of the Disko Bay region during late winter (1981, 1982, 1990,1991, 1993 and 1994) showed that it was still visited regularly by a few tens of whales. Commercial whaling on bowheads in Baffin Bay and Davis Strait ended in about 1915, but occasional killing continued until as recently as the 1970s. The low numbers of bowheads observed off West Greenland in recent years are consistent with the results of surveys of the summering grounds in the eastern Canadian Arctic, indicating that any recovery has been exceedingly slow. The only conclusion supported by the data is that the current stock size is a small fraction of what it was prior to commercial whaling.  相似文献   

3.
The extent and duration of sea ice in Baffin Bay and Davis Strait has a major impact on the timing and strength of the marine production along West Greenland. The advance and retreat of the sea ice follows a predictable pattern, with maximum extent typically in March. We examine the area of sea ice in March in three overlapping study regions centred on Disko Bay on the west coast of Greenland. Sea ice concentration estimates derived from satellite passive microwave data are available for the years 1979-2001. We extend the record back in time by digitizing ice charts from the Danish Meteorological Institute, 1953-1981. There is reasonable agreement between the chart data and the satellite data during the three years of overlap: 1979-1981. We find a significant increasing trend in sea ice for the 49-year period (1953-2001) for the study regions that extend into Davis Strait and Baffin Bay. The cyclical nature of the wintertime ice area is also evident, with a period of about 8 to 9 years. Correlation of the winter sea ice concentration with the winter North Atlantic Oscillation (NAO) index shows moderately high values in Baffin Bay. The correlation of ice concentration with the previous winter's NAO is high in Davis Strait and suggests that next winter's ice conditions can be predicted to some extent by this winter's NAO index.  相似文献   

4.
Sea-associated birds were recorded during systematic aerial surveys of marine mammals in south-western Greenland, the Davis Strait and southern Baffin Bay in March 1981, 1982, 1991, 1993 and in April 1990. Most surveys included the northern part of the south-west Greenland Open Water Area, which in most years lies between 62° and 67°N. but none of the area south of 63°N was surveyed. The bird data are generally semi-quantitative and provide information on distribution and relative abundance in different areas during different years, under different ice conditions.
In all years, regardless of ice conditons, large concentrations of king eiders Somateria spectabilis were found in water <50m deep on the shallow banks off south-west Greenland, especially on the northern portion of the Store Hellefiskebanke. We estimate that in 1981 and 1982 about 270000 king eiders overwintered on the banks off south-west Greenland.
Compared to king eiders, flocks of common eiders Somateria mollissima were considerably more dispersed. They were found mainly close to shore off south-west Greenland, where they were distributed along rocky coastlines.
A few thousands of large guillemots Uria spp. were recorded in the study area in March 1981, 1982, 1991 and 1993, but large numbers (>65000 birds) were recorded north of the south-west Greenland Open Water Area in April 1990. indicating that northward spring migration was underway at this time.  相似文献   

5.
Fishing Arctic Foxes Alopex lagopus on a rocky island in West Greenland   总被引：1，自引：1，他引：0  
On a small barren island in Disko Bay, West Greenland, 195 hours were spent observing Arctic Foxes at their den and the nearby coast. Their main food was found to be live, caught fish, and the activity of the foxes was correlated with the tidal height. S. M. Nielsen, Arctic Station, University of Copenhagen. DK-3953 Godhavn, Greenland.  相似文献   

6.
Winter seabird distribution and abundance off south-western Greenland, 1999   总被引：3，自引：0，他引：3  
South-western Greenland constitutes an internationally important wintering area for many seabird species. Several species of management concern have a predominantly near-coastal distribution, though available information about seabird numbers is mostly confined to offshore waters. Here we report on extensive aerial surveys conducted in March 1999, covering the coastal waters (up to 15-20 km from the mainland coast) and fjords of south-west Greenland. The most widespread and numerous species were estimated as 463 000 common eiders ( Somateria mollissima ), 153000 king eiders ( S. spectabilis ), 125000 thick-billed murres ( Uria lomvia ), 94 000 long-tailed ducks ( Clangula hyemails ), and 12 000 black guillemots ( Cepphus grylle ). A total of 19 bird species were recorded. The estimates for common eider and long-tailed duck approximately represent the entire winter population in south-western Greenland while estimates for the other species represent only an unknown proportion since their distribution continues further offshore. Waters around Nuuk and within the Julianehåbsbugten (Julianehåb Bay) area were identified as areas of high seabird density. A large proportion of the common eider population was aggregated in the fjord systems (22%), calling attention to the importance of fjords for this species. In contrast, pelagic seabird species appear to be absent from the fjords. The large winter population of common eider reveals the importance of south-western Greenland as a key wintering area for the eastern Canadian breeding population. The western Greenland breeding population is the only other contributor, probably amounting to no more than 15 000 pairs.  相似文献   

7.
Hasholt, Bent: Sediment Transport in a Proglacial Valley, Sermilik, East Greenland, Geografisk Tidsskrift 92:105–110, Copenhagen 1992.

Detailed investigations of sediment transport have been carried out in a proglacial valley at the Mitdluagkat Glacier in East Greenland. The results from 1989, 1990 and 1991 have been compared with earlier measurements of sediment transport. The hydrologie regime will be described and the effect of the development of an icing on the fluvial transport will be discussed.  相似文献   

8.
邓占球 《极地研究》1995,7(3):67-73
本文报道了采自南极乔治王岛东部梅尔维尔半岛的非造礁珊瑚化石：Ｆｌａｂｅｌｕｍ（Ｆｌａｂｅｌ－ｌｕｍ）ｒａｒｉｓｅｎｔａｔｕｍＲｏｎｉｅｗｉｃｚａｎｄＭｏｒｙｃｏｗａ，从其产出的层位表明，在晚第三纪中新世的时期中，在南极洲已有分布  相似文献   

9.
钦州湾不同类型红树林土壤因子调查与分析   总被引：1，自引：0，他引：1  
对钦州湾的红树林资源进行实地踏查后,选取中盐区光滩(CK1)和4个红树林类型、高盐区光滩(CK2)和2个红树林类型的土壤进行调查研究,测定土壤理化性状和养分等10个因子,并计算土壤肥力指数。结果表明:①不同类型的红树林土壤因子不同,只有高盐区3个样地的土壤pH值和容重没有显著差异,其他类型的各指标均存在显著差异;②与光滩相比,红树林能改变其生长的土壤理化性状,加重土壤盐渍化和酸化,有利于重金属的沉积,同时,也增加土壤有机质和养分含量,提高土壤肥力。  相似文献   

10.
After ~ 11,000 years of glacio-isostatically induced forced regression, geomorphological evidence indicates that the coastline of eastern Melville Island, western Canadian Arctic Archipelago, is now being transgressed. Recently developed coastal features associated with this transgression include: drowned gullies and small estuaries, barriers and lagoons, barrier islands, erosional notches, backstepping beaches, and drowned tundra vegetation and vehicle tracks dating from the 1970s. We mainly attribute this relative sea-level rise to the eastward migration of a peripheral crustal forebulge. Furthermore, the reported transgression also includes a component from recent eustatic sea-level rise during the 20th century. Recent earthquakes recorded in the Gustav-Lougheed Arch Seismic Zone located in Byam Martin Channel, 70 km east of Melville Island, suggest that neotectonics could also be involved in local relative sea-level adjustments. Other factors associated with global warming, especially the formation of an earlier shore-ice lead coupled with increased storm activity might also be responsible for some of the coastal changes. Our study indicates that the current zero isobase, separating areas of net transgression from those of net regression, is now located off the east coast of the island. Our field observations support recent glacio-isostatic modelling that shows the island is presently undergoing a transgression.  相似文献   

11.
对东南极普里兹湾海区ＮＰ９３－２柱样的古地磁研究，结果指示出两个地磁场反极性漂移，其中之一位于６０－６７．５ｃｍ，而６７．５－７２．５ｃｍ处经１４Ｃ测年为１０３１５±８００ａＢ．Ｐ．，推算该反极性漂移的年龄为９９８０－８８８０ａＢ．Ｐ．，可能是哥德堡反极性漂移（Ｇｏｔｈｅｎｂｕｒｇ，１２０００ａＢ．Ｐ．前后）在该沉积物中的记录；另一反极性漂移位于２７．５－３２．５ｃｍ处，经１４Ｃ测年为５３９０±６００ａＢ．Ｐ．。国际上所见报导的资料中尚无相应年龄的反极性事件可以与之对比。只有国内一些地区发现的反向极性漂移记录与之接近，但这些反极性漂移是否为同一事件的反映，或该反极性漂移本身是否真实存在，目前还难于论定，有待今后进一步工作加以证实  相似文献   

12.
Earlier work in northeast Greenland has suggested a limited advance of the Greenland Ice Sheet during the Last Glacial Maximum (LGM). However, this concept has recently been challenged by marine geological studies, indicating grounded ice on the continental shelf at this time. New 10Be‐ages from the Store Koldewey island, northeast Greenland, suggest that unscoured mountain plateaus at the outer coast were covered at least partly by cold‐based ice during the LGM. It is, however, still inconclusive whether this ice was dynamically connected to the Greenland Ice Sheet or not. Regardless of the LGM ice sheet extent, the 10Be results from Store Koldewey add to a growing body of evidence suggesting considerable antiquity of crystalline unscoured terrain near present and Pleistocene ice sheet margins.  相似文献   

13.
Concentrations (ppm = ug/g dry weight) of total mercury (Hg) were determined in hair of polar bears ( Ursus maritimus) from northwestern Greenland (N = 22; period of sampling: 1978-1989), eastern Greenland (N = 44: 1984-1989) and Svalbard (N = 31; 1980). For subadults (2-6 years of life), adults (7-10 years). and old bears (>10 years), concentrations of total Hg in hair were not found to be dependent on age or sex. A decreasing trend in Hg concentrations was found from west to east. The mean concentrations of total Hg in hair (cubs of the year and yearlings excluded) were: northwestern Greenland, x = 8.38 ppm (min.-max.: 4.71-14.19 ppm. N = 21); eastern Greenland: x = 4.58 ppm (min.-max.: 2.50-8.83 ppm. N = 41); and Svalbard, x = 1.98 ppm (min.-max.: 1.02-4.55 ppm, N = 29). Concentrations found in northwestern Greenland were similar to those reported by others from the hair of polar bears sampled within management zone F of the eastern Canadian High Arctic. Concentrations of total Hg in polar bear hair from eastern Greenland were similar to concentrations found by others in contemporary (1988) material collected during spring in western Svalbard. However, the mean concentration of total Hg in the 1980 Svalbard material, which was collected during July-September, was significantly lower than concentrations found in samples taken during late winter and spring in eastern Greenland and at Svalbard, respectively. Presumably the relatively low concentrations found in the 1980 Svalbard sample arc attributable to the period of moult and hence a larger proportion of newly grown hair in the individual samples. In a subsample consisting of internal tissues from 19 polar bears from eastern Greenland (1984-1987), concentrations of total Hg in hair correlated positively with concentrations of total Hg (wet weight) in muscle (N = 6), liver (N = 19) and kidney (N = 19) tissue. For liver and kidney tissue these relationships were statistically significant.  相似文献   

14.
A total of 179 redfish (Sebastes spp.), 495 Greenland halibut (Reinhardtius hippoglossoides) and 133 starry ray (Raja radiata) stomachs were collected from the catch in four bottom trawl hauls carried out at 6-hour intervals on a shrimp fishing ground off West Greenland in September 1991. Between 90 and 96% of the total catch in each of the four trawl hauls consisted of northern shrimp (Pandalus borealis) . The fish catches were small and dominated by redfish, Greenland halibut, starry ray and polar cod (Boreogadus saida) . The stomach contents of redfish consisted of crustaceans (mysiids, hyperiids and copepods) followed by cephalopods, northern shrimp and redfish. Fish (mainly redfish), cephalopods and northern shrimp were the most important stomach content of Greenland halibut. The stomach content of starry ray consisted mainly of northern shrimp and redfish. Plots of redfish and shrimp sizes found in the stomachs of Greenland halibut and starry ray versus predator size showed only weak associations indicating that availability overruled the importance of size-dependent prey preference. The present study indicates that redfish, Greenland halibut and starry ray feed throughout the 24-hour cycle with no clear diel feeding rhythms.  相似文献   

15.
In october 1990 an automatic weather station was established at the Arctic Station (65° 15', 53°31'W), Qeqertarsuaq (Godhavn), Central West Greenland. The Station register parameters each 20 minutes, and the paramters have been described in an earlier paper in this journal by Nielsen et al.(1995). The present paper summarizes meteorological parameters during 1999.

During a field campaign in 1999, woody remains from Salix glauca were found on a nunatak, 515 m. a.s.l. on the Mittivakkat Glacier, South East Greenland. Radio carbon dating determined the age of a wood sample to AD 640. Together with analyses of macroscopic botanical remains and insect rests in peaty material found nearby, these results indicate, that a warmer climate prevailed near the glacier around AD 600. These findings are in accordance with temperature records based on studies of ice cores from the Greenland Ice sheet.  相似文献   

16.
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   

17.
Jakobsen, Bjarne Holm: Preliminary Studies of Soils in North- East Greenland between 74° and 75° Northern Latitude. Geografisk Tidsskrift 92:111–115. Copenhagen 1992.

The geography of soils has been studied in north-east Greenland between latitudes 74° and 75° N. The study ranges from the outer coast to the interior of the ice-free land area. Well-drained soils show a characteristic sequence determined by the east-west climatic gradient. Fossil soil characteristics and secondary formed features supply information on the palaeoclimate.  相似文献   

18.
Summary. Palaeomagnetic investigations are reported from 24 sites in the Proterozoic Zig-Zag Dal Basalt Formation and 12 sites in the Midsominersø Dolerites of eastern North Greenland. The Zig-Zag Dal Basalt is a typical tholeiitic flood basalt sequence, and dolerite intrusions in the underlying sandstones are thought to be genetically related to the basalts.
After a detailed AF demagnetization programme 19 sites in the basalts and 10 sites in the dolerites reveal one stable component of magnetization, probably of TRM and/or CRM origin residing in small single domain titano-magnetite grains. The degree of anisotropy has not affected the direction of the remanent magnetization. The maximum axis of the anisotropy ellipsoid is parallel to the flow direction of the magma, whereas the minimum axis is perpendicular to the flow plane.
Only one polarity of the geomagnetic field was found. The mean palaeomagnetic pole positions for the two rock types are not significantly different (basalt: 12.2°S, 62.8°E with A 95= 3.8°; dolerites: 6.9°S, 62.0°E with A 95 = 5.1°). After correction for Phanerozoic drift of Greenland the two mean poles compare closely to a relevant North American APW-curve for 1250–1350 Ma, in good agreement with Rb-Sr isochron ages of 1250 Ma obtained for the intrusives. The palaeogeographical position of Greenland was near equator with the major geographical axis orientated E-W.  相似文献   

19.
We present glacial geologic and chronologic data concerning the Holocene ice extent in the Stauning Alper of East Greenland. The retreat of ice from the late-glacial position back into the mountains was accomplished by at least 11 000 cal years B.P. The only recorded advance after this time occurred during the past few centuries (the Little Ice Age). Therefore, we postulate that the Little Ice Age event represents the maximum Holocene ice extent in this part of East Greenland.  相似文献   

20.
《Basin Research》2018,30(3):373-394
Continental breakup between Greenland and North America produced the small oceanic basins of the Labrador Sea and Baffin Bay, which are connected via the Davis Strait, a region mostly comprised of continental crust. This study contributes to the debate regarding the role of pre‐existing structures on rift development in this region using seismic reflection data from the Davis Strait data to produce a series of seismic surfaces, isochrons and a new offshore fault map from which three normal fault sets were identified as (i) NE‐SW, (ii) NNW‐SSE and (iii) NW‐SE. These results were then integrated with plate reconstructions and onshore structural data allowing us to build a two‐stage conceptual model for the offshore fault evolution in which basin formation was primarily controlled by rejuvenation of various types of pre‐existing structures. During the first phase of rifting between at least Chron 27 (ca. 62 Ma; Palaeocene), but potentially earlier, and Chron 24 (ca. 54 Ma; Eocene) faulting was primarily controlled by pre‐existing structures with oblique normal reactivation of both the NE‐SW and NW‐SE structural sets in addition to possible normal reactivation of the NNW‐SSE structural set. In the second rifting stage between Chron 24 (ca. 54 Ma; Eocene) and Chron 13 (ca. 35 Ma; Oligocene), the sinistral Ungava transform fault system developed due to the lateral offset between the Labrador Sea and Baffin Bay. This lateral offset was established in the first rift stage possibly due to the presence of the Nagssugtoqidian and Torngat terranes being less susceptible to rift propagation. Without the influence of pre‐existing structures the manifestation of deformation cannot be easily explained during either of the rifting phases. Although basement control diminished into the post‐rift, the syn‐rift basins from both rift stages continued to influence the location of sedimentation possibly due to differential compaction effects. Variable lithospheric strength through the rifting cycle may provide an explanation for the observed diminishing role of basement structures through time.  相似文献   

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