Found 14035 items
1 January, 1987 by Andrew Clarke
The zooplankton of the fjords of Svalbard in late summer is dominated by copepodites of Calanus glacialis (JASCHNOV). These are consumed by, among others, the lobate ctenophore Bolinopsis infundibulum (O.F.…Read more on Lipid in an arctic food chain: Calanus, Bolinopsis, Beroe
1 January, 1987
Exploitation of minerals either from continental shelves or land areas free of ice has yet to take place in the Antarctic. The paper considers pressures, commercial, strategic, and possible depletion…1 January, 1987
Travelling ionospheric disturbances with periods in the range 10 < τ < 30 min were observed by an HF Doppier network on the Antarctic Peninsula. A distinction was made between…1 January, 1987
Present threats to Antarctic seabirds and seals when ashore include disturbance and habitat destruction (some directly caused by humans; most through the introduction of rabbits and other grazers; also seal…Read more on The status and conservation of Antarctic seals and seabirds: A review
1 January, 1987
Six island or island groups (Marion and Prince Edwards Islands, Iles Crozet, Iles Kerguelen, Heard and McDonald Islands, Macquarie Island, South Georgia) are considered in this account to belong to…Read more on The biota and conservation status of sub-Antarctic islands
1 January, 1987
The Maritime and Continental Antarctic terrestrial ecosystems are considered in the context of environmental impacts-habitat destruction, alien introductions, and pollution. Their ability to recover from perturbation is discussed in the…1 January, 1987
The 1983–1984 season of the joint British Antarctic Survey‐U.S. Antarctic Research Program geology and geophysics project on the Ellsworth‐Whitmore Mountains crustal block (EWM) has yielded new observations and laboratory data…1 January, 1987
The magmatic arc of the Antarctic Peninsula displays a wide range of features related to extensional tectonics at a convergent margin. Cenozoic extensional features are concentrated in a linear belt…Read more on Extensional tectonics and the fragmentation of Gondwanaland
1 January, 1987
The relationship of West Antarctica to the Precambrian craton of East Antarctica is the longest standing major tectonic problem in Antarctic geology. It has a bearing on Gondwanaland reconstruction but…Read more on Joint U.K.-U.S. West Antarctic Tectonic Project: an introduction
1 January, 1987
The late Paleozoic “basement” rocks that crop out along the Pacific side of the Chonos Archipelago (44°–46°S) can be divided into two north‐south trending belts: (1) an eastern belt formed…1 January, 1987 by Andy Smith, David Vaughan
Rutford Ice Stream drains part of the West Antarctic ice sheet into Ronne Ice Shelf. Much of the drainage basin has a bed well below sea level and is therefore…Read more on Glaciological studies on Rutford Ice Stream, Antarctica
1 January, 1987
Dinoflagellates were identified and counted from preserved vertical net haul samples collected from a station grid centred on South Georgia in austral summer 1981 –1982. All species were scarce in…1 January, 1987
The Dimitobelidae is a Cretaceous belemnite family that was restricted to within the 30° S. palaeolatitude for its Aptian-Maastrichtian range. The family is described in detail from the Antarctic Peninsula…Read more on The Cretaceous Dimitobelidae (Belemnitida) of the Antarctic Peninsula region
1 January, 1987
The deep minimum in total ozone, the ‘ozone hole’, which is now observed each year in early spring in Antarctica, appears to be confined to the cold core of the…Read more on Recent measurements of total ozone at British Antarctic Survey stations
1 January, 1987
The magmatic arc of the Antarctic Peninsula displays a wide range of features related to extensional tectonics at a convergent margin. Cenozoic extensional features are concentrated in a linear belt…Read more on Lithospheric extension on the Antarctic Peninsula during Cenozoic subduction
1 January, 1987
Linear belts 50–100 km in width of long-wavelength positive magnetic anomalies exceeding 500 nT are observed on continental blocks of the Scotia arc. The most developed is the West Coast…Read more on Continental magnetic anomalies and the evolution of the Scotia arc
1 January, 1987
Aspects of the breeding biology of the whitc‐chinned petrel Procellaria aequinoctialis were studied at South Georgia. Laying, hatching and fledging dates, together with egg and adult measurements, rate of weight…1 January, 1987
Antarctic fish of the family Channichthyidae (Icefishes) lack the respiratory pigments haemoglobin and myoglobin. The morphometrics and ultrastructure of the ventricular myocardium of a benthic icefish,Chaenocephalus aceratus has been compared…Read more on Morphometrics and ultrastructure of myocardial tissue in Notothenioid fishes
1 January, 1987 by William Block
Soil biological processes which have been studied in the north are extended and compared with those of the south polar region. Much can be learned from exploiting the biological similarities…Read more on Soil biological processes in the North – and South
1 January, 1987
1. Oxygen consumption, mitochondrial content and enzyme activities were determined in identified muscle fibre types of the ‘haemoglobin-less’ icefish Chaenocephalus aceratus Lonnberg. 2. Small bundles (2–12) of fast and slow…1 January, 1987
Second only to auroral kilometric radiation as the Earth's most prominent radio emission, magnetospheric nonthermal continuum radiation has been the subject of numerous observational and theoretical investigations. It has been…Read more on The magnetopause as a source of nonthermal continuum radiation
1 January, 1987
57 morphological characters were scored on a sample of 46 male and 55 characters on a sample of 40 female Gamasellus racovitzai, which had been collected from 10 localities in…1 January, 1987
(1) The sub-Antarctic island of South Georgia has a species-poor vascular flora that is not adapted to grazing by vertebrates. Consequently, reindeer (Rangifer tarandus L.) introduced to different areas of…1 January, 1987 by William Block
Polyacrylamide gel electrophoresis and subsequent esterase staining provide an alternative to immunological methods for investigating the diet of microarthropods which cannot be observed directly. Attack rates in field populations of…1 January, 1987 by Andrew Clarke, Lloyd Peck
The living terebratulid articulate brachiopod Liothyrella uva (Jackson 1912) was sampled from a shallow water population at Signy Island, South Orkney Islands, Antarctica. Neither shell height nor shell breadth were…1 January, 1987
In northern Palmer Land, Antarctic Peninsula, the magmatic arc has developed by the interaction of compressional and extensional tectonics. Periods of magmatism and arc compression in the Early Jurassic and…Read more on Structural evolution of the magmatic arc in northern Palmer Land, Antarctic Peninsula
1 January, 1987
Seventy‐two new Rb‐Sr whole‐rock analyses are reported for Haag Nunataks, Mount Woollard, the Whitmore Mountains, the Pirrit and Nash hills, and Pagano Nunatak. For Haag Nunataks, three isochrons for gneisses…1 January, 1987
A synthetic aperture radar (SAR) technique has been used to image part of the grounding-line region of Bach Ice Shelf in the Antarctic Peninsula. The radar was sledge-mounted and operated…Read more on Imaging subglacial topography by a synthetic aperture radar technique
1 January, 1987 by Keith Nicholls
A model pulsed wavefield is presented that enables the behaviour of the associated wave dislocations to be computed exactly. It consists of three intersecting beams of plane-wave pulses. Because the…Read more on Three-beam model for studying dislocations in wave pulses
1 January, 1987
We report a distribution—free approach to the detection of density—dependence in the variation of population abundance, measured by a series of annual censuses. The method uses the correlation coefficient between…Read more on The detection of density-dependence from a series of annual censuses
1 January, 1987
This paper discusses the present understanding of ionospheric storms, in particular storm effects in the F-layer and their relationship to changes of thermospheric composition. After summarizing the main effects of…1 January, 1987
Over the past 50 years, ideas relating to the physical features and dynamics of ice sheets have evolved materially, primarily due to modern technological advances in the acquisition of basic…Read more on Fifty years of progress in understanding ice sheets
1 January, 1987
Average north polar currents for the winter season have been derived from geomagnetic hourly means at six levels of geomagnetic activity. The twin-vortex pattern, normally associated with more disturbed conditions,…Read more on The effect of geomagnetic activity on north polar currents in winter
1 January, 1987
The poleward edge of the main ionospheric trough can often be regarded as the ionospheric signature of the equatorward boundary of the plasma sheet. We use Advanced Ionospheric Sounder observations…Read more on Is the poleward edge of the trough a sensitive indicator of geospace interactions?
1 January, 1987 by Paul Rodhouse
Cephalopod beaks from the stomach contents of “wandering albatross” (Diomedea exulans L.) chicks from Bird Island, South Georgia, were sampled between May and September in 1983 and 1984. Lower beaks…Read more on Cephalopod prey of the wandering albatross Diomedea exulans
1 January, 1987
Optical methods of studying the atmosphere are one valuable means of investigating atmospheric behaviour at heights ranging from less than 1 km to several hundred km. Some examples are given…Read more on Antarctica — A unique laboratory for atmospheric studies by optical methods