Found 14112 items
1 November, 1989 by Roger Worland, William Block
The consumption of fresh plant materials by adults and larvae of Hydromedion sparsutum and Perimylops antarcticus (Col., Perimylopidae) was estimated from the production of faecal pellets and amount of excreted…1 November, 1989 by Roger Worland, William Block
Metabolic rates were studied in adults and larvae of the two phytophagous beetles Hydromedion sparsutum and Perimylops antarcticus (Col., Perimylopidae) indigenous to the Sub-Antarctic island of South Georgia. From the…1 October, 1989
The effects of low temperatures, freezing and desiccation on a cyanobacterium (Phormidium) and an alga (Prasiola) from terrestrial Antarctic habitats were investigated. Net photosynthesis per unit dry weight, measured by…1 October, 1989
Three species of calanoid copepods, Boeckella michaelseni, Parabroteas sarsii and Pseudoboeckella poppei were recorded from 6 freshwater localities in the Husvik area, South Georgia. Of the latter species two distinct…1 October, 1989
The Cretaceous of west James Ross Island, Antarctica represents the proximal fill of a late Mesozoic back‐arc basin that was probably initiated by oblique extension during the early development of…1 October, 1989 by Robert Mulvaney
A 133 m deep Antarctic ice core from Dolleman Island, Antarctic Peninsula, has been profiled by dielectric measurements in the AF‐LF (20 Hz ‐ 100 kHz) frequency range. This has…1 October, 1989
Recent GLORIA and SeaMARC II sidescan sonar surveys have imaged virtually the whole of the Easter microplate, and revealed unprecedented detail and complexity in its tectonic fabric and history. There…Read more on Comprehensive sonar imaging of the Easter microplate
1 September, 1989
The hypothesis that sunlight may induce the enzymes involved in the vitamin D pathway has been tested by comparing the ability to synthesize vitamin D3 and its 25 hydroxy metabolite…Read more on Effect of phototherapy on serum 25-hydroxyvitamin D in the Antarctic
1 September, 1989
An Ekman analysis of the surface drainage winds over a sloping ice surface is reported. Ekman pumping by the boundary layer leads to the formation of an upper tropospheric cyclonic…1 September, 1989
A terrestrial sequence on Livingston Island, South Shetland Islands, known as the Williams Point Beds contains a well-preserved, diverse fossil flora previously assigned a Triassic age. Because of their supposed…1 September, 1989
Upper Jurassic–Lower Cretaceous anoxic mudstones and air-fall ashes of the Nordenskjöld Formation are exposed on the eastern coast of Graham Land. Deformation of the strata has a long history spanning…22 August, 1989 by Michael Pinnock
Study of the near-Earth plasma environment and its interactions with the solar wind has reached a stage where major progress will come only from taking a global view of the…1 August, 1989
The southern elephant seal is among the most sexually dimorphic and polygynous of all mammals: males may be more than 10 times the weight of reproducing females and only the…Read more on Parental investment in southern elephant seals, Mirounga leonina
1 August, 1989 by Jonathan Shanklin
New interferometric observations of the Wolf-Rayet star AS431 using the MERLIN network are presented. These observations had a sensitivity sufficient to map the stellar-thermal continuum radio emission with a beam…Read more on MERLIN observations of the Wolf–Rayet star AS431 (WR147)-a double radio source
1 August, 1989
The development of the thymus was examined in different stages of Harpagifer sp. from Signy Island (South Orkney Islands; 60°43′S, 45°38′W). The thymus was typical, both in position and structural…1 August, 1989
The epiphytic diatoms of filamentous matforming algae in Sombre Lake, Signy Island, South Orkneys, Antarctica were examined in a field study from January to March 1987. Results reveal 1) a…Read more on Depth-related changes in benthic diatom assemblages of a maritime Antarctic lake
1 July, 1989
Schistidium antarctici is the commonest of five bryophytes known in the Windmill Islands area of Wilkes Land, Greater Antarctica. In moist habitats it forms closed carpets, but in dry sites…1 June, 1989
Maternal investment, in terms of pup birth mass, in gestation by Antarctic fur seals (Arctocephalus gazella) was related to the date of birth in two consecutive years. There were significant…Read more on Pre-natal investment in reproduction by female Antarctic fur seals
1 June, 1989
This research examines the energy budget of breeding female Antarctic fur seals, both when food was plentiful and when it is scarce. The energy expenditure and change in body mass…Read more on Foraging energetics of Antartic fur seals in relation to changes in prey availability
1 June, 1989
The structure and function of swimming muscles in Antarctic fish is reviewed, the emphasis being on the highly endemic sub-order Notothenioidei. Adult stages of the vast majority of species swim…Read more on Antarctic fish muscles — structure, function and physiology
1 June, 1989 by John King
Wind and temperature profiles in the lowest 2000 m of the atmosphere at Halley (75°35′S, 26°50′W) have been analysed. Surface winds blow most frequently from the sector 090° ± 45°…Read more on Low-level wind profiles at an Antarctic coastal station
1 June, 1989
The Santa Marta Formation exposed on northern James Ross Island, Antarctica, represents shallow marine shelf sedimentation within an active margin basin. The formation is approximately 1000 m thick, is of…1 June, 1989
The southern polar region offers many significant advantages over its northern counterpart for studies of the interactions of the solar wind, magnetosphere, ionosphere and thermosphere. These mainly arise from the…Read more on Antarctic studies of the coupled ionosphere-magnetosphere system
1 June, 1989 by Eric Wolff, Robert Mulvaney
We have carried out experiments to study the incorporation and movement of HCl within the structure of ice. These involved freezing HCl solutions, and observing them in a scanning electron…1 May, 1989 by William Block
The presence of hemolymph thermal hysteresis antifreeze proteins is described in both the nymphs and adults of the Antarctic oribatid mite, Alaskozetes antarcticus collected from Signy Island in the South…1 May, 1989
Microbial activity in a marine sediment in Factory Cove, Signy Island (60°43′S, 45°38′W), South Orkney Islands in the maritime Antarctic was examined during December 1987 and January 1988. The sediment…1 May, 1989
In crested penguins Eudyptes spp., the first-laid (A) egg is very much smaller than the second (B) egg and, although viable, rarely survives to hatching. I tested the recent hypothesis…1 April, 1989
Maximum net photosynthesis of field‐fresh thalli, illuminated at 200 μmol photons m−2 s−1 (PAR), was attained at 13 °C and 1.10 g g−1 water content. Small but significant rates of…1 April, 1989
A mid-Palaeozoic basement to the Antarctic Peninsula is confirmed by a geochronological study of the gneissose country rock of the Mesozoic magmatic arc of eastern Graham Land. Rb–Sr whole-rock ages…Read more on The significance of mid-Palaeozoic basement in Graham Land, Antarctic Peninsula
1 April, 1989 by Lloyd Peck
V̇o2 was measured for specimens of the Antarctic brachiopod Liothyrella uva and limpet Nacella concinna, using couloximetric techniques. Time-course studies revealed different responses to starvation by each species. N. concinna…Read more on Temperature and basal metabolism in two Antarctic marine herbivores
1 April, 1989
Recruitment of Wandering Albatrosses Diomedea exulans to the breeding population at South Georgia took between 2 and 8 years after they first returned to their natal colony. In successive seasons,…1 April, 1989
By using planetary radio astronomy (PRA), plasma wave system (PWS), and Magnetometer (MAG) data from Voyager 1 and 2 (V1 and V2), essential features of the nightside Jovian plasma sheet…Read more on Jovian plasma sheet density profile from low-frequency radio waves
1 April, 1989
In the interpretation of observed whistlers by curve fitting, systematic travel time residuals appeared which were studied by extensive simulations using ray-tracing, numerical integration and curve fitting. The residuals were…Read more on Error sources and travel time residuals in plasmaspheric whistler interpretation
1 March, 1989
A histochemical study was carried out on muscle fibre types in the myotomes of post-larval and adult stages of seven species of notothenioid fish. There was little interspecific variation in…Read more on Muscle fibre types and metabolism in post-larval and adult stages of notothenioid fish
1 March, 1989
Antarctic research has progressed steadily from the era of reconnaissance studies into a period of problem-oriented scientific investigation. The International Geophysical Year and the intensive work of the 1960s and…1 March, 1989
The design of a computer-controlled climatic simulation cabinet used for mechanical weathering studies on Antarctic rocks is described. It is argued that if the results of simulations are to be…Read more on Antarctic rock weathering simulations: simulator design, application and use
1 March, 1989
Analysis of high-resolution data from slow-ascent radiosondes released at Halley station, Antarctica (75°38′S, 26°40′W), shows that internal gravity wave phenomena are frequently present in the lower troposphere. There is a…1 March, 1989
A new fossil teleost, belonging to the family Aspidorhynchidae Nicholson & Lydekker, Aspidorhynchus antarcticus sp. nov., was obtained from a block of reworked Upper Jurassic tuffaceous mudstone in the lower…Read more on First Aspidorhynchidae (Pisces: Teleostei) from Antarctica
1 March, 1989
Observations of whistler mode signals from the VLF transmitters NAA and NSS in the Northeast U.S.A., made at Faraday, Antarctica (65°S, 64°W), are used to deduce radial plasma drifts and…1 February, 1989
(1) The doubly-labelled water method was used in the first comprehensive study of penguin energetics throughout the reproduction and moult season, comparing gentoo penguins (inshore feeding, sexually monomorphic, share breeding…1 February, 1989
This paper is a review of the literature on turbulent transfer processes over snow and ice surfaces. Current techniques for modelling these transfers for hydrological purposes are discussed.1 January, 1989
An intensive net sampling survey was conducted around the island of South Georgia during November/December 1981. The distribution and copepodite stage structure of the dominant copepods Calanoides acutus, Calanus simillimus,…Read more on Distribution of six major copepod species around South Georgia in early summer
1 January, 1989
A high mortality rate occurs in Antarctic fur seal males on the breeding beaches of Bird Island, South Georgia. The main causes of death were infections of fighting wounds and…1 January, 1989
Environmental impact assessment (EIA) is generally recognized as a useful tool in reducing human impacts on the environment. The Antarctic environment is especially sensitive to harmful perturbation. Regulations introduced under…1 January, 1989 by Eric Wolff
Investigators have used the temporal record of heavy metal and sulphur concentrations in Antarctic snow to assess the extent of global atmospheric pollution in the Southern Hemisphere. These studies would…Read more on Heavy metal and sulphur emissions to the atmosphere from human activities in Antarctica
1 January, 1989
Relationships between size, body condition, age and feeding-attendance patterns during pup rearing of female Antacrtic fur seals Arctocephalus gazella and their effects on the timing of birth and weaning, pup…1 January, 1989 by Andrew Clarke, Alistair Crame
Current knowledge of the break-up of Gondwana during the Tertiary indicates that shallow water marine habitats may have been present continuously, and on occasions were considerably more extensive than at…1 January, 1989 by Alistair Crame
Within the last 25 years there has been a dramatic increase in our knowledge of the fossil record of Antarctica. Improved access to the remotest parts of the continent, the…Read more on Origins and evolution of the Antarctic biota: an introduction
1 January, 1989 by Alistair Crame
In the late Jurassic, the belemnite genera Hibolithes and Belemnopsis were abundant and widespread in Tethys, characterizing a Tethyan Realm that extended south from southern Europe and Asia to Antarctica…Read more on Antarctic belemnite biogeography and the break-up of Gondwana
1 January, 1989 by Andrew Clarke, Paul Rodhouse
Juvenile cuttlefish Sepia offcinalis were hatched and reared in the laboratory at six ration levels and two temperatures. At 12.5 °C there was little growth whereas at 17.5 °C growth…1 January, 1989
In August–September 1987 a group of geophysicists, led by M. Ander of the Los Alamos National Laboratory and M. Zumberge of Scripps Institution of Oceanography, performed a geophysical experiment to…Read more on Investigating variations in the gravitational constant
1 January, 1989 by Lloyd Peck
Ash-free-dry-weight determinations for a representative range of living brachiopod genera have revealed that a consistently high proportion of total organic mass is contained within the shell, partly as the organic…Read more on Physiological constraints on living and fossil brachiopods
1 January, 1989
Glaciological measurements from Austfonna on Nordaustlandet, Svalbard, are needed as a prerequisite to mathematical modelling of ice-mass dynamics. Several upper and lower boundary conditions are set out in detail for…1 January, 1989 by David Vaughan
Results from movement surveys on Rutford Ice Stream are presented with complementary surface-elevation and ice-thickness measurements. Surface velocities of 300 m a−1 occur at least 130 km up-stream of the…Read more on Flow of Rutford Ice Stream and comparison with Carlson Inlet, Antarctica
1 January, 1989 by Richard Horne
It is generally accepted that electrostatic wave energy is the source of terrestrial myriametric radiation (TMR), but there are several theories to suggest how this energy is converted into TMR.…1 January, 1989 by Robert Larter
Multichannel seismic profiles across the Pacific margin of the Antarctic Peninsula show a series of oblique progradational sequences. These sequences exhibit a variety of unusual characteristics that suggest they were…1 January, 1989
Introduced mammals have had a major impact on the biota of islands in the Southern Ocean. Management plans for some islands include control measures for both introduced herbivores and carnivores…Read more on Introduced reindeer on South Georgia—A management dilemma
1 January, 1989
As part of the Winter Weddell Sea Project 1986 (WWSP 86), a buoy, transmitting via TIROS-N satellites to Service Argos, was inserted into an ice floe in the southern Weddell…1 January, 1989
A general method for testing the stability of a stratified, parallel shear flow is presented. The technique allows the routine determination of unstable modes from any high resolution radiosonde data…Read more on A general method for the linear stability analysis of stratified shear flows
1 January, 1989
The structural basement of Alexander Island consists of a wide belt of accretionary complex rocks, the LeMay Group (Bum 1984). This is overlain by ?Cretaceous-Tertiary calcalkalinevolcanic rocks (Bum 1981), and…