Publications matching your search query
Results 526 to 550 of 968
Zooplankton and benthic invertebrates are important components of polar lakes and often form the highest trophic level in the aquatic food web. Their biodiversity decreases towards high latitudes…
Bacterial community structures in soils collected … from eight sites around Casey Station, Antarctica, were … investigated using denaturing gradient gel electrophoresis … (DGGE) of ampliWed 16S rRNA gene fragments.
Responses by marine top predators to environmental variability … have previously been almost impossible to observe directly. By … using animal-mounted instruments simultaneously recording … movements, diving behavior, and in situ oceanographic properties…
Decadal variations of the quasi-stationary wave amplitude and zonal structure are analyzed using the TOMS data. Seasonal dependence of total ozone content (TOC) is considered.
Anthropogenic CO2 added to the atmosphere during and since the industrial revolution is entering the global ocean. Addition of extra (anthropogenic) CO2 to the ocean changes the carbonate chemistry and the pH of the surface ocean…
Macquarie Island, a small subantarctic island, is home to rockhopper, royal and king penguins, which are often infested with the globally distributed seabird tick, Ixodes uriae. A flavivirus, an orbivirus, a phlebovirus, and a nairovirus were isolated from these ticks and partial sequences obtained.
[1] Using Rayleigh lidar and Mesosphere-Stratosphere- … Troposphere radar at Davis Antarctica (68.6S) during the … 2005–2006 austral summer, we obtained the first Southern … Hemisphere common-volume measurements of Polar … Mesospheric Clouds (PMC) and Polar Mesosphere … Summer Echoes (PMSE).
The Spanish system of longline fishing is used in a range of demersal and semi-pelagic fisheries … throughout the southern hemisphere and has been the source of a large number of seabird fatalities.
Analysis of zonal anomalies in total ozone and thermal tropopause height shows … that ozone depletion during austral spring has a strong influence on the height … and sharpness of the tropopause over West Antarctica. The seasonal change of tropopause … peak height occurs between 9 km…
Interactions between short-beaked common dolphins Delphinus delphis and the … fishing industry of South Australia (SA) have lead to serious concerns over the … long-term viability of the local dolphin population.
Satellite tracking devices were used to examine the at sea movements of southern and … northern giant petrels from Macquarie Island during the Austral summers of 2005–06 … and 2006–07. Time spent at sea for nine northern giant petrels (four breeding adults, five … recently fledged juveniles)…
Past changes in East Antarctic Ice Sheet (EAIS) volume are poorly known and diffi cult to … measure, yet are critical for predicting the response of the ice sheet to modern climate change. In particular, it is important to identify the sources of sea-level rise since the Last Glacial … Maximum (LGM)…
[1] The flow of water beneath the Antarctic Ice Sheet has … recently been shown to involve drainage from and exchange … between subglacial lakes, with flow routing over distances … of >100km. As subglacial water is known to be important to … ice-sheet dynamics…
Sub-Antarctic islands have a diversity of origins in detail but most are volcanic and very young suggesting that they are short-lived and that the distribution would have been very different a few million years ago. They contrast with the common tourist brochure concept of oceanic islands.
We compiled and reviewed 248 cases of reported vessel collisions with small cetaceans worldwide and with large … cetaceans in the Southern Hemisphere. Difficulties were encountered with the comparison of highly variable data in … terms of quality (evidence), sources…
Many parasitic Apicomplexa, such as Plasmodium falciparum, contain an unpigmented chloroplast remnant termed the … apicoplast, which is a target for malaria treatment. However, no close relative of apicomplexans with a functional … photosynthetic plastid has yet been described.
Antarctica is a continent locked in ice, with almost 99.7% of current terrain covered by permanent ice and snow, and clear evidence that, as recently as the Last Glacial Maximum (LGM), ice sheets were both thicker and much … more extensive than they are now.
The sea ice microbial community plays a key role in the productivity of the Southern Ocean. Exopolysaccharide … (EPS) is a major component of the exopolymer secreted by many marine bacteria to enhance survival … and is abundant in sea ice brine channels, but little is known about its function there.
Aims: This study was undertaken to examine and characterize Antarctic marine bacterial isolates and the … exopolysaccharides (EPS) they produce in laboratory culture. Methods and Results:
Exopolysaccharides (EPS) may have an important role in … the Antarctic marine environment, possibly acting as ligands … for trace metal nutrients such as iron or providing … cryoprotection for growth at low temperature and high … salinity. Ten bacterial strains…
Ozone depletion has resulted in large increases in springtime ultraviolet-B radiation (UV) over Antarctic plants since the 1970s. Studies of UV induced DNA damage in three Antarctic moss species have shown Ceratodon purpureus to be the most UV-tolerant…
Summary … • Studies of ultraviolet (UV) light-induced DNA damage in three Antarctic moss … species have shown Ceratodon purpureus to be the most UV tolerant, despite … containing lower concentrations of methanol-soluble UV-screening compounds … than the co-occurring Bryum pseudotriquetrum.
Bacteria play a key role in the world’s oceans, supporting nutrient remineralisation and … mediating carbon transfer. Little is known about annual changes in bacterial concentration, production … and metabolism during the extreme seasonal changes in biological productivity in Antarctic … waters.
Despite being a major pathway for carbon flow in aquatic systems, little is known about … annual changes in microzooplankton grazing in Antarctic waters and its top-down control of phytoplankton.
The effects of ambient solar UV radiation (280 to 400 nm) were determined using 3 natural … marine protist communities incubated in 650 l tanks (minicosms) for 13 to 14 d over the summer … of 2002¨C2003 at Davis Station, Antarctica.