954 resultados para 57-440
Resumo:
For several years Georgia has been experiencing processes which may be interpreted as symptoms of a deepening, multidimensional social and political crisis. Reforms have lost momentum, stagnation has set in, and in some areas the situation has begun to revert to the pre-revolution status (including rising crime levels). The Georgian political system has found itself in a serious crisis, while society has become increasingly frustrated and apathetic, mainly because people’s standards of living have been stagnating. This political and social malaise has been breeding Euro-scepticism and disenchantment with the West. A country that had been firmly navigating westwards, Georgia has now started drifting and slipping into malaise. This risks reversing what the country has achieved so far in the internal dimension, increasing instability and triggering a crisis in the pro-Western vector of Tbilisi’s foreign policy. While that may not necessarily mean a turn towards Russia, in the present situation it has been easier for Moscow to pursue its own interests in the region. Should Tbilisi’s pro-Western course become reversed or permanently stagnant, that would entail grave consequences for the country itself and beyond. It would be a defeat for the West and would undermine the European aspirations of countries like Ukraine or Moldova.
Resumo:
Marine organic matter (OM) sinks from surface waters to the seafloor via the biological pump. Benthic communities, which use this sedimented OM as energy and carbon source, produce dissolved organic matter (DOM) in the process of remineralization, enriching the sediment porewater with fresh DOM compounds. We hypothesized that in the oligotrophic deep Arctic basin the molecular signal of freshly deposited primary produced OM is restricted to the surface sediment pore waters which should differ from bottom water and deeper sediment pore water in DOM composition. This study focused on: 1) the molecular composition of the DOM in sediment pore waters of the deep Eurasian Arctic basins, 2) whether the signal of marine vs. terrigenous DOM is represented by different compounds preserved in the sediment pore waters and 3) whether there is any relation between Arctic Ocean ice cover and DOM composition. Molecular data, obtained via 15 Tesla Fourier transform ion cyclotron resonance mass spectrometer, were correlated with environmental parameters by partial least square analysis. The fresher marine detrital OM signal from surface waters was limited to pore waters from < 5 cm sediment depth. The productive ice margin stations showed higher abundances of peptides, unsaturated aliphatics and saturated fatty acids formulae, indicative of fresh OM/pigments deposition, compared to northernmost stations which had stronger aromatic signals. This study contributes to the understanding of the coupling between the Arctic Ocean productivity and its depositional regime, and how it will be altered in response to sea ice retreat and increasing river runoff.
Resumo:
Recent observations on postglacial emergence and past glacier extent for one of the least accessible areas in the Arctic, northern Novaya Zemlya are here united. The postglacial marine limit formed 5 to 6 ka is registered on the east and west coasts of the north island at 10 ± 1 and 18 ± 2 m aht, respectively. This modest and late isostatic response along with deglacial ages of >9.2 ka on adjacent marine cores from the northern Barents Sea indicate either early (>13 ka) deglaciation or modest ice sheet loading (<1500 m thick ice sheet) of Novaya Zemlya. Older and higher (up to 50 m aht) raised beaches were identified beneath a discontinuous glacial drift. Shells from the drift and underlying sublittoral sediments yield minimum limiting 14C ages of 26 to 30 ka on an earlier deglacial event(s). The only moraines identified are within 4 km of present glacier margins and reflect at least three neoglacial advances in the past 2.4 ka.