The peculiarities of lipids in lacustrine core sediments from Fildes Peninsula, King George Island, Antarctica, are reported. The origin of high-molecular-weight n-alkanes, alkenes,fatty acids, alcohols is supposed to be related to the abundant moss occurring in the sediments.Abundant iso-and anteiso-fatty acids that occur in the sediments indicate a relatively strong bacterial activity in non-ice-cover zone than in other regions in Antarctica. The C18:2 unsaturated fatty acids mainly originate from autochthonous algae in the sediment pool, and the C18:2/C18:0ratios in the profile are controlled more by paleotemperatures than source assemblies. Long-chain alkenones were identified in freshwater lacustrine sediment in Antarctica for the first time, of which Prymnesiophyceae is assumed to be the source organism. High relative abundance of C37:4honologue in long-chain alkenone well correlates to the severely cold climate in Antarctica. 相似文献
Results of grain size analysis and rock magnetic measurements of core NP95-1 from Prydz Bay, Antarctica revealed two series
of ice-rafted detritus layers, which correspond to cold climatic events, Younger Dryas and Heinrich event 1, occurring at
about 11.7-10.3 and 14.3-13.6 kaB.P. respectively. Studies also show that the sequence of paleoclimatic changes in Antarctica
can be correlated with that in other parts of the world, and that the millennia1 climate of the earth could change synchronously
and globally. In addition, magnetic fabric analysis also shows a close relationship between paleoclimatic change and ocean
circulation re-assemblage. 相似文献
The peculiarities of lipids in lacustrine core sediments from Fildes Peninsula, King George Island, Antarctica, are reported. The origin of high-molecular-weight n-alkanes, alkenes, fatty acids, alcohols Is supposed to be related to the abundant moss occurring in the sediments. Abundantiso- andanteiso-fatty acids that occur in the sediments indicate a relatively strong bacterial activity in non-ice-cover zone than in other regions in Antarctica. The C18:2 unsaturated fatty acids mainly originate from autochthonous algae in the sediment pool, and the C18:2C18:0 ratios in the profile are controlled more by paleotemperatures than source assemblies. Long-chain alkenones were identified in freshwater lacustrine sediment in Antarctica for the first time, of whichPrymnesiophyceae is assumed to be the source organism. High relative abundance of C37:4 homologue in long-chain alkenone well correlates to the severely cold climate in Antarctica.
The North China Plain (NCP) is one of the global hotspots of groundwater depletion, groundwater is almost the only source of water for agricultural, industrial and drinking water in this region. After ... 相似文献