Lipid biomarkers in AD2 penguin droppings-amend soil core from the Ardley Island,Western Antarctic,were dated using 210Pb.Changes in the fatty acid ratios of nC18:2/nC18:0 from the penguin droppings reflect climate ch...Lipid biomarkers in AD2 penguin droppings-amend soil core from the Ardley Island,Western Antarctic,were dated using 210Pb.Changes in the fatty acid ratios of nC18:2/nC18:0 from the penguin droppings reflect climate changes coincident with ENNO events during 1931-2006.The occurrence of the minimum values in the depth of 2-3 and 6-7 cm are consistent with the end of ENSO in 1958 and 1983,respectively,reflecting a lag of the biomarker records in AD2 penguin droppings-amend soil in climatic signatures.This study also reveals that the changes in the relative concentration of n-alkanes nC23,the ratios of nC23/nC17 and nC21 /nC22+,and carbon preferential index(CPI) values collectively indicate the variations of soil microor-ganism and lower plant,which are closely related to climate changes.The ratios of bacterial fatty acids iC15:0/aC15:0 reflect the increasing significance of microorganism activities during the two periods that occurred at the end years of ENSO.Decrease in CPIA value and increase in nC21 /nC22+ indicate that low molecular weight fatty acids are derived from microorganism;and their insignificant correlation with Pr/Ph suggests microorganisms play an important role in the relatively simply ecosystem in the Antarctic and are closely linked to climatic conditions.In addition,the observed penguin community indicates the popula-tion of penguin can largely reflect the impacts of global climate changes on the ecosystem.展开更多
基金supported by National Natural Science Foundation of Chi-na (Grant Nos.40876104 and 41006118)
文摘Lipid biomarkers in AD2 penguin droppings-amend soil core from the Ardley Island,Western Antarctic,were dated using 210Pb.Changes in the fatty acid ratios of nC18:2/nC18:0 from the penguin droppings reflect climate changes coincident with ENNO events during 1931-2006.The occurrence of the minimum values in the depth of 2-3 and 6-7 cm are consistent with the end of ENSO in 1958 and 1983,respectively,reflecting a lag of the biomarker records in AD2 penguin droppings-amend soil in climatic signatures.This study also reveals that the changes in the relative concentration of n-alkanes nC23,the ratios of nC23/nC17 and nC21 /nC22+,and carbon preferential index(CPI) values collectively indicate the variations of soil microor-ganism and lower plant,which are closely related to climate changes.The ratios of bacterial fatty acids iC15:0/aC15:0 reflect the increasing significance of microorganism activities during the two periods that occurred at the end years of ENSO.Decrease in CPIA value and increase in nC21 /nC22+ indicate that low molecular weight fatty acids are derived from microorganism;and their insignificant correlation with Pr/Ph suggests microorganisms play an important role in the relatively simply ecosystem in the Antarctic and are closely linked to climatic conditions.In addition,the observed penguin community indicates the popula-tion of penguin can largely reflect the impacts of global climate changes on the ecosystem.
