南极阿德雷岛湖泊沉积210Pb、137Cs定年及其环境意义

摘要

测试了南极阿德雷岛两个湖泊(Y2和G)沉积物的210Pb和137Cs比度。根据210Pb和137Cs比度垂向变化特征。采用CRS模式对G湖进行了定年，年龄跨度大约为134 ± 43年，并据此计算了G湖的沉积速率。近大约100年来G湖呈增长变化的沉积速率以及沉积物210Pb，137Cs蓄积量和沉降通量远大于大气直接沉降，可能是温度升高引起该地区大量冰雪(盖)融水携带补充的结果%The activity of 210Pb and 137Cs of lake sediments, namely Y2 and G, respectively from Ardley Island,Antarctica have been measured. According to the profiles of 210Pb and 137Cs activity, we used CRS model to date the G lake, which spans about 134 ± 43 years. Base on the dating, we estimate the velocity of deposition. The increased sedimentation rates and the inventories of 210Pb and 137Cs as well as their flux being higher than the atmospheric deposition could be reasonably attributed to the supply of a great amount of ice-melt water.