东南极阿曼达湾湖泊沉积物物源的元素分析

摘要

2008年在东南极阿曼达湾帝企鹅聚集区附近岛屿开展了野外工作,于岛屿湖泊集水区采集到两个短沉积柱样,分别命名为EPI和PI.根据野外实地考察情况和室内分割样品发现EPI柱样主要为泥炭沉积,含有大量水生藻类；PI柱样为黑色泥质沉积,散发出浓烈的粪臭味,沉积物中含有大量的幼年帝企鹅绒毛和少量的残骨.对EPI和PI柱样沉积物、当地风化母岩及水生湖藻进行了部分生源元素和重金属元素浓度分析与对比,结果显示EPI柱样元素含量主要来源于背景母岩和湖藻沉积.PI柱样为帝企鹅粪土沉积序列,沉积物中的TC、TN、TP、Cu、Zn、Hg和Se的含量远远高于风化母岩中的浓度,其主要来源于帝企鹅粪的输入,而Pb元素主要来源于当地风化母岩的贡献.研究显示帝企鹅活动同样可以为南极贫瘠的陆地湖泊系统带来大量的营养物质,但同时也输入了大量的重金属污染元素.%Two short lake sediment cores,EPI and PI,were collected at N Island,Amanda Bay,East Antarctica,during the 2007-2008 seasons.The lithology and sedimentology of the EPI profile indicated a predominance of peat deposit.The PI sediments were composed of black mud,contained many penguin feathers and bones,and had a strong and unpleasant smell of penguin guano.Elemental concentrations in the sediments of the EPI and PI cores,local bedrock,and lake algae,were analyzed.The results indicated that elemental concentrations in the sediments of the EPI core were primarily derived from bedrock and lake algae.The abundance of total carbon (TC) ,total nitrogen (TN) ,total phosphorus (TP) ,Cu,Zn,Hg,and Se in the PI core sediments was much higher than that in local bedrock,suggesting that the sediments were mainly composed of emperor penguin guano,while the element Pb was derived from the geochemical background.This study demonstrates that emperor penguins transport marine-derived nutrients and heavy metal pollutants into lake ecosystems.