滇池700年来气候变化与人类活动的湖泊环境响应研究

通过对滇池剖面沉积物质量磁化率、δ18O、δ13C同位素、粒度、矿物成分、CaCO3、有机质、铁、粘土矿物元素的测定,利用210Pb测年,恢复了滇池地区近700年来的气候变化。通过对湖泊沉积记录的分析,发现滇池经历了两个高湖水期和一个低湖水期,具有明显的200年气候周期性;本区气候变化具有冷湿-暖干的气候变化特征。滇池沉积记录包含了人类活动的信息,揭示了人类疏挖海口河,改变了湖泊沉积速率;最近十几年,工农业活动污染物进入湖泊,改变了湖泊的营养度,是滇池迅速富营养化的阶段。

Dianchi Lake Sediment Records of Climate Changes and Humane Activities in the Past 700 Years

Based on 210pb, 14C chronology and the measurements of mass susceptibility, δ13C, δ18O isotope, grain size, mineral component, calcium carbonate, and organic substances, the climate variation during the past 700 years in the area of Dianchi Lake has been established. It has distinct 200 a periodicity with two high and a low water level, Its climate is warm-dry and cold-wet alternated. The study also shows that the sediment has the information of humane activities. The depositional rate was changed by the dredging of Haikou River in Yuan dynasty. In recent decades, the contaminations of agriculture and industry were put into Dianchi Lake and changed the lakes nutrition, eutrophication gets accelerated.