红碱淖湖泊沉积记录的近五十年来的环境变化  

Environmental Changes Recorded by Lake Sediments from Hongjiannao Lake during Recent Fifty Years

作　　者：李双[1] 陈硕[1] 张家武[1] 

机构地区：[1]兰州大学西部环境教育部重点实验室,甘肃兰州730000

出　　处：《安徽农业科学》2010年第5期2534-2537,2576,共5页Journal of Anhui Agricultural Sciences

基　　金：国家自然科学基金(40871093)

摘　　要：对红碱淖湖泊短钻岩芯沉积物进行了粒度、碳酸盐以及有机质含量等环境代用指标分析,恢复了红碱淖近五十年以来的环境变化过程。依据红碱淖湖泊沉积记录,可以将红碱淖过去五十年的环境变化大致划分为2大阶段:第一阶段(A阶段,1957～1996年),湖泊环境变化的影响因素以自然因素为主,经历了迅速扩张(1957～1969年)、基本稳定(1969～1990年)和渐趋萎缩(1990～1996年)三个亚阶段;第二阶段(B阶段,1996～2005年),湖泊面积缩小,但指标中碳酸盐含量减少,有机质含量快速增加,指示湖泊沉积环境受人类活动影响强烈,碳酸盐保存条件发生改变,碳酸盐含量在这种情况下已不能指示湖泊环境变化。Particle size,the contents of carbonate and organic matter were analyzed on lake sediments from a short core in Hongjiannao Lake to discuss the environmental changes during the past decades.On the basis of the records,the environmental changes in Hongjiannao Lake was approximately divided into 2 stages.In stage A（1957-1996）,the lake evolution and the environmental change were mainly influenced by natural factors.It contains three sub-stages： A1（1957-1969）,a period of lake expansion,A2（1969-1990）,a stable period with high lake levels,and A3（1990-1996）,a period of gradual extraction of the lake.In stage B（1996-2005）,the lake area still keeps diminishing.During this period,organic matter increased rapidly due to the input of nutrient elements in the catchment.The carbonate content,however,decreased.As the precipitation was decreasing and the temperature was increasing,the decrease of carbonate content could not be explained by either temperature or precipitation change.

关 键 词：红碱淖 粒度 TOC 碳酸盐 环境变化 

分 类 号：X143[环境科学与工程—环境科学]