云南腾冲青海——酸性湖泊的环境特征

Environmental Characteristics of An Acid Qinghai Lake in Tengchong, Yunnan Province

火山口湖成因和持续酸性地下水补给是腾冲青海呈现酸性湖泊环境的地质基础 .通过对青海环境的实际调查和水、土、生物样品的分析、鉴定 ,结果表明 :湖水具较低pH值、极低的阳离子组成和矿化度 ;沉积物中Ca、Mg、Al、Fe等元素有明显流失 ;湖泊生物种群少且生物量低 ,缺失蓝藻和腹足类、瓣鳃类、甲壳类动物等为其区别于一般中、碱性湖泊最显著的特点 .酸性水介质湖泊系统元素地球化学行为的变化及其对生物的影响———生物贫化和耐酸种扩张 ,既是腾冲青海的基本特点 。

Qinghai Lake is an acid lake and located in Tengchong County, Yunnan province. Qinghai Lake is a crater lake with continuously acid groundwater supply, which is the geological foundation of the acid lake. We analyzed water, soil, sediment and biological samples of Qinghai Lake. As result showing, the water has low pH value, very low cation concentration and mineralization degree, and obviously migration of element Ca, Mg, Al and Fe in sediment. Few species, low biomass and lack of blue green algae, Gastropoda, Lamellibranchia and Crustacea are most notable characteristics distinguished from general neutral and alkaline lakes. Change of element geochemistry behavior of acid aqueous medium in a lake, and its impact on organisms cause the decrease of acid sensitive species and the increase of acid tolerant species, these are the basic characteristics of Qinghai Lake and dynamic mechanism of forming acid lake environment.