滇东南峰林湖盆区表层岩溶泉水化学动态变化分析

为探究不同表层岩溶带岩溶水系统和人类干扰方式下滇东南峰林湖盆区表层岩溶泉地球化学变化特征及其影响因素,利用CTDP300水质检测仪,对不同地质背景下的两泉域的水化学性质从月动态和降雨动态两个尺度进行了一个水文年的观测。结果表明:(1)菜花箐泉理化指标季节动态变幅较大:水温为4.6℃,电导率为302μs/cm,pH为0.66,水浊度为255.1;火把洞泉变幅相对较小:水温为3.3℃,电导率为225μs/cm,pH为0.5,水浊度9.8。(2)无雨时:菜花箐泉气温与水温、电导率、pH呈正相关关系;火把洞气温与水温呈现正相关关系,水温与电导率、pH呈现负相关关系。(3)强降雨时:菜花箐泉在降雨初期水温、电导率、水浊度均出现峰值,pH呈现低值。在降雨中后期,电导率大幅度上升,在6 h内从189μs/cm上升到405μs/cm,pH出现峰值后呈波动下降趋势。火把洞泉在降雨初期水温与电导率、pH呈正相关关系,各自呈现本期间峰值。在降雨持续10 h后,pH、电导率均呈现下降趋势。(4)弱降雨气候条件下:菜花箐和火把洞泉的理化指标变幅都较小,在降雨初期、中期和后期两泉域pH、电导率都出现稀释效应曲线。

ANALYSIS ON HYDROCHEMICAL VARIATIONS OF EPIKARST SPRING IN SOUTHEAST YUNNAN PEAK FOREST-LAKE BASIN

In order to explore the hydrochemical change and its influencing factors of epikarst zone under human disturbances in the Southeast Yunnan peak forest-lake basin,we investigated physical and chemical properties of the two spring area in a hydrological year.Results showed that for the Caihuaqing spring,seasonal dynamics ofphysicochemical indicators had a large amplitude.The water temperature was 4.6 degrees Celsius,the conductivity was 302 μts/cm,pH was 0.66,water turbidity was 255.1.For the Huobadong spring,the seasonal dynamics of the physical and chemical indicators had relatively small variations.The water temperature was 3.3 degrees Celsius,the conductivity was 225μs/cm,pH was 0.5,water turbidity was 9.8.Under normal weather conditions,air temperature and water temperature,conductivity and pH were positively correlated for the Caihuaqing spring.While for the Huobadong spring,air temperature and water temperature were positively correlated,but water temperature was negatively correlated with conductivity and pH.Under the condition of heavy rainfall,the Caihuaqing spring presented peaks of water temperature,conductivity and turbidity while low pH value at the early stage of rainfall.At the late stage of rainfall,the conductivity increased significantly in 6 hours from 189μts/cm to 405 μs/cm,and then maintained a stable upward trend,pH showed a downward trend after the peak.The relationship between water temperature and conductivity,pH was positively correlated with the water temperature in the Huobadong spring,which showed the peak during the period.After 10 hours of rainfall duration,pH and electrical conductivity showed a downward trend.Under the condition of weak rainfall,the Caihuaqing spring and Huobadong spring presented small amplitudes of physicochemical variations.At the early,middle and late stages of rainfall,pH and conductivity of the two springs appeared dilution effect curves.