祁连山大野口流域降水-土壤水-河川来水相关性分析

目的]对祁连山大野口流域降水、土壤水和河川来水的相互关系进行分析,旨在为掌握流域水文过程及河川径流形成机理提供理论支持。方法]运用祁连山大野口流域18a人工和2a自动监测的38万多个数据,采用特征参数算法、相关和多元回归等方法进行分析。结果](1)降水量、空气湿度和河川径流18a平均为374.06mm,60.91%,166.73mm。降水的44.57%最后形成了河川径流。降水和河川径流上升率均为18mm/10a,空气湿度上升率约为1.2%/10a。(2)降水、空气湿度、土壤水、河川来水在一年中的变化步调基本一致。(3)在森林高度范围内,距地面越高,空气湿度越大,受降水的影响越小;在0—80cm深度范围内,土壤越深,降水对土壤水分的影响越小。(4)降水、空气湿度、土壤水、河川来水的相互关系较紧密,建立的回归模型可预测降水、土壤水、河川来水量变差的95.2%,88.8%,97.6%,准确率可达93.4%,84.6%,96.7%。结论]降水、土壤水、河川来水的分配比例可量化和可调控流域水资源需水量方面的分配比例;将人工观测和自动监测数据同化分析,解决了流域生态水文过程研究中的数据短缺问题。

Correlation Analysis of Precipitation, Soil Water and River Water in Dayekou Basin of Qilian Mountains

Objective] Correlations among precipitation, soil water and river water were analyzed in Dayekou Basin of Qilian Mountains in order to explore the ecological and hydrological processes of basin and river runoff formation. Methods] More than 380 thousand data observed artificially for 18 years and obtained automatically for 2 years were processed using methods of characteristic-parameters algorithm, correlation analysis and multiple regression. Results] (1) The annual precipitation, air humidity and river runoff depth averaged over the 18 years'' artificial observations were 374.06 mm, 60.91% and 166.73 mm, respectively. The river runoff accounted annually for 44.57% of the precipitation. The precipitation, air humidity and river runoff all showed rising trends with average rates of 18 mm/10 a, 1.12%/10 a and 18 mm/10 a, respectively. (2) The precipitation, air humidity, soil moisture and river runoff varied intra-annually in step. (3) With the height increase from forest ground, the influence of precipitation on air humidity decreased; In 0-80 cm soil profile, with the increase of soil depth, the influence of precipitation on soil moisture also decreased . (4) The relationship between rainfall, air humidity, soil water, river water more closely, the regression model among precipitation, air humidity, soil moisture and river runoff can interpreted the 95.2% and 88.8% and 97.6% variances of precipitation, soil moisture and river runoff, respectively, and with averaged prediction accuracies of 93.4%, 84.6% and 96.7%. Conclusion] The proportional allocation among precipitation, soil water, river water could be quantified and regulated. The data acquiring methods of manual observation and automatic monitoring could well solve the ecological and hydrological processes research in river basin.