高原河流溶解氧变化规律研究

Study on the Variation of Dissolved Oxygen in the Plateau River

文章以雅鲁藏布江第二大支流尼洋河为例,根据尼洋河干、支流汛期的溶解氧实测资料,分析了高原河流丰、平、枯3个时期溶解氧受海拔、气压、水温、电导率、支流汇入及水利工程影响的变化规律。尼洋河干流丰水期溶解氧浓度和饱和度最低,枯水期最大,干流溶解氧指标达到Ⅱ类及以上标准,水体污染较小;影响溶解氧的主要因子为海拔、气温、气压、水温、电导率;溶解氧饱和度总体变化趋势随海拔降低逐渐增大;随气压增大溶解氧饱和度增加,随着水温升高溶解氧饱和度总体表现升高趋势,溶解氧饱和度随着电导率减小而增加,同一时期,尼洋河支流溶解氧饱和度高于干流;在水利工程位置均出现了溶解氧值的突变。

This paper takes Niyang River,the second largest tributary of the Yarlung Zangbos as an example.Based on the measured data of dissolved oxygen in flood season of Niyang River,the variation law of dissolved oxygen affected by elevation,air pressure,water temperature,electrical conductivity,tributary confluence and water conservancy engineering in high water period,normal water period and dry period was analyzed.The results showed that the dissolved oxygen concentration and saturation are the lowest in the high water period of Niyang River and the largest in the dry season.The dissolved oxygen index of the main stream reaches class Ⅱ and above,and the water pollution is relatively small.The main factors affecting the dissolved oxygen are altitude,temperature,pressure,temperature,conductivity.With the increase of pressure,the dissolved oxygen saturation increases.As the water temperature increases,the dissolved oxygen saturation shows an increasing trend,and the dissolved oxygen saturation increases with the decrease of conductivity.At the same time,the oxygen saturation is higher than that of the River tributaries.There is a mutation of dissolved oxygen in the water conservancy project.