用洁净水体监测大气沉降物污染的新方法研究

Study on the New Method for Observing the Pollution of Clean Water by Atmospheric Deposition

使用标本缸做为采样装置盛放去离子水露天连续放置1 a,观测水体受到大气干、湿沉降物和沙尘暴降尘的污染状况。期间每隔5~10 d从缸内抽取一定体积的水样,分析其中的水溶性离子和B、Ba、Be、Cd、Cu、Co、Fe、Mo、Mn、Ni、Pb、Sb、Ti、Tl、V、Zn等16种金属元素,除Be在部分样品中被检出外,其余15种元素的检出率均达到100%。在水体中的浓度总体呈明显富集和逐渐升高趋势。从直观和微观的角度阐述大气干、湿沉降物和沙尘暴降尘对洁净水体的污染过程。

For the experiment,we use specimen jar as sampling device. A certain volume of deionized water fills with the jar, which is kept continuously for a year in the open air,with a view to observing the pollution status of such clean water due to dry and wet fallouts in the atmosphere and sandstorm dust fall. During the period,some volumetric water sample is collected every five to ten days and then is used to analyze 14 water-soluble ions and many metallic elements. Simultaneously,water should be supplemented to make up for the reduced amount as a result of evaporation and sampling. The tested ions and 16 metallic elements like B,Ba, Be,Cd,Cu,Co,Fe,Mo,Mn,Ni,Pb,Sb,Ti,T1,V and Zn are found 100% in detection rate with the exception of Be,whose concentration is detected in some samples. Their concentrations in water show obvious enrichment and are inclined to progressive rising. We can both intuitively and microcosmically get in-depth understanding about how the dry and wet precipitum in the atmosphere and sandstorm dust fall are contaminating the clean water. What＇s more,it has practical implications to us with regards to investigating the extent of pollution on surface water and inland lakes,deposition flux of elements as well as main input ways for soil elements into farmland ecosystem.