Study on dry deposition of sulfur dioxide to the Chinese desert soil and estimation of its dry removal from the atomosphere

为了获得估算SO_2在中国荒漠和黄沙土壤上干沉降对大气中SO_2去除量的基础数据，我们研究了上述土壤和几种模式土壤对含微量SO_2、NO_2和HNO_3的实验气体的暴露。通过上述暴露试验等获得的结果如下：1）完成了我国荒漠黄沙土的元素分析。结果表明，土壤颗粒酸度与Ca含量有密切关系。2）SO_2在我国荒漠和黄砂土壤中的干沉降速率取决于土壤的碱度和暴露气体的湿度; 3）HNO_3在各种土壤中的干沉降速率与SO_2的干沉降速率基本一致。而NO_2则远低于SO_2。4）S（VI）/S（IV）沉积在沙漠、黄沙、随着暴露气体湿度的增加和模拟日光照射时间的延长，5）将人工肺应用于低浓度SO_2和HNO_3气体的收集。6）为了估算SO_2的去除量，对人工肺进行了实验研究2在中国沙漠和黄砂土壤中的干沉降作用，有待于进一步研究。

In order to obtain the fundamental data to estimate the removal amount of SO_2 from the atmosphere by its dry deposition on the Chinese desert and yellow sand soils, we investigated the exposure of the above soils and several model soils to the experimental gases containing trace level of SO_2, NO_2, or HNO_3. The results obtained by the above exposure experiments etc, were summarized as below.1) Elemental analyses for desert yellow sand soils in China were achieved. The results indicated the intimate relation of acidity of soil particles with content of Ca. It suggests the relation of soil acidity with the frequency of acid rain appearence.2) Dry deposition velocity of SO_2 to desert and yellow sand soils in China depended on soil alkalinity and humidity of exposure gas.3) Dry deposition velocity of HNO_3 to various soils was similar level of that of SO_2. While, that of NO_2 was much lower than that of SO_2.4) S(VI)/S(IV) deposited on desert, yellow sand, and model soils was increased with increase in the humidity of exposure gas and the irradiation time with a simulated sun-light (black-light).5) The artificial lung was applied to collection of low concentration SO_2 and gaseous HNO_3.6) In order to estimate the removal amount of SO_2 from the atmosphere by its dry deposition on the Chinese desert and yellow sand soils, further investigation is needed.