Study on the measurement of deposition of small-sized droplets in the atmosphere

众所周知，由于人类活动，雾比雨污染更严重，酸性更强，影响森林环境等生态系统。然而，通过测量由雾滴沉积引起的“穿透降落”和“树干降落”，间接估计了与雾滴沉积相关的输送到林木的污染物的量，并且没有直接测量该量。在这项研究中，我们开发了一种方法，用于测量的沉积通量的雾水，Fw，与聚合物吸水剂，通过进行基础实验，在釜石矿，这提供了一个稳定的雾的大型长竖井。组分的沉积通量Fi可以通过Fi=FwCi计算，其中Ci是液滴相中组分的浓度。基于这一想法，我们进行了实地观察，在山。2002年夏天在日本中部的赤城，测量Fw并确定收集的雾中离子种类的浓度 ...更多信息 水在这些实验中，通过切割一片高吸水性聚合物并通过悬挂到场地周围的树木和模拟圣诞树的塑料针叶树上而暴露于雾中来制备模拟针叶和落叶的人造叶。结果发现，模拟叶片的Fw值在迎风侧大于背风侧。类似的Fw值从针叶和落叶，挂在树荫下。这表明沉积通量与叶片形状无关。另一方面，收集的雾水的酸度高，达到pH=2.7。主要离子种类为H+、NH 4+、SO 42-和NO3-。然而，当pH超过4时，H+不是重要组分。9月5日，H ~+、NH ~（4+）、SO_（42-）和NO_（3-）浓度最高，雾引起的总沉降量分别为0.22、0.07、0.06和0.04 meq/m ~ 2。为了评估雾在总沉降中的作用，需要进行长期观测，其中不仅包括与雾有关的酸性组分的沉降量的测量，而且还包括雨。少

It is known that fogs are more polluted and acidic than rain due to human activities, affecting ecosystems such as forest environments. However the amount of pollutants transported to forest trees associated with the deposition of fog droplets has been indirectly estimated through the measurement of 'through fall' and 'stem fall', caused by deposition of fog droplets, and there has been no direct measurement on this amount. In this study, we developed a method for the measurement of the deposition flux of fog water, Fw, with a polymeric water absorbent, by conducting basic experiments in a large-scale long vertical shaft in Kamaishi Mine, which afforded a steady fog. The deposition flux of a component, Fi, can be calculated through Fi=FwCi, where Ci is the concentration of the component in the droplet-phase. Based on this idea, we made field observations at Mt. Akagi in central Japan in the summer of 2002, to measure Fw and determine the concentrations of ionic species in collected fog … More water. In these experiments, artificial leaves imitating coniferous and deciduous leaves were prepared by cutting a sheet of a super absorbent polymer and exposed to fogs by hanging to trees around the site and a plastic coniferous tree imitating a Christmas tree. As a result, Fw values of the imitation leaves found to be larger at the windward side than the leeward side. Similar Fw values were obtained from the coniferous and deciduous leaves, hung to the shades of the trees. This suggests that the deposition flux is independent of the shape of leaves. On the other hand, the acidity of collected fog water was high, attaining pH=2.7. Dominant ionic species were H+, NH4+, SO42- and NO3-. However, H+ was not an important component when pH exceeded 4. The amounts of total deposition due to fog were 0.22, 0.07, 0.06 and 0.04 meq/m2 in a day, for H+, NH4+, SO42- and NO3- in September 5, when the concentrations of the aqueous species were highest. To evaluate the role of fogs in total deposition, long term observations are needed, in which the measurement of the deposition amount of acidic components associated with not only fogs but also rain is included. Less