Research for chemical reaction and transportation of chemical elements as a successive reaction system in forest ecosystem

酸性物质的沉积会影响森林生态系统的养分循环。本研究的目的是将养分循环系统视为雨水与叶片、茎和土壤依次接触的连续化学反应系统，并评价酸性物质的作用。在本研究中，用HINOKI进行了两个实验。首先是连续的野外观察，以确定干沉积对叶片表面淋滤过程的影响。结果表明，干沉降会影响阴离子在叶片表面的行为，并可能增强阴离子在叶片表面的渗透能力。第二项试验是在HINOKI林分利用人工雨水进行大规模降雨试验。雨水的pH值从6.8调整到3.2。研究了秋水、茎流和土壤水分中化学元素的浓度变化。结果发现，钾离子从叶和茎中浸出，钙离子被叶和茎吸收。钠离子与树木表面的相互作用很小。另一方面，无机阴离子在叶片、茎和土壤中的浓度变化没有发现。这表明有机阴离子的存在在体系中是重要的。

Nutrient cycle in forest ecosystem would be affected by deposition of acidic materials. The purpose of this study were to consider the nutrient cycle system as a successive chemical reaction system through a flow process of rain water contacting with leaves, stem and soil, successively, and to evaluate the effect of acid materials. In this study, two experiments were performed by using HINOKI.The first was the continuous field observation to determine the effect of dry deposition on leaching process from leave surface. As the results, it was recognized that the behaviors of anions on leaf surface were affected by dry deposition and their penetration through leaf surface might be enhanced. The second experiment was a large-scale rain fall experiment using artificial rain water in HINOKI forest stand. pH of rain water were adjusted to 3.2 of 6.8. The concentration change of chemical elements in through fall, stem flow and soil water were pursued. As the results, it was found that potassium ion is leached from leaves and stem and calcium ion is uptake into leaves and stem. Sodium ion has little interaction with the surface of tree. On the other hand, the change in concentration of inorganic anions through leaves, stem and soil was not found. It is suggested that the existence of organic anions is important in the system.