Fields Surveys in the Forests Affected by Acid Snow and Rain

对受酸雪雨影响的森林进行实地调查

基本信息

批准号：
07680575
负责人：
TAGUCHI Yoji
金额：
$ 1.28万
依托单位：
NIIGATA UNIVERSITY
依托单位国家：
日本
项目类别：
Grant-in-Aid for Scientific Research (C)
财政年份：
1995
资助国家：
日本
起止时间：
1995 至 1996
项目状态：
已结题

来源：
https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-07680575/
关键词：
Acid Snow and Rain pH Anions Forest Soil Acidification Dissolved Aluminum and Phosphorous Acid shock 森林(スギ)

项目摘要

From the measurement of the pH levels and the analysis of components of the fallen snow in Niigata Prefecture, the characteristics of the snow were almost the same as those observed in the snow along the coast of the Sea of Japan from Shimane to Akita Prefecture. Using the multiple regression analysis method, the cause for the lower value of pH in the fresh snow has become evident as a result of mainly the sulfate ions contained in the snow.From some field surveys in the forests at Niigata Prefecture, few withered trees due to acid snow and rain have been found, although the possibility such damaged trees should exist. Cedar, a kind of evergreen tree, has the capability to include more amounts of acidic deposits than the broadleaf trees because of the cedar's rougher trunk and evergreen leaves. While, the flow-down water of melted snow along the trunks of broadleaf trees was neutralized or relaxd with the basic substances released from the trees.The influence of acid rain and snow on soil is not such a serious problem at the present time. However, from the results of the pH measurement of soil and the amounts of leached-elements from the soil, 35% of 113 soil samples mostly gathered in the Niigata Prefecture was estimated to be already acidified.There is a remarkable tendency for the hydrogen ion concentration in snowmelt water in the early spring to be higher than that in the late spring. The fresh fallen snow on the ground is compressed by repeated dissolution and crystallization and forms icy granular snow. The repetition causes sulfate, nitrate and chloride ions to be concentrated near the surface of the icy granular snow. Some laboratory experiments were performed to examine this concentration phenomenon by the formation of spherical ice.

从对pH值的测量和尼加塔县落雪的成分分析，雪的特征几乎与从西马内斯到阿基塔县的日本海沿海中观察到的那些相同。使用多重回归分析方法，由于主要是雪中包含的硫酸盐离子，新鲜雪中pH值较低的原因变得显而易见。从Niigata县的森林中的一些现场调查，很少有枯萎的树木尽管存在这种受损的树木的可能性，但已经发现了酸雪和雨水。雪松是一种常绿的树，由于雪松的粗糙树干和常绿的叶子，比阔叶树相比，有能力包括更多的酸性沉积物。而沿着阔叶树的树干融化的积雪的流动水被中和或放松，从树木中释放出的基本物质。目前，酸雨和雪对土壤的影响并不是一个严重的问题。但是，从土壤的pH值和从土壤中的浸出元素的量的结果来看，据估计，大多数收集在尼加塔县中的113个土壤样品中有35％已经被酸化了。早春在融雪水中的浓度高于春末。通过反复溶解和结晶并形成冰冷的颗粒状雪，地面上的新鲜降雪被压缩。重复会导致硫酸盐，硝酸盐和氯离子浓缩在冰冷的颗粒积雪的表面附近。进行了一些实验室实验，以通过球形冰的形成来检查这种浓度现象。