Conservation of Water Related Environment of Watersheds with Agriculture and Forestry Landuse in Cold Region.

在本项目中，研究人员对冷地区的水和物质循环、水使用和农村地区管理、可持续农业和环境保护进行了研究。1）对西南北海道舒布托河盆地、西南部的农业和森林地区的土地使用和河流水质量之间的关系进行了调查。当含水量不足时，含水量包括农业陆地显示出对水质量的高度集中; 2）在雪梅尔特周期中使用主要成分分析进行调查时，水质量变化的特征; 3）循环irrigation系统对水质量和物质平衡的影响被测试在Tsugaru， Aomori的Lowland地区。不仅仅是水的输出，但也是给下莱赫湖和河流的电子物质的输出减少到循环的扭曲.（4）T-N的区域特征，T-P和分散的SiO-D22-D2集中于北海道河水域，雪融化期被调查在与陆地用途和每个水类型的土壤结合处。关于雪和雪熔水的组成的研究已在北海道北部森林地区进行了测试。这表明，离子成分很容易在雪融化期的早期阶段从雪中释放出来。

In this project, researches were made on water and material circulation, water use and rural area management, sustainable agriculture and environmental conservaion for the agricultural and forest area in cold regions.1) Relation between land use and river water quality was investigated on Shubuto river basin, southwestern Hokkaido. Watershed including agrictural land shows high concentrations on water quality when the amount of retained water in the watershed gets less.2) Characteristics of changes in water quality during snowmelt period were investigated using the principal component analysis.3) The effect of circulating irrigation system to the water quality and material balance were examined in lowland area of Tsugaru, Aomori. Not only the output of water, but also the output of eutrophic substances to the lakes and rivers of lower raehes were reduced due to circulating irrigation.4) Regional characteristics of T-N, T-P and dissolved SiOィイD22ィエD2 concentration in river water of Hokkaido during snow melt period was investigated in conjunction with land use and soil type of each watersheds.5) Study on ion composition of snow and snowmelt water from bottom of snow cover was tested in the forest area of northern Hokkaido. It was shown that the ion component are easily released from the snow at the early stage of snowmelt period.