Influence of Seasonal Change of Forest Floor Cover Percentage on Water Discharge and Suspended Load from Watershed

在田泽山斗平的森林坡面和林下植被因鹿的采食而贫瘠的流域，监测了土壤侵蚀率、地表径流、森林地面覆盖率、穿透雨、排水量、浊度等。 获得了以下结果。(1)阐明了森林地被覆盖率季节变化对坡面径流和土壤侵蚀速率的影响及其机理。(2)阐明了侵蚀速率与悬移质之间的关系，以及坡面径流量与河流流量之间的关系。 （3）提出了鹿的采食减少林下植被和森林覆盖率变化对径流量和悬移质季节变化和年际变化影响的估算方法。

Soil erosion rate, overland flow, forest floor cover percentage, throughfall, water discharge, turbidity, etc. were monitored on the forest slope and watersheds with an understory impoverished by the feeding of deer in Doudaira, Tanazawa Mountains. Following results were obtained. (1) The mechanism and influence of seasonal change of forest floor cover percentage on overland flow and soil erosion rate were clarified. (2) The relationship between erosion rate and suspended load, and the relationship between overland flow and water discharge in the streams were clarified. (3)The estimation methods for influence of decrease in understory by the feeding of deer and change in forest cover percentage on the seasonal change and annual change in water discharge and suspended load were proposed.