Abstract
Jozankei Experimental Watershed (JEW), located in a national forest on the outskirts of Sapporo, Hokkaido, Japan, was established in 1987 for the purpose of forest hydrological research in cold, snowy regions. The study site consists of two adjacent smaller watersheds, called Shigure-Ichinosawa and Shigure-Ninosawa. Long-term surveys of precipitation and stream runoff in both watersheds have been conducted. Daily precipitation and runoff data from 1991 to 2012 have already been published. This report describes daily precipitation and runoff data for the five-year period from 2013 through 2017. There were some events to note during this period. High-intensity precipitation of 76.5 mm per day coincided with peak snowmelt-runoff on April 7, 2013, and a large amount of sediment flowed into the sediment reservoirs. At this time, an overflow occurred at the gauging weir in Shigure-Ninosawa. Therefore, we carried out dredging from February 21 to March 3, 2014. Some long-term precipitation data are missing from the observation period. Stand-wither became noticeable during this period. The causes of damage within the watersheds were considered to include the increase in DBH-H ratio and the increase in the Yezo deer population.
