Yatsugatake walk vol.7

a perfect guide of Yatsugatake area for tourists


Yatsugatake, southern Alps Sake Tour
The man who measures the rain fall in the forest 
(P.58-59)

The Yatsugatake and Southern Alps area produces a wide variety of delicious sake including Japanese sake, whiskey, wine, beer, and Shochu.
In order to produce delicious sake, you need a location rich with spring water. We visited a young researcher at the "place of the beginning", the source where that famous water is found.

Researcher at the Yamanashi Prefectural Forest Research institute
Mr. Mitsuru Hirose
Born: 1986   Since his school days, he was interested in Rock and mountain climbing, and research in the higher mountain elevation range. His favorite liquors are beer, whiskey, and Japanese sake.

 

The forest where the famous spring water origines

 

The rain that falls in the mountains becomes rivers, that in the end merges with the ocean... This is why I thought forests are important, but Mr. Hirose explained that " Not all rain that falls in the forests reaches the ground  " His specialty " Forest hydrology " is a sub-discipline of " hydrology " focusing on the dynamics of water circulation and movement, the use of water resources, the impact humans have on its environment, and especially also the beginning of rivers, in woodland areas. His research area is at the foot of Mt. Mizugaki in Hokuto city. Inside the forest, he has several hand-made surveying instruments installed.  Simply put, they measure the amount of rain that fell.

"Not all rain in the forest reaches the ground" means that some of the rainwater sticks to the leaves and evaporates. Water that does not reach the ground is not added to the water resources.
There are three main routes for rainwater to reach the ground: between the gaps of trees and shrubs, dripping from the leaves, and water that flows down the trunk of the trees. Mr. Hirose measures the amount of rain and studies how much of it flows into the rivers.



The amount of rainwater varies depending on the type of tree; evergreen or deciduous, conifer or broadleaf, and on the height of the tree, the thickness of the trunk and so on. In addition, the amount of water that flows into the river varies depending on whether the ground is exposed, the leaves on the ground, and how much undergrowth there is. "In recent years damage by deer have become a problem, giving concern that this causes a change in some places."

The fun of facing complexity

“Closely packed coniferous trees cannot store water. Thinning will improve undergrowth which will decrease the amount of water falling on the floor. However, it will increase the amount of water that will evaporate from the leaves. Anyway, nature is complex with many intertwined elements. This is interesting”, says Mr. Hirose with a glowing face. "Coniferous trees are often seen as hostile, but they also become sacred trees, or take the Yakushima cedar, don't you think it is a strong tree? I think it is important to consider how to use them."
The famous spring water is one of the assets of the Yatsugatake and southern Alps area, and it is the job of the researcher to protect this by carefully considering each event.