[O04-P48] A study of the fluctuations in the water level of Kohama pond
Keywords:fluctuations, pond, Electric Conductivity
Kohama pond in Rakujuen in Mishima city is a pond where spring water collects, and it has had a close relationship with people living near it for a long time.
At present, however, there are lots of questions that are yet to be defined, such as the full-water period and seasonal water level changes.
In this study we surveyed and considered its fluctuations in the water level in terms of weather, water veins, and water quality.
We made a graph focused to the term after typhoon 19 hit to reveal the relation between precipitation and the fluctuations. As a result, we concluded that Gotenba city’s precipitation does not have any direct relation with it for the reason that there is no correlation between them from Nov. 17 to Nov. 18, and the distance from Gotenba city to Mishima city is about 32.9 km.
We then considered whether the Great East Japan earthquake made its average water level rise.
We found the importance of caution in using the data of Kohama pond because the spring water spreads when the water level is over 0m.
The differences of Electric Conductivity (EC) is due to the time when lava was made. In general, the flow velocity of the new lava groundwater is faster than the old one, and the amount of ions dissolved from lava is in proportion to the flow of time.
Because of these, the Hakone and Ashitaka lava water veins, which are known to be old-class water veins, both showed high EC.
Therefore, we inferred that the water vein of the water purifying plant in Izushimada whose EC was as low as 146, is the same as that of Kohama pond whose EC was about 159.
Acknowledgment:
Yusuke Suzuki (Izu Peninsula Geopark Promotion Council)
References:
Open data of Mishima city, https://www.city.mishima.shizuoka.jp/ipn017227.html;
Japan Meteorological Agency, http://www.jma.go.jp/jma/menu/menureport.html;
The data of water purifying plant in Izushimada
At present, however, there are lots of questions that are yet to be defined, such as the full-water period and seasonal water level changes.
In this study we surveyed and considered its fluctuations in the water level in terms of weather, water veins, and water quality.
We made a graph focused to the term after typhoon 19 hit to reveal the relation between precipitation and the fluctuations. As a result, we concluded that Gotenba city’s precipitation does not have any direct relation with it for the reason that there is no correlation between them from Nov. 17 to Nov. 18, and the distance from Gotenba city to Mishima city is about 32.9 km.
We then considered whether the Great East Japan earthquake made its average water level rise.
We found the importance of caution in using the data of Kohama pond because the spring water spreads when the water level is over 0m.
The differences of Electric Conductivity (EC) is due to the time when lava was made. In general, the flow velocity of the new lava groundwater is faster than the old one, and the amount of ions dissolved from lava is in proportion to the flow of time.
Because of these, the Hakone and Ashitaka lava water veins, which are known to be old-class water veins, both showed high EC.
Therefore, we inferred that the water vein of the water purifying plant in Izushimada whose EC was as low as 146, is the same as that of Kohama pond whose EC was about 159.
Acknowledgment:
Yusuke Suzuki (Izu Peninsula Geopark Promotion Council)
References:
Open data of Mishima city, https://www.city.mishima.shizuoka.jp/ipn017227.html;
Japan Meteorological Agency, http://www.jma.go.jp/jma/menu/menureport.html;
The data of water purifying plant in Izushimada