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一般研究成果リスト

Detail of Grant Awarded General Researches

Project

A New Development in the Comprehensive and Concurrent Survey of the Tama River Basin Water Quality by Citizens and Children--—Measurement of Electric Conductivity, Nitrate Nitrogen and Phosphate-Phosphorus

General
Research
No.219
Principal
Investigator
Isami Watanabe
Affiliation Chairman, Subcommittee on Preservation and Creation of the Water Environment, The Beautiful Tama River Forum
Research
Summary

The Beautiful Tama River Forum has measured the air temperature, water temperature and chemical oxygen demand (CODMn) at 75 different sites (55 sites at first) concurrently from the upper to the lower reaches of the Tama River with the help of citizens and children of the Tama River basin. This comprehensive survey had been done five times between June 2008 and June 2012. We plotted the survey results on the water quality map of the Tama River basin and posted it on our website. We also distributed the map to elementary and junior high schools, local governments and organizations in the basin to provide information regarding the water quality status of the Tama River.


In the FY2013-2014 survey, we have added the measurement of electric conductivity, an indicator for the total quantity of inorganic ion, nitrate nitrogen, contained abundantly in domestic effluents, and phosphate-phosphorus to the measurement of CODMn, an indicator for water contamination by organic materials, with the aim of establishing a system for the water quality assessment of the Tama River.


1. When carrying out a water quality survey, a basic understanding of the survey is essential in order to collect accurate data. For this reason, we created an easy-to-understand, illustrated textbook titled "How to Measure the Water Quality around You" teaching citizens and children how to conduct a water quality survey.

2. This research found that an important point in conducting a water quality survey is to record where samples were taken, and thus the sampling points were identified by latitude and longitude.

3. According to the result of the water quality survey of the upper-lower reaches of the Tama River, the water quality from the Tamagawa Joryu (Upper Reaches) Water Reclamation Center to the middle/lower reaches was largely affected by treated sewage effluents. In the lower reaches, some ammonium nitrogen and nitrite nitrogen were found. It will be necessary to monitor them from now on.

4. We have also plotted the data of electric conductivity and nitrate nitrogen on the water quality map of the Tama River, and distributed it to provide information to elementary and junior high schools, local governments and organizations in the Tama River basin.


Collaborators

Kenji Ito, Chie Oikawa, Katsuya Otsuka, Takashi Kasakura, Keiko Shiono, Chizuna Takada, Chikayoshi Hattori, Yuri Higuchi, Shuichi Maeda, Kikuko Matsui

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