ろ紙吸光法による清流河川の推定透視度に関する研究

Abstract

To conserve clean water it is important to monitor slight change of its water quality. Filter Absorbance Method is a method of filtering the river water and measuring a filter by the spectrophotometer with the integrating-sphere attachment. The Absorbance curve of the filter shows the character of particle matter in water. This method is easy, cheap, and quick to measure, moreover it is suitable for checking slight water quality change. 36 rivers, which are the best BOD in the survey of 1997 in Japan, are investigated each month from November in 1998 to January in 1999. Transparency (T) was surveyed on site and Total Absorbance (TA), which is calculated from the absorbance curve as an integral value between 400 nm to 800 nm, is measured by the spectrophotometer at an laboratory. The relation between TA and T was surveyed in the condition of 4 different filtering volume, 100 cc, 200 cc, 300 cc, and 400 cc. The relation between TA and T is expressed by the following equations.