Stable isotope studies of precipitation and river water in the Lake Biwa basin, Japan

✍ Scribed by Makoto Taniguchi; Tomoe Nakayama; Norio Tase; Jun Shimada

• Publisher: John Wiley and Sons
• Year: 2000
• Tongue: English
• Weight: 363 KB
• Volume: 14
• Category: Article
• ISSN: 0885-6087
• DOI: 10.1002/(sici)1099-1085(20000228)14:3<539::aid-hyp953>3.0.co;2-l

✦ Synopsis

The d 18 O and dD in 17 river waters ¯owing into and out of Lake Biwa, the lake water itself and precipitation at 11 locations in the Lake Biwa basin were observed from October 1996 to September 1997, to evaluate the origin of river waters and the eect of irrigation water from the lake on the river waters ¯owing into Lake Biwa. The regional dierence and altitude eect of the stable isotopes in precipitation and river water were found in the basin. The d 18 O in the rivers which are located in the eastern and the southern areas in the basin is heavier than that of the other rivers, due to the eect of irrigation for the nearby paddy ®elds. Evaporation from Lake Biwa and the in¯ow rate into the lake estimated from the d 18 O balance agree well with the results of previous studies which used water balance methods. The stable isotopes can enable us to evaluate not only water balance but also the origin of the water and the water ¯ow system.