Japan Geoscience Union Meeting 2018

Presentation information

[EE] Oral

A (Atmospheric and Hydrospheric Sciences) » A-HW Hydrology & Water Environment

[A-HW20] Materials transport and nutrient cycles in watersheds; Human and climate impacts

Sun. May 20, 2018 3:30 PM - 5:00 PM 105 (1F International Conference Hall, Makuhari Messe)

convener:Mitsuyo Saito(Graduate School of Environmental and Life Science, Okayama University), Shin-ichi Onodera(Graduate School of Integrated and Arts Sciences, Hiroshima University), Takahiro Hosono(熊本大学大学院先導機構, 共同), Adina Paytan(University of California Santa Cruz), Chairperson:Paytan Adina(University of California, Santa Cruz)

4:00 PM - 4:15 PM

[AHW20-08] Estimation of lacustrine groundwater discharge into Biwa Lake

*Kunyang Wang1, Mitsuyo Saito2, Shin-ichi Onodera1, Fandy Tri Admajaya1, Syuhei Ban3, Noboru Okuda4, Yuta Shimizu5 (1.Hiroshima University, 2.Okayama University, 3.The University of Shiga Prefecture, 4.Research Institute for Humanity and Nature, 5.National Agriculture and Food Research Organization)

Keywords:LGD, lacustrine groundwater discharge, Biwa Lake, SWAT Model

The quantification of lacustrine groundwater discharge (LGD) in water is one of the most important indicators of water cycle in lakes by carrying large nutrient loads. The Yasu River is one of the important water sources of Biwa Lake. This paper using Geographic Information System technology, and based on the analysis and prediction of the land use change in Yasu River basin. The water balance was simulated using the Soil and Water Assessment Tool (SWAT2012). Model calibration and uncertainty analysis were performed with sequential uncertainty fitting (SUFI-2). The correlation coefficient and the Nash–Sutcliffe coefficient is higher than 0.50. The results shown that total groundwater accounted for 41.77% of the rainfall and 62.82% of them are shallow groundwater. At the same time, nitrogen and phosphorus are also released to the river with groundwater, continuous impact on the water and water quality of the Biwa Lake.