Ecosystem Services assessment on water environment under population decreasing area in forestry and paddy fields watershed

The Ecosystem Services of the water environment in the mountainous agricultural area in population decreasing watershed was assessed by the observation of water quality and SWAT model analysis. The study area was Ikeda town, Fukui prefecture, Japan. The results for nitrogen and phosphorus were shown that it was difficult to say that rice paddy agriculture is an explicit source of pollution to the river and the aquatic environment. SWAT model output was shown that runoff rate was high and the majority of the annual flow was discharged as groundwater, especially during snowfall and snowmelt season.