Evaluation for future and present condition on a roll of forest as nonpoint source of nitrogen for the Seto Inland Sea

2017 Fiscal Year Final Research Report

• Project/Area Number: 15K00570
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Research Field: Environmental impact assessment
• Research Institution: Osaka Institute of Technology
• Principal Investigator: Komai Yukio 大阪工業大学, 工学部, 教授 (00446808)
• Research Collaborator: KUNIMATSU Takao
• Project Period (FY): 2015-04-01 – 2018-03-31
• Keywords: 瀬戸内海 / 森林 / 渓流水 / 窒素濃度 / 窒素比流出負荷量 / 分布型流出モデル / IFAS / シミュレーション

Outline of Final Research Achievements

The specific load and the amount of nitrogen flowing into the Seto Inland Sea from the forest area were estimated by using nitrogen concentration in mountain streams, which were not affected by any artificial pollution and the specific discharge by the distributed runoff model constructed by IFAS of ICHARM, Public Works Research Institute.
The specific load of nitrogen in forest area of the Seto Inland Sea watershed was calculated 5.8 kg/ha/year as average value for the two years from 2013 and 2014. This result showed that the unit load of nitrogen by the Ministry of Environment, which was 6.9 kg/ha/year, was 1.1 times larger than the specific load of nitrogen based on actual data. Therefore, it was suggested that the amount of nitrogen loadings by the Ministry of Environment was over estimated.

Free Research Field

水環境