title: 2020s scenario analysis of nutrient load in the Mekong River Basin using a distributed hydrological model.
abstract: A distributed hydrological model, YHyM, was integrated with the export coefficient concept and applied to simulate the nutrient load in the Mekong River Basin. In the validation period (1992-1999), Nash-Sutcliffe efficiency was 76.4% for discharge, 65.9% for total nitrogen, and 45.3% for total phosphorus at Khong Chiam. Using the model, scenario analysis was then performed for the 2020s taking into account major anthropogenic factors: climate change, population, land cover, fertilizer use, and industrial waste water. The results show that the load at Kompong Cham in 2020s is 6.3 x 10(4)tN a(-1) (+13.0% compared to 1990s) and 4.3 x 10(3)tP a(-1) (+24.7%). Overall, the noticeable nutrient sources are cropland in the middle region and urban load in the lower region. The installation of waste water treatment plants in urban areas possibly cut 60.6%N and 19.9%P of the estimated increase in the case without any treatment.
authors.affiliation: Department of Civil Engineering, Tokyo Institute of Technology, Tokyo 152-8552, Japan. yoshimura.c.aa@m.titech.ac.jp
authors.forename: Chihiro
authors.initials: C
authors.lastname: Yoshimura
authors.forename: Maichun
authors.initials: M
authors.lastname: Zhou
authors.forename: Anthony S
authors.initials: AS
authors.lastname: Kiem
authors.forename: Kazuhiko
authors.initials: K
authors.lastname: Fukami
authors.forename: Hapuarachchi H A
authors.initials: HH
authors.lastname: Prasantha
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Ishidaira
authors.forename: Kuniyoshi
authors.initials: K
authors.lastname: Takeuchi
mesh_terms: D011232:Chemical Precipitation; D002681:China; D017753:Ecosystem; D004784:Environmental Monitoring; D005502:Food / Q000706:statistics & numerical data; D008962:Models, Theoretical; D009584:Nitrogen / Q000032:analysis* / Q000378:metabolism; D010758:Phosphorus / Q000032:analysis* / Q000378:metabolism; D045483:Rivers / Q000737:chemistry*; D014872:Water Movements; D014874:Water Pollutants, Chemical / Q000032:analysis*; D014881:Water Supply
chemical_list: D014874:Water Pollutants, Chemical; D010758:Phosphorus; D009584:Nitrogen