title: Pesticide transport simulation in a tropical catchment by SWAT.
abstract: The application of agrochemicals in Southeast Asia is increasing in rate, variety and toxicity with alarming speed. Understanding the behavior of these different contaminants within the environment require comprehensive monitoring programs as well as accurate simulations with hydrological models. We used the SWAT hydrological model to simulate the fate of three different pesticides, one of each usage type (herbicide, fungicide and insecticide) in a mountainous catchment in Northern Thailand. Three key parameters were identified: the sorption coefficient, the decay coefficient and the coefficient controlling pesticide percolation. We yielded satisfactory results simulating pesticide load dynamics during the calibration period (NSE: 0.92-0.67); the results during the validation period were also acceptable (NSE: 0.61-0.28). The results of this study are an important step in understanding the modeling behavior of these pesticides in SWAT and will help to identify thresholds of worst-case scenarios in order to assess the risk for the environment.
authors.affiliation: Institute of Soil Science and Land Evaluation, Biogeophysics Section, Hohenheim University, Emil-Wolff-Str. 27, 70593 Stuttgart, Germany. Electronic address: bannwart@uni-hohenheim.de.
authors.forename: M A
authors.initials: MA
authors.lastname: Bannwarth
authors.affiliation: Institute of Soil Science and Land Evaluation, Biogeophysics Section, Hohenheim University, Emil-Wolff-Str. 27, 70593 Stuttgart, Germany.
authors.forename: W
authors.initials: W
authors.lastname: Sangchan
authors.affiliation: Institute of Soil Science and Land Evaluation, Biogeophysics Section, Hohenheim University, Emil-Wolff-Str. 27, 70593 Stuttgart, Germany.
authors.forename: C
authors.initials: C
authors.lastname: Hugenschmidt
authors.affiliation: Institute of Soil Science and Land Evaluation, Biogeophysics Section, Hohenheim University, Emil-Wolff-Str. 27, 70593 Stuttgart, Germany.
authors.forename: M
authors.initials: M
authors.lastname: Lamers
authors.affiliation: Institute of Soil Science and Land Evaluation, Biogeophysics Section, Hohenheim University, Emil-Wolff-Str. 27, 70593 Stuttgart, Germany.
authors.forename: J
authors.initials: J
authors.lastname: Ingwersen
authors.affiliation: Department of Geography, National University of Singapore, 10 Kent Ridge Crescent, 119260, Singapore.
authors.forename: A D
authors.initials: AD
authors.lastname: Ziegler
authors.affiliation: Institute of Soil Science and Land Evaluation, Biogeophysics Section, Hohenheim University, Emil-Wolff-Str. 27, 70593 Stuttgart, Germany.
authors.forename: T
authors.initials: T
authors.lastname: Streck
mesh_terms: D003198:Computer Simulation; D008956:Models, Chemical; D010575:Pesticides / Q000737:chemistry*; D013785:Thailand; D014872:Water Movements; D014874:Water Pollutants, Chemical / Q000032:analysis
chemical_list: D010575:Pesticides; D014874:Water Pollutants, Chemical
keywords: ANSELM; Atrazine; Chlorothalonil; Endosulfan; Pesticide simulation; SWAT; Tropical catchment