SWAT Literature Database for Peer-Reviewed Journal Articles

Title:Assessment of nutrient entry pathways and dominating hydrological processes in lowland catchments. 
Authors:Schmalz, B., F. Tavares, and N. Fohrer 
Journal:Advances in Geosciences 
Article ID: 
URL (non-DOI journals):http://hal.archives-ouvertes.fr/hal-00297009/ 
Broad Application Category:hydrologic only 
Primary Application Category:hydrologic assessment 
Secondary Application Category:calibration, sensitivity, and/or uncertainty analysis 
Watershed Description:517 km^2 Treene and 50 km^2 Kielstau subwatershed 
Calibration Summary: 
Validation Summary: 
General Comments: 
Abstract:The achievement of a good water quality in all water bodies until 2015 is legally regulated since December 2000 for all European Union member states by the European Water Framework Directive (EU, 2000). The aim of this project is to detect nutrient entry pathways and to assess the dominating hydrological processes in complex mesoscale catchments. The investigated Treene catchment is located in Northern Germany as a part of a lowland area. Sandy, loamy and peat soils are characteristic for this area. Land use is dominated by agriculture and pasture. Drainage changed the natural water balance. In a nested approach we examined two catchment areas: a) Treene catchment 517 km^2, b) Kielstau catchment 50 km^2. The nested approach assists to improve the process understanding by using data of different scales. Therefore these catchments serve not only as an example but the results are transferable to other lowland catchment areas. In a first step the river basin scale model SWAT (Soil and Water Assessment Tool, Arnold et al., 1998) was used successfully to model the water balance. Furthermore the water quality was analysed to distinguish the impact of point and diffuse sources. The results show that the tributaries in the Kielstau catchment contribute high amounts of nutrients, mainly nitrate and ammonium. For the parameters nitrate, ammonium and phosphorus it was observed as a tendency that the annual loads were increasing along the river profile of the Kielstau.