| Title: | Ecohydrological modelling of water discharge and nitrate loads in a mesoscale lowland catchment, Germany |
| Authors: | Lam, Q.D., B. Schmalz and N. Fohrer |
| Year: | 2009 |
| Journal: | Advances in Geosciences |
| Volume (Issue): | 21 |
| Pages: | 49-55 |
| Article ID: | |
| DOI: | 10.5194/adgeo-21-49-2009 |
| URL (non-DOI journals): | |
| Model: | SWAT |
| Broad Application Category: | hydrologic and pollutant |
| Primary Application Category: | hydrologic assessment |
| Secondary Application Category: | nitrogen cycling/loss and transport |
| Watershed Description: | 50 km^2 Kielstau River, located in the lowland area of the State of Schleswig-Holstein in northern Germany. |
| Calibration Summary: | |
| Validation Summary: | |
| General Comments: | |
| Abstract: | The aims of this study are to identify the capacities
of applying an ecohydrological model for simulating flow
and to assess the impact of point and non-point source pollution
on nitrate loads in a complex lowland catchment, which
has special hydrological characteristics in comparison with
those of other catchments. The study area Kielstau catchment
has a size of approximately 50 km^2 and is located in
the North German lowlands. The water quality is not only
influenced by the predominating agricultural land use in the
catchment as cropland and pasture, but also by six municipal
wastewater treatment plants.
Ecohydrological models like the SWAT model (Soil and
Water Assessment Tool) are useful tools for simulating nutrient
loads in river catchments. Diffuse entries from the agriculture
resulting from fertilizers as well as punctual entries
from the wastewater treatment plants are implemented in the
model set-up.
The results of this study show good agreement between
simulated and measured daily discharges with a Nash-
Sutcliffe efficiency and a correlation coefficient of 0.76 and
0.88 for the calibration period (November 1998 to October
2004); 0.75 and 0.92 for the validation period (November
2004 to December 2007). The model efficiency for daily nitrate
loads is 0.64 and 0.5 for the calibration period (June
2005 to May 2007) and the validation period (June 2007
to December 2007), respectively. The study revealed that
SWAT performed satisfactorily in simulating daily flow and
nitrate loads at the lowland catchment in Northern Germany. |
| Language: | English |
| Keywords: | |