You are in the archive - for more current information look at the index card (»German)
Presentation at 8th annual SETAC Europe Meeting in Bordeaux 1998
Ittersim - Modelling and visualisation of the fate of detergent chemicals in the stream Itter
Schulze C., Matthies M., Trapp S. & Schröder F.R.
Abstract
For the simulation of spatial concentration patterns of 'down-the-drain' chemicals mathematical models were coupled with a Geographic Information System (GIS). As an application the detergent chemicals LAS (Linear Alkylbenzenesulfonate) and Boron were simulated in the Itter, a small tributary to the Rhine, which has a length of approximately 20 km. This study is based on the results of two masters theses from 1996 and 1997 (a LAS monitoring study and a georeferenced environmental simulation model). Three municipal sewage treatment plants (STP), serving a total of 182,137 inhabitant equivalents, are discharged into the Itter. In order to estimate the release of the aforementioned chemicals into the Itter, two different model concepts have been implemented and evaluated. In the first concept, the concentration at the confluence of the Itter with the Rhine is calculated based on an area related release estimate. In the case of the Itter, this concept underestimates the population discharging into the Itter, but overestimates the release. Sensitivity analyses prove that the predicted concentrations are influenced mainly by the connectivity to the STPs and the elimination processes in them. In the second concept, concentrations in various stretches of the Itter are calculated based on the release via point sources (i.e. STPs). In this approach, two ways to model instream removal were used. Statistical analyses show that the half-life of LAS can be modelled as a linear function of the water quality parameters TOC and ammonium. The models have been calibrated with measured concentrations from the monitoring program in 1996 and were compared with measured concentrations from 1997. Some results of this study are used within the GREAT-ER
project.
The parts of the Ittersim poster
Study Area
Data and Data Sources
The Regional Models
Results of Regional Models
The Water Models
Results of Water Models
Some Conclusions
Visualisation
The whole poster can be downloaded as well. It has to be mentioned, however, that due to a nice background picture the JPEG-file has a size of 3.2 Megabyte.
archived: August 2001 - last modified by the author: October 16, 1998
E-Mail: Carsten.Schulze@usf.Uni-Osnabrueck.DE [ index card (»German) ] Turn off background
[ English ]