1. General Model Information

Name: TOXic substances in Surface WAters

Acronym: TOXSWA


Main medium: aquatic
Main subject: (eco)toxicology, hydrology, agriculture, behaviour of substances in surface waters
Organization level: Ecosystem
Type of model: partial differential equations (finite differences,1D), partial differential equations (finite differences,2D)
Main application: simulation/optimisation tool, research,
Keywords: water quality, chemicals, pesticides, aquatic, behaviour of pesticides, surface waters

Contact:

W.H.J. Beltman
P.O. Box 47
6700 AA Wageningen
The Netherlands

Phone: +31 317 474363
Fax: +31 317 419000
email: beltman@alterra.wag-ur.nl
Homepage: http://www.alterra.wageningen-ur.nl

Author(s):

P.I. Adriaanse, W.H.J. Beltman

Abstract:

TOXSWA describes the fate of pesticides entering water bodies
(i) by drift or atmospheric deposition,
(ii) by surface runoff, or
(iii) by drainage or leaching through the soil.
Entries into the simulated system can be instantaneous or distributed over a certain period. The entries can emanate from a point or they can be distributed over a certain length of the water body.

The simulated water body system is two-dimensional and consists of two subsystems: a water layer containing suspended solids and macrophytes and a sediment layer whose properties (porosity, organic matter content and bulk density) vary with depth. The vertical cross section of the water subsystem has a trapezoidal shape (see Fig. 2).
In the water layer subsystem, the pesticide concentration is assumed to be constant in the wetted cross section, so it is only a function of the horizontal direction.
In the sediment subsystem, the pesticide concentra-tion is a function of both the horizontal and vertical directions.
Water and sediment exchange pesticide mass through the wetted perimeter of the water body.

II. Technical Information

II.1 Executables:

Operating System(s): operating system: Windows95 / Windows NT
www.alterra.nl/models.htm

II.2 Source-code:

Programming Language(s): Fortran77
www.alterra.nl/models.htm

II.3 Manuals:

TOXSWA 1.2
It can be ordered at Alterra

II.4 Data:

www.alterra.nl/models.htm

III. Mathematical Information


III.1 Mathematics

Adriaanse, P.I. 1996. Fate of pesticides in field ditches: The TOXSWA simulation model. DLO Winand Staring Centre, Report 90, Wageningen.
Adriaanse, P.I., 1997. Exposure assessment of pesticides in field ditches: the TOXSWA model Pestic. Sci. 49: 210-212.

III.2 Quantities


III.2.1 Input

III.2.2 Output


IV. References

Adriaanse, P.I. 1996. Fate of pesticides in field ditches: The TOXSWA simulation model. DLO Winand Staring Centre, Report 90, Wageningen.
Adriaanse, P.I., 1997. Exposure assessment of pesticides in field ditches: the TOXSWA model Pestic. Sci. 49: 210-212. Beltman,
Beltman, W.H.J., P.I. Adriaanse, 1999. User's manual TOXSWA 1.2: Simulation of pesticide fate in small surface waters. DLO Winand Staring Centre, Technical Document 54, Wage-ningen.
Beltman, W.H.J., and P.I. Adriaanse, 1999. Proposed standard scenarios for an aquatic fate model in the Dutch authorization procedure of pesticides. Method to define standard scenarios determining exposure concentrations simulated by the TOXSWA model. DLO Winand Staring Centre, Report 161, Wageningen.


V. Further information in the World-Wide-Web


VI. Additional remarks

TOXSWA has been developed to be used in registration of pesticides.
Last review of this document by: W.H.J. Beltman Wed Nov 8 11:50:55 2000
Status of the document: Contributed by W.H.J. Beltman
last modified by Tobias Gabele Wed Aug 21 21:44:51 CEST 2002

Go back to Register of Ecological Models (R E M)