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Another limitation is the accuracy of Hydrologic Response Units HRUs simulating field variations including conservation practices. SWAT is being altered to account
for landscape spatial positioning so that conservation practices such as riparian buffers and vegetative filter strips can be adequately simulated.
Data files can be difficult to manipulate and can contain several missing records. The model simulations can only be as accurate as the input data. SWAT
does not simulate detailed event-based flood.
2.4 SWAT Mapwindows® Plugg-in
SWAT MapWindows MWSWAT is a graphical user interface, written in FORTRAN language www.waterbase.org. The MVSWAT consists of three key
components: 1 a pre-processor to generate the sub-basin topographic parameters and model
input parameters; 2 a facility for editing input data and to execute the SWAT simulation;
3 a post-processor to view the graphical and tabular simulation results. MWSWAT1.5 contains databases for soils, crops, pesticides, fertilizers,
tillage operations and urban simulations. All the existing databases are specifically related to the United States, but the user can easily add information to the databases
according to requirements. The MWSWAT requires
1. Personal computer using a Pentium I processor or higher, which runs at 166 MHz or faster
2. 64 Mb RAM minimum, higher is better. 3. Microsoft Windows 95, 98, NT 4.0 or Win2000 operating system with most
recent kernel patch, SWAT also can run in Windows XP. 4. VGA graphics adapter and monitor.
5. 50 Mb free memories on the hard drive for minimal installation and up to 300 Mb for a full installation.
6. Mapwindows 4.6 open sources GIS software 7. Dialog Developer 3.1 or later GIS software
In addition to the 50 Mb memory of hard disk space for installing the interface, a minimum 2 Gygabite hard drive is needed for storing Arc View, the
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SWATArc View interface, and project generated maps and tables Neitsch et al., 2005.
MapWindow is an open source Programmable Geographic Information
System that supports manipulation, analysis, and viewing of geospatial data and
associated attribute data in several standard GIS data formats. MapWindow is a
mapping tool, a GIS modeling system and a GIS application programming interface API all in one convenient redistributable open source solution Usman et al, 2008
and Gatry et al, 2007.
The MapWindow application is a free, extensible geographic information
system GIS that can be used in many ways:
•
As an open-source alternative desktop GIS
•
To distribute data to others
•
To develop and distribute custom spatial data analysis tools
2.5 Calibration and Validation
