Page 213 - Biosystems Engineering

GIS-Based W atershed Modeling Systems 191

Certain modeling steps that are becoming necessary for compre-
hensive application of watershed models include sensitivity analysis,
calibration and validation, uncertainty analysis, and BMP optimiza-
tion. Currently available GIS-based modeling systems include some
of these steps but are currently not very sophisticated and user
friendly. In the future, incorporating these modeling steps in a GIS-
based interface will be critical.
With the invention of Internet GIS, more and more GIS function-
alities are currently being deployed through a Web browser. In the
watershed modeling area as well, researchers have started to use Web
browsers for screening-level watershed modeling studies. In future,
it would be possible to deploy a comprehensive watershed model
through a Web browser.
Using GIS has greatly simplified the task of watershed modeling,
which has resulted in efficient use of models, even by nonmodelers.
In future, GIS will make watershed modeling even simpler. However,
this has resulted in misuse of models. With new developments in
GIS-based modeling systems, it would be even more critical to train
future modelers in such a way that they have a thorough grounding
in underlying physical, chemical, and biological processes. This
would result in not only efficient but also accurate and effective mod-
eling efforts.

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