1SPRS, Vol.34, Part 2W2, “Dynamic and Multi-Dimensional GIS”, Bangkok, May 23-25, 2001 
347 
analysis function is another important components of Coastal 
GIS. 
C) Dynamic: Coastal system and its subsystem are 
dynamically interacting over space and time. Coastal GIS should 
be structured in the way that the data and models of dynamic 
processes (if can be defined) should be accommodated and 
operational. The ability of model integration is a crucial criteria for 
coastal GIS. This is one of the main challenge tasks in 
development of coastal GIS, since coastal environment is fraught 
with uncertainties. 
Halophila australis 
Ml Mixed Z. Capricorni & H. australis 
Posidonia australis 
Zostera Capricorni 
Fig. 3. Seagrass mapping using airphoto. 
D) Uncertainties: It is well recognised that coastal processes 
are fraught with uncertainties uncertainties (Cowell and Thom, 
1994; Zeng, et at., 1997) and most of coastal decision is made 
under (Funtowicz and Ravets, 1995; Otter and Capobianco, 
2000), and precaution principle (Deville and Harding, 1997) 
should be adopted. Therefore, coastal GIS should be able to 
cope with uncertainty. 
GIS application in coastal zone can benefit from the methods of 
assessment of error propagation (Heuvelink, 1993, Lanter and 
Veregin, 1992) and techniques of handling uncertainties that are 
routinely used in the field of Artificial Intelligence (Al) (Zadeh, 
1976; Kauffmann, 1975; Zenmmerman; 1991, Kabosa, 1996, 
Openshaw and Openshaw, 1997). 
Functions versus applications 
From the above discussion, it can be ascertained that the 
relationship between the functionalities and application level of 
Coastal GIS should be investigated for each project. 
For each project, first, the level of application should be defined 
and then the appropriate GIS functions are selected. Based on 
the review of current GIS applications in coastal zone, a