Catchment planning tool

Abstract

Catchment managers need to prioritize areas for conservation and restoration because they have limited resources and compete with other land uses (Margules and Pressey, 2000). The Catchment Planning Tool (CPT) arose from the growing need by natural resource managers to identify and prioritize areas for conservation and restoration activities at the catchment scale (Marsh et al., 2007). The problem faced by efforts to develop environmental software is how to create a program that addresses all the needs of different audiences. Generally, attempts are made to develop a stand-alone tool that has every conceivable functionality. However, a more pragmatic approach is to develop a generic program that can accommodate the various issues faced by different catchment managers. Our solution was to develop the CPT (Figure 1), a Geographic Information System (GIS) program that utilizes The Invisible Modelling Environment (TIME) code base (Rahman et al., 2003) to display and interrogate spatial data. A plug-in system was built into the design of the CPT to allow it to communicate with any models that provide some prerequisite identification details. In the CPT, a plug-in is a program that provides extra functionality to the CPT, or that can access the CPT's functionality via the CPT's plug-in application programming interface (API). The CPT was designed to be able to use a combination of plug-ins to assess in-stream biological and environmental attributes and to predict the effects of environmental and management changes on rivers at a catchment scale. This ability of the CPT to easily plug-in programs makes it easy to extend the functionality of the CPT, giving it the flexibility required to address the different challenges that face a wide range of catchment managers. The basic CPT configuration includes the core CPT application, that displays GIS data and hosts plug-ins, a plug-in manager to organize other plug-ins, and a GIS Toolbox plug-in. The GIS Toolbox plug-in provides a collection of GIS functionality that can be used for both terrestrial and riverine applications. Catchment delineation from digital elevation models (DEM) and the routing of river properties (e.g. taxa composition and stream constituents) through a river system are examples of the functionality that is specific for river studies. TIME code implemented based on Prosser et al. (2001) was used to provide the catchment delineation functionality. The delineation of catchments enables the creation of a river network composed of nodes and links. By knowing the from-node and the to-node of a link, properties of streams can be routed up and down the network. For specific environmental problems, further plug-ins can be added to the basic CPT configuration to extend its functionality. MARXAN is a software program that is used for optimizing reserve design (Ball and Possingham, 2000; Possingham et al., 2000). A MARXAN plug-in was developed for the CPT. This paper demonstrates some of the functionality available within the basic CPT configuration and uses the MARXAN plug-in as an example of how the basic CPT functionality can be extended. The example shows how resource managers could employ the CPT plug-in architecture to seamlessly combine various models (MARXAN in this instance) and GIS functionality under one computer program. Figure 1. The Catchment Planning Tool (CPT) is a GIS interface for displaying and analyzing spatial data. Its functionality can be extended by adding plug-ins that are organized under the Plugins menu. (Figure Presented)