MARXAN boundary file maker - an ArcView GIS extension

Description

This extension produces a boundary data file for use in the MARXAN conservation planning software. MARXAN is a program that identifies portfolios of planning units that meet specified biodiversity conservation targets. By incorporating these boundary data as cost values, MARXAN preferentially selects portfolios that contain larger patches of units.

For example, the figures below show two portfolios, with existing conservation areas shown in dark green and new areas identified by MARXAN in light green. Figure 2 shows a portfolio that incorporates the boundary cost data. This less fragmented portfolio is likely to be more ecologically viable and easier to manage than the portfolio shown in Figure 1, which does not incorporate the boundary cost data.

The extension produces a text file that list the length of boundary shared by each of the planning units of a selected shapefile. The extension also allows external edges to be excluded from the boundary file, which is useful when these edges represent a coastline or another natural feature that should be included in the final portfolio (see Notes).

Click here to download the extension from the ESRI website.

This MARXAN boundary file maker function will make up part of the CLUZ extension, a piece of software that is currently being developed as a user-friendly ArcView GIS interface for MARXAN. The development of CLUZ has been funded by the British Government through their Darwin Initiative for the Survival of Species.

For more information visit the CLUZ web page or contact Bob Smith if you would like to be informed when CLUZ is available for download.

Notes

1) The extension allows you to exclude the external edges (see figure 3) of the planning unit theme from the output file. This is useful when the outside edges of your planning units form a natural boundary, such as a coastline, that you do not want to be under-represented in your conservation portfolio.

 

Relevant links

• MARXAN - a reserve system selection tool
  
  
• CLUZ - an ArcView GIS interface for Marxan
  
  
• Conservation planning in the Maputaland centre of endemism