Marxan Software Archive

Abstract

Marxan is software that delivers decision support for reserve system design. The basic idea behind a reserve design problem is that a conservation planner has a large number of potential sites (or planning units) from which to select new conservation areas. They may wish to devise a reserve system which is made up of a selection of these planning units which will solve a problem that includes several ecological, social and economic criteria and principles. Marxan is primarily intended to solve a particular class of reserve design problem known as the 'minimum set problem', where the goal is to achieve some minimum representation of biodiversity features for the smallest possible cost (McDonnell et al. 2002). The rationale is that cheaper or less socially disruptive reserve networks are more likely to be implemented. Furthermore, meeting a set of targets for all conservation features provides a solid platform for expanding a reserve system in the future; reserve systems biased to habitats of little commercial value are often hard to expand. In minimum set problems the elements of biodiversity that you wish to conserve are entered as constraints to solutions of the problem (Possingham et al 2000). Given reasonably comprehensive data on species, habitats and/or other relevant biodiversity features, Marxan aims to identify the reserve system (a combination of planning units) that will meet user-defined biodiversity targets for the minimum cost (Ball and Possingham 2000; Possingham et al 2000).