Marxan with Zones: Software for optimal conservation based land- and sea-use zoning

Marxan is the most widely used conservation planning software in the world and is designed for solving
complex conservation planning problems in landscapes and seascapes. In this paper we describe
a substantial extension of Marxan called Marxan with Zones, a decision support tool that provides landuse
zoning options in geographical regions for biodiversity conservation. We describe new functions
designed to enhance the original Marxan software and expand on its utility as a decision support tool.
The major new element in the decision problem is allowing any parcel of land or sea to be allocated to
a specific zone, not just reserved or unreserved. Each zone then has the option of its own actions,
objectives and constraints, with the flexibility to define the contribution of each zone to achieve targets
for pre-specified features (e.g. species or habitats). The objective is to minimize the total cost of
implementing the zoning plan while ensuring a variety of conservation and land-use objectives are
achieved. We outline the capabilities, limitations and additional data requirements of this new software
and perform a comparison with the original version of Marxan. We feature a number of case studies to
demonstrate the functionality of the software and highlight its flexibility to address a range of complex
spatial planning problems. These studies demonstrate the design of multiple-use marine parks in both
Western Australia and California, and the zoning of forest use in East Kalimantan.