thumb|Marxan logo '''MARXAN''' is a family of software designed to aid systematic reserve design on conservation planning. With the use of stochastic optimisation routines (Simulated Annealing) Marxan generates spatial reserve systems that achieve particular biodiversity representation goals with reasonable optimality. Over the years, Marxan has grown from its standard two zone application to consider more complex challenges like incorporating connectivity, probabilities and multiple zones. Along the way, Marxan's user community has also built plug-ins and interfaces to assist with planning projects.
Computationally, Marxan provides solutions to a conservation version of the 0-1 knapsack problem, where the objects of interest are potential reserve sites with given biological attributes. The simulated annealing algorithm attempts to minimise the total cost of the reserve system, while achieving a set of conservation goals (typically that a certain percentage of each geographical/biological feature is represented by the reserve system).
== History == Marxan is a portmanteau acronym, fusing '''MAR'''ine, and SPE'''XAN''', itself an acronym for '''SP'''atially '''EX'''plicit '''AN'''nealing. It was a product of Ian R. Ball's PhD thesis, while he was a student at the University of Adelaide in 2000, and was supervised and funded by Professor Hugh Possingham, the state of Queensland's (Australia) current Chief Scientist who holds a Federation Fellowship at the University of Queensland. It was an extension of the existing SPEXAN program.
In 2018, the vision of "Democratizing Marxan" began. Through the [https://biopama.org/ Biodiversity and Protected Areas Management programme (BIOPAMA)], funded by the European Union, the Joint Research Centre worked closely with The Nature Conservancy to prototype a web-based Marxan platform that improves accessibility to non-experts and supports our common vision of providing accessible tools for evidence-based conservation planning. This led to a partnership with Microsoft in 2020, which aims to scale Marxan's infrastructure for global accessibility and empowering users with the tools and data they need to make smarter decisions for the planet. In late 2020 and early 2021 Microsoft's Azure Quantum team made [https://cloudblogs.microsoft.com/quantum/2021/03/09/modernizing-conservation-planning-software-for-broader-global-impact/#:~:text=Using%20techniques%20inspired%20by%20quantum%20methods%2C%20the%20Azure,the%20conservation%20planning%20space%3A%20The%20Marxan%20planning%20engine. several open source contributions to Marxan] resulting in increased performance when running on multi-core machines and cloud environments. The resulting [https://github.com/Marxan-source-code/marxan version 4 of Marxan] is now available from [https://marxansolutions.org/ marxansolutions.org].
== Applications == thumb|Example Marxan outputs - selection frequency (the summed solution of each planning unit across all runs in a Marxan analysis). Figure 7 from McGowan et al. 2013,<ref>{{cite journal | vauthors = McGowan J, Hines E, Elliott M, Howar J, Dransfield A, Nur N, Jahncke J | title = Using seabird habitat modeling to inform marine spatial planning in central California's National Marine Sanctuaries | journal = PLOS ONE | volume = 8 | issue = 8 | article-number = e71406 | date = 2013-08-13 | pmid = 23967206 | pmc = 3742767 | doi = 10.1371/journal.pone.0071406 | bibcode = 2013PLoSO...871406M | doi-access = free }}</ref> a comparison of Marxan results prioritizing conservation of seabird habitat alone (scenario 1) and with the inclusion of human activities (scenario 2), shown by the cell selection frequency for 10, 30, and 50% conservation targets. MARXAN is the most widely used systematic reserve planning software in the world,<ref>Ball, I. R., Possingham, H. P., & Watts, M. E. (2009). Marxan and relatives: Software for spatial conservation prioritization. In A. Moilanen, K. A. Wilson, & H. P. Possingham (Eds.), Spatial conservation prioritisation: Quantitative methods and computational tools (pp. 185–210). Oxford University Press.</ref> and has been used to create the marine reserve network on the Great Barrier Reef, in Queensland, Australia, the largest marine protected area in the world.<ref>{{cite web | publisher = Environment News Service | work = International Daily Newswire | date = 2004 | title = Fish Boats Barred From One-Third of Great Barrier Reef | url = http://www.ens-newswire.com/ens/jul2004/2004-07-01-06.asp | access-date = 28 May 2006 }}</ref> It has been used for many other marine and terrestrial reserve planning applications.<ref>{{cite web | url = http://www.ecology.uq.edu.au/index.html?page=29781 | title = Ecology Centre MARXAN Homepage }}</ref>
* Channel Islands of California<ref>Airame S. 2005. Channel Islands National Marine Sanctuary: advancing the science and policy of marine protected areas. In: A Scholz and D Wright (Eds). ''Place matters: geospatial tools for marine science, conservation, and management in the Pacific Northwest''. Corvallis, OR: Oregon State University Press.</ref> * Gulf of Mexico<ref>{{cite book | vauthors = Chatwin A, Huggins A, Kramer P, Wear S, Zenny N, Jeo R | chapter = The greater Caribbean marine ecoregional assessment. Chapter IV. 1. Part IV: conservation initiatives in the Caribbean. Caribbean marine biodiversity: the known and the unknown. | veditors = Miloslavich P, Klein E | title = Census of Marine Life Caribbean. | publisher = DEStech Publications Inc. | location = Lancaster | date = 2005 | pages = 293–8 | archive-url = https://web.archive.org/web/20060523043432/http://www.intecmar.usb.ve/CoMLCaribbean/Summaries/summary_TNC.htm | archive-date = 2006-05-23 | chapter-url = http://www.intecmar.usb.ve/CoMLCaribbean/Summaries/summary_TNC.htm }}</ref> * Galapagos Islands * South Australia<ref>{{cite web |title = Selection Frequencies of Cells in the Australian South-East Marine Region |url = http://www.marine.csiro.au/nddq/ndd_search.Browse_Citation?txtSession=184 |work = Neptune - the National Oceans Office Data Directory |archive-url=https://archive.today/20041222042932/http://www.marine.csiro.au/nddq/ndd_search.Browse_Citation?txtSession=184 |archive-date=22 December 2004 }}</ref> * British Columbia<ref>{{cite web | url = http://depts.washington.edu/mpanews/MPA57.htm | archive-url = https://web.archive.org/web/20160303181925/http://depts.washington.edu/mpanews/MPA57.htm | archive-date = 3 March 2016 | title = Using Computer Software To Design Marine Reserve Networks: Planners Discuss Their Use Of Marxan | work = MPA News }}</ref> * Connecticut/New York * Central Coast of California * Baltic Sea<ref>{{cite journal | author = Helsinki Commission. | title = Towards an ecologically coherent network of well-managed Marine Protected Areas–Implementation report on the status and ecological coherence of the HELCOM BSPA network. | journal = Baltic Sea Environment Proceedings B | date = 2010 | volume = 124A | page = 147 | url = http://www.helcom.fi/stc/files/Publications/Proceedings/bsep124A.pdf | archive-url = https://web.archive.org/web/20110717130731/http://www.helcom.fi/stc/files/Publications/Proceedings/bsep124A.pdf | archive-date=2011-07-17 }}</ref> Beyond protected area network design, MARXAN has been applied to hundreds of conservation planning challenges, from designing optimal poaching patrols for game reserves and identifying where to conserve essential ecosystem services, to helping with transboundary ocean planning and understanding where transnational collaborations might best be prioritized to achieve conservation goals. While it would be almost impossible to list all of MARXAN's applications, here are a few examples beyond protected area network design. For software specific examples, see the Software section.
* '''Restoration activities''' in the Atlantic Forest, Brazil,<ref>{{cite journal| vauthors = Crouzeilles R, Beyer HL, Mills M, Grelle CE, Possingham HP |date=2015|title=Incorporating habitat availability into systematic planning for restoration: a species-specific approach for Atlantic Forest mammals |journal=Diversity and Distributions|language=en|volume=21|issue=9|pages=1027–1037|doi=10.1111/ddi.12349|issn=1472-4642|doi-access=free}}</ref> in the Yucatán Peninsula in the Mexican Caribbean,<ref>{{cite journal | vauthors = Adame MF, Hermoso V, Perhans K, Lovelock CE, Herrera-Silveira JA | title = Selecting cost-effective areas for restoration of ecosystem services | language = es | journal = Conservation Biology | volume = 29 | issue = 2 | pages = 493–502 | date = April 2015 | pmid = 25199996 | doi = 10.1111/cobi.12391 | hdl = 10072/124929 | hdl-access = free }}</ref> in the Murray–Darling Basin in South Australia,<ref>{{cite journal| vauthors = Jellinek S |date=2017|title=Using prioritisation tools to strategically restore vegetation communities in fragmented agricultural landscapes |journal=Ecological Management & Restoration|language=en|volume=18|issue=1|pages=45–53|doi=10.1111/emr.12224|issn=1442-8903|hdl=11343/291727|hdl-access=free}}</ref> and southwestern Alberta, Canada<ref>{{cite journal | vauthors = Braid AC, Nielsen SE | title = Prioritizing Sites for Protection and Restoration for Grizzly Bears (Ursus arctos) in Southwestern Alberta, Canada | journal = PLOS ONE | volume = 10 | issue = 7 | article-number = e0132501 | date = 2015-07-13 | pmid = 26168055 | pmc = 4500459 | doi = 10.1371/journal.pone.0132501 | bibcode = 2015PLoSO..1032501B | doi-access = free }}</ref> * '''Provision of ecosystem services''' in Central Coast ecoregion of California, United States,<ref name="pmid17076586"/> Telemark in southern Norway,<ref>{{cite journal | vauthors = Schröter M, Remme RP | title = Spatial prioritisation for conserving ecosystem services: comparing hotspots with heuristic optimisation | journal = Landscape Ecology | volume = 31 | issue = 2 | pages = 431–450 | date = February 2016 | pmid = 26843784 | pmc = 4722056 | doi = 10.1007/s10980-015-0258-5 }}</ref> and Vermont, United States<ref>{{cite journal | vauthors = Watson KB, Galford GL, Sonter LJ, Koh I, Ricketts TH | title = Effects of human demand on conservation planning for biodiversity and ecosystem services | journal = Conservation Biology | volume = 33 | issue = 4 | pages = 942–952 | date = August 2019 | pmid = 30614054 | pmc = 6850574 | doi = 10.1111/cobi.13276 }}</ref> * '''Understanding trade-offs''' between competing objectives in the Andes of Bolivia,<ref>{{cite journal | vauthors = Fastré C, Possingham HP, Strubbe D, Matthysen E | title = Identifying trade-offs between biodiversity conservation and ecosystem services delivery for land-use decisions | journal = Scientific Reports | volume = 10 | issue = 1 | page = 7971 | date = May 2020 | pmid = 32409694 | pmc = 7224365 | doi = 10.1038/s41598-020-64668-z | bibcode = 2020NatSR..10.7971F }}</ref> and Central Kalimantan, Indonesia<ref name = "Law_2017">{{cite journal| vauthors = Law EA, Bryan BA, Meijaard E, Mallawaarachchi T, Struebig MJ, Watts ME, Wilson KA |date=2017|title=Mixed policies give more options in multifunctional tropical forest landscapes |journal=Journal of Applied Ecology|language=en|volume=54|issue=1|pages=51–60|doi=10.1111/1365-2664.12666|issn=1365-2664|doi-access=free|hdl=10536/DRO/DU:30102070|hdl-access=free}}</ref> *'''Identifying management priorities''' in the Danube River Basin, Europe,<ref>{{cite journal | vauthors = Domisch S, Kakouei K, Martínez-López J, Bagstad KJ, Magrach A, Balbi S, Villa F, Funk A, Hein T, Borgwardt F, Hermoso V, Jähnig SC, Langhans SD | display-authors = 6 | title = Social equity shapes zone-selection: Balancing aquatic biodiversity conservation and ecosystem services delivery in the transboundary Danube River Basin | journal = The Science of the Total Environment | volume = 656 | pages = 797–807 | date = March 2019 | pmid = 30530149 | doi = 10.1016/j.scitotenv.2018.11.348 | bibcode = 2019ScTEn.656..797D | doi-access = free | hdl = 10810/44159 | hdl-access = free }}</ref> and South Africa's grassland biome<ref>{{cite journal | vauthors = Egoh BN, Reyers B, Rouget M, Richardson DM | title = Identifying priority areas for ecosystem service management in South African grasslands | journal = Journal of Environmental Management | volume = 92 | issue = 6 | pages = 1642–50 | date = June 2011 | pmid = 21334134 | doi = 10.1016/j.jenvman.2011.01.019 | hdl = 2263/15971 | hdl-access = free }}</ref> *'''Law enforcement activities''' in the Greater Virunga Landscape, in central Africa,<ref>{{cite journal| vauthors = Plumptre AJ, Fuller RA, Rwetsiba A, Wanyama F, Kujirakwinja D, Driciru M, Nangendo G, Watson JE, Possingham HP | display-authors = 6 |date=2014|title=Efficiently targeting resources to deter illegal activities in protected areas |journal=Journal of Applied Ecology|language=en|volume=51|issue=3|pages=714–725|doi=10.1111/1365-2664.12227|issn=1365-2664|doi-access=free}}</ref> and the Patos Lagoon estuary along the Brazilian coast<ref>{{cite journal | vauthors = Duarte de Paula Costa M, Mills M, Richardson AJ, Fuller RA, Muelbert JH, Possingham HP | title = Efficiently enforcing artisanal fisheries to protect estuarine biodiversity | journal = Ecological Applications | volume = 28 | issue = 6 | pages = 1450–1458 | date = September 2018 | pmid = 29944185 | doi = 10.1002/eap.1744 | url = https://eprints.utas.edu.au/30081/1/131775%20-%20Efficiently%20enforcing%20artisanal%20fisheries%20to%20protect%20estuarine%20biodiversity.pdf }}</ref>
MARXAN has been used extensively by The Nature Conservancy, and is a major part of the systematic planning tools being used in the Global Marine Initiative. The World Wildlife Fund used MARXAN to define a Global set of Marine Protected Areas, the ''Roadmap to Recovery'', which they used to petition the UN about the creation of open ocean marine reserve networks.
The software has also been used in terrestrial applications, such as: * The North American Wildlands Project. * Selecting priority areas for Global Mammal Assemblages.<ref name="pmid16040704">{{cite journal | vauthors = Ceballos G, Ehrlich PR, Soberón J, Salazar I, Fay JP | title = Global mammal conservation: what must we manage? | journal = Science | volume = 309 | issue = 5734 | pages = 603–7 | date = July 2005 | pmid = 16040704 | doi = 10.1126/science.1114015 | bibcode = 2005Sci...309..603C | s2cid = 44377512 }}</ref> * Planning the conservation of ecosystem services.<ref name="pmid17076586">{{cite journal | vauthors = Chan KM, Shaw MR, Cameron DR, Underwood EC, Daily GC | title = Conservation planning for ecosystem services | journal = PLOS Biology | volume = 4 | issue = 11 | article-number = e379 | date = October 2006 | pmid = 17076586 | pmc = 1629036 | doi = 10.1371/journal.pbio.0040379 | doi-access = free }}</ref> * The Great Sand Hills of Saskatchewan Regional Environmental Study <ref>{{cite web | title = Great Sand Hills Environmental Study | url = http://www.environment.gov.sk.ca/Default.aspx?DN=8663b7a6-5eb3-4e0b-b59b-0a0c81fdbc9f | work = The Government of Saskatchewan |archive-url = https://web.archive.org/web/20080729080500/http://www.environment.gov.sk.ca/Default.aspx?DN=8663b7a6-5eb3-4e0b-b59b-0a0c81fdbc9f|archive-date = 2008-07-29}}</ref>
Guyana’s National Biodiversity Strategy and Action Plan (2012–2020) documents collaboration involving the Protected Areas Commission, Conservation International Guyana and the University of Kent to develop a methodology using Marxan to map ecosystems and biodiversity areas for protected-area planning.<ref>{{cite report |title=Guyana National Biodiversity Strategy and Action Plan, 2012–2020 |publisher=Government of Guyana |url=https://www.cbd.int/doc/world/gy/gy-nbsap-v3-en.pdf |page=34}}</ref>
== Software == === Marxan === Marxan is the most widely used decision-support software for conservation planning globally, and has been used to build marine and terrestrial conservation systems covering approximately 5% of the Earth's surface. Marxan supports the design of cost-efficient networks that meet conservation targets for biodiversity.
=== Marxan with Zones === Marxan with Zones has the same functionality as Marxan but extends on the range of problems the software can solve and allows for the incorporation of multiple costs and zones into a systematic planning framework. Applications could be zoning for marine protected areas with various protection levels or landscapes that balance agriculture, biodiversity protection, and sustainable forestry zones. Marxan with Zones assigns each planning unit in a study region to a particular zone in order to meet a number of ecological, social and economic objectives at a minimum total cost.<ref>{{cite journal | vauthors = Watts ME, Ball IR, Stewart RS, Klein CJ, Wilson K, Steinback C, Lourival R, Kircher L, Possingham HP | display-authors = 6 |date=2009-12-01|title=Marxan with Zones: Software for optimal conservation based land- and sea-use zoning |journal=Environmental Modelling & Software|language=en|volume=24|issue=12|pages=1513–1521|doi=10.1016/j.envsoft.2009.06.005|issn=1364-8152 }}</ref> Some example locations where it has been used to inform decisions includes Raja Ampat, Indonesia,<ref>{{cite journal | vauthors = Grantham HS, Agostini VN, Wilson J, Magubhai S, Hidayat N, Muljadi A, Muhajir RC, Mongdong M, Beck MW, Possingham HP | display-authors = 6 |date=2013-03-01|title=A comparison of zoning analyses to inform the planning of a marine protected area network in Raja Ampat, Indonesia |journal=Marine Policy|language=en|volume=38|pages=184–194|doi=10.1016/j.marpol.2012.05.035|issn=0308-597X }}</ref> Tun Mustapha Park in Sabah, Malaysia,<ref>{{cite journal| vauthors = Jumin R, Binson A, McGowan J, Magupin S, Beger M, Brown CJ, Possingham HP, Klein C |date=October 2018|title=From Marxan to management: ocean zoning with stakeholders for Tun Mustapha Park in Sabah, Malaysia |journal=Oryx|language=en|volume=52|issue=4|pages=775–786|doi=10.1017/S0030605316001514|issn=0030-6053|doi-access=free}}</ref> Central Kalimantan, Indonesia,<ref name = "Law_2017" /> and Indonesian Borneo.<ref>{{cite journal| vauthors = Venter O, Possingham HP, Hovani L, Dewi S, Griscom B, Paoli G, Wells P, Wilson KA |date=2013|title=Using systematic conservation planning to minimize REDD+ conflict with agriculture and logging in the tropics |journal=Conservation Letters|language=en|volume=6|issue=2|pages=116–124|doi=10.1111/j.1755-263X.2012.00287.x |doi-access=free}}</ref>
=== Marxan with Connectivity === Marxan with Connectivity is an extension of the Marxan software family that allows for more sophisticated connectivity considerations in spatial planning. For example, sites may be connected through processes such as larval dispersal, animal migrations, and genetic flows which are desirable objectives in conservation plans. Marxan with Connectivity has been applied in freshwater, marine, terrestrial and land-sea systems to conserve sites that may be spatially distanced but ecologically connected. Some examples include planning for threatened loggerhead sea turtles (Caretta caretta) in the Mediterranean,<ref>{{cite journal| vauthors = Mazor T, Beger M, McGowan J, Possingham HP, Kark S |date=2016|title=The value of migration information for conservation prioritization of sea turtles in the Mediterranean |journal=Global Ecology and Biogeography|language=en|volume=25|issue=5|pages=540–552|doi=10.1111/geb.12434|issn=1466-8238|url=http://eprints.whiterose.ac.uk/105068/1/Mazor%20et%20al.pdf}}</ref> and accounting for river connectivity in the Guadiana River basin in the southwestern Iberian Peninsula.<ref>{{cite journal| vauthors = Hermoso V, Linke S, Prenda J, Possingham HP |date=2011|title=Addressing longitudinal connectivity in the systematic conservation planning of fresh waters | journal=Freshwater Biology|language=en|volume=56|issue=1|pages=57–70|doi=10.1111/j.1365-2427.2009.02390.x|issn=1365-2427|hdl=10272/4384|hdl-access=free}}</ref> It has been recently operationalized through 'Marxan Connect' - a new open source, open access Graphical User Interface (GUI) tool designed to assist conservation planners with the appropriate use of data on ecological connectivity in protected area network planning.<ref>{{cite journal| vauthors = Daigle RM, Metaxas A, Balbar AC, McGowan J, Treml EA, Kuempel CD, Possingham HP, Beger M |date=2020|title=Operationalizing ecological connectivity in spatial conservation planning with Marxan Connect |journal=Methods in Ecology and Evolution|language=en|volume=11|issue=4|pages=570–579|doi=10.1111/2041-210X.13349|issn=2041-210X|doi-access=free|hdl=10536/DRO/DU:30135307|hdl-access=free}}</ref>
=== Marxan with Probability === Marxan with Probability (MarProb) is Marxan with an additional objective function term that incorporates the probability of a site being destroyed at some point in the future. This function helps plan for persistence in protected area networks (see Game et al. 2008<ref>{{cite journal | vauthors = Game ET, Watts ME, Wooldridge S, Possingham HP | title = Planning for persistence in marine reserves: a question of catastrophic importance | journal = Ecological Applications | volume = 18 | issue = 3 | pages = 670–80 | date = April 2008 | pmid = 18488626 | doi = 10.1890/07-1027.1 | url = https://espace.library.uq.edu.au/view/UQ:161584/UQ161584_OA.pdf }}</ref>). Some examples where it has been used includes planning for Iberian herptile conservation while accounting for uncertainty in their predicted distributions due to climate change,<ref>{{cite journal|date=2011-07-01|title=Conservation planning under climate change: Toward accounting for uncertainty in predicted species distributions to increase confidence in conservation investments in space and time |journal=Biological Conservation|language=en|volume=144|issue=7|pages=2020–2030|doi=10.1016/j.biocon.2011.04.024|issn=0006-3207| vauthors = Carvalho SB, Brito JC, Crespo EG, Watts ME, Possingham HP }}</ref> and accounting for the inherent uncertainty associated with coral reef habitat maps in conservation planning, in the Kubulau District fisheries management area, Fiji.<ref>{{cite journal|date=2013-06-01|title=Incorporating uncertainty associated with habitat data in marine reserve design |journal=Biological Conservation|language=en|volume=162|pages=41–51|doi=10.1016/j.biocon.2013.03.003|issn=0006-3207| vauthors = Tulloch VJ, Possingham HP, Jupiter SD, Roelfsema C, Tulloch AI, Klein CJ |url=https://espace.library.uq.edu.au/view/UQ:306560/UQ306560OA.pdf }}</ref>
=== Companion Tools ===
==== Zonae Cogito ==== Zonae Cogito is a freely available software package that help manage and visualise Marxan projects.<ref>{{cite journal | vauthors = Segan DB, Game ET, Watts ME, Stewart RR, Possingham HP |date=2011-12-01|title=An interoperable decision support tool for conservation planning |journal=Environmental Modelling & Software|language=en|volume=26|issue=12|pages=1434–1441|doi=10.1016/j.envsoft.2011.08.002|issn=1364-8152 |url=https://espace.library.uq.edu.au/view/UQ:265709/UQ265709_OA.pdf}}</ref> The interface streamlines and simplifies the development and evaluation of alternative planning scenarios, allows direct editing to input files, calibrates parameters, and helps users easily access important output files for evaluation.
==== CLUZ ==== CLUZ (Conservation Land-Use Zoning software) is a QGIS plug-in that allows users to design protected area networks and other conservation landscapes and seascapes.<ref>{{cite journal| vauthors = Smith R |date=2019-01-31|title=The CLUZ plugin for QGIS: designing conservation area systems and other ecological networks |journal=Research Ideas and Outcomes|language=en|volume=5|article-number=e33510|doi=10.3897/rio.5.e33510|issn=2367-7163|doi-access=free}}</ref> It can be used for on-screen planning and also acts as a link for the Marxan conservation planning software. It was developed by Bob Smith and funded by the UK Government's E3 Sharing Space for Nature project.<ref>{{cite web | url = https://cluz-systematic-conservation-planning.github.io/ | title = Conservation Land-Use Zoning software (CLUZ) | work = Conservation Land-Use Zoning software (CLUZ) }}</ref>
==== Marxan toolboxes ==== Helpful tools developed by Trevor Wiens from Apropos Information Systems are available for both ArcGIS and QGIS users.<ref>{{cite web | url = https://qgis.org/en/site/forusers/download.html | title = Open Source Desktop GIS | work = qgis.org }}</ref>
==== Prioritizr ==== Systematic Conservation Prioritization in R – The prioritizr R package<ref>{{cite web | url = https://github.com/prioritizr/prioritizr | title = prioritizr R package | work = GitHub | date = 11 May 2021 }}</ref> uses integer linear programming (ILP) techniques to provide a flexible interface for building and solving conservation planning problems. It supports a broad range of objectives, constraints, and penalties that can be used to custom-tailor conservation planning problems to the specific needs of a conservation planning exercise. Once built, conservation planning problems can be solved using a variety of commercial and open-source exact algorithm solvers. In contrast to the algorithms conventionally used to solve conservation problems, such as heuristics or simulated annealing, the exact algorithms used here are guaranteed to find optimal solutions. Furthermore, conservation problems can be constructed to optimize the spatial allocation of different management actions or zones, meaning that conservation practitioners can identify solutions that benefit multiple stakeholders. Finally, this package has the functionality to read input data formatted for the ''Marxan'' conservation planning program, and find much cheaper solutions in a much shorter period of time than ''Marxan''.
== References == {{reflist}}
== External links == * {{cite web | url = https://marxansolutions.org/ | title = MARXAN Homepage, information and download }} * {{cite web | url = http://pacmara.org/tikiwiki/tiki-index.php?page=Marxan+Resources+and+Training | title = Marxan resources and training materials, PacMARA Marxan course information }} * {{cite web | url = http://depts.washington.edu/mpanews/MPA57.htm | archive-url = https://web.archive.org/web/20160303181925/http://depts.washington.edu/mpanews/MPA57.htm | archive-date = 3 March 2016 | title = Using Computer Software To Design Marine Reserve Networks: Planners Discuss Their Use Of Marxan | work = MPA News }} * {{cite report | vauthors = Gordon SN, Johnson KN, Reynolds KM, Crist P, Brown N | title = Decision support systems for forest biodiversity evaluation of current systems and future needs. Final Report-Project A-10 | publisher = National Commission on Science and Sustainable Forestry. | url = http://ncseonline.org/NCSSF/DSS/Documents/search/detail.cfm?key=MARXAN | archive-url = https://web.archive.org/web/20070927215653/http://ncseonline.org/NCSSF/DSS/Documents/search/detail.cfm?key=MARXAN | archive-date = 2007-09-27 }} {{Conservation of species}}
Category:Environmental conservation Category:Decision support systems Category:Protected areas