title: Gradual regime shifts in fairy circles.
abstract: Large responses of ecosystems to small changes in the conditions--regime shifts--are of great interest and importance. In spatially extended ecosystems, these shifts may be local or global. Using empirical data and mathematical modeling, we investigated the dynamics of the Namibian fairy circle ecosystem as a case study of regime shifts in a pattern-forming ecosystem. Our results provide new support, based on the dynamics of the ecosystem, for the view of fairy circles as a self-organization phenomenon driven by water-vegetation interactions. The study further suggests that fairy circle birth and death processes correspond to spatially confined transitions between alternative stable states. Cascades of such transitions, possible in various pattern-forming systems, result in gradual rather than abrupt regime shifts.
authors.affiliation: Department of Solar Energy and Environmental Physics, Blaustein Institutes for Desert Research, Ben-Gurion University of the Negev, Sede Boqer Campus 8499000, Israel.
authors.forename: Yuval R
authors.initials: YR
authors.lastname: Zelnik
authors.affiliation: Department of Solar Energy and Environmental Physics, Blaustein Institutes for Desert Research, Ben-Gurion University of the Negev, Sede Boqer Campus 8499000, Israel Department of Physics, Ben-Gurion University of the Negev, Beer Sheva 8410501, Israel.
authors.forename: Ehud
authors.initials: E
authors.lastname: Meron
authors.affiliation: Department of Solar Energy and Environmental Physics, Blaustein Institutes for Desert Research, Ben-Gurion University of the Negev, Sede Boqer Campus 8499000, Israel bel@bgu.ac.il.
authors.forename: Golan
authors.initials: G
authors.lastname: Bel
mesh_terms: D000465:Algorithms; D018533:Biomass; D002980:Climate; D057231:Climate Change; D017753:Ecosystem; D008962:Models, Theoretical; D010944:Plants / Q000145:classification / Q000378:metabolism*; D011157:Population Dynamics; D011891:Rain; D013997:Time Factors; D014867:Water / Q000378:metabolism
chemical_list: D014867:Water
keywords: fairy circles; hybrid states; pattern formation; regime shifts; vegetation self-organization