Generalized and specific state-and-transition models to guide management and restoration of Caldenal forests

TitleGeneralized and specific state-and-transition models to guide management and restoration of Caldenal forests
Publication TypeJournal Article
Year of Publication2019
AuthorsH. Peinetti R, Bestelmeyer BT, Chirino C, Kin A., Buss MElisa Fran
JournalRangeland Ecology and Management
Start Page230
Date Published03/2019
ARIS Log Number354042
Keywordsconstraint to restoration, fire-mediated feedback, resilience, thicketization

Management impacts and natural events can produce ecosystem state changes that are difficult to reverse. In such cases, a detailed understanding of drivers, thresholds, and feedback mechanisms are needed to design restoration interventions. The Caldenal ecoregion in central Argentina has undergone widespread state change, and restoration is urgently needed, but as yet there has been no knowledge synthesis to support restoration actions. In this paper, we provide evidence-based guidelines for ecological restoration of the Caldenal forest derived from a general to local conceptual understanding of ecosystemdynamics.Wedevelop a Caldenal forest state transition model based on a generalized fire-mediated savanna-woodland transitionmodel. The generalizedmodel depicts global similarities in fire-grass feedback loops as a primary factor controlling savanna to woodland transition (thicketization) in semiarid savannas around the world. An open forest is considered to be the reference state of the Caldenal that developed under a historical regime of frequent low-intensity fire. The introduction of large livestock herds in the region disrupted the positive fire-grass feedback loop and increased dispersal and recruitment of Prosopis caldenia, creating conditions for thicketization of the forest. Controlled, low-intensity fire can be used to build the resilience of an open forest state. Restoring open forest states from woodland states requires
a large-scale selective thinning and pruning operation. Long-term restoration requires breaking the positive livestock-thicketization−high-intensity fire feedback and reestablishing the positive grass-lowintensity fire feedback to ensure the persistence of a restored open forest state.