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Ecological disturbances triggered by earthquakes and volcanic eruptions are of fundamental importance in structuring the temperate forests of southwestern South America and New Zealand. We review studies of the ecological effects of these tectonic phenomena and how they have been central to progress in the modern development of forest ecology in both regions. Studies of tectonic influences on the dynamics of southern temperate rainforests of Chile and New Zealand published in the 1970s and early 1980s contributed prominently to the shift away from the equilibrium paradigms dominant globally in the 1960s and towards modern non-equilibrium frameworks of forest dynamics. Empirical studies of tectonic ecology in these temperate forests in combination with critical evaluations of earlier successional theory have significantly advanced understanding of the roles of coarse-scale disturbance in the dynamics of forests in southwestern South America and New Zealand. Recognition that cohort forest structures triggered by exogenous disturbances such as wind storms and tectonic events are the norm rather than all-aged structures has been of fundamental importance to understanding the dynamics of these forests. The non-equilibrium patch dynamics framework for interpreting forest structure and dynamics bolstered by tectonic ecology studies in southern South America and New Zealand was of key importance in refining older views of these forests as being out of equilibrium with contemporary climate, revising understanding of the effects of introduced browsing animals on forest structure, and guiding the development of appropriate forest management practices. [ABSTRACT FROM AUTHOR]

In the context of global warming and increasing impacts of invasive plants and animals, we examine how positive fire–vegetation feedbacks are increasing the vulnerability of pyrophobic temperate forests to conversion to pyrophytic non-forest vegetation in southern South America and New Zealand. We extensively review the relevant literature to reveal how these temperate southern hemisphere floras have generated similar positive fire–vegetation feedback mechanisms resulting in increased vulnerability to anthropogenically altered fire regimens. For the two regions, we address the following questions. 1. What are the major plant species, physiognomic types and functional types characteristic of pyrophytic versus pyrophobic vegetation types and how do their traits affect flammability, resistance to fire and recovery after fire? 2. What are the roles of herbivory and microclimate in enhancing fire–vegetation feedbacks? 3. Are there similarities in trends of cover type transitions in relation to altered fire regimens? 4. How are climate change, land-use trends and the effects of introduced plants and animals affecting the vulnerability of these ecosystems to fire-induced transitions to alternative stable states? Most temperate forests of New Zealand and southern South America evolved under conditions of low fire frequencies so few taxa became adapted to recurrent fire. Current dichotomous landscapes consisting of juxtaposed pyrophobic and pyrophytic vegetation types are the outcome of the expansion of fire-resilient and fire-promoting species associated with the arrival of humans. Despite considerable differences in human history and biogeographic history, the case studies presented here show remarkable parallels in life-history traits of the key pyrophobic taxa, fire–vegetation feedback mechanisms, overall ecosystem responses to anthropogenic alteration of fire regimens, and likely vulnerability to expected global change influences on future fire regimens. [ABSTRACT FROM AUTHOR]