Effects of fire disturbance on terrestrial salamanders in mixed-coniferous forests of the Klamath/Siskiyou region of the Pacific Northwest.

摘要

An effective examination of fire disturbance on floral and faunal components requires research that integrates knowledge from multiple disciplines to understand the pattern and process controls affecting organisms in a complex system. However, current fire effects research typically focuses on the pattern response of organisms or their habitats with little integration of the dynamic fire process that created the pattern. This dissertation integrates an analysis of the processes of fire disturbance with terrestrial salamander ecology in a fire-dependent forest ecosystem, Klamath Province, California, USA.; In Chapter 1, I begin with a comprehensive review of disturbance ecology, focusing primarily on fire in forested ecosystems. Next, I discuss the current state of knowledge regarding effects of fire from the scale-extent of ground-dwelling vertebrate habitats through forested landscapes. Finally, I conclude with a overview of my specific research objectives.; In Chapter 2, I examine multi-scale vegetative responses to fire disturbance. Specifically, I characterize micro- and macro-scale forest structure and physical site characteristics across various fire disturbances. Finally, I discuss the concept of a fire refugium and examine potential fire effects in current and future forest dynamics of these critical environments.; In Chapter 3, I characterize a fire exclusion legacy in a fire-dependent forest system. Specifically, I quantify fire exclusion legacy in stands perturbed by fire. Next, I estimate and characterize potential fuel structure and biomass associated with post-fire forest structure. To conclude, I explore the implications of a hypothetical legacy-mediated disturbance model on future fire severity and forest resilience.; In Chapter 4, I explore faunal responses to fire disturbance through the examination of processes directly and indirectly affecting terrestrial salamander populations. I use classification tree models to compare various population metrics at the micro- and macro-scale. I also examine associations between animal presence and multi-scale forest structure, physical site characteristics, and fire disturbances.; I conclude with a synthesis that examines the applicability of a salamander-based fire severity model (Chapter 5). Specifically, I examine the utility of predictive models to integrate fire processes and the effects of fire on terrestrial salamanders. Finally, I discuss the application of my results to future management and conservation of terrestrial salamanders.