The Role of Fire in California’s Landscapes Across Spatial and Temporal Scales

The role of fire in California’s landscapes has dramatically changed in recent centuries with the arrival of European cultures and later by the influence of rapid climate change. Novel challenges face land and fire management in the forms of invasive species, human encroachment, severe fuel loads, and fire regime shifts. Because fire is a critical land management tool and natural process in California ecosystems, reintroducing prescribed fire to our ecosystems is increasingly necessary, but also more challenging than ever. It is now of utmost importance that we investigate and seek to understand the modern role of fire in historic, modern, and future ecosystems at multiple scales. First, I investigate the micro-scale effects of fire in an invaded ecosystem to elucidate how novel plant community dynamics in the face of fire. Studying fire-use related plant species interactions at the 1-m scale informs how we can expect plant communities to shift due to fire in the face of invasive species. This technique is a useful tool for managers and scientists to experiment with variations in fire-use to find ideal fire regimes in novel communities, and to prepare for fire-effects on plant communities. Second, I investigate prescribed fire effects across an invaded site of a similar plant community knowledge using information gained from these micro-scale investigations. Here I implement the knowledge gained from the micro-scale study, while incorporating more diverse investigations of fire effects, including soil nutrient and seedbank dynamics. This exploration allows for a more holistic understanding of fire-ecosystem interactions in these novel communities. The use of these intensive monitoring techniques on prescribed fire empower adaptive management by informing scientists and land managers of prescribed fire effects, and allowing for informed adjustments to practices based on results. Finally, I study the role of fire at a much larger scale through an investigation of seasonal conifer xylogenesis. By better understanding annual cambial development of California’s common mixed conifers, we can more accurately interpret fire scars and, in turn, California’s fire history. We can then also use this information to look to the future and inform decisions regarding management of our landscapes and firescapes in the face of rapid climate change