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What is the topic of your doctoral research? Why is it important to study the topic?

My research focuses on fire risk, particularly in Mediterranean forests. Wildfires pose a significant threat to these ecosystems, damaging vegetation and undermining forests' ability to recover. However, fire can also have beneficial effects, such as promoting biodiversity and recycling nutrients in forest ecosystems. 

This dissertation investigates how and why forest fires occur, recur, and transform Mediterranean ecosystems over time, with a specific focus on fire-prone areas in Eastern Spain. By analyzing spatial and temporal patterns of fire activity, vegetation dynamics, and land-use changes, we aim to understand the key drivers behind these changes and their ecological consequences. 

In light of recent extreme fire events, it is clear that preventive and adaptive strategies are urgently needed. In the long term, effective forest planning can help manage these dynamics and reduce fire risks. This thesis addresses these issues, providing insights into their dynamics and the potential strategies to boost forests resilience and adaptation capacity.

What are the key findings or observations of your doctoral research?

Our research highlights the complex interactions between human activity, forested landscapes, and other drivers in shaping forest fire risk in Mediterranean areas. Human actions affect the likelihood of fire ignition, and land-use changes can either increase or reduce fuel continuity, thereby influencing how fires spread and impact forests. Climate also plays a key role by making vegetation more flammable under certain conditions. We found distinct factors driving the occurrence of small, medium, and large fires. Small fires are more likely in areas with high human accessibility, while large fires are also influenced by fuel type, especially in younger pine forests with dense shrub layers. This suggests that fire prevention and forest management strategies should be tailored to the scale of fire risk and the specific environmental conditions. 

Additionally, certain forest types are more prone to reburning, and drought events appear to influence the timing of these repeated fires. In the medium term, frequent fires tend to reduce forest structural complexity, often leading to shrub-dominated landscapes. We also observed that tree species composition affects fire impact. While some species combinations show lower tree mortality after fire events, simply mixing species with different fire-related traits does not necessarily reduce damage.

How can the results of your doctoral research be utilised in practice?

The methods and insights from this dissertation can support forest managers and policymakers in enhancing forest resilience to wildfires. Our research provides a practical framework for estimating fire risk across Spanish forests and identifying which environmental and human-driven factors most influence fire occurrence and impact. This information can be incorporated into strategic forest planning to design targeted prevention measures and long-term adaptation strategies, ultimately helping to safeguard forests in a changing climate. 

For instance, understanding that small fires are more prevalent in areas with high human accessibility suggests that targeted public awareness campaigns and stricter regulations in these zones could mitigate ignition risks. Conversely, recognizing that large fires are more likely in young pine forests with dense shrub layers indicates a need for proactive fuel management to reduce fuel continuity and flammability.

Moreover, insights into post-fire vegetation dynamics and the factors contributing to forest reburning can inform restoration efforts. By identifying forest types with higher reburn probabilities and understanding the role of drought events in fire recurrence, land managers can prioritize areas for rehabilitation and implement practices that enhance forest resilience. 

The findings from the species composition analysis provide valuable insights for designing more fire-resilient forest landscapes. One of the key takeaways is that not all mixed-species stands are equally effective in reducing fire damage. While species diversity is often assumed to enhance resilience, our results show that simply combining species with different fire-related traits does not automatically lead to lower fire-induced mortality. In practice, this means forest managers must go beyond promoting diversity for its own sake. Instead, they should strategically select species combinations based on their specific fire survival traits (e.g., resprouting ability, bark thickness, etc.) and the ecological interactions between them. 

Overall, our research supports a shift from reactive fire suppression to proactive fire regime management, emphasizing the importance of integrating ecological knowledge into land-use planning and forest management strategies to mitigate the long-term impacts of wildfires.

What are the key research methods and materials used in your doctoral research?

In this research we employed a multidisciplinary approach, combining spatial analysis, statistical modeling, and ecological assessment to investigate fire dynamics in Mediterranean forests. Key data sources included the Spanish National Forest Inventory, digital cartography, fire occurrence records, and environmental variables such as elevation, slope, and aspect. To analyze the size-dependent variables influencing fire occurrence, we utilized weighted generalized linear models, categorizing fires into small (5–50 ha), medium (50–500 ha), and large (>500 ha) classes. This approach allowed for the identification of distinct factors associated with each fire size category, providing information into fire risk patterns across different landscapes. 

The research also examined post-fire vegetation dynamics and the likelihood of forest reburning by assessing the temporal and spatial patterns of fire recurrence. This involved analyzing the interplay between vegetation types, fire history, and site conditions to determine factors contributing to repeated fires and changes in forest structure. 

Additionally, the last study investigated the impact of species composition on fire-induced stand damage by comparing mortality rates in monospecific and mixed-species forests. This analysis considered the fire-related traits of various tree species and their combinations, providing insights into how species diversity influences forest vulnerability to wildfires. Collectively, these methods facilitated understanding the complex interactions driving fire regimes in Mediterranean ecosystems, offering practical guidance for developing adaptive forest planning strategies.

The doctoral dissertation of Marina Peris Llopis, MSc (Agr & For), entitled Fires in Mediterranean forests: patterns of occurrence, transitions and impact will be examined at the Faculty of Science, Forestry and Technology, Joensuu Campus. The opponent will be Professor Cristina Vega, University of Lleida, Spain, and the custos will be Professor Blas Mola, 91����. Language of the public defence is English.

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