Comparative effects of logging and wildfire on carbon and fire dynamics in resprouting and non-resprouting eucalypt forests

The tall (\u3e30 m) eucalypt forests of south-eastern Australia are valued for their carbon storage and sequestration. However, they may also act as a carbon source given that they are prone to large wildfires and subject to commercial logging. Logging may reduce carbon stocks, but the relative losses compared to wildfire have not been quantified in many types of these forests. There is also growing evidence that logging may make carbon stocks in affected forests less resistant to fire and increase the risk of wildfire. These dynamics may also vary between eucalypt forest types. Carbon and fire dynamics in forests dominated by eucalypt species that cannot resprout new foliage after fire may be more sensitive to antecedent disturbance than the more widespread resprouting eucalypt forests. Non-resprouting eucalypt forests are often subject to stand replacing wildfires, but such a response is inherently absent in resprouting eucalypt forests. Non-resprouting eucalypt forests are also subject to clearfell logging, while logging practices in resprouting eucalypt forests are often less intense. Hence, a thorough comparative assessment of the effects of logging, wildfire and carbon dynamics across these broad forest types is needed to inform ongoing management of tall eucalypt forests. In this thesis, I compare how logging and wildfire affect forest carbon stocks, carbon stability (the capacity for carbon stocks to persist through, and recover after likely disturbances) and the risk of fire. The effects of logging and wildfire are compared between resprouting and non-resprouting eucalypt forests. I measured above ground carbon stocks and fuel characteristics (using a terrestrial laser scanner) along approximately 80-year chronosequences of logging and wildfire. Most sites in the resprouting forest study area were subsequently burnt by a mixed severity fire during the 2019-2020 fire season, enabling me to measure the change in carbon stock associated with wildfire and how it was affected by antecedent disturbance and fire severity. I also assessed the effects of variations in fuel characteristics on the severity of the 2019-2020 wildfires. To determine the effects of logging and wildfire on fire weather conditions, I measured fire weather conditions below the canopy across approximately 70-year chronosequences of logging and wildfire in the resprouting study area

Uncertainty in the modeling of spatial big data on a pattern of bushfires holes

This paper focuses on the presence of vegetation patches, called holes remaining after forest fires. Holes are of interest to explore because their vegetation is affected by severe temperature stress nearby, although they can serve as an agent to regenerate a forest after the burn. Further, it is interesting to know why holes emerge at all, while little if anything is known about their structure and distribution in space. A statistical analysis of their presence and abundance and a spatial statistical analysis to analyze their positions was done within four forest fire footprints. Fractal dimension of the holes was compared to that of the forest fire footprint, whereas remote sensing imagery was used to identify the normalized difference vegetation index (NDVI) of the patches before and after the fire. Results showed that the fractal dimension of the holes is lower than that of the forest fire footprint, and that the NDVI is slowly recovering to the original NDVI. Differences with the NDVI of the surrounding areas remain large. We concluded that patches of vegetation after a forest fire are interesting to study, providing clues of why unburned patches occur despite the fire presence nearby, how they can be characterized spatially and how the vegetation composition responds to such nearby fire. The Recommendations for Resource Managers: Forest fires affect the forests, and have an effect on the population living within the forest and close to it. A forest fire commonly leaves behind a large number of unburnt vegetation patches. In this study we call them holes. These holes have been under severe heat and smoke pressure, but have similar tree species and forest structure as the original forest. They serve as the starting point to regenerate the forest. The primary implications for resource management are as follows: A better understanding of where they are, and how they are composed may help to understand the behavior of a fire. Their characterization may help to better understand the relation between vegetation as a fuel for forest fire. Their biodiversity will improve the fire spread modeling of burns that are carried out for management of a forest stand

Remote Sensing of Savannas and Woodlands

Savannas and woodlands are one of the most challenging targets for remote sensing. This book provides a current snapshot of the geographical focus and application of the latest sensors and sensor combinations in savannas and woodlands. It includes feature articles on terrestrial laser scanning and on the application of remote sensing to characterization of vegetation dynamics in the Mato Grosso, Cerrado and Caatinga of Brazil. It also contains studies focussed on savannas in Europe, North America, Africa and Australia. It should be important reading for environmental practitioners and scientists globally who are concerned with the sustainability of the global savanna and woodland biome

Remote Sensing in Mangroves

The book highlights recent advancements in the mapping and monitoring of mangrove forests using earth observation satellite data. New and historical satellite data and aerial photographs have been used to map the extent, change and bio-physical parameters, such as phenology and biomass. Research was conducted in different parts of the world. Knowledge and understanding gained from this book can be used for the sustainable management of mangrove forests of the worl