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Abstract. We evaluate a range of blue intensity (BI) tree-ringparameters in eight conifer species (12 sites) from Tasmania and New Zealandfor their dendroclimatic potential, and as surrogate wood anatomicalproxies. Using a dataset of ca. 10–15 trees per site, we measured earlywoodmaximum blue intensity (EWB), latewood minimum blue intensity (LWB), and theassociated delta blue intensity (DB) parameter for dendrochronologicalanalysis. No resin extraction was performed, impacting low-frequency trends.Therefore, we focused only on the high-frequency signal by detrending alltree-ring and climate data using a 20-year cubic smoothing spline. All BIparameters express low relative variance and weak signal strength comparedto ring width. Correlation analysis and principal component regressionexperiments identified a weak and variable climate response for mostring-width chronologies. However, for most sites, the EWB data, despite weaksignal strength, expressed strong coherence with summer temperatures.Significant correlations for LWB were also noted, but the sign of therelationship for most species is opposite to that reported for all coniferspecies in the Northern Hemisphere. DB results were mixed but performedbetter for the Tasmanian sites when combined through principal componentregression methods than for New Zealand. Using the fullmulti-species/parameter network, excellent summer temperature calibrationwas identified for both Tasmania and New Zealand ranging from 52 % to78 % explained variance for split periods (1901–1950/1951–1995), withequally robust independent validation (coefficient of efficiency = 0.41 to0.77). Comparison of the Tasmanian BI reconstruction with a quantitativewood anatomical (QWA) reconstruction shows that these parameters recordessentially the same strong high-frequency summer temperature signal.Despite these excellent results, a substantial challenge exists with thecapture of potential secular-scale climate trends. Although DB, band-pass,and other signal processing methods may help with this issue, substantiallymore experimentation is needed in conjunction with comparative analysis withring density and QWA measurements. 

Abstract Fire is a powerful ecological and evolutionary force that regulates organismal traits, population sizes, species interactions, community composition, carbon and nutrient cycling and ecosystem function. It also presents a rapidly growing societal challenge, due to both increasingly destructive wildfires and fire exclusion in fire‐dependent ecosystems. As an ecological process, fire integrates complex feedbacks among biological, social and geophysical processes, requiring coordination across several fields and scales of study.Here, we describe the diversity of ways in which fire operates as a fundamental ecological and evolutionary process on Earth. We explore research priorities in six categories of fire ecology: (a) characteristics of fire regimes, (b) changing fire regimes, (c) fire effects on above‐ground ecology, (d) fire effects on below‐ground ecology, (e) fire behaviour and (f) fire ecology modelling.We identify three emergent themes: the need to study fire across temporal scales, to assess the mechanisms underlying a variety of ecological feedbacks involving fire and to improve representation of fire in a range of modelling contexts.Synthesis: As fire regimes and our relationships with fire continue to change, prioritizing these research areas will facilitate understanding of the ecological causes and consequences of future fires and rethinking fire management alternatives.