Spatial metrics in fire ecology: seeking consistency amidst complexity

Technological advances, including remote sensing, have led to a proliferation of metrics used in ecological studies to examine spatial patterns of fire regimes and their ecological effects. Researchers can use many different metrics to analyse spatial variation in both fire events and resulting fire regimes, including fire size, shape, intensity, frequency and seasonality. However, variation in metric selection, definition, and application can yield inconsistent findings and/or difficulty in the synthesis of findings from different studies. 

This review aims to (i) visualise trends in spatial terminology within the broader fire ecology literature, (ii) characterise the variability among metrics for describing spatial fire patterns, and (iii) evaluate the ecological relevance of metrics, identifying opportunities to enhance consistency. This review comprises three sections. First, we used topic modelling to determine topic trends in fire ecology over the last three decades (1991–2025). We found a shift from studies primarily focused on individual fire regime aspects to a more holistic approach incorporating multiple fire regime aspects, including spatial patterns. Second, we present findings from a qualitative review, revealing marked variation in metric selection within and among taxa, biomes, and the technique used to measure spatial metrics. We also identified ecological processes, such as dispersal capacity, that prompt researchers to use more specific metrics to analyse their study system more precisely, leading to less consistency among studies. Finally, we offer recommendations for enhancing metric consistency whilst maintaining the flexibility to adapt and develop those metrics most relevant and informative for a given objective. 

As technological advances allow for a more complete description of the spatial attributes of a fire regime, there is a potential trade-off between generality and precision, reducing comparability among studies. To ensure ecological relevance, it is crucial to consider the characteristics of data, landscape, and ecological contexts when selecting and applying metrics. Recent advances in landscape analysis techniques, such as through applying information theory, are leading to metrics that can be broadly applicable across study systems. Using the most generalised metrics possible, reporting standardised metrics of all fire regime components, aligning with landscape ecology where appropriate, and staying updated on emerging techniques will ensure the fire ecology field can move forward with a more coordinated approach.