Patch Mosaic Burning for Biodiversity Conservation: a Critique of the Pyrodiversity Paradigm

TLDR

Fire management increasingly promotes patch mosaic burning (PMB) to generate spatial and temporal heterogeneity under the assumption that pyrodiversity drives biodiversity, yet this concept has received little critical scrutiny. The study aimed to evaluate the application of PMB in tropical and subtropical savannas of Australia and Africa. The authors examined these ecosystems to assess PMB implementation. They found that PMB lacks empirical support—ecological effects of fire patterns are unknown, desired mosaics are unspecified, and many fire regimes are not ecologically meaningful—leading to rhetoric without operational guidance and calling for a more critical evaluation of pyrodiversity levels needed for biodiversity.

Abstract

Abstract: Fire management is increasingly focusing on introducing heterogeneity in burning patterns under the assumption that “pyrodiversity begets biodiversity.” This concept has been formalized as patch mosaic burning (PMB), in which fire is manipulated to create a mosaic of patches representative of a range of fire histories to generate heterogeneity across space and time. Although PMB is an intuitively appealing concept, it has received little critical analysis. Thus we examined ecosystems where PMB has received the most attention and has been the most extensively implemented: tropical and subtropical savannas of Australia and Africa. We identified serious shortcomings of PMB: the ecological significance of different burning patterns remains unknown and details of desired fire mosaics remain unspecified. This has led to fire‐management plans based on pyrodiversity rhetoric that lacks substance in terms of operational guidelines and capacity for meaningful evaluation. We also suggest that not all fire patterns are ecologically meaningful: this seems particularly true for the highly fire‐prone savannas of Australia and South Africa. We argue that biodiversity‐needs‐pyrodiversity advocacy needs to be replaced with a more critical consideration of the levels of pyrodiversity needed for biodiversity and greater attention to operational guidelines for its implementation.