The role of decomposer communities in managing surface fuels: a neglected ecosystem service

Abstract

Surface fuel loads are a key driver of forest fires and the target of hazard reduction burns to reduce fire risk. However, the role of biota in decomposition, or feedbacks between fire and decomposer communities are rarely considered. We review the evidence that decomposer organisms play an important role in surface fuel regulation and how this role is affected by fire. First, we outline the contribution of decomposer organisms to the breakdown of surface fuels. Next, we consider the three distinct phases through which fire regulates decomposer communities and how this may affect decomposition and future fire regimes. Finally, we consider interactions between global change and decomposer–fire feedbacks and the implications for fire management. Evidence indicates that decomposer organisms are important in regulating surface fuels and we propose that the biological basis and dynamic nature of fuel load control require greater attention. This includes better understanding of functional redundancy among decomposer organisms, the impacts of global change on the biota that drive decomposition and the factors that limit decomposer persistence and recolonisation following fires. By filling these knowledge gaps, we will be better armed to conserve and manage these functionally critical taxa in fire-prone ecosystems in a changing world.

Rainforest litter invertebrates decimated by high severity burns during Australia's gigafires

“…Here, we focussed on the scale of loss of macroinvertebrates following a major fire event, revealing that the 2019/2020 “gigafires” caused the loss of almost 60 billion macroinvertebrates in the 816 km 2 of south‐eastern Australian rainforests alone. This loss may have long‐term impacts on the functioning of these forests, where litter macroinvertebrates play a critical role in decomposition and nutrient cycling (Buckingham et al, 2015; Gießelmann et al, 2010; Meyer III et al, 2011), and in mediating fire by reducing fuel loads (Brennan et al, 2009; Gibb et al, 2022). Further, rainforests may provide a refuge and a source of recolonizers for surrounding drier forests, so declines in rainforest invertebrates are likely to affect recovery of surrounding forests.…”

“…Invertebrates are remarkable in their diversity and functional importance (Del Toro et al, 2012; Garibaldi et al, 2013; Lavelle et al, 2006; Stork, 2018). Litter invertebrates play key roles in fire suppression through their action as detritivores, making their conservation of particular concern in the context of fire (Gibb et al, 2022). When forests burn, substantial changes in the litter layer affect its biota in both the short‐ and longer‐term (Buckingham et al, 2019; Gibb et al, 2022; Menz et al, 2016).…”

“…Litter invertebrates play key roles in fire suppression through their action as detritivores, making their conservation of particular concern in the context of fire (Gibb et al, 2022). When forests burn, substantial changes in the litter layer affect its biota in both the short‐ and longer‐term (Buckingham et al, 2019; Gibb et al, 2022; Menz et al, 2016). In high severity fires, leaf litter, ground plants, shrubs and canopy cover can be completely incinerated (Collins et al, 2021).…”

“…Radiation from fire kills many organisms (e.g., in the soil layer, Wikars & Schimmel, 2001), but many litter invertebrates may escape to unburnt refuges (e.g., in Xanthorrhoea, Brennan et al, 2011; under soil, Dell et al, 2017; or up trees, Sensenig et al, 2017). These survivors and individuals dispersing from surrounding refuges seed the post‐fire populations (Gibb et al, 2022). However, following fire, large changes in microclimates (Neary et al, 1999) and resource availability (e.g., leaf litter, Cruz et al, 2012; Springett, 1979) are likely to limit the persistence and recovery of many species.…”

Contribution of remote sensing to wildfire trend and dynamic analysis in two of Ghana’s ecological zones: Guinea-savanna and Forest-savanna mosaic

“…The dynamic nature of the landscape deserves particular attention. Therefore, spatial and temporal information on savanna res and controlled burning in savannas and vulnerable ecosystems is important for research and management within disciplines such as re ecology (Gibb et al 2022), atmospheric chemistry (Hao et al 1990; Menaut et al 1995), soil studies (Butler et al 2019), and forestry (Liu 2015;Tian et al 2017;Hopkins et al 2020). Fire hazard on the landscape varies over time, owing to, among other factors, post-re succession and subsequent fuel accumulation patterns in burned areas (Wysong et al 2022).…”