Wildfires as an ecosystem service
Wildfires are often viewed as destructive disturbances. In a recent paper we propose that when including both evolutionary and socioecological scales, most ecosystem fires can be understood as natural processes that provide a variety of benefits to humankind [1]. Wildfires provide open habitats that enable the evolution of a diversity of shade-intolerant plants and animals that are a source of products used by humans since long ago. Wildfires also regulate pests and catastrophic fires, contribute to the regulation of the water and carbon cycles, and could help plants in their adaptation to novel climates. That is, there are many provisioning, regulating, and cultural services that we obtain from wildfires (box below). Prescribed fires are a tool for mimicking the ancestral role of wildfires in a highly populated world.
Figure: Schematic representation of the factors occurring at the evolutionary (green square) and at the socioecological (yellow square) scale associated with fire regimes and ecosystem services. Natural (historical) wildfire regimes create open habitats that can promote specific adaptations, biodiversity, and overall functioning in fire-prone ecosystems; these are the supporting services necessary for the production of all other services (table below). Decisions and policies may modify fire regimes (anthropogenic fire regimes) modulating ecosystem functioning and services (socioecological feedback); that is, policy decisions may switch between maintaining ecosystem services (stabilizing feedback) or generating unsustainable fire regimes (disruption of the feedback). Decisions and policies (bottom right corner) include fire and landscape management decisions, but also include socioeconomic changes that have implications on fire regimes (eg rural abandonment [2]). From [1].
Examples of ecosystem services provided by recurrent wildfires to early and to contemporary societies. For more details, see [1]:
- Provisioning services:
– Provide open spaces for pastures, agriculture, and hunting
– Stimulate germination of desirable annual ‘crops’ postfire
– Provide carbohydrates from underground plant organs
– Provide craft and basketry material (resprouts)
– Maintaining open spaces for grazing and hunting
– Provide essences, medicines, flowers (ornamental) - Regulating services
– Pest control for humans and livestock
– Reduce catastrophic wildfires
– Accelerates species replacement in changing conditions
– Enhance flowering and pollinator activity
– Water regulation
– Carbon balance - Cultural services
– Spiritual, inspirational
– Ecotourism in open ecosystems
– Recreational hunting
– Scientific knowledge on the origin of biodiversity
– Knowledge on ancestral fire management techniques
Cover of the June 2019 issue of Frontiers in Ecology & Environment (17, 6) where our papers is featured. California poppy (Eschscholzia californica) flowering postfire enhances pollination.
Illustrating ecosystems services by fire is not easy; here are some examples of pictures I received to potentially illustrate this paper; most of them did not finally go to the paper. Thanks to the contributes! – [click the photo to enlarge]
References
[1] Pausas J.G. & Keeley J.E. 2019. Wildfires as an ecosystem service. Frontiers in Ecology and Environment 17: 289-295 [doi | pdf | summary for managers]
[2] Pausas J.G. & Fernández-Muñoz S. 2012. Fire regime changes in the Western Mediterranean Basin: from fuel-limited to drought-driven fire regime. Climatic Change 110: 215-226. [doi | springer | pdf]