The human dimension of fire regimes on Earth
Humans and their ancestors are unique in being a fire‐making species, but ‘natural’ (i.e. independent of humans) fires have an ancient, geological history on Earth. Natural fires have influenced biological evolution and global biogeochemical cycles, making fire integral to the functioning of some biomes. Globally, debate rages about the impact on ecosystems of prehistoric human‐set fires, with views ranging from catastrophic to negligible. Understanding of the diversity of human fire regimes on Earth in the past, present and future remains rudimentary. It remains uncertain how humans have caused a departure from ‘natural’ background levels that vary with climate change. Available evidence shows that modern humans can increase or decrease background levels of natural fire activity by clearing forests, promoting grazing, dispersing plants, altering ignition patterns and actively suppressing fires, thereby causing substantial ecosystem changes and loss of biodiversity. Some of these contemporary fire regimes cause substantial economic disruptions owing to the destruction of infrastructure, degradation of ecosystem services, loss of life, and smoke‐related health effects. These episodic disasters help frame negative public attitudes towards landscape fires, despite the need for burning to sustain some ecosystems. Greenhouse gas‐induced warming and changes in the hydrological cycle may increase the occurrence of large, severe fires, with potentially significant feedbacks to the Earth system. Improved understanding of human fire regimes demands: (1) better data on past and current human influences on fire regimes to enable global comparative analyses, (2) a greater understanding of different cultural traditions of landscape burning and their positive and negative social, economic and ecological effects, and (3) more realistic representations of anthropogenic fire in global vegetation and climate change models. We provide an historical framework to promote understanding of the development and diversification of fire regimes, covering the pre‐human period, human domestication of fire, and the subsequent transition from subsistence agriculture to industrial economies. All of these phases still occur on Earth, providing opportunities for comparative research.
Document Type: Research Article
Affiliations: 1: School of Plant Science, Private Bag 55, University of Tasmania, Hobart, Tas., Australia 2: NCEAS, 735 State Street, Suite 300, University of Santa Barbara, Santa Barbara, CA, USA 3: Instituto de Física, Universidade de São Paulo 1516, Rua do Matão, Travessa R, 187, São Paulo, SP, Brazil 4: Botany Department, University of Cape Town, Rondebosch, South Africa 5: Geographic Information Science Center of Excellence (GIScCE) South Dakota State University, Brookings, SD, USA 6: Environmental Studies Program and Department of Ecology, Evolution and Marine Biology, University of California, Santa Barbara, CA, USA 7: Ecology, Evolution & Environmental Biology, Columbia University, New York, NY, USA 8: Menzies Research Institute, University of Tasmania, Private Bag 23, Hobart, Tas., Australia 9: Department of Environmental Science, Policy and Management, University of California, Berkeley, CA, USA 10: School of Geography and Environmental Science, Monash University, Melbourne, Vic., Australia 11: Department of Biology, University of Florida, Gainesville, FL, USA 12: Environmental Science, Policy, and Management Department, University of California, Berkeley, CA, USA 13: School of Life Sciences, Arizona State University, Tempe, AZ, USA 14: Department of Anthropology, Southern Methodist University, Dallas, TX, USA 15: Department of Earth Sciences, Royal Holloway University of London, Egham, UK 16: Department of Biological Sciences, Faculty of Science, National University of Singapore, Singapore 17: Laboratory of Tree-Ring Research, The University of Arizona, Tucson, AZ, USA
Publication date: 2011-12-01