Wild, tamed, and domesticated: Three fire macroregimes for global pyrogeography in the Anthropocene

Abstract

Climate and natural vegetation dynamics are key drivers of global vegetation fire, but anthropogenic burning now prevails over vast areas of the planet. Fire regime classification and mapping may contribute towards improved understanding of relationships between those fire drivers. We used 15 years of daily active fire data from the MODIS fire product (MCD14ML, collection 6) to create global maps of six fire descriptors (incidence, size inequality, season length, interannual variability, intensity, and fire season modality). Using multiple correspondence analysis (MCA) and hierarchical agglomerative clustering, we identified three fire macroregimes: Wild, Tamed, and Domesticated, each of which splitting into prototypical and transitional regimes. Interpretation of the six fire regimes in terms of their main drivers relied on the global maps of anthromes and Köppen climate types. The analysis yielded a two-dimensional space where the principal dimension of variability is primarily defined by interannual variability in fire activity and fire season length, and the secondary axis is based mainly on fire incidence. The Wild fire macroregime occurs mostly in cold wildlands, where burning is sporadic and fire seasons are short. Tamed fires predominate in seasonally dry tropical rangelands and croplands with high fire incidence. Domesticated fires are characteristic of humid, warm temperate and tropical croplands and villages with low fire incidence. The Tamed and Domesticated fire macroregimes, representing managed burning, account for 86% of all active fires in our dataset and for 70% of the global burnable area. Fourteen percent of active fires were found in the cold wildlands, and in the rangelands and forests of steppe and desert climates of the Wild macroregime. These results highlight the extent of human control over global pyrogeography in the Anthropocene.

The Portuguese Large Wildfire Spread database (PT-FireSprd)

“…The large number of fire behaviour observations, both at the polygon level (L2) and at the burning-period level (L3), provide enough information for a wide variety of potential applications. Combined with detailed information on the drivers, namely weather and fuel, and effects, it can be used to (i) improve current knowledge on the drivers affecting the behaviour of large wildfires, (ii) calibrate existing or new models which ultimately should help to better predict fire behaviour and support efficient fire management strategies (Alexander and Cruz, 2013), (iii) support the construction of case studies by fire analysts and contribute to better training of fire personnel (Alexander and Thomas, 2003), (iv) contribute to improved operational fire suppression strategies, (v) better understand how fire behaviour is linked to its effects (Collins et al, 2019), (vi) improve fire danger rating (Wotton, 2009), and (vii) better characterize fire regimes (Pereira et al, 2022). In addition, the fire behaviour classes described in Fig.…”

Assessing changes in global fire regimes

“…Human alteration of land cover and climate is reshaping wildfire on Earth (Bowman et al, 2020; Davis, 2021; T. M. Ellis et al, 2022; Pereira et al, 2022). Most terrestrial ecosystems have coevolved with fire over millions of years and many require periodic disturbance to maintain ecosystem structure and function (Bond et al, 2005; Harris et al, 2016).…”

Fire-human-climate interactions in the Bolivian Amazon rainforest ecotone from the Last Glacial Maximum to late Holocene

“…While fire is an ancient influence on the Earth system human agency has become increasingly important (Bowman et al, 2020). Today, humans are the primary cause of fire ignitions globally (Bowman et al, 2020;Pereira et al, 2022), and in fire-prone ecosystems including the SDTF and cerrado savannahs of the ARF-Ecotone, fires are more frequent when humans are in the landscape (Power et al, 2016;Le Page et al, 2017;Maezumi et al, 2018b;Brando et al, 2019). Indeed, as the keystone species of fire (Pyne, 2021), humans are the only species able to directly and deliberately manipulate fires through a variety of management practices (Levis et al, 2018;Bowman et al, 2020).…”