Using sedaDNA to assess the impact of cultural ecological management
Anthropogenic transformation can lead to significant changes to a landscape (Garcés-Pastor et al., 2021), and sedaDNA may assist in assessing these effects through time to inform contemporary ecological management plans. Environmental conditions and drivers can be revealed through microbial (Pérez et al., 2022), fungal (Talas, Stivrins, Veski, Tedersoo, & Kisand, 2021) and plant (Edwards et al., 2021; Hudson et al., 2022) sedaDNA. This would be of great benefit in areas where Traditional Knowledges are drawing the attention of non-Indigenous stakeholders, such as the fire-based ecology in Australia. Ecological management practices that utilise fire are integrated in many cultures around the world, including Aboriginal Australians (Coughland & Petty, 2012). Also referred to as cultural burning, the fire-based ecological practices of Aboriginal peoples go as far back as the early Holocene (Matthew A Adeleye, Haberle, Connor, Stevenson, & Bowman, 2021) and have had clear ecological impacts on animal and plant populations (Matthew Adesanya Adeleye, Haberle, Ondei, & Bowman, 2022; Bowman, 1998). Associating ecological communities identified by sedaDNA in stratigraphic horizons with the concentration of charcoal in the sediment can elucidate the effects of fire on the local environment.
Landscapes subject to cultural burnings have greater habitat diversity than comparable regions (Bliege Bird, Bird, Codding, Parker, & Jones, 2008), and the cumulative effects of fire practice over generations lead to the maintenance of high biodiversity (Bliege Bird et al., 2008). The anthropological justifications for this ecological manipulation by cultural burning vary by social and geographic necessity (Gott, 2005; Hill, Griggs, & Bamanga Bubu Ngadimunku, 2000; Yibarbuk et al., 2001). The cultural entwining of fire practices cannot be disentangled from socio-cultural practices (Yibarbuk et al., 2001). The following represent examples of diversity in the practical applications of cultural burnings and are not an exhaustive or exclusive list for the different Indigenous peoples mentioned. Peoples of the Ngaanyatjarra language group in the Western Desert of Australia have associated a decline in desert mammals, specifically the mitika(Bettongia leseur or rat-kangaroo) with a cessation in cultural burning (Burrows & Christensen, 1990). In south east Australia, annual burnings kept scrublands open for seed germination and movement across Country and in the north maintained diversity of food sources from both plants and animals on Yolngu Country (Gott, 2005; Yibarbuk et al., 2001). The Kuku-Yulanji people of Tropical North East Australia manage the interface of tropical rainforest and open grass-and-bush lands, and each environment’s unique resources, through cultural burning (Hill et al., 2000). Some Australian seeds have an obligate fire response to germinate and the increase of vegetative diversity is beneficial to humans and other animals (Bell, Plummer, & Taylor, 1993; Gott, 2005). Identifying changes in sedaDNA communities associated with changes in charcoal concentration would allow identification of wildfires both natural and anthropogenic, where a plateau in species diversity associated with higher charcoal concentration could indicate the presence of cultural burnings. Further, and with relevance to contemporary ecology, cultural burning can control wildfire spread (Coughlan & Petty, 2012; Mariani et al., 2022). It is reported that Traditional Knowledges of fire practices have adapted in many cases to manage the landscape formed by European colonisation (Matthew Adesanya Adeleye, Connor, Haberle, Herbert, & Brown, 2021; Coughlan & Petty, 2012; Hill et al., 2000; Yibarbuk et al., 2001). Collectively, Traditional Knowledges that mediate cultural burning are clearly important in understanding Australian ecology now and in the past and connecting Traditional Knowledges with sedaDNA has the potential to inform ecological management practices.