Reimagining the relationship between Gondwanan forests and Aboriginal land management in Australia's "Wet Tropics"

Abstract

The "Wet Tropics" of Australia host a unique variety of plant lineages that trace their origins to the super-continent of Gondwanaland. While these "ancient" evolutionary records are rightly emphasized in current management of the region, multidisciplinary research and lobbying by Rainforest Aboriginal Peoples have also demonstrated the significance of the cultural heritage of the "Wet Tropics." Here, we evaluate the existing archeological, paleoenvironmental, and historical evidence to demonstrate the diverse ways in which these forests are globally significant, not only for their ecological heritage but also for their preservation of traces of millennia of anthropogenic activities, including active burning and food tree manipulation. We argue that detailed paleoecological, ethnobotanical, and archeological studies, working within the framework of growing national and world heritage initiatives and active application of traditional knowledge, offer the best opportunities for sustainable management of these unique environments in the face of increasingly catastrophic climate change and bushfires.

Keywords: Agricultural Science; Biological Sciences; Botany; Environmental Monitoring; Environmental Resource; Environmental Science; Ethnobotany; Nature Conservation; Plant Biology; Plant Ecology.

Graphical abstract

Figure 1

Map of the mentioned archeological and paleoenvironmental sites and their location in relation to the Wet Tropics Bioregion of Queensland, Australia Changes in general vegetation groups (Neldner et al., 2019) within, and in the vicinity of, the Wet Tropics Bioregion of Queensland, Australia (Wet Tropics Management Authority, 2013) are shown: (A) before the clearance of major forested areas in 1954 and (B) their remnant extents in 2017.

Figure 2

Map of Aboriginal walking tracks and major cultural landmarks in the vicinity of Koombooloomba and Urumbal Pockets Shown in terms of the area's location within the Wet Tropics Bioregion and redrawn from Queensland Tully, Sheet No74, Zone 7, 2093 Tully 1 Inch Series, Surveyed by 5 Aust Fd Svy Coy AIF, Detail from Air Photos Dec. 1943, Brisbane. (A) View of Balan Garrya (Tully Falls Gorge); (B) photograph of Aboriginal children on a maintained walking track in the Wet Tropics. Source: Courtesy John Oxley Library, Brisbane (late 1800-early 1900s); (C) aerial image of Gumbalumba (Koombooloomba) Pocket showing the clear impact of past Aboriginal fire management still visible within modern rainforest vegetation. Source: Creative Commons Attribution 4.0 license. State of Queensland. (D) View of Urumbal Pocket from Balan Jaban (Tully River).

Figure 3

Compilation of rainforest foods and environments known to have been used by Rainforest Aboriginal groups (A) Sundacarpus amara (Black pine). Source: Photograph by R. Cosgrove. (B) Beilschmiedia bancroftii (Yellow walnut). Source: Photograph by R. Cosgrove. (C) Casuarius casuarius (cassowary). Source: Photograph by R. van Raders. (D) Incised slate grinding stone gifted to Mjöberg by a European settler in the Ravenshoe district. Source: Courtesy Museum of Ethnography, Stockholm. (E). Yellow walnut processing using traditional technology. Source: Photograph by R. Cosgrove. (F) Remnant tropical rainforest in the North Johnstone River district. Source: Photograph by R. Cosgrove.

Figure 4

Evidence of pre-colonial anthropogenically influenced plant distributions in Australia (A) The areas of three recent genetic studies focusing on (a) black bean (Castanospermum australe) (Rossetto et al., 2017); (b) Livistona mariae (Kondo et al., 2012); and (c) boabab (Adansonia gregorii) (Rangan et al., 2015). (B) Detail of black bean known distribution based on herbarium records (diamonds), genetic samples (circles), and songline locations in northern New South Wales northern river catchments (adapted from Rossetto et al. (2017), Figure 2).

Figure 5

Schematic showing changing fire dynamics following the disruption of Aboriginal burning practices within the rainforests of the Wet Tropics (A) Pre-1900: Pre-European Indigenous land management in the Wet Tropics Bioregion using fire to maintain open pockets for camp-sites, clear pathways, rainforest/sclerophyll edges, and intact, biodiverse rainforest areas with managed floors (B). Early to mid-1900s: Thickening of rainforest under-growth and invasion of rainforest species into sclerophyll pockets and rainforest/sclerophyll frontiers after restriction of Rainforest Aboriginal People from full-time occupation of country (C). Post 1940s: Disruptions to fire and Aboriginal land management resulting in dense under-growth, which, with human-induced climate warming and aridity, is leading to growing numbers of unprecedented wildfires.