Urban expansion

Our cities and towns are growing, and there is increasing demand for land to be used for built infrastructure to support population growth. As a result, the built environment is outcompeting other land uses, and leading to removal of land from agricultural production or clearing of natural areas (see Land use) (see the Urban chapter). These changes in settlement patterns have also changed our bushfire exposure, requiring a rethink about how to live with Australia’s sclerophyllous native vegetation, which is inherently flammable.

While the natural state of bush flammability varies between biomes (Murphy et al. 2013) and in its degree of coupling with biodiversity (Bowman et al. 2016), fire-adapted eucalypt forests, particularly in the southern regions of Australia, accumulate high fuel loads. With infrequent natural sources of ignition (e.g. lightning), fires in these forests are generally of high intensity, resulting in significant ecological impact followed by a pulse of recovery over an extended period (Gill 1981). Generations of Indigenous communities living with these systems over many thousands of years adopted a cultural fire management strategy that involved selective, but more frequent, ignition to reduce fuels, resulting in cool fires of lower intensity and generally lower ecological impact (Chester 2020).

Early European settlement in Australia involved self-sustaining settlements, so that towns were surrounded by cleared agricultural land that provided both food and a separation from the threat of bushfires. For these early settlements, there was little need for a sophisticated fire management strategy. In bush areas, natural fires and Indigenous burning continued, but agricultural buffers ensured the impacts on humans were relatively low (Pyne 1998, Pyne 2006). As competition for land has increased around Australia’s major cities, agricultural land has been displaced, leading to peri-urban bush blocks that are no longer buffered from bushfires (Pyne 1998). New and varied urban ignition sources (e.g. Kilvert 2019), coupled with high-risk peri-urban infrastructure, require significant suppression efforts to try to remove fire from the landscape (Chester 2020). With the onset of extreme events associated with climate change, this strategy leads to significant risk to ecological assets, as well as to infrastructure and human life (AAS 2021).

In a post-pandemic digital era, modern settlement patterns are likely to proliferate across rural and regional Australia as more people are less tied to working in large cities (Hu 2020). Managing a more distributed network of people with exacerbated fire weather across whole landscapes is likely to have significant negative consequences for vulnerable biodiversity and ecosystems, with flow-on impacts to natural capital and diminished resilience of local communities. Local communities will need to revisit the objectives of their fire management strategies to balance the potential human impacts with natural capital values they wish to maintain.

Increasing urbanisation is also impacting Indigenous cultural heritage values. While the impact on Indigenous heritage sites may be seen directly, the impacts on socialisation and connection to Country are both direct and indirect. Increasing urbanisation affects cultural connection and use of areas, as well as associated cultural stories and, particularly, socialisation. Areas used for cultural transmission to younger generations by parents or elders through the activity of ‘being on Country’ are decreasing.


As the built environment expands, so too does infrastructure for service networks to support and connect population centres. This infrastructure includes transport routes (roads, rail), energy, water storages, communications and data, wind and solar farms, and waste disposal. Australia’s road network could wrap around the world 22 times (Infrastructure Australia 2019), making it a significant land use (see the Urban chapter).

Infrastructure networks may remove land from production, fragment other land uses (e.g. agriculture, forestry) or degrade natural areas (e.g. incremental loss of remnant roadside vegetation and biodiversity in agricultural landscapes). The extent of these infrastructure networks is evident in the human footprint map for Australia (Figure 4), which forms part of the global mapping by Beyer et al. (2020). These networks can also facilitate the spread of invasive non-native species (see Invasive species management), and some structures such as above-ground electricity networks can present landscape risks (e.g. bushfires). Infrastructure networks have been described as ‘growth inducing’ (Johnson et al. 2020), meaning that they incrementally induce and intensify development around them; the longer-term implications of this need to be taken into account in decisions to build or expand infrastructure.