SOS Climate Change
The combination of Australia’s climate, landscape, and soils mean that only about 10% of the continent is suitable for crops and improved pasture (Orton et al. 2018). In addition to the small amount of productive land, Australia is vulnerable to climate change, and in particular to changes in rainfall. Rainfall is projected to decline in southern Australia and change in other areas of Australia (DAFF 2014). Small decreases in rainfall can be exacerbated by increased evaporation rates and increasing aridity can also reduce soil structural stability and increase salt accumulation (DAFF 2014, Rengasamy 2016). As such, improving water use efficiency and increasing sustainable use of Australia’s soil are key requirements for climate change adaptation (DAFF 2014). Soil management itself also contributes to climate change as poor soil management potentially releases large greenhouse gas emissions whereas conservation soil management can prevent the release or sequester carbon (Campbell 2008).
Climate change will exacerbate existing pressures and impacts; these pressures include shorter growing seasons, increased heat stress, an increase in extreme events, and a decrease in water availability (Burdon et al. 2017, Metcalfe and Bui 2017). Exacerbating existing pressures is likely to lead to an increase in soil degradation from processes such as erosion (both wind and water), salinisation and sodification from irrigation waters, and organic matter breakdown. It is likely that some production systems will become economically unviable in some regions; climate change is likely to reduce the global production of key commodities, with Australian production of some commodities decreasing by up to 19% by 2050 (Campbell 2008, Burdon et al. 2017). Furthermore, Australia is projected to be one of the most adversely affected countries due to climate change and may suffer declines of up to 79% in export commodities by 2050 (Campbell 2008).
Climate change adaptation will be vital for the sustainable management of Australia’s soil resources as it increases the risk of carbon losses, erosion, and desertification, salinisation, and natural disasters such as severe droughts and floods (Campbell 2008, ITPS 2015). In addition, increasing energy costs will affect landholder management options (Campbell 2008). Finally, climate change effects are disproportionately felt by large landholders and low socio-economic groups, further affecting landholders capacities to address changing conditions (Metcalfe and Bui 2017).
Burdon, J., T. J. Higgins, J. Pratley, R. Leigh, B. Gibson, A. McNeill, R. Gleadow, S. Powles, B.
Gillanders, B. Woods, and S. Hatcher. 2017. Grow. Make. Prosper. The decadal plan for Australian Agricultural Sciences 2017-26. Australian Academy of Sciences.
Campbell, A. 2008. Managing Australia’s soils – a policy discussion paper. Prepared for the National Committee on Soil and Terrain (NCST) through the Natural Resource Management Ministerial Council (NRMMC).
DAFF. 2014. The National Soil Research, Development and Extension Strategy, securing Australia’s soil, for profitable industries and healthy landscapes. Canberra.
ITPS. 2015. Status of the world’s soil resources technical summary. FAO – Intergovernmental Technical Panel on Soils, Italy.
Metcalfe, D. J., and E. N. Bui. 2017. Australia state of the environment 2016: land. Australian Government Department of the Environment and Energy, Canberra.
Orton, T., T. Mallawaarachchi, M. Pringle, N. Menzies, R. Dalal, P. Kopittke, R. Searle, Z. Hochman, and Y. Dang. 2018. Quantifying the economic impact of soil constraints on Australian agriculture: A case‐study of wheat. Land Degradation and Development 29:3866-3875.
Rengasamy, P. 2016. Salt-affected soils in Australia. GRDC, Adelaide.
Soil Science Australia acknowledges the traditional owners of the land and pays its respects to their Elders, past, present and future.