SOS value and services of Australia’s soils

2019 World Soil Day Campaign

Soils are one of our most valuable resources in Australia, supporting our food, fibre, and water supplies. Soil underpins our agricultural production, directly contributing approximately $63 billion AUD per year to Australia’s economy (Jackson et al. 2018). Soils are also an important resource for their ability to store and filter water. These abilities sustain vegetation and human uses such as irrigation and stock watering across Australia, while also absorbing contaminants and purifying our water resources. Soil water storage helps to mitigate flooding.

Soil contains and directly supports the overwhelming majority of our terrestrial biodiversity from microscopic organisms such as fungi and bacteria to macroscopic organisms such as earthworms and wombats. These soil organisms play critical roles in important ecosystem processes including organic matter decomposition, nutrient cycling, enhancing plant nutrient uptake, carbon and nitrogen fixation from the atmosphere, and improving soil structure and aeration (Colloff 2011). Many of these ecosystem functions are vital to the indefinite sustainable use of our soils.

Our soils are also a vital player in global climate change mitigation as Australia’s soil store large amounts of organic carbon, last determined as 3.5% of the total global stocks in the 0-30 cm layer (Viscarra Rossel et al. 2014). However, native vegetation clearance and poor soil management have and continue to result in the loss of soil organic carbon and in enhanced greenhouse gas emissions. Capturing and retaining carbon in soil (sequestration) helps mitigate against climate change also improves soil health and productivity. Soil carbon sequestration is an accredited method under Australia’s Emissions Reduction Fund (ERF), thus storing carbon in soil can also produce direct economic benefits in addition to the improvements to soil function.

When considering all the above soil functions and services, Australia’s soils provide an estimated value of $930 billion AUD per year. This number is based on analysis of McBratney et al. (2017) were they determined that soil provides an average value of $121,022 AUD per square kilometre per year. Hence the value of soils far exceeds the value of the land itself which, while by far the most valuable Australian environmental asset (90% of total), is valued at $5.8 billion AUD (ABS 2018).

Soils are threatened by a number of degradation issues that result in large direct costs, indirect costs, and in lost economic opportunity for Australia.

 


ABS. 2018. 4655.0 – Australian Environmental-Economic Accounts, 2018. Australian Bureau of Statistics.

Colloff, M. 2011. The role of soil biodiversity in providing ecosystem services. Report prepared for the Australian Government Department of Sustainability, Environment, Water, Population and Communities on behalf of the State of the Environment 2011 Committee. DSEWPaC, Canberra.

Jackson, T., K. Zammit, and S. Hatfield-Dodds. 2018. Snapshot of Australian Agriculture. Australian Bureau of Agricultural and Resource Economics and Sciences, Canberra.

McBratney, A., C. Morgan, and L. Jarrett. 2017. The value of soil’s contributions to ecosystem services. Page 227 in D. Field, C. Morgan, and A. McBratney, editors. Global Soil Security, Progress in Soil Science. Springer International Publishing Switzerland.

Viscarra Rossel, R., R. Webster, E. Bui, and J. Baldock. 2014. Baseline map of organic carbon in Australian soil to support national carbon accounting and monitoring under climate change. Global Change Biology 20:2953-2970.