Information and fact sheets on livestock production and climate change issues

Summary

Increasing soil carbon (C) levels in Australia's extensive grazing lands1 offers both a challenge and an opportunity to graziers and policy makers. While much of the recent interest in soil C is due to its climate change mitigation potential and possible future income from carbon credits, there are multiple co-benefits from improved soil health and ecosystem function.
With projections of a shift to a hotter and drier climate over much of Australia, it is a policy and management imperative to maintain and, where possible, increase C levels for improved productivity, resilience and adaptive capacity as well as climate mitigation benefits, particularly in the drier regions that make up the vast majority of grazing lands (Figure 1).
Graziers who have changed their practices over the past few decades, often as a response to land degradation, are reporting higher soil C levels, improved land condition, productivity and profitability, and greater resilience through use of grazing practices2 that restore natural processes and build healthy soils. Wider adoption of these restorative grazing practices is slow despite the apparent benefits. Reasons include that these practices can appear counter-intuitive to conventional graziers, with improved ecological literacy likely to improve understanding and facilitate adoption of soil C enhancing grazing practices (King, 2009).
This paper provides a synthesis of knowledge of soil organic carbon3 in Australia's grazing lands with a view to improving ecological literacy and decision making. It describes the role of C in soil health, and the main biogeochemical processes and grazing practices that affect soil C. Although intensive systems which would require life cycle considerations of inputs are outside the scope of this paper, the main C cycling processes are still relevant. This paper also does not consider greenhouse accounting policy or carbon trading issues that, although potential drivers of change in grazing practices, do not directly affect the C cycle.