Sustainable Livestock Production

It is often said anecdotally that farmers and graziers are the original conservationists. The supporting argument is: what grower in their right mind would damage their resource base and their principal means of future wealth? While the logic is impeccable, the global history of desertification and collapse of civilisations due to environmental failure (Dregne, 1983; Diamond, 2005) means that agricultural sustainability is far from assured, raising questions about the ability of primary producers to conserve soil and water resources despite the best intentions. While there are many agricultural systems that have persisted for centuries or millennia, most of these underpin steady-state economies not subject to overpowering external pressures (Diamond, 2005). In contrast, modern agriculture both in developing and developed countries is beset with rapid changes in the decision-making environment and massive external social, economic and ecological pressures. While western agriculture has been remarkably successful in feeding a rapidly growing global population in the past 40 years, there have been opportunity costs and problems along the way (Tilman et al., 2002). Worldwide, 24% of global land area declined in climate-adjusted net primary productivity (NPP) over the period 1981–2003, as assessed by remote sensing of the normalised difference vegetation index (Bai et al., 2008). Only 16% registered an improvement. Degrading areas were mainly in Africa south of the equator, south-east Asia and southern China, north-central Australia, the Pampas and swathes of boreal forest in Siberia and North America. Overall, the environmental performance of agriculture has improved in OECD countries since 1990, but with significant variations within countries and widespread increases in on-farm energy use and water use and declines in wild species and ecosystem diversity (OECD, 2008).