By Andrew Campbell
Food, water and energy security are finally being recognised as the most important national and international security issues, but an important element has been missing from the discussion — the soil.
That was the case until the [Australian] Prime Minister’s announcement at the ABARE Outlook conference [recently] that Agriculture Minister Tony Burke would look into ways to incorporate soil carbon in emissions trading.
Kevin Rudd’s announcement was welcome recognition that Australia will be unable to maintain its food exports, achieve water security or meet its greenhouse targets without a major improvement in soil management.
As a rule of thumb every calorie consumed requires a litre of water to produce.
With increasing population and changing consumption patterns (like increasing meat consumption in China), the world will need to produce twice as much food by 2050 as it does now, from about the same amount of land and water, or possibly less. In the past, we have kept up with increasing food needs mainly by clearing and irrigating more land, converting more natural forests to agriculture, diverting more water resources, using improved varieties and applying more fertilisers.
Those options are narrowing.
The International Water Management Institute recently completed a comprehensive assessment of the world’s water resources. It found that most of the world’s great food production basins (like our own Murray-Darling Basin) are effectively ‘closed’, with existing water resources already fully utilised or overallocated. Moreover, many countries are now reallocating land and water resources from food production to energy production by growing biofuel crops. India for example, aims to meet 10 per cent of its total gasoline needs from biofuels by 2030, which is projected to cause absolute water scarcity for food production.
Clearing more land for agriculture is highly undesirable from a greenhouse perspective and there are moves in many countries to re-establish forest cover on cleared agricultural lands.
Climate change impacts in many countries are projected to reduce water availability and increase the proportion of poor seasons, thus reducing agricultural productivity. As a major food exporter, this should be good news for Australia, creating major economic opportunities. However our capacity to capture these opportunities will depend to a large degree on how well we manage our own climate change impacts, and particularly our soils.
No-one could accuse the Australian Bureau of Agricultural and Resource Economics (ABARE) of being on the climate change bandwagon. Its Australian Commodities for the December 2007 quarter analysed the potential medium-long term impacts of climate change on agricultural productivity, exports and trade in Australia and internationally. It concluded that Australia will be one of the countries most adversely affected from climate change in terms of reductions in agricultural production and exports. ABARE estimated that Australian production of wheat, beef, dairy and sugar could decline by an estimated 9–10 per cent by 2030 and 13–19 per cent by 2050, compared with average global production declines in these commodities of 2–6 per cent by 2030 and 5–11 per cent by 2050.
Farmers have traditionally increased productivity by increasing fertiliser applications, but again climate change impacts and the policy responses to them change the equation. Agriculture is a major source of greenhouse gases (the second biggest emitter in Australia after power stations) and the use of nitrogenous fertilisers is the second biggest source of agricultural emissions behind enteric fermentation (the belching and farting of livestock). Declining reserves of rock phosphate and the energy costs embodied in fertiliser production are leading to rising prices for fertilisers, which are likely to increase further if there is a price on carbon.
So there will be an increasing squeeze on food production from climate change, reduced water availability, and increasing energy and fertiliser prices. We are already seeing rising food prices, with the index of food commodity prices at record levels.
How to beat the squeeze?
The other traditional ‘green revolution’ response to increase food production has been through genetic gain — the use of improved varieties. They will continue to have a major role to play, both through traditional plant breeding and through the application of molecular genetic technologies to produce genetically modified organisms (GMOs).
However the focus here is not GMOs, but our most basic natural resource—the soil. Soil is one of the essentials of life, yet we tend to take it for granted.
Australia will be unable to maintain its food exports, achieve water security or meet its greenhouse targets without a major improvement in soil management.
Soil structure and fertility (soil health) is fundamental for food production. The soil contains 55 per cent of Australia’s terrestrial carbon store (the other 45 per cent is in vegetation). Healthy soils retain, store and filter water resources, reducing run-off (i.e. floods), absorbing waste and recharging groundwater aquifers. The recent flooding in Queensland is in part a product of hard, compacted bare topsoils over large areas after years of drought. We can’t achieve healthy rivers or wetlands, or clean run-off into the Great Barrier Reef lagoon, or resilience for farm businesses and rural communities in the face of hotter, drier and more frequent droughts, without good soil management in our catchments.
One of the most fascinating aspects for me of the climate change debate is not water, or energy or greenhouse gas emissions per se, but the intersections between them. They are usually characterised by wicked trade-offs. For example, many of the prescriptions to improve water supplies, such as desalination plants or pipelines, require large amounts of energy. Biofuels to improve energy security use large amounts of water and land (and energy in their full production cycle). Reforestation for carbon sinks also requires energy and land, with more or less impacts on water resources depending on where it is located within a given catchment.
In this very tricky context, improving soil management delivers win-wins all round.
Improving soil organic matter (carbon) content should be a priority goal for public policy. While it can be achieved in certain defined areas though direct application to soil of imported organic waste materials, at a broadacre scale it is achieved mainly through farming systems that maintain higher levels of groundcover, retain trash and stubbles, and usually place more emphasis on the use of perennial plants.
Increasing soil carbon levels increases water holding capacity. It reduces run-off and hence flood risk. It obviously increases carbon storage and reduces soil emissions. And it almost inevitably improves soil structure, fertility and drought resilience. The potential gains from using improved varieties or GMOs are likely to be minimal in the absence of good soil management. Good soil management can make the difference between getting a harvest and not getting a harvest in a poor season, or between minimal erosion losses and major land degradation during drought or flood. Wellmanaged soils recover and respond quickly after drought, enabling businesses to restore profitability sooner.
Given all of the above, the average Australian citizen and taxpayer might expect that soil management would be a very high priority for primary industries and governments at all levels.
However benign neglect would be a reasonable summary of the status quo.
Soil conservation extension services have been run down, the teaching of soils at tertiary levels has declined, soil resources monitoring programs are patchy and fragmented, like the overall soils information base, and we lack user-friendly tools for people to measure soil carbon. We are unable to determine in a nationally consistent manner with any authority, whether the condition of our soils is improving or deteriorating. We accept without question the need for good economic data to inform economic policy decisions, yet we continue to under-invest in fundamental national data about natural resources like soil. While there is a strong demand for soils information, in most regions it is difficult to find people with the know-how to access and interpret existing information. Soils research is similarly fragmented and underresourced and lacks the capacity to be generating the knowledge we will need to improve the management of Australian soils in even more challenging climatic conditions.
Soil protection under the Australian Constitution is unambiguously the responsibility of the States and Territories, however as with other natural resource management issues, the Commonwealth has become increasingly involved over the last 25 years.
There is a new spirit of cooperative federalism in the air, which will be sorely needed as we face compelling policy challenges in developing a long term national approach to water, food and energy issues. The time is ripe for a coherent, genuinely national focus on improving soil management. This would deliver benefits for consumers, for farmers, for rural communities and for the environment.
Reprinted with permission by Andrew Campbell. Campbell is a sustainable natural resource management consultant. He was previously chief executive officer of Land and Water Australia and a senior executive in the Australian government. Campbell manages a family farm near Cavendish, Victoria, Australia, with the help of a neighbor. Campbell's Website: http://www.triplehelix.com.au/.
Man-Induced Soil Erosion on the Southern Piedmont by Stanley W. Trimble is now available in an enhanced new edition. New typography and high quality print production make this edition of the book essential even for those who still possess one of the greatly sought after copies of the first edition, which is now out of print.
