Last year the General Assembly of the United Nations designated 2015 the International Year of Soils, and declared 4 December will be World Soil Day. Last Parliamentary sitting week I moved a Private Members Motion marking the importance of the UN’s declaration.
The UN's motivation for a call for greater focus on soil health is obvious. The nutritional value of the food we eat is largely determined by the health of the soil in which it grows. Soil is of course the basis for food, feed, fuel and fibre production and for services to ecosystems and human wellbeing.
Soils play a key role in the supply of clean water and resilience to floods and droughts. The largest store of terrestrial carbon is in the soil; therefore its preservation will contribute to climate change adaptation and mitigation.
The maintenance and, indeed, enhancement of global soil resources is essential if humanity's need for food, water, and energy security is to be met. It is well known that it is now predicted that the world's population will grow from 7 billion to some nine billion by 2050.
Since European settlement, many of the farming methods that have been embraced here in Australia have degraded our soils. Thankfully, we have largely learned from those mistakes in more recent decades and have adopted more enlightened methods, such as low or no-till farming practices and reducing our reliance on fertilisers. An army of people working with our natural resource management groups, including through Landcare projects, have for decades now been helping to better manage the land and river ways that feed us. But much more needs to be done.
The former Labor government recognised this, and in 2012 created the position of Advocate for Soil Health. Former Governor-General Major General Michael Jeffery still holds that position and is doing an outstanding job.
I am confident that Major General Jeffery would not mind me saying that in my experience—having had many conversations with him—he is often frustrated by the lack of attention our soils receive from our policymakers. As he points out, our current approaches to water management are focused mainly on the—on average—12 per cent of rainfall that ends up in our streams, our rivers and eventually our dams—in other words, the water we actually see. Another two per cent falls on our rooftops and roads. However, the greatest potential for efficiency lies in making better use of the 86 per cent of rainfall initially falling on our soils, of which a staggering 50 per cent—or 25 times the quantity held in all of our dams—wastefully evaporates because it cannot filtrate the landscape.
This is where the importance of organic carbon in soils comes in. A properly structured soil with appropriate carbon content will allow rainfall to penetrate and to be initially stored in-ground for use by plants and animals. It will also allow the water to filter slowly, recharging our waterways, particularly during times of limited rainfall.
Dams and other water storage are generally very important, but when you think about it there is much more we can achieve through innovation, technology, research and development in the area of soils.