image of soil

SOIL - KEY TO LANDSCAPE REGENERATION

By restoring the structural, mineral and biological health of our soils we can rebuild the resilience of our landscape and better mitigate the landscape degradation and global challenges currently being faced. For effective regenerative landscape management, our soils must be managed in an integrated way with our water and vegetation resources and our biodiversity.

Why address soil health?

Healthy soils are essential for healthy plant growth, human nutrition, drinking water filtration and a landscape that is more resilient to the impacts of drought or flood. Healthy soil helps to regulate the Earth’s climate and stores more carbon than all of the world’s forests combined. Maintaining soil health is critical for biodiversity - a handful of fertile soil contains more microorganisms than human beings that have ever lived. Two-thirds of Earth’s species live beneath its surface.

Soil organisms contribute a wide range of essential services to the sustainable function of all ecosystems. They act as the primary driving agents of nutrient cycling, regulating the dynamics of soil organic matter, soil carbon sequestration and greenhouse gas emission, modifying soil physical structure and water regimes, enhancing the amount and efficiency of nutrient acquisition by the vegetation and enhancing plant health. These services are not only essential to the functioning of natural ecosystems but constitute an important resource for the sustainable management of agricultural systems [1].

The carbon content of soil is one of the key indicators of its health and is a master variable that controls many of these processes. It is the carbon content of soils that largely governs their capacity to absorb, retain and supply moisture within the soil and to sustain active plant growth. Every gram of carbon in the soil can retain up to eight grams of water.

Image of mycorrhizal fungi

Mycorrhizal fungi thrives in healthy soils,
  enhancing the ability of plant roots
  to access soil moisture and nutrients.

Soil carbon helps support a healthy balance of nutrients, minerals and soil microbial and fungal ecologies, improving soil fertility. It promotes the sustained production of essential food and fibre as well as the capacity of plants and animals to resist disease, insect infestation and climate stresses. Increased soil carbon levels therefore also have the means to reduce our reliance on costly fossil fuels and other farming inputs.

However, current rates of soil erosion by wind and water across much of Australia now exceed soil formation. Research from the CSIRO released in July 2013 indicates that Australian soils are losing about 1.6 million tonnes of carbon per year from wind erosion and dust storms alone (read more here). Across Australia’s dryland cropping and grazing sector it would be unusual to find actively farmed soils with a carbon content of greater than 1.5%. Ideally, soil organic carbon levels for quality agriculture should be around 5%.

Currently on both the 1.5 billion hectares farmed globally and the 40 million hectares farmed in Australia, we are:

  • losing 1-20 tonnes of topsoil for every tonne of food produced
  • losing 5-10 tonnes of carbon per hectare per annum through current farming practices

Soil health is such an important issue that the UN General Assembly declared 2015 as the
International Year of Soils and each December 5th as World Soil Day.
Follow the links to learn more...

So how do we fix soil health and increase soil carbon?

Image of farmers discussing the value of healthy soil

Farmers discussing the value of
  healthy soil at a Soils for Life Field Day.

Land management practices can either accelerate or moderate soil degradation. We need to change our practices to reverse the current downward trend. For example, ploughing was seen as good agricultural practice for thousands of years. However, it is now known that the more often land is ploughed, the faster it loses essential organic matter and the biological activity it supports. Zero and minimal-tillage practices are now much more common. We now also need to focus on more than just the conventional N,P,K fertilisation programs and ensure we are addressing the full structural, mineral and biological health of our soils in order to receive all the benefits healthy soil can provide.

When applied to agriculture, holistic principles enhance soil health and optimise humate formation from the bio-mass produced rather than increase oxidation which destroys the critical elements of soil, such as fungi and microbes, which are fundamental to soil sponginess and its ability to produce nutrition rich plants and crops.

To start this we need to regenerate the formerly high organic matter of our soils and healthy microbial communities. We need to:

  • increase organic matter in soils through increasing groundcover, vegetation, mulch, composts...
  • use vegetation intelligently within managed landscapes to protect soils from the effects of wind and salinity
  • practice minimal tillage and retain crop stubble
  • implement time-controlled planned rotational grazing (such as Holistic Planned Grazing)
  • use bio-fertilisers
  • aim to have 100% groundcover, 100% of the time
  • encourage biodiversity - above and below the soil
  • support and protect soil microbial ecologies, including fungis
  • reduce dependence on increasingly expensive fossil fuels and non-organic fertilisers and bio-cides

Learn more about the importance of soil health and how it can be achieved on the Healthy Soils Australia website.

Read our blog posts for further information on the importance of our soils and how some farmers are improving soil health and profits. Read more about these innovators in our case studies and adopt regenerative practices on your property.


Find out more about the other key factors in landscape regeneration - water, vegetation and biodiversity.

Sources: http://www.fao.org/soils-portal/en/
[1] http://www.fao.org/soils-portal/soil-biodiversity/en/