SOIL health and soil carbon have become farming buzz words, with farmers taking a bigger interest into the science behind their soils in recent years.
Last Sunday, 30 people gathered at the Katanning New Lodge Motel to listen to Resource Consulting Services (RCS) co-founder Terry McCosker discuss issues surrounding soil health.
Dr McCosker said a farm’s ecosystem was made up of four main parts – people, land, production and business.
Within those categories there were different subsections that made up a farming operation, with soil health and carbon forming part of the land component.
“Carbon is the beginning and end of all life and it’s a form of energy,” Dr McCosker said.
“The carbon cycle is 375 million years old.” Dr McCosker said photosynthesis – or carbon intake – occurred in birth, growth and reproduction, while oxidation – or carbon release – occurred through death and decay.
Every living organism processed carbon in this way, therefore when plants or crops were going through the oxidation stage, it was important to make sure they released carbon into the soils. Dr McCosker’s presentation was broken down into two sections – carbon credits and soils 101.
After a brief description on how carbon worked within soils, Dr McCosker explained the carbon credits system which is a nationally recognised program.
Carbon credits provide a mechanism to return additional income to landholders, with the Federal government and big emitters purchasing the credits.
The 25-year project is a one-off deal with the government, where a farmer can produce records of carbon growth and sell that growth for a dollar value.
However, there are downsides to the deal, with no financial return for the first five years.
“You pay for the first test of your soils and then the second test five years later,” Dr McCosker said.
“Then maybe you will see some income if your soil carbon has improved.”
Although what you produce is worth more on the market, with one tonne of soil organic carbon produced on farm equating to 3.67 tonne of carbon dioxide on the market.
“You can’t get a substantial amount from trees and forestry alone,” Dr McCosker said.
“Finally soil carbon has the possibility to be controlled.”Dr McCosker said the four key drivers of carbon return were sequestration rate (tonnes of carbon produced per hectare, per year), the price of carbon, the cost of measurement and the scale of the project.
He said a small property of 500ha may not be viable, but a property near 1000ha or more had a chance to make money off of soil carbon.
There are numerous terms and conditions with the project, but one downside which shocked people in the crowd was the fact it couldn’t continue on as part of the succession plan.
The project deal is a one-off 25-year deal, meaning once the term is finished there is no chance to continue selling the carbon product.
But Dr McCosker said it shouldn’t be seen as a negative due to the positive impacts the project would have to soil health.
“Soil health is a function of physical attributes and chemical balance,” he said.
Between 80 and 90 per cent of the total nutrients for growth come from the atmosphere with only 10 to 20pc of nutrients coming from the soil.
Dr McCosker said there were six principles of regenerative farming and plant production that farmers needed to consider. Number one was to plan, monitor and manage soil health, which included giving nutrients to the soil only when necessary.
He said soil had a natural carbon to nitrogen ratio of 12:1.
“It doesn’t matter how much carbon you have and how much nitrogen you put on, the soil will control the ratio and search for carbon somewhere else,” he said.
When the soil sought carbon elsewhere it was pulled out of essential parts of the soils biology, decreasing the health of the soil.
“You will not build carbon if you put a heap of artificial nitrogen on your soil because of the ratio,” he said.
The second principle was to maximise living plant production, looking after the soil’s biology and giving plants the chance to thrive without the use of unnecessary chemicals.
Tying in with that was number three, with a focus on biology which Dr McCosker said would repair soil health and increase the amount of fungi and bacteria.
Introducing biodiversity was number four, which included spreading compost on crops and increasing the amount of plant varieties you grow at once.
Ground cover was the fifth principle of regenerative farming, and was all about protecting the soil and its biodiversity.
Dr McCosker said producing underground organic matter was harder with an annual crop than with perennials.
“Annual crops grow a shallow root system, whereas a perennial root grows deep into the soil,” he said.
The deep roots will allow for more matter to protect and thrive the soil’s biodiversity.
Finally, Dr McCosker wanted attendees to know that livestock were natures recyclers.
He said a good rotation with livestock would help bring different biology and organic matter to the soil, which would assist in the growth of healthy soil.
“The base of changing things is management – so grazing, cover, crop rotation, aeration and landscape hydration,” Dr McCosker said.
“Then you need to look at the biology, catalytic inputs and the biodiversity, including adding essential nutrients such as boron, sulphur and calcium.”
He said the benefits of increasing soil carbon included improved soil health, increased water holding capacity, enterprise risk hedge, better management of price and drought risk, and increased carrying capacity and yields.
“Yields will go up 12pc for every 0.5pc change of soil carbon.”