Mission to boost soil carbon
• AgriProve soil carbon field officer Theresa Chapman. Photo supplied.
By Daisy Baker
October 14, 2020
Regenerative agriculture is a growing trend across the world and Winnaleah’s Jarrod Smith has poured hours of his time into researching on-farm benefits in recent years.
When he saw that AgriProve were assisting farmers to adopt new practices and technologies to reduce their emissions and earn carbon credit units in return, he was keen to get involved.
“I’ve had a keen interest in regenerative agriculture for a while now and the greatest metric to measure soil health is soil organic matter (carbon),” he said.
“If there’s a way to get a monetary benefit from doing it, that’s an added bonus.”
He has been experimenting with regenerative practices in recent years but hopes upping his efforts through this project will increase production and make a positive difference to long-term soil health.
Mr Smith has signed up for the project and is awaiting the first soil sample to be taken on his farm.
There is currently one approved project in Tasmania and 17 Tasmanian project registrations awaiting approval from the Clean Energy Regulator.
AgriProve soil carbon field officer Theresa Chapman said once farmers have registered an expression of interest, AgriProve works with them to map out a project area and after approval has been granted, the first core samples are taken.
“We come in with soil testing rig and take a series of soil cores from across the area and that’s where we get the baseline soil carbon reading,” Ms Chapman said.
“Three years after that, we come back in and get a soil carbon measurement and measure that against the baseline and that’s where you generate your credits from.
“Farmers can them take their carbon credits to market and that’s when they get cash. At that point, you can choose whether or not to sign on to the project for 25 years.”
She said most landowners will get an initial soil carbon reading in the one to six per cent carbon range.
“Over 100 hectares and 300mm depth, raising the carbon level from 2 per cent to 2.5 per cent might not sound like much but it’s quite a lot of extra carbon you’re sucking out of the atmosphere.”
Ms Chapman said there are few restrictions and it’s entirely up to farmers what strategies they use to improve carbon soil levels.
“One method we think is successful and has proven to be successful in Gippsland is using a Soilkee which is a particular kind of pasture renovator used to introduce a diverse range of species into perennial pasture if you’re a grazing operation,” she said.
“It can sow diverse things like sunflowers and tillage radish which means you get all different kinds of root systems, deeper penetration of roots and increases the diversity of soil biology, which is really the driver of the carbon process.”
She said other beneficial practices can be improving soil nutrition or liming to raise PH, or changing set stocking to rotational grazing, keeping the plants leafier and promoting a healthier root system which is important for the carbon draw down.
Mr Smith said one of the main things he’s implementing is plant diversity.
“I’m doing some trials this year, without spraying anything off I’m direct drilling varieties like turnips, beans, clovers, cereals and brassicas, directly into established pastures. These will be used for grazing,” he said.
“Another one is minimising soil disturbance, that’s what we’re doing with zero till planting maize crops.
“We’re also using less chemical fertiliser, instead using our own homemade compost made of farm waste, which is kinder on soil biology.”
He said by trialling these practices on his farm over a period of time, he’ll see the impacts they have on soil health long-term.
“The expectation is that soil carbon levels will increase which by the end of it we would be hoping to get paid for.
“I’m keen to continue the practices well past this project,” he said.
“My goal is to leave the land that I’m a caretaker for in better condition than when I found it.”
AgriProve aim to register 30 plus new soil carbon projects in Tasmania by the end of 2020.
In the long term they hope to run soil carbon projects on 15 per cent of viable Tasmanian pasture land which equates to 150,000 hectares by 2025.
“Where the carbon market is at the moment, it’s unlikely to be highly lucrative but you get to know that the practices you’re doing are boosting soil health and productivity, and you’re part of the solution, so it’s a great thing to pursue,” Ms Chapman said.
“Hopefully over coming decades market value increases as the need for atmospheric carbon action becomes more acute.”