Published: 11 Mar 2022
Imaging traditionally used in space exploration and defence will be harnessed to capture the impacts of regenerative agriculture as part of a trial to improve future drought resilience in Tasmania’s south-east.
The project aims to assess the impact of regenerative agriculture (regen ag) on animal welfare, soil carbon, landscape function, pasture biomass and long-term agricultural sustainability and includes researchers from the Tasmanian Institute of Agriculture (TIA), the University of Tasmania, Enviro-dynamics, the Regenerative Agriculture Network of Tasmania (RANT), Cibo Labs and others.
The project will also develop new approaches for merging imagery from drones and satellites to develop new digital approaches for managing livestock from afar. These approaches will reduce labour and time required from farm managers.
The project will use several imaging tools, including drone and satellites to conduct hyperspectral imaging (a technique that analyses a wide spectrum of light to provide more information on what is imaged), to collect digital imagery of grasslands at Okehampton, a sheep grazing property near Triabunna, with a goal to optimise pasture management, improve how the landscape functions and improve drought resilience.
Systems Modelling Team Leader at TIA Associate Professor Matthew Harrison leads the research team, which includes Dr Steve Harwin, Dr Darren Turner, Dr Phil Tickle (Cibo Labs), Celia Leverton (RANT), Peter Ball (Enviro-dynamics), and Jason Whitehead, the owner of Okehampton.
“The purpose of these trials is to examine the effectiveness of regen ag and cell grazing relative to conventional grazing and to develop new methods for remote monitoring of grazing management using drone and satellite imagery,” Associate Professor Matt Harrison said.
“The project will use drones to quantify pasture biomass removed by grazing, and these algorithms may be later used to enhance real-time management for farmers via decision support tools, as well as enhance existing satellite-based approaches to improve the production of pasture biomass removed at the paddock level.
“Ultimately, these technological innovations will improve the timeliness of grazing management using remote approaches.
“In concert with regenerative agricultural approaches, the technology will improve ground cover and productivity, as well as animal welfare, which collectively can lead to improved sustainability.”
Assoc Prof. Harrison's is internationally renowned for his work in sustainable agricultural systems, including the influence of climate change and extreme climatic events on crop and animal productivity, use of seasonal and intra-annual weather to forecast plant growth, model derivation and evaluation, and on-farm management strategies to mitigate greenhouse gas emissions from agriculture.
He is also the Director of the Carbon Storage Partnership, a multi-million-dollar transdisciplinary initiative that is developing profitable, environmentally sustainable, and socially acceptable pathways to a carbon-neutral livestock sector by 2030.
The TIA-UTAS team will integrate satellite imagery with footage captured by drone pilot Darren Turner, as well as calibrate and/or validate pasture data provided by Enviro-dynamics.
At Okehampton, Jason Whitehead has overseen the installation of infrastructure needed for the cell grazing trials by pakana Services and staff from Glamorgan Spring Bay Council.
Previously Okehampton had been continuously grazed over large paddocks at light intensities for longer durations. With new fencing and water infrastructure now in place, about 2000 Merino sheep will be rotated through a series of plots over the 18-month trial, which is due to finish in June 2023.
Ground control points have been placed at the corners of the paddock so when the drone flies over it is picking up the exact point as the on-ground data collection.
“That can then be scaled to the drone and the drone is flying with the same sensors as the satellite, so we can scale up,” Mr Whitehead said.
“We are trying to work out from the satellite imagery dry and green biomass amounts. That is the end point. And the regen ag grazing highlights the importance of having the right kind of stocking density, rate, and rotation.
“We are working toward being better at looking after our pastures, but also a more cost-effective agistment arrangement with our farming tenants, so we have cash flow and reduced costs associated with pasture regeneration and reseeding.
“Ultimately, we are working toward a whole of property management plan.”
Celia Leverton, President of Regenerative Agriculture Network Tasmania (RANT), has farmed for 40-plus years and said the regen ag approach has tipped everything that she has learnt “on its ear.”
“We know these systems of grazing work because they have been tested in many varying climates, rainfalls and on different soil types,” Ms Leverton said.
“Past trials and whole of farm demonstrations has shown it builds drought resilience by increasing water infiltration and nutrient cycling and the moisture retention on the soil.”
Regenerative agriculture practices restore landscape function, increase nutrient and water cycling and sequester carbon in the soil. These practices increase biodiversity, productivity and are profitable and low risk, while being personally sustainable for farmers and their communities.
Grasses are left to fully recover between grazing events ie. it has no grazed tips and 2-3 fresh yellowing leaves. The yellowing leaves are pushed onto the soil surface between the perennial grass bases to become decomposing litter, which then increases the water infiltration and soil moisture holding capacity.
The decomposing litter also triggers the nutrients to cycle biologically, increasing the soil nutrient access through aeration and improving soil microbial activity. This may also improve soil organic carbon, which can then reduce net farm greenhouse gas emissions.
The combination of increasing the organic matter in the soil - because grass is recovered – and the impacts under hoof of higher stock densities (that push uneaten grass down into the soil) and high pasture utilisation, are being monitored at Okehampton.
“The sheep tend to eat the green and some of the dry out of the grass and push the remaining dry matter onto the soil surface. That provides litter on the soil surface which decomposes, enabling those other functions to happen,” Ms Leverton said.
“So, instead of seeing that grey oxidising grass - which is commonly seen across grazing country - it pushes it onto the soil surface where the soil biology can access it and it is not releasing carbon into the atmosphere.
“While it is not all going down the animals’ throat, it’s not being wasted. The remaining vegetation is feeding the soil. You get the animal performance while building the landscape function.”
She said the monitoring system, known as landscape function analysis, is based on the peer-reviewed work by Dr David Tongway, from CSIRO, and has been used extensively across Australia by farmers and universities. From there, Holistic Management educator Graeme Hand developed a process to provide corrective action and feedback to farmers.
“There have been hundreds of trials done around Australia and the results have been consistently positive Ms Leverton said.
Trial results have shown that leaf driven recovery allows landscape health and biodiversity to reach 20% of its potential, while root driven recovery is delivering 60% of the potential.
“It is not a terribly convenient form of management – it requires redistribution of labour to animal management – but it takes resources from cutting hay or silage or fertiliser application.
“Not all animals are going to be suited to it, but farmers have proven it is possible to breed animals that thrive on the fully recovered grass and we can move to that phenotype of animal at a profit. This grazing system increases landscape health while producing food and fibre. It uses less fossil fuels and is a lower risk system for the environment and the farm business.
“We are very conscious of animal welfare and performance issues as well - their welfare is primary. But also getting enough utilisation and impact on the ground, so what is not eaten is pushed down. That is building that soil health as well.”
Ms Leverton said the grazing system is in use on the mainland, with some farmers producing a kilo of beef for 20-30 cents, compared to around $2 per kilo for standard grazing practices.
“The low cost of production means it doesn’t matter whether it’s a dry or wet year, it doesn’t matter what the market price does, these farmers are always ahead. They are always profitable. And moving away from the emphasis solely on production, to a profit and land health focus.
“Farmers are taking back some of the profits made in agriculture and reducing their financial risk, as well as the risk to the land.
“We need more data. While it has been proven anecdotally that high stock density and grass utilisation, with a long recovery delivers an increase in landscape function and profit, we need repeated trials to build a body of evidence that farmers can be confident in and will attract funding to further expand trials.
“Currently we have around 30 small trials and paddock scale trials established around Tasmania, and they are all feeding back the same information that the high density, utilisation and longer recoveries rapidly increase the landscape function and health. We plan to expand these trials even further and would love to hear from more interested farmers.
“This is what the beauty of these trials is. They are a small area so it is a low-risk check to see what will for on individual farms.
“Saying that, we are not attached to any particular practice, but are outcome focused on increasing the ability of our farming landscape to function to its biological potential, while being profitable.”
A recipient of a Churchill Fellowship, Ms Leverton will travel to Canada, Mexico, and the US in the next year to visit farms who have successfully adopted regenerative farming and increased their landscape, business, and farmer health in the long-term.
“I’m also visiting research and education facilities to bring back some of the processes that have been successful in enabling the uptake and funding of regen farming.”
This project is being delivered in partnership with Cape Herbert Pty Ltd, Regenerative Agricultural Network Tasmania, the Tasmanian Institute of Agriculture, the University of Tasmania, Enviro-dynamics, Cibo Labs, Glamorgan Spring Bay Council and pakana Services, and with assistance from Grindstone Pastoral (current farm lease holder). It is jointly funded through Australian Government’s Future Drought Fund and Cape Herbert Pty Ltd.
IMAGE: Installing fencing at Okehampton.
This article was published in Tasmanian Country Newspaper on 11 March 2022.