The impact of greenhouse gases (GHG), emitted from human activity, on the climate has, of course, been widely discussed.
Additionally however, environmental degradation through cultivation and deforestation not only releases carbon from the biosphere, but has also disturbed the balance of the carbon cycle. Against this background the membership of Agri-Tech East, which includes scientists, farmers and technologists, is looking closely at ways that ‘sustainable’ agriculture can be part of the solution.
Agriculture as emitter and sink
Carbon dioxide is a major GHG and the contribution of other types of gas is given as ‘carbon dioxide equivalents’ to enable comparisons.
Altogether emissions from UK farms amount to 45.6 million tonnes of carbon dioxide (CO2) equivalent a year – about one-tenth of UK GHG emissions.
However, in contrast to other industries, only 10% of the GHG produced by agriculture in the UK is CO2[i]. Around 40% is nitrous dioxide (N2O) from synthetic fertiliser use and 50% is methane (CH4) released by animals and rotting vegetation.
Therefore, reducing the use of fossils fuels and waste offers the opportunity to reduce emissions whilst increasing the productivity of farming.
Dr Belinda Clarke, Director of Agri-Tech East – recent hosts of the REAP conference – says: “Our members are farmers, technologists and researchers, and a key topic of discussion is always how to use agri-tech to improve the profitability and sustainability of agriculture in ways that are also good for animal welfare, and both human health and that of the planet.
“Of particular interest are ways to improve soil health, better manage reserves of fresh water, and decrease reliance on artificial fertilisers and plant protection products.
“Fertilisers and other agri-chemicals are a major cost to the farm and also have other impacts – including pollution from nitrogen run-off into watercourses and a detrimental effect on beneficial insects – so reducing usage of these products would have benefits on many levels.
“Innovation is about finding solutions to problems and this often happens at the ‘intersections’ where different perspectives give new insights. The idea at our recent conference was to get people thinking about the dynamic between the natural and cultivated environment as an integrated system, with nutrients cycling between the different functions and where change in one aspect creates an effect on other elements in the system.
“It is crucial in food production that policy is underpinned by sound science. However, there are still considerable gaps in knowledge and this is hindered by a reductionist ‘silo’ approach that has been adopted by the scientific community in the past; good solutions require a cross-disciplinary approach.”
The adoption of new technologies and approaches is inherently risky, so a new report by the international Food and Land Use Coalition has been welcomed by many agricultural and food scientists.
With the title ‘Growing Better: Ten Critical Transitions to Transform Food and Land Use2 the report gives recommendations supported by three key financial consideratons; the potential economic gains, the annual additional investment needed, and the business opportunities by 2030.
The numbers are compelling for those considering investing in agri-tech. For example, achieving productive and regenerative agricultural systems is going to cost an estimated $35-40 billion by 2030. But the projected economic gains are a massive $1.17 trillion with new business opportunities around $530 billion.
Dr Clarke comments that it is, possibly, the first time that the return on investment in agri-tech has been expressed in these terms and that it provides a big step forward for the industry, the sustainability of food systems and the health of the planet.
Five ways to achieve net zero in agricultural science
1. Improving soil health
Measures to reduce tillage (ploughing) will enhance soil ecosystem and organic content, additionally they reduce the use of heavy equipment which causes compaction and damage to the soil structure. However, currently these cultivation techniques rely on the use of herbicides.
A new hopping robot that can identify, map and kill weeds for hours at a time, with minimal supervision, was launched by UK start-up HayBeeSee at REAP.
Drones are becoming more widely used in agriculture, but there are limitations on their usage. HayBeeSee co-founder Fred Miller has a family farm in Nebraska, USA, and trained as an aerospace engineer. He has developed a whole new classification of vehicle using the cutting-edge concept of a jumping robot with a quadcopter underneath to help it hover a short distance above the ground.
The jumping-quadcopter could cut farmers’ herbicide usage by 50% or more by increasing the precision of application, and would reduce fossil fuel use by removing the need for tractor-driven spraying.
This response could include the closely targeted application of herbicide.
“The majority of herbicides used today act upon the weeds in a small number of ways and this has resulted in evolutionary pressure towards weed resistance,” explains Professor Liam Dolan, who is the Sherardian Professor of Botany at the University of Oxford and co-founder of MoA Technology. “What is needed is a more diverse tool kit with a variety of different chemistries that can be used alongside non-chemical measures to provide sustainable crop protection.”
MoA Technology is offering a radically different approach to herbicide development that uses insights from evolutionary biology to offer new modes of action. The company has developed a crop protection discovery platform to find new herbicide leads.
Professor Dolan says that its rapid screening process, which uses both whole plants and active ingredients, should fast-track the development of effective herbicides with low environmental impacts.
“We have developed a really neat technology that allows us to rapidly screen naturally occurring and synthetic molecules to identify potential new herbicide leads that work in different ways. We can screen their efficacy against entire plants using imaging processing, then from this we can get a lot of information about how the molecules are killing the plants and use this to identify new targets.”
By developing herbicides with different modes of action, MoA Technology is confident that it can break the herbicide ‘arms race’ and provide more sustainable solutions to farmers.
“The Holy Grail would be a herbicide mixture that combines multiple, new modes of action that control weeds and minimises the chance of resistance evolving. Only small amounts would be needed because this mixture would be highly potent and with the advances in precision spraying it could be applied only where it was needed,” Professor Dolan concludes.
2. Carbon capture and storage
Land may be utilised differently to increase carbon storage and also to increase food resources for pollinators. Actions can include introducing cover crops to reduce loss of nutrients from bare ground, and planting and protecting grassland, hedgerows and trees that lock-up carbon.
Sarah Barnsley is currently completing a PhD at the University of East Anglia, in collaboration with HL Hutchinson Ltd, looking at how foraging resources can be managed for pollinators at the whole farm scale.
1,000 pollinator species within the UK contribute millions in terms of increased crop yield. However, the widespread use of monocultures means that at times of the year there is little food available.
Sarah comments: “We are using remote sensing technologies to identify various wildflower and hedgerow species and therefore the availability of food on-farm. This way we are able to identify any gaps that need to be filled either spatially or temporally.
“By improving the food supply for pollinators as a whole you could enhance pollination services and crop yield. Putting some cropped land towards suitable habitat for wildlife doesn’t have to affect profitability either, if you take the low producing parts of a field out, for example the hard-to-reach corners of a field.”
A study published in 2015 by Pywell et al3 demonstrated that by converting up to 8% of unproductive cropped land to habitat, the same level of productivity could be maintained overall.
3. Renewable energy and recycling waste
EcoNomad is offering a ‘waste to energy’ solution to make biogas production accessible for smallholders.
Anaerobic digestion (AD) turns waste into biogas and a nutrient-rich soil additive that reduces the need for inorganic fertilisers – but the current solutions are too complex and expensive for smallholdings.
Ilan Adler, co-founder of agri-tech start-up EcoNomad, has re-engineered AD technology to create a more affordable option that uses passive heating methods and naturally occurring bacteria.
4. Healthier livestock
Cow burps have been slammed as a major cause of GHG, but how much methane is produced and can it be reduced? These are the questions being addressed by agri-tech start-up Zelp, which has developed a way to capture methane emissions and oxidise them in the field.
Co-founder Francisco Norris says that methane production provides information on how efficient individual cows are at digesting food and converting that energy into milk or mass. It can also highlight health issues with the animal, a failure to thrive or bacterial infection.
“The majority of livestock production in the UK is on grassland, so it is not possible to adjust the feed to reduce emissions. We have developed a technology that can detect when the cow burps – exhaling methane at high purity – and captures the gas to convert it to CO2 and water, reducing its global warming potential by a factor of 85.
“Before Zelp it was not possible to access this information. We are looking at how methane production differs between different breeds and the impact of diet. Potentially we will be able to correlate the emissions to heat, oestrous and calving and to a number of different value adds for the producer.”
Healthy lower weight cattle, finished rapidly to meet buyers’ specifications, produce less methane emissions over their lifetime, so giving farmers the tools to decide which animals in the herd produce the best male calves for dairy beef would also reduce waste and greenhouse gas emissions.
Breedr, developers of a precision livestock app, together with Rothamsted Research North Wyke ‘Farm lab’, have analysed six years of real-world data to develop ways to find the point of ‘peak profit’ for producers.
Dr Andrew Cooke, livestock scientist at Rothamsted Research explains: “An animal will consume about 2.5 per cent of its body weight a day in dry matter. It is accepted that dry matter intake correlates strongly with methane output – a greenhouse gas.
“Therefore, you may have two animals that are the same weight at slaughter, but if one of those gained more of its weight earlier in its life, it will have consumed more food and produced more methane during its lifetime.”
Ian Wheal, founder of Breedr, comments: “Growth curve analysis offers the potential to estimate the gross feed consumption and emissions of individual cattle, enabling a deeper understanding of the economic and environmental efficiency of livestock production.
As animals get larger their efficiency decreases, so giving farmers the tools to make the decision when to send an animal off would improve profitability and reduce GHG emissions.
The precision livestock network created by Breedr aims to streamline and incentivise livestock production – increasing profitability while reducing environmental impacts and overfeeding.
5. Genetic improvements for crops
Improving disease resistance in crops will increase yield in the field. “I see great potential for gene enhancement; it will enable us to become more efficient in reducing crop loss, and this will in turn have a positive impact on sustainable agriculture,” says Dr Brian Rigney, a scientist at the 2Blades Group, part of The Sainsbury Laboratory in Norwich.
“In the future, we will be able to produce more crops with fewer chemicals and protect the environment. Efforts in plant breeding in the mid-1900s gave rise to the green revolution through the development of better performing crop varieties. Now it is crop diseases that have become the limiting factor of crop yields.
“Research at The Sainsbury Laboratory has identified multiple key traits in the plant genome that will help reduce crop losses through disease. This discovery has the potential to improve yields and reduce the impact of toxic chemicals on the environment and the farmer.”
1. NFU report ‘Achieving NET ZERO Farming’s 2040 goal’: www.nfuonline.com/nfu-online/business/regulation/achieving-net-zero-farmings-2040-goal