Following my recent blog exploring the opportunity that regenerative agriculture offers as a shared ambition for the food and farming sector, here, I share eight questions I’m currently holding about regenerative agriculture.
A little context. In addition to my work at sustainability non-profit Forum for the Future, I’m excited to be doing a Nuffield Farming Scholarship to explore the regenerative agriculture movement. So it’s a particular focus at the moment and in this piece, I draw on some of the thinking we’ve already been doing at Forum for the Future.
1) Does it matter if regenerative agriculture means different things to different people?
One thing I’ve learned with my colleagues at Forum for the Future as we’ve explored regenerative agriculture is that it means different things to different people. This is hardly surprising. The term is not protected and it’s a relatively young movement, with advocates across different types of organisations and geographies. So how much does this matter?
Will the term “regenerative” be akin to generic and vague terms such as “sustainable” or “eco”? Or does it communicate a clear and transformative ambition for our farming systems?
Over the next 18 months, I will aim to speak to various farmers and organisations using the term to understand what it means to them. In particular, I want to understand the levels of ambition and how much this differs between people and geographies. I’ll include organisations that have proposed definitions as well as those developing and testing the new Regenerative Organic Standard. As I do this, I’ll draw on the range of other sustainable agriculture movements and philosophies (see below) to find out how people see regenerative agriculture as being distinguished. What, for example, is attracting some people towards regenerative agriculture, but not to organic, which has a much more established history. Ethan Soloviev’s proposed lineages of regenerative agriculture is one useful insight to draw on here.
In exploring this question, I would also like to test a set of common principles and practices (outlined below) related to regenerative agriculture, to understand how much consensus there is around what it means, how this is shifting and whether people think consensus even matters.
2) Can the regenerative agriculture movement uphold a high level of ambition and integrity?
The term regenerative agriculture is occurring with increasing frequency, with farms and companies starting to use the term fairly liberally to describe their approach or ambitions.
Working with the assumption that the scaling-up of regenerative agriculture is ambitious and would be transformative for our food system, there is a danger of the term becoming diluted or losing its integrity as more people use it to describe their ambitions. The risk is higher especially if there is no consensus around measuring what is regenerative. What can the regenerative agriculture movement do to uphold a high level of ambition and integrity?
3) Measuring regenerative agriculture: how do we know it when we see it?
Without using a standard or certification, how do we know when we are seeing a “regenerative agricultural” system? This leads to the question: “how might we measure “how regenerative” a farming system is? Is measuring regenerative agriculture even viable?
This is an important question because organisations working to promote regenerative agriculture are often looking for a consistent means to measure it that works across farms and geographies. Why is this? Perhaps because of the interests to monetise changes in practices (e.g. to create market incentives or enable funding) but also because measurement typically underpins most certification approaches.
To explore this question, I intend to speak to some of the organisations involved in standards and monitoring, such as the Rodale Institute, NSF, the Savory Institute, the Farm Carbon Cutting Toolkit, Sustainable Food Trust, Cool Farm Alliance and Indigo Agriculture. I’m anticipating a spread of opinion as I explore perspectives on this question. For example, for many people, regenerative agriculture is about continually improving soil health and soil organic carbon. But for others in this space, regenerative agriculture might include additional and broader positive outcomes, such as continually improving local water quality, biodiversity and even livelihoods.
Exploring how we measure or witness regenerative agriculture also raises questions related to timescales. For example, some farms are working from a baseline where past management has resulted in highly degraded soils, and now, continual restorative improvements to the soil health and other ecosystem services is very much needed. Other farms might have a long history of sustainable practices and are starting to use the “regenerative” moniker. How might markets and the general public distinguish between the two? How can we have confidence that the benefits from regenerative agriculture (such as carbon sequestration) stick long into the future?
4) Is regenerative agriculture challenging what we grow?
If we are to really embrace the principles and philosophies of regenerative agriculture, I believe it challenges what you produce, not just how you produce it. For example, moving towards more mixed farming systems, more perennial crops and much greater crop and livestock diversity.
However, will the companies upstream who are advocating regenerative agriculture really support their suppliers to increase crop diversity in their farming systems? So far, I haven’t seen much evidence of this happening in practice. It’s an area at Forum we are increasingly trying to focus on with the organisations we work with.
5) Do we understand the barriers to scale?
Through my work with the sustainable nutrition team at Forum for the Future, we have identified various barriers that are preventing regenerative agriculture from scaling-up. These are summarised below. During my Nuffield Scholarship, I would like to explore these further, particularly focusing on the farmer’s perspective and how barriers shift across geographies.
6) The murky world of carbon markets: challenges in measurement and who claims the carbon saved?
The possibility of carbon sequestration is a notable feature for regenerative agriculture. Carbon markets provide a possible route to finance a major transition to more regenerative agriculture. To explore this, I will explore initiatives such as Indigo Agriculture (Project Terraton) and examples such as Mootral’s ruminant feed entering carbon markets. But it is also worth learning from more established carbon markets that already exist, such as the reforestation and peatland restoration (where in the UK, Carbon Codes exist to enable a route for carbon offsetting). One of the many differences with regenerative agriculture is that the benefits from carbon sequestration could be quickly undone in a few seasons of intensive agricultural practice – which is perhaps less of a risk in a reforestation project.
Carbon sequestration in agriculture is fraught with uncertainties and complexity. To briefly explain a few:
Carbon sequestration rates in soil can vary depending on the soil type as well as the practices. Arable soils, for example, tend to have a greater scope for increase than grasslands, while the scope for sequestration on sandy soils can be as low as 2-3%, versus 30-40% for peaty soil.
In trees, carbon sequestration varies with tree species and rates of growth. If those trees are cropped, then the carbon sequestered will depend on the end-use of that timber.
There’s also a plateau with soil carbon sequestration. What happens when that plateau is reached? And how can we be sure that carbon remains locked-in?
We need to be realistic with the maths. As Dr Jonathan Foley explains in this thread, are claims of the huge sequestration potential realistic?
How can we uphold integrity in carbon markets, ensuring a net reduction in carbon and avoid double counting?
7) Exploring strategies to scale-up regenerative agriculture
For many, regenerative agriculture is just another banner for a movement that seeks to transform our food and farming system to work better with nature and provide healthy nutritious food for all. And there are many farmers already practicing it, simply because it’s the right thing to do.
But how do we create the enabling conditions to transform the entire food and farming system? What levers need pulling to bring everyone onto the same path? What does the transition look like?
Deliberately introducing systems thinking lens might help us to explore these questions. Frameworks and theories of how systems change, such as Rogers Innovation Bell Curve, Donella Meadows levers for change, and Forum for the Future’s Scaling Up Impact framework, can help us explore how to support regenerative agriculture to go mainstream.
At Forum, we’ve already started convening organisations across the food system to explore what is required to scale-up regenerative agriculture. In particular, I would like to explore the role of policy/regulation to accelerate change. How necessary is government regulation to scale regenerative agriculture? And in what specific areas is regulation most effective to unlock or promote scale?
8) Based on what we’re learning about mainstreaming regenerative agriculture, what are the different priorities for different actors?
Many different types of organisations influence our food system (as shown in Figure 7) and each has a unique role in supporting or influencing change. But who holds power? Who influences who? Where is pressure exerted? How might responsibility and risk be better shared? What would these organisations look like if regenerative agriculture was mainstream? How can organisations better collaborate to move faster towards regenerative agriculture?
During my Nuffield Scholarship journey, I’m keen to move beyond the theory and return with some practical suggestions to what the priorities should be for different actors in the food value chain to support the mainstreaming of regenerative agriculture.
The journey continues…
So many questions and what feels like messy complexity right now. Thankfully, there are many smart folks out there working on this which I hope to meet over the coming 18 months. With each step of the journey, I will aim to keep writing and hope to get closer to answering some of these questions.
There’s excitement and hope stirring around regenerative agriculture with many organisations putting it into their strategies. So what is regenerative agriculture and could it offer a shared ambition for the food and farming sector?
This is the broad question I’m setting out to explore over the next 18 months in a Nuffield Farming Scholarship. I will visit farming systems and interview organisations across the supply chain that have regenerative agriculture ambitions. I’m interested in how regenerative agriculture is being understood, the types of ambitions and strategies considered for scaling it up – and if it’s scaled, what might our food system look like then?
The Nuffield journey will complement work already taking place at Forum for the Future with various food and agricultural companies, which is exploring the potential around regenerative agriculture and the strategies necessary for it to scale and become mainstream.
Regenerative Agriculture: the latest buzzword or something bigger?
When I first heard the words “regenerative agriculture” many years ago, I didn’t give it much attention. Speaking with others, I know I wasn’t alone in brushing it off as another expression of sustainable farming that wasn’t particularly needed, given that we already have exciting (albeit small) movements in organic and biodynamic farming, natural farming and permaculture. Not to mention carbon-smart agriculture as well as growing recognition around agroecology.
So what sets regenerative agriculture apart and why are several companies starting to take an interest in it?
Perhaps one attractive feature is within its language of regeneration. The enticing idea of putting more back into the environment than we take out. Certainly, the word “regenerative” appears to be becoming a sustainability buzzword within companies, however “regenerative agriculture” should perhaps be considered more specific than a vague aspiration.
Central to regenerative agriculture is the building of soil health and the many positive knock-on effects that this can bring to our farming systems and landscapes. This includes better water management and nutrient recycling, improved yields, business resilience and carbon sequestration. These are all appealing features. For some, it’s the latter benefit, the opportunity to increase soil organic carbon, that is causing a particular stir in some companies, given the increasing pace of climate change.
Figure 1 shows some of the common principles and practices found in regenerative agriculture. When it comes to carbon sequestration rates, not all regenerative agriculture practices are equal. This is outlined well in Eric Toensmeier’s book, “The Carbon Farming Solution” which advocates the particularly impressive sequestration potential of trees (agroforestry) and other perennial crops in regenerative farming systems.
For many advocates of regenerative agriculture, it also speaks to the building of greater diversity in our farming systems and with this, the opportunity to help stop and start reversing the alarming crashing of biodiversity we witness today.
So far the regenerative farming movement has been fairly fragmented. A few companies have been advocating the approach and many of the practices have been pioneered by farmers, where a spectrum of practitioners exist that have embraced the “regenerative” moniker. In a recent article about the movement, Nathanial Short suggested that regenerative agriculture means many different things to different people but it appears to have the power to bring organic and conventional farmers together to work towards environmental outcomes.
Shared definitions and company commitments
Having a shared understanding of regenerative agriculture helps. Over 150 businesses, NGOs and academics have supported this definition of regenerative agriculture proposed by The Carbon Underground:
farming and grazing practices that, among other benefits, reverse climate change by rebuilding soil organic matter and restoring degraded soil biodiversity – resulting in both carbon drawdown and improving the water cycle.
Other definitions exist. For example, Terra Genesis propose a slightly different definition. Last year, my colleagues at Forum found that there were geographic differences in how regenerative agriculture was being understood. For example, in a workshop in India and discussions with people working in different parts of Africa, it was considered important to include positive social outcomes as a principle in regenerative agriculture, broadening the definition. Whereas, in US/UK/Europe, there was a greater focus on environmental outcomes, particularly carbon sequestration and soil health.
The definitions give a sense of the transformative potential that regenerative agriculture promises, and with that excitement, several companies are now grappling with what it means to put it into their strategies. Most notably, both Danone and General Mills have publicly announced it as a major focus. Patagonia and others are working with the Rodale Institute (who coined the term regenerative agriculture) and NSF to create a Regenerative Organic Certification. Ben and Jerry’s, Danone and others have also launched a Soil Carbon Initiative to develop verifiable standards for measuring soil carbon.
New disruptive start-ups are also entering the space, such as Indigo Agriculture and their Project Terraton Initiative, who are creating a marketplace for soil carbon, having recently announced they will start paying farmers up to $15/tonne to store carbon in their soil. On the ground, many farmers are showcasing what it looks like. Gabe Brown’s book “From Dirt to Soil” tells a particularly inspiring set of stories of how regenerative agriculture is transforming farms in the USA to be more profitable, higher-yielding and more resilient businesses, depending less on external inputs such as nitrogen fertilizer.
Systems change for regenerative agriculture
In the five minutes it takes you to read this article, around 100 football fields of tropical forests will have been destroyed (based on a rate of 8 million hectares a year), much of it to make way for monocultural agricultural landscapes. It’s clear that much of our land use today is far from regenerative.
Regenerative agriculture offers a route through which we can make significant progress towards restoration, meeting the Paris Climate Change Agreement and Sustainable Development Goals. But while regenerative agriculture creates a positive stir we must remember that this is a young movement, sitting alongside various other sustainable farming movements. Without robust understandings of what regenerative agriculture looks like in our food system, there’s a danger that some companies will pull out the bits they like, call it “regenerative”, but continue largely with business as usual.
The context-specific nature of regenerative agriculture, where no single measure or practice works across geographies or commodities, seems to be both one of the challenges and one of the primary reasons for taking a systemic approach. Now is a key moment for organisations across the food system to come together and explore the transformative potential of regenerative agriculture. To generate and scale up with urgency the solutions that can help bring regenerative agriculture into the mainstream, while maintaining its integrity and an ambition commensurate with the global challenges we face in our food system.
Farmers and land-owners may be on the front-line to implement regenerative agriculture, but they are part of a food system with complex and challenging power dynamics where responsibility and risk are often not shared fairly:
Understanding how systems change plays an important role in identifying the activities required to scale up regenerative agriculture. At Forum for the Future, taking a systems lens has helped us to identify some of the ‘building blocks’ that underpin a scaling-up strategy in regenerative agriculture. Interviewing organisations across the value chain has helped us identify some of the key barriers and interventions that we’re now exploring in projects.
We often witness pockets of excellence where various regenerative practices are being applied, but to scale and go mainstream, there’s a big journey ahead for this movement. Many farms and organisations will need to come together to drive this, each playing their own unique roles that will help support and scale-up regenerative agriculture.
Inextricably tied to this crashing of biodiversity is climate breakdown (one of several drivers of biodiversity loss) and in recent weeks, it’s provided some hope to see climate change having another spotlight in our media and politics. Thanks to the Extinction Rebellion and the #YouthStrike4Climate protest movements, increasing numbers of governments, cities and politicians are considering declaring a “climate emergency” and with that, there’s hope that these issues will be taken with the seriousness they deserve. It’s been energising to be a part of this.
Amongst all this excitement, I have been finding new hope in projects such as the wilding of Knepp Estate on 3,500 acres of degraded farmland in West Sussex. Since 2001, the land – once intensively farmed and highly degraded – has been devoted to a pioneering rewilding project that has seen extraordinary increases in wildlife, including extremely rare species like turtle doves, purple emperor butterflies and peregrine falcons.
The story of Knepp Estate is beautifully described by Isabella Tree in her book Wilding and the video below provides a good summary:
A few weeks ago I enjoyed a peaceful, inspiring weekend at Knepp Estate to see the experiment with my own eyes. We arrived on Saturday afternoon and after pitching our tent in their rather luxurious campsite, we enjoyed a walk across the northern section of the estate, through various habitats including lakes, meadows, woodland and messy scrub. We spotted various free-roaming grazers including Exmoor Ponies, Tamworth Pigs, Longhorn Cattle and Fallow Deer. Each providing a different force of natural disturbance that stimulates a complex mosaic of habitats for other species, as well as highly nutritious food for humans.The pigs, for example, rootle the landscape with their powerful snouts, overturning clods of turf which kickstart the creation of anthills (a great food source for woodpeckers) and provides good spots for solitary bees to settle. The exposed soil also allows pioneer plants like sallow to colonise (the food source of the purple emperor butterfly) and other plant species, increasing the complexity of the landscape.
I found it exciting to see the dense, messy, thorny scrub that Isabella Tree describes in her book. A giant playground for many birds and insects that are so often pushed to the edges of our environment. So much so, that for some species, observations at Knepp have been challenging our understanding about preferred habitats:
“We assume we know what is good for a species but we forget that our landscape is so changed, so desperately impoverished, we may be recording species not in its preferred habitat at all, but at the very limits of its range.” (Isabella Tree, Wilding)
As we finished our walk, darkness fell and almost all the birdsong had settled. All but for the call of a tawny owl and the famous song of nightingales which we were overjoyed to hear – a first for me.
At dawn the following morning, we joined a walking safari which guided us through a riot of bird song. On the walk, we spotted a yellowhammer, whitethroats, white storks, as well as hearing nightingales, cuckoos, chiff-chaffs and jackdaws.
The hope of rewilding
Despite growing up with keen bird-watching parents, the hobby never rubbed off on me. Only now am I starting to feel an interest, and with that, a greater curiosity in what we’ve lost and the efforts to conserve what remains. But with the startling facts about how much we have lost, “conserving what remains” is not enough. This is one of the attractions to Knepp and rewilding. It’s not a ‘conservation’ project in the traditional sense. It’s an open-ended experiment, using “process-led” rewilding principles such as grazing ecology to generate habitat complexity and biodiversity.
With no recollections of how the natural world used to be, it was striking to read Isabella Tree describing historical recollections of the abundance of wildlife in our landscapes – and the generational blindness to the environmental destruction that has been taking place. This tendency to normalise what surrounds us is known as ‘shifting baseline syndrome’:
…due to short life-spans and faulty memories, humans have a poor conception of how much of the natural world has been degraded by our actions, because our ‘baseline’ shifts with every generation, and sometimes even in an individual. In essence, what we see as pristine nature would be seen by our ancestors as hopelessly degraded, and what we see as degraded our children will view as ‘natural’. (Hance, 2009)
Rewilding presents a positive vision to help overcome a “shifting baseline syndrome”, by creating spaces that draw on an understanding of how our landscape once looked and how the ecology evolved. Now 20 years old, the Knepp experiment is deepening our understanding of ecology further and reminding of us of the severe negative consequences to wildlife from the intensification of agriculture and overgrazing of livestock in our national parks.
Hotly opposed by many farmers and conservationists, the gradual shift away from pasture-based farming systems towards intensive farming that accelerated after the Second World War, greatly increased yields but caused devastation to wildlife and is exhausting our soils. As we start to scramble desperately for solutions, Knepp shows one positive path forward for some of our most severely degraded landscapes. Not only for the sake of wildlife, but also for soil restoration, carbon sequestration, improving water quality and reducing flood risk.
With so many species hanging on for dear life at the fringes, we don’t have long to turn this around. Visiting Knepp gave me hope, inspiration and a heap of motivation to help rewild this planet. I highly recommend it for anyone else feeling a desire to take action.
Rewilding Britain: a charity that is working to demonstrate a model for rewilding that works at a scale new to Britain
This is the second of a three-part blog series on the Path to a Better Animal Feed System. In the last blog, I outlined why action on animal feed sustainability is urgent and gave a sense of the future direction for monogastric and ruminant feedstocks.
Improving existing feed sustainability, reducing demand and scaling novel ingredients are all solutions that promise to make feed more sustainable. This blog focuses on the action being taken by organisations on feed sustainability, providing examples of opportunities and barriers to change.
1. Where does current action focus?
While there is increasing interest in sustainable animal feed, action is limited and public pressure remains low. Our work is finding only a handful of major companies have feed-specific commitments. Buying policies and innovation are often patchy, inconsistent and lack the bold ambition that’s called for in responding to global sustainability challenges.
Most action from retailers and food service is centred around deforestation commitments and soy certification. Notable commitments include the Cerrado Manifesto and the Consumer Goods Forum commitment on zero net deforestation by 2020. The Cerrado Manifesto, launched in 2018 has had strong momentum, being signed by over 70 global companies. It puts the onus on soy and meat producers and traders, to prevent runaway destruction of the Cerrado savanna. However, without participation from major commodities firms such as Cargill, ADM and Bunge, there’s concern about how successful this initiative will be.
Soy is one of the most significant feed crops. Approximately one quarter of the animal feed market is soy-based, and 70-75 percent of global soybean production goes towards animal feed (Chatham House, 2016). Next to beef, soy is one of the leading drivers of deforestation. To encourage more responsible soy production, the Round Table for Responsible Soy is one forum seeking to develop and promote a sustainability standard for the production, processing, trading and use of soy.
Yet traction is limited. Certified ‘sustainable’ soy is increasing but still only 1-2 percent of the 270 million annual tons grown is certified sustainable. This compares to 21 percent of the global supply of palm oil.
Why is this? One factor is that there is limited public demand for sustainable soy, which remains a largely hidden ingredient in the supply chain. Another factor is financial. In 2018, one industry insider suggested that sustainable soy is less than 1 percent more expensive, however, the feed industry (who buy most of it) work on very thin margins and can’t absorb all the costs.
2. Other feed sustainability wins
While frustratingly slow, the focus on deforestation-free soy commitments is critical and requires strong collaboration and supportive policy. Alongside this, what other opportunities are there on sustainable animal feed?
For existing feedstocks, improving feed sustainability can include incorporating feed production into more regenerative agricultural systems, making better use of waste-streams and choosing ingredients that optimise the feed-to-food conversion efficiency.
In smaller-scale livestock systems, various examples exist where agroecological practices enable more sustainable feeding practice. We covered some examples in the first blog. Other examples include Joel Salatin’s Polyface Farm, where pastured poultry are part of a rotation requiring less grain-inputs and Kipster Farm in the Netherlands, where chickens feed on residual flows from bakeries and agriculture.
In larger systems however, there are fewer examples to draw from. In the UK, Waitrose has several initiatives on animal feed including efforts to source European soy, a collaborative Sustainable Forage Protein project and the trialling of alternatives to soy, such as locally grown fava beans for chicken, pigs, ducks and salmon.
Another example is Arla, one of the largest dairy farming co-operatives in Europe. It has collectively reduced CO2 emissions per kilo of milk by 24 per cent in Northern Europe, and optimising feed was a key part of achieving this. They now have targets to work towards net zero CO2 emissions by 2050 and to significantly reduce methane emissions.
It’s clear further action and incentives are needed. One of the biggest barriers often cited is financial: that sustainable or local feed production is more expensive. So organisations need to ask, what are the financial and policy incentives we can help create to help drive action and support a more even playing field?
3. Reducing Demand for Feed
Another strategy to address animal feed sustainability is reducing the demand for feed. In the previous blog, I discussed how the overall demand for feed might shift if human diets become more plant-based. Feed demand is also shifting as animal nutrition becomes more optimised or ‘precise’. This helps reduce pressure on land and resources, and could be an important opportunity to improve costs.
Studies at UC Davis led by Ermias Kebreab are showing how amino acid supplements can significantly reduce the imports of soybean, sometimes by over 50 percent in pig and poultry diets. The environmental impact is also considerably improved, with greenhouse gas emissions reduced by 56 percent and 54 percent in pigs and broilers. This demonstrates the potential for feed supplements to help improve the environmental footprint of feed.
4. Novel Feeds
Finally, there may be new opportunities to address sustainability with novel feeds. In our Feed Behind our Food report, we covered a number of novel feeds, including insects, algae and single cell proteins. These novel feeds continued to build in momentum in 2018.
In particular, we saw increased momentum for insects as feed, where the sustainability opportunity is their high efficiency in converting food waste or industry by-products into a high quality feed ingredient, with little land-use.
Several insect companies are currently scaling-up beyond demonstration plants, such as Ynsect(France) and Protix(Netherlands). In 2018, the Dutch retailer Albert Heijnlaunched a soy-free egg made from insect-fed layers (live insects are permitted). Protix also launched a ‘friendly salmon’ brand, in which the fishmeal content of the feed is replaced with their fly-larvae based feed.
As insect production starts to scale, will they reach cost-parity against mainstream feedstocks and offer nutritional advantages? Are there market incentives that will support this scale? These are outstanding questions. At present, the end-markets for insect-based feed are primarily pet food and aquaculture, because these are higher value markets but also because of regulation barriers. In Europe, the use of insects for feed has only been allowed since 2017 but is only limited to aquaculture.
While novel feeds are receiving increased coverage and investments, concerted and collaborative action are required to help support and accelerate their scaling. Particularly as there is limited demand from the public or value-added marketing opportunities currently.
We also need to understand how much of a step-change they can help deliver. Some companies we talk to are also feeling overwhelmed by the mindfield of novel feed companies coming to the market with different claims about the potential of their products.
5. The Power of Collaboration
What’s clear in our learning is that organisations acting alone cannot drive change across the system. Crucial to success is the power of collaboration. By working together, we stand a better chance.
Covered in Part 3 of this blog, I’ll explain how the Feed Compass collaboration aims to drive this concerted, collaborative action and help companies navigate the complexity. Looking holistically at the sustainability of these novel feedstocks, in relation to nutritional and financial outcomes.
For over a year I’ve been deep in the world of animal feed, working with companies in the food and feed industry and colleagues at Forum for the Future. In theFeed Compass project, we’ve been exploring the impacts of the animal feed system – and the strategies to make it more sustainable. It’s been a fascinating journey of discovery, surprise and complexity.
Now it’s time to take stock, share some of the learnings and potential pathways that can help shape a healthier, more sustainable animal feed system.
Part I: Why Pay Attention to Animal Feed?
How we feed and manage livestock matters. It matters because it relates to how we manage about half of the agricultural land on our planet, 80 percent of which is grasslands (Mottet, 2017). It matters because, in Europe alone, over 8 billion animals are raised annually – that’s more than there are humans on the planet.
Despite the media stories highlighting the growing interest in vegetarianism and veganism, meat production and consumption is set to continue increasing. Globally, we raise about 70 billion terrestrial animals per year, of which 50 billion are chickens. The phenomenal growth in chicken is notable, as is the increased appetite for pork in China and expansion of aquaculture across Asia. Figures 1-4 highlight some of these trends. Getting to grips with data such as this helps identify where the focus is needed, shining a light on the scale of the system and the shifting consumption patterns in different geographies.
Over recent decades, as farming systems have expanded and intensified, the world’s biodiversity has plunged. Global populations of fish, birds, mammals, and other vertebrates declined a staggering 58 percent between 1970 and 2012. The decline of insects is of particular grave concern. Recent research shows 40 percent of insect species are undergoing dramatic rates of decline. More than ever, land use needs to support biodiversity and increase carbon storage; livestock and feed production systems that support this goal must be prioritised.
Figure 1-4. Various charts highlighting the global growth of animal protein
a. Why feed requires special attention
As a farm, company or policymaker looking to increase the sustainability of the livestock sector, feed should be a top priority. It requires special attention for multiple reasons.
Feed nutrition has an important bearing on animal health and welfare, together with the quality of the end product. Feed is also a major cost in livestock production. For example, in pigs and poultry, feed typically represents about 50-60 percent of the total production costs. Finally, when examining the overall impacts of livestock production, feed is the component that contributes to the majority of land-use, freshwater consumption, chemical inputs and about half of the greenhouse gas emissions. This was highlighted in our Feed Behind our Food report in 2018 that helped build the case for retailers and foodservice to act.
Some have estimated that meeting future demands for animal protein with current feed sources could require 280 million hectares of additional land by 2030. To put that in perspective, that’s an area the combined size of Germany, Poland, UK, Ireland, France, Italy, Spain, Portugal, Belgium, the Netherlands, Switzerland, Austria, Czech Republic and Slovakia.
This land, if it were available, would also be in high competition for other uses, such as direct-food for humans, preserving or increasing wildlife, biomass production, carbon sequestration or water quality management.
In our seas, the future is also challenging. Today, nearly 85 percent of global fish stocks are either exploited or depleted – which itself contributes to climate change. Approximately 22 percent of wild fish capture goes towards animal feed, part of which is aquaculture, as well as poultry and pet food.
Despite the vast ecological footprint of animal feed, companies receive limited public pressure to take action on it. Most action that is relevant to feed, is around deforestation and the use of soy in the supply chain. This will be covered further in Part 2 of this blog.
b. Understanding future demands for feed
Over recent years, there’s been a surge of interest in eating less meat, particularly in Europe and the USA. The rationales for this trend differ but generally include animal welfare concerns, healthy eating and environmental concerns. Many food companies are responding by launching new plant-based product lines and menus.
Despite this trend, animal protein consumption is continuing to rise, albeit more slowly, and so the demand for feed continues to grow. Figure 6 shows that in 2018, an estimated 44 percent of global compound feed (non-foraged) went to poultry and 28 percent to pork. This highlights where some of the action to improve compound feed sustainability should focus.
While the future is difficult to predict, major disruption is inevitable. With climate change and soil erosion, biodiversity loss and resource pressures, there’s a fragility in the food system that demands urgent attention. Responding to these pressures and public health challenges, the recent Eat-Lancet Commission on Food, Planet, Health made a case for substantial shifts in global eating habits towards diets rich in plant-based foods and fewer animal-sourced foods. This comes off the back of countless other reports pointing in the same direction.
Figure 4 shows how the world population interacts with meat production with some future scenarios. However, to understand the future demand scenarios for animal feed, it’s necessary to get species-specific. With some dedicated resources, this would be possible to model.
c. Future directions for feed sustainability
Our work has identified three broad areas of focus for feed sustainability. Summarised below and in Figure 8:
Reduced demand for feed: by optimising animal feeding regimes and a shift in human diets towards “less and better” animal protein. Crucial to this shift is healthier human diets that include diverse plant-protein sources, grown in more regenerative or agroecological farming systems.
Scale-up of novel feed ingredients: that deliver improvements in land-use and greenhouse gas emissions. Such ingredients may include single cell proteins, algaes, insects and amino acids.
Improved sustainability of existing feedstocks: for example, deforestation-free ingredients, supply chains with improved transparency and traceability, feedstocks grown within more regenerative agricultural systems, feed ingredients that increase the feed-to-food conversion efficiency.
When exploring interventions and the direction of travel for feed sustainability, the discussion is complicated because of the vast differences across species and production systems.
Monogastric animals – such as poultry, pigs and fish – are more reliant on grains and pulses that compete for land that could grow human food. Ruminant animals – such as sheep, cattle and goats – rely more on grasses and forages that are inedible by humans. This is a simplistic but important differentiation.
The feed conversion ratio (FCR) is helpful to understand how efficiently animal feed is converted into food. While I’ve noted that feed for monogastrics can directly compete for land for food, Figure 9 shows that how these species are much more efficient converters of feed. However while useful, FCR is also imperfect when comparing between species. It is highly variable across farming systems and doesn’t take into account the nutritional quality of the end product, therefore misleading conclusions can be derived.
Monogastric farming Systems
The feeds fueling the rapid growth of monogastric livestock systems has been the expansion of intensively grown commodity crops such as corn and soy. This period of cropland expansion is beginning to slow and the feed industry faces increasing price volatility, complex trade dynamics and significant risks to future yields due to climate breakdown.
Much of the feed innovation today focuses on efficiency gains. For example, feed supplements such as amino acids can help optimise diets and reduce soy dependency. Integrating food-waste into feedstocks or scaling novel, less land-intensive ingredients such as insects, algae and single-cell proteins. Many opportunities exist, although it is not clear which (if any) are capable of providing a wholesale replacement for the mainstream feed crops used today.
Integrating more regenerative or agroecological practices into the cropland for monogastric feedstocks is another opportunity. These farming systems tend to be more diversified, so this shift will be more compatible with a future where humans have greater crop diversity in their diets, and “less and better” animal protein.
Figure 9. Contrasting two modern poultry systems: on the left, battery-cage layers. On the right, Kipster Farm (Netherlands), who aim to be most animal-friendly and environmentally-friendly poultry farm in the world.
Ruminant farming systems
Ruminants like beef get a bad stick. They have a poor feed conversion ratio, high water and land area requirements and have played a major role in driving deforestation (most newly-deforested land tends to be first put into beef production).
They also emit high rates of methane, a much more potent greenhouse gas than carbon dioxide but one that has a much shorter life in the atmosphere. This means their contribution to climate change over time is different from monogastric animals.
Ruminants have the advantage of being able to process protein inaccessible to humans. The impact of ruminant systems is highly variable depending on the practices adopted. Figure 11 contrasts two modern cattle systems. One is highly intensive, entirely reliant on external compound feeds that will include grains and pulses. The other is a low-intensity, grazing system, where feed is foraged from a managed landscape and the grazing is part of a system helping to restore degraded soil and increase biological diversity. Most farming systems sit somewhere in between, with varying feed management strategies.
In the more intensive ruminant systems, more reliant on compound feedstocks, there is some innovation on novel feed sources. Microbial proteins made from algae and yeast are showing promise in reducing cattle emissions. However, as with the novel feedstocks for monogastrics, these innovations do not appear to be wholesale feed replacements.
Figure 11. Contrasting cattle production systems: a) Calves live in hutches at Bengbu Farm in Anhui Province, China. With at least 36,000 cows, it’s the largest dairy operation in the country, helping meet the rapidly increasing dairy consumption. Image credit: National Geographic. b) grazing cattle at Knepp Estate, a free-range, low-intensity system that has radically increased soil carbon and biodiversity.
d. From diagnosis to action
What’s clear is that there’s huge scope for a feed system to support a healthier, more sustainable food system. The Feed Compass project is helping raise the importance of animal feed as a major sustainability challenge, where immediate action and investment is required. While we don’t have all the answers, there is a clear sense of direction emerging and scale of change that’s becoming clear. Through our work, we aim to help inform and shape pragmatic, intelligent responses to shape the feed system.
It’s also clear that delivering action on feed sustainability is impossible without a broader dialogue about how we provide nine billion people with enough protein in a way that is healthy, affordable and good for the planet. This is the central question of the broader Protein Challenge 2040 project.
This summer I’ve taken the opportunity to learn more about agroforestry. In August I spent a day at Wakelyns Agroforestry Farm in Suffolk with the UK Agroforestry Network, hearing from a variety of UK projects. Then in September, an agroforestry weekend course with Professor Martin Wolfe, hosted by Huxhams Cross Farm in Dartington.
Over the years I’ve become increasingly convinced of the important role agroforestry can play in helping our farming systems become more resilient to environmental pressures such as climate change. Therefore it’s been a pleasure to visit these sites, hearing first-hand the experiences from agroforestry experts. In this piece, I’m sharing some of the insights and learnings that stuck with me, as well as some resources.
First off, what is agroforestry? It’s the deliberate integration of trees and shrubs into crop or pastureland. This may be done for a variety of reasons. For example, providing shelterbelts for crops, valuable shade for animals, habitats to increase biodiversity, improvements to soil structure and health, and crop diversification. As such, agroforestry is not new. Humans have always been dependent on, or closely associated, with trees. Agroforestry practices stretch back thousands of years. You could even say that we evolved as agroforesters.
While many farmers are conscious of the value trees bring to their landscapes, industrial farming systems have created ever-increasing field-sizes, devoid of trees and shrubs, and dominated by single-variety mono-cultures. To provide reliable, predictable and cheap outputs, these systems are co-dependent on chemical inputs and large, expensive machinery. The result is cheap food. But at what cost?
The UK Environment Secretary, Michael Gove recently said that our soils have 30-40 harvests left. A fundamental destruction of soil fertility is underway. Alongside this, we’re witnessing other escalating environmental pressures such as climate change and an unprecedented loss of biodiversity, while being tasked with a quest for sustainable intensification as available land declines. So naturally, there’s increasing attention towards regenerative agricultural practices (methods of farming that increase ecosystem services, rather than deplete them) and in particular, agroforestry.
Professor Martin Wolfe and Wakelyns
It’s fitting to begin by introducing Professor Martin Wolfe, a pioneer of agroforestry in the UK. A plant pathologist by trade, Martin spent his early career as a scientist, particularly interested in the co-evolution of pests and wheat diseases. In 1984, while working at the Plant Breeding Institute in Cambridge, Martin was introduced to the term “agroforestry”. This was a key moment that started to shape his ideas and research. The idea of integrating the diversity of annual and perennial crops into a farm system led Martin and his wife Anne, to establish Wakelyns, a 22.5 hectare organic agroforestry system in 1994. The aim was to understand and compare different types of agroforestry systems. In particular, Martin has been fascinated with the diversity at every level of farming, from the soil microbia, to crop varieties and populations and the species of flora and fauna across the farm.
In agroforestry, there are some broad categories of systems:
riparian buffers: trees lining the edges of a watercourse: offering shade protection, as well as slowing down and filtering the water entering into the watercourse.
shelterbelts: usually wind protection. One of the largest examples of a shelterbelt is the Great Green Wall in China – still being planted, it is designed to protect from the dust storms of the Gobi Desert. It’s estimated to be completed in 2050, at which point it will be 2,800 miles long!
wood pasture: a mosaic habitat of trees, such as can be found in national parks.
silvopasture: combining trees and the grazing of animals in a mutually beneficial way.
parkland: such as you might find on estates.
forest gardens: designed to emulate natural woodland, very intensive, multi-layered planting of crops, typically small-scale.
alley cropping: described below:
At Wakelyns, the dominant approach is alley cropping whereby rows of trees are planted and a crop is grown in the alleyways between these rows. There is quite a different feel to a farm landscape that uses alley-cropping. It’s not possible to gaze across an expansive landscape. Instead, the feel is of intimacy. Secluded, quiet lanes that buzz with wildlife. The alley cropping system at Wakelyns, I understand, is the most mature in the UK.
The alleys at Wakelyns are orientated North-South, this is typical for minimizing shading in the crop lanes. Martin’s alleys are 12m width, which he selected to support a range of farm machinery (divisible by 3 or 4m). The tree rows are 3m wide. The site features three sets of tree system: a) hardwoods (e.g. ash, hornbeam, oak, hornbean), b) a hazel and willow coppiced system c) fruit and nut system.
The hazel is planted as a double hedge and coppiced alternately every five years, previously for weaving and thatch roofs and currently for on-site heating fuel. This rate of growth is considered fast – a standard coppice cycle is typically every seven years.
The willow is a five-component mixture of species, also planted as pairs, with 75cm between rows and 90cm spacing.
Land Equivalent Value (LER)
Some farmers may fear that trees compete for valuable space and water on a farm – thereby decreasing the yield of the primary crop. This is where the Land Equivalent Ratio (LER) becomes an important concept to help compare the yields of an agroforestry system that have multiple outputs (e.g. the yield from the tree crops such as fruit or timber) against a monoculture system.
The LER indicates the area of monocultures needed to produce as much as one intercropped hectare. Anything above one is a gain. So for example, if the LER is 1.4, the agroforestry system yields 40% more than if the crops are grown separately on two plots. How might this happen? There can be multiple reasons that support a positive interaction between trees and crops. For example, increased crop shelter (the trees help reduce wind speeds), improved soil and water quality protection, and reduced evaporation and water loss from crops. At Wakelyns, Martin has calculated an LER of 1.4 but he is mindful to note that there is nothing to accurately compare this against, as he doesn’t have a nearby monoculture of the same crop varieties grown under the same conditions. Martin believes that LER is helpful but we also need to develop Biodiversity, Carbon and Water Equivalent Ratios, helping understand better the other benefits happening in an agroforestry system. To this end, there is huge potential for further research.
One aspect of the visit that was particularly interesting was Martin’s work on Composite Cross Populations of wheat. Starting in 2001/02 and in partnership with the Organic Research Centre, an evolutionary breeding programme has produced a hugely diverse population of wheat suitable for organic and low-input farming systems. Known as “Population Wheat”, it was bred by making 190 crosses among 20 different parent varieties (some high yielding, and some highly resilient) and mixing all the resulting seed. This has now been through eleven generations of natural field selection, including at Wakelyns.
The diversity in the “populations” approach, both genetic and physical, means the crop has a better capacity to cope with a more variable climate, pests and diseases. This means that it’s also better suited for organic, low-input approaches. In a conventional monocultural system, identical varieties of the same crop are typically planted across a field. While this approach has convenience for marketing and manufacturers, the crop is less adaptable to environmental stresses. The Population Wheat demonstrates Martin’s pursuit for species diversity, not just at a macro-scale through alley-cropping, but within arable crop species.
A local food system
While many arable farmers have little control or knowledge of where their crop ends up, Martin has been able to link his farm products into a traceable local food system. This includes supplying into the award-winning Hodmedod’s – that specialise in beans and pulses from British farms (particularly focusing on less well-known and neglected crops) and Kimberley Bell’s Small Food Bakery in Nottingham. Both these enterprises have won BBC’s Food and Farming Awards in recent years. Establishing such a local food system is something Martin is passionate about and it demonstrates a replicable model for others.
Truly Traceable are also known to visit Martin’s farm – a rather unique enterprise that produces venison and game pies. Customers receive a certificate with their order, providing the location and a photo of the animal shortly after it’s been shot!
Huxham’s Cross Farm
The agroforestry course with Martin Wolfe took place at The Apricot Centre, Huxhams Cross Farm in Dartington. This is a 34 acre biodynamic, mixed farm that provides therapeutic support for families and children, as well as food production that includes the Population Wheat mentioned above, and mixed fruits, vegetables, and eggs, available through a local box scheme and markets.
This was my second visit to Huxham’s Cross this year and I’m incredibly impressed with how quickly this enterprise is transforming the land into a thriving, diverse and productive farm. It was only acquired in 2015 by the Biodynamic Land Trust and previously had been conventional barley for the last 40 years. An inspiring sign of how quickly landscapes and soils can start to be transformed. Not to mention, how farms can be designed as valuable places for people.
In terms of their application of agroforestry, vegetables are growing in an alley cropping system, with rows of hazel planted at 28m spacings. The hazel provides wind shelter, functional biodiversity and slows down the movement of water (and topsoil) down the field which slopes towards a brook. There’s a little more about the design process for the farm here, which was inspired by permaculture principles.
Broadlear’s Agroforestry Project
Just down the road is another new agroforestry project which Huxham’s Cross Farm is also involved with. What’s unique about this 48-acre field is the collaboration between multiple people and organisations: considered a “UK first” and therefore a valuable model to learn from. The different Parties include:
In terms of agroforestry approaches, forest gardening is the most intensive and diverse, often showcasing an enormous diversity of species. Because of this, forest gardens are typically more suited to smaller scale systems and are unlikely to be commercial operations. Martin’s two-acre forest garden was planted in 1994, interestingly, the same time Martin Wolfe was planting his trees at Wakelyns. As such, it’s a fantastic example of a mature forest garden. Each time I visit it’s like being in a wonderland of edible curiosities. Inspiring, peaceful and a place from which there is a lot to learn.
Martin also has two other sites where agroforestry is demonstrated at a different scale. An 11-acre site nearby in Littlehempston and a Fruit and Nut forest. On this occasion, we were also able to visit his Fruit and Nut forest, which is more of a commercial enterprise. Compared to his 2-acre site, the trees here are given wider spacings, allowing them to spread out and enabling much better access for harvesting. The way trees are planted is more like a parkland, but very well sheltered by strips of willow and hazel.
How might we scale agroforestry?
Agroforestry is becoming more recognised and growing in popularity. As the urgency of climate change intensifies and increasing calls for carbon drawdown unfold, there will be an increasing number of voices that call us to plant more trees, transform our landscapes and our agriculture systems. This is right. However, as it stands, integrating agroforestry into food production systems, as seen in alley cropping, remains a niche, counter-cultural idea. For many farmers, I suspect it feels a risky, uncertain and long-term investment. It’s easy to understand why. In the UK there aren’t enough examples of mature, productive farms thriving from their investment into agroforestry. For many conventional farmers, exploring agroforestry will require a shift in thinking about their approach to food production; moving from mono-cropping systems to a more complex, diverse system, besides an investment into new or different machinery.
When thinking about how agroforestry can scale, we need to take a hard look at the existing lock-ins of our industrial agricultural systems. IPES-FOOD’s Uniformity to Diversity report did a fantastic job at identifying these. For example, conventional farmers who have invested in large-scale, expensive machinery that lock them into industrial-scale cropping systems. Other lock-in examples might include farm business tenancies that don’t lend themselves to a patient, long-term investment into alley-cropping systems; or a policy environment that doesn’t support or understand farming agroforestry systems.
I like to think that all these challenges are surmountable. We urgently need many more agroforestry demonstration sites, knowledge sharing and support for farmers to test it. We should look globally at examples of best practice of where agroforestry is working in other countries. Examining the policies that will support it and the innovative ways in which farmers might integrate it – such as the multi-tiered tenancy approach at Broadlears. Right now in the UK, there’s a big opportunity with the new Agricultural Bill, to put in place measures to support agroforestry.
Agroforestry won’t happen automatically in response to environmental pressures. It needs advocating. Fortunately, we have some fantastic organisations promoting it (see the resources below) that need more support. Furthermore, we need to support the farming pioneers who are already practicing agroforestry. They have so much to teach us.
AFINET has been set up to share good practice, latest news and scientific achievements.
World Agroforestry Centre: based in Nairobi, a centre acts as a repository of agroforestry science and information, developing knowledge practices to ensure food security and environmental sustainability.
AGFORWARD: an EU four-year research project into agroforestry.
Agroforestry Research Trust: non-profit set up by Martin Crawford to research temperate agroforestry and all aspects of plant cropping and uses, with a focus on tree, shrub and perennial crops.
The Woodland Trust – UK charity, that can provide advisory support and free trees for farmers
Stephen Briggs’: a key practitioner and advocate of agroforestry in the UK. His system is based on 24m alleys, with a mix of perennials (apple trees) and annuals (cereals). He also runs Abacus Agriculture can provide advice on design.
On the horizon, a revolution in farming technologies promises to transform the ways in which we produce our food. This shift can dramatically reduce the volume of chemical inputs used and if we get it right, supports a transition towards a more regenerative approach to farming: one that builds healthier soils and increases biodiversity. The opportunity is enormous. With our food and farming systems facing unprecedented challenges ahead, what role do robots and precision farming play in the future?
There are many factors driving technological shifts in food and farming, from water and land availability to climate change and a collapse in biodiversity. I’ve written about some of these deep and complex challenges before. There are also many inefficiencies within existing farming practice to be addressed, such as the over-application of chemicals and soil erosion. These challenges are inspiring a wave of new technology start-ups, aiming to offer solutions to some of these deeply complex problems.
This piece covers some of the themes in emerging agricultural technologies. My motivation is to make better sense of what these might mean for farmers, citizens and our ecosystems.
Autonomous, ultra-light machines for crop care
A few months ago, I spoke with Professor Simon Blackmore who heads up the Robotic Agriculture department at Harper Adams University. Here they focus on precision farming and robotics and no doubt have a lot of fun building them! In 2017, they famously achieved a “hands-free hectare” where everything from ground preparation and drilling, to plant care and harvesting was completed without a human stepping onto the land.
Professor Blackmore’s view is that while the past trend in farm machinery has been based on economies of scale with tractors getting bigger and bigger, the future will be about smaller, more nimble machines. These machines will operate autonomously, moving intelligently around the crops. They will be ultra-light to avoid soil damage and enable a major reduction in the application of chemicals.
What struck me in his work is the amount of reduction that can be achieved. The video below demonstrates a sensor that can intelligently recognise different species of plants and either zap them with a laser for weed control or apply a micro-droplet of chemical to a leaf, achieving a 99.99% reduction in the volume of herbicides. Currently, the majority of chemicals coming out of a boom sprayer are missing their target altogether (with around <5% efficiency).
This is impressive and the technology isn’t just conceptual. Already, several companies are offering solutions in this space: Blue River Technology (USA) is developing robots that use computer vision to “see and spray” at weeds. Deepfield Robotics (Germany) have a robot which stamps weeds into the ground as an alternative to using herbicides. Ecorobotix (Switzerland) have an ultra-light, solar-powered autonomous weeder. Naio Technologies (France) have various bots for weeding, as do the Small Robot Company (UK). Rootwave (UK) are pioneering electrical weeding robots. The technology is already available for those willing to pay.
What does this mean for farmers? A few things. Farmers purchasing far fewer chemicals and spending less time going up and down their fields. Tractors able to work around-the-clock, autonomously and meticulously over the crops. I don’t believe this technology designs farmers out of a job, it will just shift how they spend their time.
This is an example of robotics performing crop care. For managing land, there are generally three other categories of agricultural robotics: scouting (e.g. collecting data on soil, plant and other environmental conditions), drilling (planting out) and harvesting. Let’s explore some of the others.
Scouting, monitoring and analytics
Farming is becoming increasingly digitised, enabling practices to be more reactive to local conditions such as weather, soil characteristics and micro-climates. Satellite monitoring, drone-captured imagery and remote sensing are enabling collection of pinpoint field-based ‘nearly-live’ data. The software then provides farmers with bespoke prescriptions to help work each field, down to a fraction of an acre.
While it’s still early days in their development, many farmers are already adopting precision technologies. Many companies, such as Soyl provide field mapping services enabling farmers to apply variable rate application of fertiliser.
There’s a huge wave of startups in this space and a frenzy of acquisitions are taking place, mostly for the services aimed at the larger, industrial farms. This is creating market consolidation rather like that seen in silicon valley with the likes of Google, Facebook and Amazon. Farm data is expected to be a $20–$25 billion revenue opportunity and so every agribusiness is adding data services into their offerings. Here are some examples:
Teralytic builds wireless sensors that detect 26 different parameters of soil health, giving farmers a detailed map of soil conditions across their farm.
Farmer’s Edge is a hardware and software product that uses satellite imagery and precision technology to help growers identify, map and manage farmland variability. To date, the start-up has raised $94.3 million in funding.
For integrated pest management, examples include Semios and AgroPestAlert who offer networks of camera-traps, providing farmers with automated pest counts and notifications.
McCain Foods recently invested in Resson, which uses near real-time predictive analysis for crop management.
Farmobile enables farmers to collect and then sell their field data to third party’s.
What does this mean for farms? Ultimately, it’s about optimising resources, building better soil health and achieving better yields. Some of the current challenges include data interpretation, dealing with multiple, disconnected data sources and an inability to connect data to agricultural machinery. There are also issues around data ownership, transparency and trust in the large companies that use the data, leading to responses such as the Ag Data Transparency Evaluator in the USA.
For many crops, harvesting has long been a mechanised process and this trend continues across the world. However, for the more delicate crops, hand-picking is still dominant.
It’s taken Boston Dynamics 26 years to build a robot that can open a door. As I write, even the most advanced robots are still bulky and struggling with delicate movements, but we know this will change. In some countries, this is being driven by labour shortages, where local people are unwilling to take on the intensive, poorly-paid harvesting jobs.
Last year the startup, Abundant Robotics raised $10M from investors including Google Ventures and Yamaha Motor Ventures to develop apple-picking robots. Octinion is developing a strawberry-picking robot. While not a harvesting robot, Augean Robotics have developed a neat autonomous, rugged cart robot that can follow a person around and haul things for them. Other companies include Harvest Automation, Kespry, Lely and the Autonomous Tractor company.
One of the possible benefits of harvesting robots is selective harvesting to reduce food waste: with robots programmed to assess the quality and quantity of harvestable produce, only harvesting what is sellable. Other than that, these advances are about saving costs, with questionable benefits for labour. Pessimists see these advances as bad for jobs. While advocates believe robots can eliminate the worst jobs, while increasing food production, maintaining food costs and reducing the environmental impacts of farming.
Scale-up and commercialisation
There’s an interesting question about how quickly these different technologies will come to market as affordable propositions – and when they do, for whom will they be available?
Taking a general look at technology, we can see that it has been distributing itself more and more rapidly. For example, it took 46 years for electricity to mainstream and only 7 for the world wide web to do so. What’s supporting the pace of agricultural tech development is the rapid advances being made in artificial intelligence, data analytics, robotics and sensors: all of which are converging to provide a suite of new tools.
However, the rate of technology adoption is not just governed by its availability. When it comes to big pieces of equipment, traditionally, farmers make large investments that take many years to pay off. As such, they can be locked into equipment and their associated practices. This lock-in can mean farmers are slow to change and wary of investing in new systems, especially ones that dramatically shift their practice.
These new technologies may not follow this trend though. Water constraints and a push towards sustainable intensification will drive uptake of new technologies and incentives for their uptake. We are also talking about smaller pieces of kit, many of which are suitable for smaller farms, not just large, industrial farmers. There’s also changing business models for products too, with some companies offering products on a per-hectare subscription rather than one-off investment.
Designing for regenerative farming
How these new technologies support regenerative farming should be a central question for designers. Regenerative agriculture describes farming and grazing practices that, among other benefits, rebuild soil organic matter and restore degraded soil biodiversity – with the aims of carbon sequestration and improving the water cycle. These technologies can support regenerative farming in a number of ways, for example:
Ultra-light tractors can help eliminate soil compaction problems;
The precision application of chemicals can help reduce soil damage and pollution of watercourses;
Many of the robots can work to a 2cm accuracy (using RTK navigation) meaning that every seed can be placed precisely and mapped. This can support multi-cropping practices that can aid natural pest control and improve biodiversity and yields.
Scouting and crop care technologies can help optimise irrigation, increasing water efficiency.
Designers should also consider that the majority of farms worldwide are small-scale and the importance this has for food security, local economies, livelihoods and biodiversity. So how can these technologies be made affordable and accessible for small-scale producers as well as the large ones? And finally, how can these technologies assist farmers to make better, more informed decisions?
It’s an exciting time for farm technologies. Let’s hope they scale to reach their full potential, as technologies guiding us towards healthier, more resilient food systems.
This is an essay about sustainable intensification, a goal in farming whereby yields are increased without causing harm to the environment or cultivating more land. It’s one of many approaches that will help secure food for our future generations.
The essay explores its potential role and is divided into three parts. Part 1 provides some context, examining the complex, deeply interconnected and mutually reinforcing problems in our food system. Part 2 introduces the underlying concepts of sustainable intensification and its contribution to help address challenges in the food system. Part 3 critiques different approaches to food production, comparing the potential roles of industrial agriculture against diversified agroecological approaches.
This is an adapted version of an essay I wrote for a Food Security course I’ve been doing with Bangor University. Therefore it’s a little more formal and academic in style than my usual posts.
Part 1: Historical Context and Food System Challenges
In 1943 during the midst of World War II, a seminal event for the future of food and agriculture took place in Hot Springs, Virginia. Representatives of the United Nations gathered together for a conference comprising of 44 governments, representing 75 per cent of the world population. Their ambitious task was to reach agreement on certain plans for the production, distribution, transport and consumption of food across the world after the war (Lyon 1943). The delegates included diplomats, politicians, as well as experts in nutrition, economics and agriculture. The conclusion was that freedom from want of food, suitable and adequate for the health and strength of all peoples, can be achieved (FAO 1981).
During this period, substantial changes in agricultural practice were starting to spread across the world. Beginning in the 1940s and expanding significantly in the late 1960s, the ‘green revolution’ included new farm management practices, higher-yielding varieties of plants, synthetic fertilisers and pesticides, all of which contributed to increased yields. Worldwide, gross crop production grew from 1.84 billion tonnes in 1961 to 4.38 billion tonnes in 2007, an increase of 138% (Royal Society 2009). During this same period, global land for agriculture increased only 10%, from 4.46 billion ha to 4.92 billion ha (FAOSTAT 2016). While a huge achievement for increased yields, this intensification has been responsible for significant ecological degradation including water, air and soil pollution, causing sharp declines in biodiversity, increased greenhouse gas emissions contributing to climate change, and depletion of non-renewable resources (Foresight 2011; WWF 2016).
The increases in yield supported another substantial trend during the 20th century. Aided by advances in healthcare, the human population grew from 1.7 billion in 1900 to 7.3 billion in 2015 (UN 1999; UN 2015). It’s expected that population will level out at 8-10 billion by 2050 with the highest rate of growth expected in Africa (UN 2015).
Increased food demand is one of many pressures facing humanity today. While there’s been positive developments in the last 50 years such as a decline in the proportion of people suffering from hunger (FAO 2015), many major problems exist in the food supply chain:
Many systems of food production are unsustainable, degrading the environment and compromising our future capacity to produce food (Foresight 2011): modern agriculture is causing problems such as overfishing, soil erosion, loss of soil fertility, salination, eutrophication and rates of water extraction exceeding replenishment. These practices are also contributing to climate change and biodiversity loss.
Widespread hunger: an estimated 795 million people remain undernourished (FAO 2015).
Over-consumption: over one billion people are substantially over-consuming, resulting in a public health epidemic of chronic health conditions such as cardiovascular disease and type-2 diabetes (Haslam 2005).
One significance of the 1943 Hot Springs Conference was that it laid foundations for the Food and Agricultural Organisation (FAO), an organisation dedicated to overcoming food and agricultural challenges through multilateral collaboration of governments and organisations. To respond to challenges in the food system, FAO developed the concept of food security, as defined below, which lies at the heart of its efforts today:
Food security exists when all people, at all times, have physical and economic access to sufficient safe and nutritious food that meets their dietary needs and food preferences for an active and healthy life. — 1996 World Food Summit (FAO 1996)
The evidence that substantial changes are required throughout the food system to meet food security and sustainability goals is overwhelming (Foresight 2011; IPES-Food 2016). These changes must be achieved from within a deeply complex food system comprised of a mostly self-organised set of interacting parts. Figure 1 provides a representation of the food system showing relationships between key drivers, activities and outcomes.
Figure 1 shows that food system activities determine various outcomes, including levels of food security and social and environmental welfare. The environmental challenge includes respecting and operating safely within planetary thresholds1 that safeguard our future by protecting ecosystem services. The social welfare challenge includes a variety of issues such as income, jobs, health, energy and food.
One approach developed by Oxfam to frame humanity’s challenge is the ‘doughnut of social and planetary boundaries’, shown in Figure 2 (Oxfam 2012). This communicates a vision of prosperity that involves living within the ecological means of the planet while ensuring everyone has the resources required to meet their human rights. We need to design our food system to operate in this space and just space.
Part 2: Key Concepts in Sustainable Intensification
2.1. Definition and context
Sustainable intensification is a relatively new term that has been interpreted differently by different people (Garnett and Godfray 2012). The Royal Society (2009) defined sustainable intensification as a goal for agricultural production wherein “yields are increased without adverse environmental impact and without the cultivation of more land”. This definition frames sustainable intensification as an aspiration for raising productivity, not privileging or articulating any particular type of production (Garnett and Godfray 2012).
Sustainable intensification has been considered one component of action on a variety of fronts to achieve food security and sustainability goals, as shown in Figure 3 (Garnett and Godfray 2012). While this essay focuses on sustainable intensification, it’s recognised that action is required across multiple fronts to meet these goals.
2.2. An increasing demand for food?
As described in Part 1, a wave of agricultural intensification occurred during the 1960s. However in recent decades there has been increasing yield stagnation in the world’s major cereal crops (FAO 2002; Ray 2012). Studies project an increase in global food demand until 2050 and an increasing share of animal-based products in people’s diets, especially in rapidly industrialising countries such as China (Bodirsky 2015). These changing dietary preferences are influenced by multiple factors including income, climate, urbanisation, food prices and markets (Drewnowski 1997; Bodirsky 2015).
Studies forecasting future crop production demands fluctuate significantly. For example, the FAO has projected a need for a 60% increase by 2050 (FAO 2013) while a study by Tilman et al. (2011) suggested a 110% increase was required. While increased demand is probable, it is worthwhile recognising the influence of dietary preferences and inefficiencies. Figure 4 estimates the total food calories potentially available for human consumption if waste and the inefficiencies of animal production were removed. This highlights opportunities in demand management and food waste reduction. Lundqvist et al (2008) estimate that global food production is already theoretically sufficient to feed the planet twice.
2.3. Ecosystem services
Humans derive a range of benefits from ecosystems, without which we would not survive. One approach that helps recognise these benefits is known as “ecosystem services”. Figure 5 gives examples of these across a range of habitats, taken from the UK National Ecosystem Assessment (UNEP-WCMC, 2011). Ecosystem service assessments show how provisioning services such as food are just one of many benefits we derive from farmlands, making it a useful concept to draw from when we talk about sustainable intensification.
2.4. Land sparing and land sharing
Future food demands can be met by expanding the area of agricultural land available or increasing yields through intensification on existing farmland. Throughout history, increasing tracts of land have become managed by humans (Figure 6). Approximately 40% of land cover is now given to crops and pasture (Foley 2005) and there are recognised limits governing continued expansion of agricultural land:
Remaining land usable for agriculture consists mainly of forests, wetlands or grasslands (Garnett 2013). Most of the highest quality land is already used for agriculture and much of the remaining areas are less suitable (Tilman 2002).
Land conversion reduces rates of carbon sequestration, impacting climate regulation and other ecosystem services; rainforest clearance is a prominent example of this. Climate change is already affecting yields (Lobell 2007) and further climate change will particularly impact lower-income countries (IPCC 2014).
Unsustainable biodiversity loss reduces our future capability to produce food (Scherr 2012). 35% of crops depend on pollination and the global decline in pollinators is driven by the use of pesticides and habitat loss from intensive agriculture (IPES-Food 2016).
Competition for other land use such as built environment, culture and recreation.
Freshwater availability and competition for water limits agricultural production. 70% of freshwater withdrawals are used in agriculture, mostly for irrigation (WRI 2005). Unsustainable water consumption has led to draining of aquifers and reductions in river flows. Currently, water stress affects more than 2 billion people around the world and this figure is set to rise (UN 2016b).
The choice between intensification or expansion of agricultural land is sometimes framed as a discourse in comparing two land management approaches, known as land sparing and land sharing:.
The idea behind a land sparing approach is to focus highly intensive agriculture on one piece of land, while ensuring there is associated land set aside for conservation.
In a land sharing strategy, less land is set aside specifically for conservation, but less intensive production techniques are used to maintain biodiversity throughout agricultural land.
While this dichotomy offers a heuristic for thinking about trade-offs, it’s important to recognise that these strategies are not mutually exclusive and in reality, there are options in between. For example, farms can combine elements of land sparing and wildlife-friendly farming. Three challenges for land sparing are: 1) ensuring long-term food production is viable on the intensively managed land, 2) managing spillover, off-site negative effects such as
Three challenges for land sparing are: 1) ensuring long-term food production is viable on the intensively managed land, 2) managing spillover, off-site negative effects such as such as impacts from the production of agro-chemicals or water pollution and 3) land spared not being adequately tended to maximise ecosystem functions or have long-term protection assured (Fischer 2014). Fischer et al. (2014) identified how the discourse of land sharing vs sparing lends itself to polarisation and various frictions in the scientific community, recommending that an alternative, more holistic analytical framework may support better analysis.
2.5 Measuring what matters
In securing a long-term food supply, a common question when evaluating sustainable intensification concerns productivity. As an example, the question “can an organic farm be as productive as a non-organic farm?” is fraught with difficulties in measurement, such as:
Which units of measurement? It is common for farm productivity to be measured as the production output against the land area (e.g. tonnes/hectare), production output against labour input, or the financial value of the output. Although useful, each measure offers a narrow view of productivity, not accounting for aspects such as the efficiency of inputs used in the production such as water, chemicals and energy. Measuring the “sustainability” with regard to productivity might also call for units such as “output per unit of water” or the carbon footprint (output per kg CO2e).
Some inputs may be produced off-site, for example, the animal feed. Therefore measuring or comparing the efficiency of production becomes difficult without conducting detailed life-cycle assessments.
Measuring multi-crop productivity: for example, some farms might practice intercropping with the aim of increasing total productivity. This is common in agroecological approaches to farming and makes comparisons against monoculture productivity difficult.
Measuring ecosystem services beyond food provision: farms often provide a range of ecosystem services (see section 2.3) that are not explicitly valued financially.
Other conditions affecting productivity: every farm will have its own climatic conditions (e.g. soil, weather, slope, water) that will greatly influence productivity. Therefore the question of productivity between two farms must take into account their site conditions. Only carefully conducted trials or aggregating data across a sector makes it possible to compare productivity across different types of agriculture.
These complexities in measurement explain why there is a limited evidence base and lively debate regarding the potential for different modes of agriculture to “feed the world”. The next section explores this in more detail.
Part 3: Approaches to food production
Adapted from IPES-Food (2016), Table 1 contrasts two ends of a spectrum for approaches to agriculture. While both share a goal of food provision, specialised intensive agriculture tends to focus on achieving a maximum volume of product, whereas diversified agroecological approaches tend to aim for multiple yields with less external inputs. There are of course, many farmers that operate in the middle, adopting practices from both approaches.
Figure 8 lists agricultural system outcomes that can be evaluated when comparing trade-offs between different modes of agriculture. While each outcome is important, it is not possible in this essay to provide a comprehensive critique of all outcomes. To explore the form of sustainable intensification, the following section focuses mostly on productivity and environmental outcomes.
3.1 Industrial agriculture
3.1.1 Productivity: Yields
Despite recent decades of yield growth stagnation (described in section 3.2), agri-tech firms suggest significant increases are still possible from a combination of biotechnology, advanced plant breeding and improved farm-management practices. Advances include genetic modification, resource efficiency through precision farming and improved herbicides and pesticides. One multinational company, Monsanto, has a goal to double yields of corn, soybeans and cotton between 2000 and 2030 using these techniques (Monsanto 2016).
Elsewhere, there is concern that focusing on maximising yields comes at the expense of future productivity as ecosystem services become degraded even further (Deguines 2014; Tilman 2002). Similar doubts are shared for the livestock sector which will be increasingly affected by competition for land, water, food and feed, as well as a low-carbon economy (Thornton 2010).
While firms focusing on the industrial model of farming publicise impressive yield targets, maintaining its character presents some serious environmental risks such as:
Loss of ecosystem services: farms provide a diverse set of ecosystem services, some of which are degraded by industrial practices. For example, removal of trees increase the risk of flooding, soil erosion and reduce biodiversity. The worldwide loss of pollinators is another example, closely linked with industrial farming practices and threatens future food production (Clermont 2015).
Resilience and vulnerability: monocultures of genetically uniform species creates erosion of the gene pool, posing greater vulnerability in crop disease outbreaks. For example, of the 7,616 livestock breeds that exist, about 86% are local breeds present in one country and 20% of these are at risk of extinction (IPES-FOOD 2016). With the unpredictability of future stresses, the implications of genetic erosion could be huge. The reliance on pesticides also binds farmers financially to agri-tech companies, and weed resistance to pesticides fails to address underlying problems of pest resistance (IPES-FOOD 2016).
Land degradation and soil erosion: intensive industrial agriculture has been considered the largest contributor to land degradation at a current rate of 12 million hectares per year (ELD Initiative 2015).
Water contamination: chemical inputs result in particularly high risks of runoff leading to contamination of water courses (Boardman 2003). Furthermore, current trends estimate that 50% of irrigated arable land will be salinised by 2050 (Jamil 2011).
3.2 Diversified agroecological farming
3.2.1 Productivity: Yields
Long-term studies comparing yields between agroecological systems and industrial agriculture are limited (IPES-FOOD 2016) due to complexities such as comparing monocultural yields against polyculture yields, and comparing different farm types and sizes (see section 2.5). Studies that exist mostly focus on organic farming (described below) and tend to record lower yields when compared to industrial monocultures in developed countries, but higher yields in developing countries and on smaller farms (Kirchmann 2008):
Badgley et al. (2007) analysed 293 yield comparisons between organic (or semi-organic) and industrial production and found that organic systems produced 8% lower yields than conventional in developed countries, while in developing countries, organic systems outperformed conventional approaches by far.
De Ponti et al. (2012) analysed 362 paired sets of yield data across 43 countries, reporting organic yields as 80% of those obtained under industrial.
Pettey et al. (2006) examined 286 interventions in developing countries and found that farmers adopting agroecological practices had an average of a 79% increase in yields (Pretty 2006). This was against a variety of baseline agricultural approaches.
When comparing the productivity of polycultures, several studies demonstrate that “less land is required to produce in polycultures than to produce the same amount in monocultures, making yield per area higher in polycultures” (IPES-FOOD 2016).
Organic farming operates without pesticides, herbicides, antibiotics or inorganic fertilizers. It’s the most well known form of agroecological farming and various certification schemes exist for accreditation of organic practice. Organic practice involves elements such as crop rotations and diversification to maintain yields and manage pests. Factors limiting yields can include lower nutrient availability and weed control.
While the share of agricultural land being managed organically is increasing, globally it accounts for just 1% (FiBL 2016). The potential scope for organic farming is disputed. Some assessments have concluded that global food provision could be met by upscaling organic agriculture globally (Bagdley 2007) while critics believe that the amount of nitrogen fixation required to achieve necessary yields cannot be met sufficiently by animal and green manures (Halberg 2015; Kirchmann 2008).
Exploring the same environmental outcomes used in section 3.1.2, diversified agroecological approaches offer the potential to help achieve sustainability goals and longer term resilience:
Ecosystem function and services: organic farms host greater biodiversity than industrial systems and this contributes to the delivery of ecosystem services. A meta-analysis found organic farms to have an average of 30% higher species richness than industrial systems, and 50% more species abundance (Bengtsson 2005).
Resilience and vulnerability: agroecological farms tend to operate at smaller-scale with greater crop and livestock diversity. Practising year-round production and greater crop diversity can create a more resilient food supply during seasonal shortages (Powell 2015), environmental stresses and extreme weather events (IPCC 2014).
Land degradation and soil erosion: the focus on building soil organic matter so that crops have the nutrients required supports better water-holding capacity and carbon sequestration.
Water contamination: instances of water contamination are reduced as a result of less chemical inputs.
To secure a long-term sustainable food supply, sustainable intensification must occur within safe operating boundaries to preserve and enhance ecosystems (Figure 2). The required ‘intensity’ of production hinges on success across several fronts such as demand management, reducing waste, lower-impact diets and improved farming practice (Figure 3).
Even while promising improved yields with approaches such as biotechnology and GM, the analysis in section 4.1.2. suggests that by maintaining its character, the industrial model will continue to degrade numerous ecosystem services. This is a dangerous tract, threatening long-term human survival.
Agroecological approaches offer significant potential for addressing sustainability goals including resilience. Yield comparisons can be comparable but vary significantly and evidence on capacity for increased yields is limited and disputed. For approaches such as organic farming, studies suggest there are significant productivity gains possible in developing countries. Yield improvements may occur through better knowledge-sharing, precision technologies and increased intercropping (Halberg 2015).
The natural question is whether there is scope for convergence. As shown in Figure 8, can industrial agriculture integrate agroecological practices while continuing to intensify? Some form of convergence seems imperative to meet sustainability goals. In its form, the convergence needs to be transformational. Several reports suggest that just “tweaking practices” in industrial agriculture is not enough and won’t deliver the change required to respond properly to sustainability challenges (Foresight, 2011; IPES-FOOD 2016).
Transforming the industrial agricultural sector is challenged by “lock-ins” that act as barriers to change. For example, industrial agriculture often requires significant financial investment (e.g. machinery for monoculture production) and once that investment has been made, it is difficult for a farmer to change course. IPES-FOOD (2016) have identified eight “lock-ins” and solutions that could help unlock industrial agriculture to become more agroecological, as shown in Figure 9. This shows the important role of governance, food policy and further research to help realise sustainable intensification.
Sustainable intensification is one of several paths that will improve resilience and efficiency in the food system. The degraded state of ecosystems and the sense that “time is running out” to effectively mitigate climate change impacts demand urgency in response. Industrial agriculture is challenged with maintaining yields while diversifying and significantly reducing its inputs and widespread environmental impacts; “tweaking” practices is not enough. While diversified agroecological modes of production must be scaled-up with further innovation to improve yields. A convergence of thinking is needed however several “lock-ins” for industrial agriculture extending beyond food production make this transition difficult, highlighting the role of further research, improved governance and policy.
This essay provides an overview of key issues for sustainable intensification and is not a comprehensive assessment. Many important agricultural outcomes such as livelihood, income, and employment conditions were not discussed. Further reading is encouraged by exploring the references used in this essay.
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