A way forward

The climate change talks in Dubai are once again compromised by vested interests countering proposals to secure a sustainable future for our planet and its residents. That is shocking, only because of the existential global ramifications of a failure to implement those proposals.

We all have vested interests. Sometimes they can be a driver for good. There are some opportunities to be realised through adoption of climate change mitigation and adaptation strategies, but we need to accept that there are sacrifices too, and individuals vary in their willingness to embrace this for the greater good.

In the final chapter of Farming with the Environment, I explore related issues from an agri-environmental perspective. We know from our own experience at and around the Allerton Project’s own farm that farmers are suffering the consequences of climate change through summer drought, winter storms and waterlogged soils. As well as reducing national food production, there are substantial implications for farm businesses.

Farmers recognise the need to adapt to a changing climate to stay in business, but additional to this is the need to contribute to mitigation of global climate change, and to adaptation measures that have societal benefits beyond the farm boundary. The trade-offs between climate change adaptation and mitigation, and between private and public benefits are complicated, but we need to understand them in order to encourage and fund the appropriate necessary action. The mechanisms for paying farmers for these multiple activities are evolving but are still very uncertain.

Nature recovery is a key part of this equation, including life in water, and on and in the land. In developing plans for future land management we need to consider the trade-offs and synergies between our multiple demands on agricultural land. We all have different perspectives on this, depending on our personal values, cultural and economic circumstances, and where we happen to live, but ultimately, locally and globally, we are all dependent on the health of the same environment. There is no escaping the physics of climate change.

Over the past thirty years, Allerton Project research has made a valuable contribution to understanding these complicated but fundamentally important issues. There’s still a long way to go, but we have laid down some foundations, not just for future research, but for national policy, and practical management on farm.

The View from the Farm

Farmers are experiencing a period of considerable change as area payments are withdrawn, global market pressures reduce income, climate change introduces unfamiliar challenges, and new agri-environment schemes are rolled out. Chapter 8 of Farming with the Environment explores these issues from the farmer’s viewpoint, based on our collaborative working with local farmers on various initiatives over the years.

Global markets determine prices received by farmers and shocks such as Russia’s invasion of Ukraine, or climate change related impacts influence both commodity prices and input costs, independently of anything farmers can do to control them. Importation of food produced to lower environmental or welfare standards than in the UK, and sold at lower prices, represents a major challenge for the viability of farm businesses, and for environmental standards across the world.

Climate change increasingly also affects yields. Within one decade, we experienced two years in which wheat production was reduced by 40% as a result of excessively wet autumns for example. Droughts also take their toll.

With the loss of area payments following the UK’s departure from the EU, farmers will be increasingly reliant on Environmental Land Management scheme payments, but these are designed to cover only income forgone and management costs.

Some of the management practices supported by the Environmental Land Management scheme can contribute to food production but our work with other research partners shows that the extent to which this applies varies considerably between farms. Economic data from local farms also shows how farms differ in the profitability of arable crops, with for example no relationship between the level of inputs and profitability. This might be due to astute business management or agricultural expertise on the part of some farmers, but might equally be a result of variability in farm infrastructure, size, tenure, soil type, topography etc.

Our social science research reveals how farmers learn through their participation in agri-environment schemes, and while this process is not always linear, it can result in a strengthened sense of identity with wildlife conservation and broader environmental issues, and ultimately to leaders who inspire others and encourage management at the landscape scale. We have also documented evidence that those who participate in agri-environment schemes adopt additional practices that contribute to sustainability.

There is growing awareness across the farming community of the need to improve the management of farmland, both to meet environmental objectives and to ensure the future productivity of the land to maintain food security. This can only be achieved if there is sufficient economic support to meet these societal objectives. Some of the issues associated with this are explored further in Chapter 9.

Understanding and accepting complexity

Politicising climate change is dangerous. There are numerous examples of how forcing complex environmental issues into binary choices doesn’t turn out well. Understanding the science, accepting the complexity, and acting on the best evidence available at the time is the only way out of the considerable challenges we currently face.

In chapter 7 of Farming with the Environment, I use a very specific example from our research at the Allerton Project to illustrate this. At one time, there were polarised views about whether restoring songbird populations could best be achieved by improving habitat or reducing predation pressure. Our intensive research demonstrated that the answer varied between species, but with both being important considerations to varying degrees.

There were interactions too. Habitat structure at the nest site influenced nest predation rates, and habitat at the scale of songbird breeding territories also had an impact. At the landscape scale, habitat heterogeneity influenced the size and composition of the predator community. And for those species which migrate, conditions in West African wintering areas were important considerations – the chapter contains the evidence base for that too.

There’s also a discussion about rewilding, a popular but much abused term, and the polarisation between farming and forestry. Our research provides examples of how integrating trees into livestock farming helps with mineral supplementation, intestinal worm control, and reducing greenhouse gas emissions.

And then there’s dichotomy between agricultural and domestic contributions of phosphorus to our streams and rivers. Of course it is both, but the relative contribution of each varies with catchment and scale. We are central to this as individuals, whether by buying food or flushing toilets. But water companies and national policies are falling short of what is required.

Yes, it is complicated. That is why the research is so important. And whether as individuals, businesses or policy makers, we need to act on that evidence and not on short term expediency.

Reflections on water

Chapter 6 of Farming with the Environment covers the aquatic side of things. Some of it is about how nutrients behave in water and how aquatic invertebrate communities are affected by them. But the fact is that what goes on in water is influenced massively by the management of the land draining into it.

Our research over the years has improved our understanding of sediment movement to and within water, and the strong association with phosphorus in particular. We have shown how invertebrate species diversity is negatively affected by phosphorus concentrations and how the fine particles associated with our clay soils are held in suspension and provide the main mechanism for phosphorus transport from agricultural land to water. Chapter 3 of the book covers this from a soil management perspective. We discovered that, on our clay soils, sediment traps were not effective at reducing movement of sediment to water, but some of the soil management practices described in Chapter 3 can help to do so.

The other important source of phosphorus in water is us. Sewage treatment works are the major source of phosphorus in summer and early autumn when the ecological impact is greatest, even if the overall annual load is greatest from agricultural land. Domestic sources of P have the greatest impact on aquatic wildlife, but losses from farmland represent the greatest loss of nutrients from the system. We need to address both sources to protect both wildlife and finite nutrient resources.

We have shown that, for aquatic wildlife, it is also possible to ‘escape’ catchment scale nutrient enrichment by creating small clean water ponds in micro-catchments which are not affected by domestic or agricultural sources of nutrients. This is particularly relevant as ponds are inherently more species-rich than other forms of water body.

We have also shown that the installation of simple permeable timber dams in headwaters can reduce downstream flood risk. This is a relatively simple measure which complements traditional engineered flood risk management downstream, although as our results also show, there is a limit to which we can protect ourselves from the impact of climate change. What we can do about climate change is discussed in Chapter 9.

New approaches to wildlife management

In chapter 4 of Farming with the Environment I presented the results of our research into the very wide range of wildlife associated with the farmed environment at Loddington. But nationally and globally, the abundance and species diversity of wildlife has declined over the past decades. In chapter 5 I describe the steps we have taken to reverse this decline through the development of practical evidence based habitat creation and management.

It’s hard to imagine that, when the Allerton Project started thirty years ago, it was common practice to spay out vegetation in hedge bases. Today, farmers are encouraged and economically supported to create and manage perennial grass margins around their fields to deliver a number of environmental benefits. Research at the Allerton Project was instrumental in that shift in mindset and agri-environmental policy.

We investigated arable weeds in field edges, habitat use by nesting birds, and the abundance of beneficial invertebrate predators of crop pests such as aphids. Beetle banks, low grassy banks through fields, were developed by the GWCT in the late 1980s as a means of getting these beneficial invertebrates further out into the cropped area, and we continued the development of these at Loddington in the 1990s.

We explored the potential of numerous flowering plants as a foraging resource for pollinating insects such as bumblebees and solitary bees, improving our understanding of how both naturally occurring plant species, and species that could be sown to create new habitat contributed to the conservation of these beneficial insects.

Now widely adopted winter bird food crops were developed at the Allerton Project in the 1990s under contract to the then Ministry of Agriculture, Fisheries and Food (MAFF). We looked at the use of a range of seed-bearing crops by birds in winter, and as a result were able to design seed mixtures to meet the winter food requirements of bird communities on individual farms. These were so successful that seed food became depleted by January and we provided the evidence base for provision of supplementary seed through the second half of the winter, now also a Stewardship option.

In terms of existing farmland habitats, we researched the birds and invertebrate communities associated with hedges and the influence of hedgerow structure on nesting success of birds. We also explored options for improving ditches for wildlife, prolonging the period in which they held water into the summer to the benefit of aquatic invertebrates and several bird species. Land and water management to benefit aquatic wildlife in ditches, streams and ponds is covered in more detail in Chapter 6.

Wildlife and our food

As a society, we have become disconnected, not just from the sources of our food, but from the very concept that the process of food production is integrated with countless wildlife species. In Chapter 3 of Farming with the Environment, I describe the results of our research into the role of life in soil that is used to grow food. Chapter 4 extends this to above ground wildlife – pollinating insects, crop pest predators, and other species that have evolved over millennia to share the farmed environment with us.

Thirty years of wildlife monitoring provide exceptional data for the Allerton Project’s farm at Loddington. We have also carried out research into habitat use by a wide range of species, including grass, hedge and woodland field boundary habitat use by crop pest predators such as spiders, and ground and rove beetles.

Our work on pollinating insects has revealed how their abundance today is limiting fruit-set in hedgerow shrubs such as blackthorn and hawthorn, and landscape scale surveys provide an insight into the enormous range in abundance of wild bees across a range of sites. We have used spatial models to estimate how wild bee numbers might have changed historically, but more importantly, how their numbers could be restored through future land use change.

Six species of grasshoppers and crickets have colonised the farm, largely in response to climate change, during the first fifteen years of the project. Despite national declines in abundance of moths, our long-term monitoring shows that moth numbers have increased by more than a third at Loddington over the thirty years, with the number of species present also increasing by around 20%. Overall songbird numbers doubled within the first six years of the project and much of our research over the years has been on how songbirds use the land we are managing to produce food.

For example, song thrush nests that successfully produce young have a higher proportion of pasture grazed by sheep within their foraging range than failed nests which have more arable land. Yellowhammers change from one crop to another through the nesting season when gathering food for their young, so crop diversity within the foraging range is likely to increase survival. We also have detailed information of the diet of many birds that forage for invertebrates on productive land during the breeding season.

Our research has shown that the land that we are managing to produce food is not just supporting wildlife, but that in some cases those species are increasing in abundance, many are beneficial to food production, while others are iconic species that we appreciate in their own right. Developing methods of further improving the farmed environment to benefit this full range of species is the subject of another chapter.

Soil - the life support system

It is right that soil should be the subject of an early chapter in my recently published book, Farming with the Environment – Thirty Years of Allerton Project Research. The health of our soil literally and metaphorically underlies the ecosystem on which we all depend. Not least, it is fundamental to farming.

Almost by definition, soil health is dependent on biological activity and much of our research over the years has focused on life in the soil, the role it performs, and the influences on it. Earthworms, collembola and microbial fungal and bacterial communities all perform important functions, and the soil also supports larval and pupal stages of many invertebrates that are predators or parasitoids of crop pests.

We have found that physical properties, especially compaction of our clay soils, reduce biological activity and abundance of some earthworms and other invertebrates. We have demonstrated that compaction limits water infiltration rates, contributing to surface runoff and loss of soil and nutrients to water. Using our Gasmet multi-gas analyser, we have found that emissions of nitrous oxide, a greenhouse gas with three hundred times the global warming potential of carbon dioxide, are substantially higher from compacted soils than well-structured direct drilled land. In a direct drilled system, sub-soiling alleviates this problem without the negative impacts on soil function associated with the more traditional approach of ploughing.

Soil organic carbon also influences soil biology and water infiltration rates. Comparing plough and direct drilled plots, our research reveals that microbial activity and diversity, and associated CO2 emissions are higher in the latter but that direct drilled plots are also associated with higher soil carbon. We are continuing to explore this apparent anomaly. We have also explored the influence of reduced cultivations on surface runoff and loss of sediment and nutrients from arable land.

We have found that cover crops intended to reduce soil and nutrient loss before spring crops can have some benefits in supressing weeds and encouraging earthworms, with subsequent benefits to cropping, but only where cover crop establishment is really good, and this can be challenging on clay soils. If not managed too intensively, some modern deep-rooting grass cultivars have the potential to sequester carbon in a stable form below the plough layer, and to increase water infiltration rates, contributing to catchment scale targets for water quality and flood risk management.

Such wider benefits, extending far beyond the soil at the field scale, also include positive contributions to terrestrial biodiversity within farming systems, a topic covered in the next chapter of the book.

The Long View

This is the first of a sequence of blog posts based on chapters from my latest book, ‘Farming with the Environment: Thirty Years of Allerton Project Research’ which was recently published by Routledge. Logically enough, I am starting at the beginning, not the beginning of the Allerton Project, but the earliest evidence we have for agricultural activity on the farm at Loddington in Leicestershire.

Archaeological fieldwalking has revealed the presence of Neolithic flint scatters, Iron Age iron smelting, Roman farmsteads, and a small Anglo-Saxon settlement. The size of the village at Loddington grew during the Medieval period, only to contract again as a result of plague. Then the Medieval open field farming system gave way to enclosed fields for grazing livestock, with only limited arable production until the Second World War threatened national food security.

The subsequent period has seen a radical change in food production, and in wider society. The science-led Green Revolution was associated with a move towards high external input agricultural systems, simplification of crop rotations, and an increase in scale. The negative impacts of this on the environment, and an increasing realisation that agricultural and environmental objectives are integrated, inspired a move towards agri-environmental research. It is worth considering how past farmers would regard our current farming methods and how future generations will judge their sustainability. The GWCT’s pioneering ecological studies, and the wide-ranging research at Loddington have been at the heart of efforts to ensure that agricultural and environmental objectives are met simultaneously.

Members of the local farming community who remember the farming systems of the 1930s have contributed verbatim to the book. They bring to life the practices adopted at the time. Understanding the evolution of farming systems through history provides an enlightening context against which to consider how food might be produced in future. Such historical knowledge also strengthens local identity, establishing ownership of current agri-environmental problems and opportunities for change.

Knowledge of how wildlife has responded to historical changes in land use is much more sketchy than the knowledge of land use changes themselves. Systematic records of wildlife have been kept only in recent decades, supplemented by more casual observations from the late nineteenth and early twentieth century. Together, these provide an insight into the changing fortunes of a range of species in response to both land use change and other factors.

Pollen records provide evidence of longer-term ecological change, and we have also used our understanding of current ecological processes to make a tentative estimation of previous aquatic invertebrate and wild bee communities for example.

But for most of us, the wildlife we experienced in our childhood provides a subconscious benchmark against which to assess the current status of wildlife species, and more worryingly, our aspirations for future change. Understanding longer-term historical changes in land use and species abundance provides essential context for developing plans for increasing wildlife, alongside the maintenance of food production, but a scientific understanding of how these are integrated is vital. That is the subject of subsequent chapters in the book.