This article first appeared in our Organic September issue of My Green Pod Magazine, published 08 September 2023. Click here to subscribe to our digital edition and get each issue delivered straight to your inbox
Fossil fuel-based nitrogen fertiliser has changed the face of farming, allowing extremely high yields of nitrogen-hungry crops to be grown under intensive conditions.
Demand is being driven by the vast quantities of animal feed required by livestock systems that have undergone parallel intensification.
With bags of this fertiliser, farmers can grow ‘cash crops’ of cereals and oilseeds year after year, without pausing to harness the power of manure and plants such as clover, peas and beans to fix nitrogen back into the soil biologically.
This cycle incentivises the overuse of fertilisers – the Defra Soil Nutrient balance shows that in the UK almost half (45%) the nitrogen applied to farmland is surplus – and has created a system of farming that is acidifying the land, stripping soil of its nutrients, polluting our air and water and damaging biodiversity for generations to come.
All life on Earth requires nitrogen, but too much of it is bad for the planet – and the use of fossil fuel-based nitrogen fertiliser has allowed more to enter the environment than would naturally be restored to the soil through nitrogen-fixing plants used in traditional, rotational farming practices.
While we’re all by now familiar with agricultural emissions of methane and carbon dioxide, nitrogen has somehow managed to to slip under the radar.
A recent report from the Soil Association paints nitrogen fertiliser as ‘the overlooked driver of climate change’; its manufacture requires fossil fuels and the soils on which it is applied emit nitrous oxide.
This powerful greenhouse gas (GHG) persists in the atmosphere for an average of 114 years and is up to 300 times more potent than carbon dioxide.
Farming produces more nitrous oxide than any other sector; despite the significant greenhouse gas emissions from these fertilisers, the UK government does not have any plans to set targets to reduce their usage and they are not mentioned in the net zero strategy.
Achieving net zero emissions by 2050 means near zero emissions of nitrous oxide. The UK ambition to reach net zero by 2050 does not factor in ‘consumption emissions’ – the lifecycle emissions from imports such as fruit, vegetables and animal feed, along with their associated nitrogen footprint.
These consumption emissions make up 46% of the UK’s total carbon footprint, meaning we’re failing to account for a large chunk of embedded nitrous oxide emissions further down the supply chain.
A quarter of all nitrogen used for fertiliser makes its way back into the air and water as pollution; the global cost of this wasted nitrogen is estimated to be $100bn annually, in fertiliser alone.
Reactive nitrogen is soluble and when it gets into waterways can lead to huge algal blooms that reduce life in our rivers and seas and put coastal communities at risk.
Most of the UK’s protected habitats, such as marshes, bogs, meadows and woods, are at critical levels of nitrogen pollution, despite rarely having any nitrogen directly applied to them.
The government’s 25-year Environment Plan for England includes an ambition to return 75% of waters to a near-natural state; currently only 16% of England’s inland freshwater bodies are close to their natural state.
Without firm targets on reducing total nitrogen input this target might not be achievable; the Environment Agency’s own assessment is that, at the current rate of progress, the goal will take over 200 years to achieve.
The intensification of agriculture has stripped farming of its biodiversity; the broad range of grains, plants and animals that traditionally made a patchwork of farmland has been reduced to a handful of varieties and breeds, packed so tightly there’s no chance of light – or life – reaching the field floor.
These dense crops are more vulnerable to fungal infections, making farmers more reliant on synthetic pesticides that are unintentionally devastating populations of bee and earthworm, among many other natural allies to farmers.
Plants like cornflowers, once abundant on arable land, are on the verge of extinction, dropping 99% in 50 years.
UK farmland birds have seen a 48% decline over the same period and Europe has lost over half a billion birds in 40 years.
Pesticides and fertilisers have been singled out as the biggest cause, and global biodiversity assessments show excess nitrogen in the air and water as one of the most significant threats to biodiversity.
The UN Environment Programme’s Colombo Declaration recently launched a global ‘Halve Nitrogen Waste’ campaign, highlighting how improved nitrogen efficiency supports climate, nature and health goals, while saving $100bn globally annually.
The Soil Association is clear that if we’re going to fix the nitrogen problem, we need to start measuring fertiliser use and helping farmers transition to a system of farming that recycles nitrogen, closes nutrient loops and prioritises healthy soil – all while providing the right food to supply a healthy, sustainable diet to a growing global population.
We can feed the world without relying on the overuse of harmful synthetic fertilisers. In fact, even with the nitrogen use we see today, millions of people are malnourished.
Modelling suggests that in Europe, feeding a growing population a sufficient diet is possible (subject to dietary changes ) without the need for synthetic nitrogen, and while recognising planetary boundaries.
Agroecological farm systems work within natural cycles, like the nitrogen cycle, and help to improve soil health for nature, climate and food security though a shift to the circular use and management of nutrients.
A recent model by think-tank IDDRI laid a pathway for Europe to become agroecological by 2050.
Without the shortcuts of synthetic nitrogen inputs, agroecological systems rely on the health, quality and structure of soils to support crops.
It is these healthy soils that absorb run-off, filter nutrients and have a higher volume and diversity of soil microorganisms to break down nutrients more effectively.
It’s not an impossible ask; Soil Association Certification has been certifying farmers that grow healthy food – without synthetic fertilisers – for over 50 years.
Over the last year, three of the biggest fertiliser suppliers in the UK have made an incredible £5.45bn in profit. This shocking revelation comes at a time when much of the UK farming sector is in crisis.
Last year’s report by Sustain uncovered the tight profit margins for many farms, leaving little in the bank to buffer against volatile markets and few reserves to build on-farm resilience to the unstable and changing climate, leaving many farmers considering leaving the sector.
We have recently seen that governments are prepared to intervene on food access, availability and distribution. It’s time for the government to step up and set targets for reducing nitrogen fertiliser use, and support farmers to transition to nature-friendly farming methods, like organic, in order to reach their net zero targets.
By buying organic this Organic September, you’ll be helping to support a wholesale shift away from damaging and polluting farming practices, and towards an approach to farming that respects and promotes all-round health.
A recent study revealed that on average an organic farm system uses recycled nitrogen for 50-100% of total needs, while conventional systems, usually dependent on synthetic fertilisers, recycle only 10-30%.
Buying organic is a form of climate activism; in fact, it addresses many of the key environmental issues on which Brits want to see more government action.
Organic agriculture protects green spaces, slashes CO2 and other greenhouse gas emissions and reduces air pollution.
At the same time it boosts biodiversity and soil health, helping land to become more resilient to the threats of extreme weather. All while creating food that prioritises animal welfare and generates nutritious food that tastes delicious.
Support climate and nature this Organic September; click here to sign the petition telling the government: ‘there’s no net zero without fixing fertiliser’