Why soil is the foundation for sustainable agriculture

With the United Nations COP26 Climate Change Conference in Glasgow this November, researchers at Norwich Research Park are making great strides in understanding how soil influences our ability to grow crops in different environments, so that as a global community we can feed everyone healthily.

The Norwich Institute for Sustainable Development, launched at Norwich Research Park earlier this year with funding from the John Innes Foundation, is hosting the inaugural John Innes Foundation lecture on Tuesday September 7, which will be delivered by soil and sustainable agriculture expert Professor Rattan Lal of Ohio State University.

The Norwich Institute for Sustainable Development harnesses Norwich Research Park’s excellence to enable equitable, food-secure and sustainable futures.

Prof Lal, who won the World Food Prize 2020, will outline the key issues that threaten healthy soils and strategies to overcome them.

Pressing issues of the 21st century include global warming, food and nutritional insecurity, water scarcity, air pollution and loss of biodiversity. But vital progress to successfully address these critical issues is not yet on track to meet the Sustainable Development Goals of 2030 and suffered further setbacks due to Covid-19.

There are high hopes that the United Nations Food Systems Summit (UNFSS) being held later this month and COP26 scheduled for November will help speed up progress.

The UNFSS is urgent because, despite significant increases in the amount of food produced globally, 690 million people still remain undernourished, more than two billion are malnourished and these numbers are rising rather than reducing. Agriculture must now face the double burden of achieving these gains despite the risks climate change poses and producing more food without causing further habitat loss.

Moreover, improvements in food production are not without environmental costs. Farmland takes the places of natural habitats, reduces biodiversity and alters the conditions of the land it is based upon. As a result, soil health often suffers. Prof Lal has outlined three of the main agricultural practices that have undermined soil heath.

Firstly, the adoption of input-responsive crop varieties was critical to achieving higher yields, which were bred to respond to the application of high levels of chemical fertiliser.

Secondly, water availability and quality have been negatively affected. Farmers are experiencing water shortages and salination due to excessive withdrawal. Nutrient run-off from farmed areas has caused water ecosystems to be dominated by destructive algal bloom in response to the increased fertilisers in the water.

And thirdly, soil degradation has become a serious problem due to a number of issues including accelerated erosion, depletion of soil organic matter stocks, salinisation and nutrient mining. These issues are also sources of greenhouse gas emissions, especially nitrous oxide (N20) and methane (CH4), which are very damaging to the atmosphere. When combined with emissions taking place due to changing land use and forest clearance to make room for farm land, as much as 31% of all greenhouse gas emissions are attributed to agriculture.

Healthy soils are the foundation of our terrestrial food system and play an important role in mitigating and adapting to the impacts of climate change. The challenge is that in our current methods to feed the world, many soils have been degraded, contaminated and depleted of nutrients.

These growing threats to soil health must be addressed if we are to sustainably feed generations to come. Scientists and land managers must implement policies that protect soils in ecologically-sensitive ecosystems, manage soils of agro-ecosystems using evidence-based approaches and regenerate degraded soils to achieve net land degradation neutrality.

Researchers at the Norwich Institute for Sustainable Development are currently investigating a number of ways to provide healthy, accessible food without the environmental impact of current practices. These include greater focus on legumes that reduce the need for inorganic fertilisers in agriculture, crops that do not require pesticides that otherwise damage soil communities and approaches to shifting to plant-based diets that mitigate the environmental costs of keeping and feeding livestock.

The three main areas where COP26 and UNFSS can offer significant support to address these issues include:

• Identification and prioritisation of key game-changing solutions.

• Formulating and implementing policy interventions that empower farmers to adopt site-specific recommended management practices.

• Creation of a mechanism to reward farmers who adopt nature-positive systems of agriculture.

Professor Nitya Rao, director of the Norwich Institute of Sustainable Development, said: “We cannot achieve sustainable agriculture without healthy soils. We need greater knowledge of how to improve soil health and we need to ensure that this awareness becomes common practice.

“Prof Lal’s research is essential to realising this vision and we are delighted to have the honour of him sharing this crucial work at our inaugural John Innes Foundation lecture.”

For more information, please visit nisd.ac.uk