Advancing soil health for sustainable agriculture: Insights from the SoilX project

Could you give a brief overview of your project – what are the main objectives and expected outcomes?

"The SoilX project explored how soil management practices can reduce the impact of climate change-related weather extremes, like droughts and heavy rainfall, on crop productivity. The project combined data from long-term field experiments, simulation modelling, and socio-economic interviews to evaluate adaptation strategies.

"Field campaigns measured soil properties in long-term experiments across Europe using a standardised sampling and analysis protocol. These experiments compared treatments with different levels of organic matter inputs and tillage intensities. We developed an R-tool called SoilManageR to analyse the data, which synthesises management information into continuous indicators for advanced statistical analyses. Simulations with soil-crop models evaluated the potential benefits of soil-improving management practices across Europe under climate change projections.

"The modelling results showed that climate warming leads to a decrease in soil organic carbon and degradation of soil structure, reducing water infiltration and retention in the crop root zone. While improvements in soil structure can help buffer drought impacts, the benefits were limited because differences in soil properties between treatments in the existing long-term experiments were small. This highlights the need for new long-term experiments focused on soil health and climate resilience.

"Socio-economic studies revealed that farmers' adoption of soil management strategies depends on their priorities and viewpoints. They suggest that diverse strategies to promote the uptake of soil management improvements are likely to be most successful.

"Overall, the project emphasises the need for diverse, tailored strategies to improve soil management practices, considering different farmer motivations and regional conditions to enhance resilience to climate extremes."

Image description: Soil and earthworm sampling in a long-term field experiment at Säby in Uppsala. (Photo: Olivier Heller, Agroscope, Switzerland)  [on the photo from left to right: Péter Garamszegi, Elsa Arrázola,  and a bit of Rebecca ter Borg…, all from the Department of Soil & Environment].

How does your research relate to the One Health concept?

"Soil health plays a critical role in ensuring sustainable agriculture, ecosystem functioning, and overall public health. Soil management is essential to maintaining, improving, or restoring soil health. Soil health is defined as “the continued capacity of soil to function as a vital living ecosystem that supports plant, animal, and human life.” Healthy soils support resilient (agro) ecosystems. Arable soils provide food and feed, but they also deliver a range of other ecosystem services, including climate regulation, habitat for a vast diversity of organisms, as well as water regulation and purification.

"In SoilX, we specifically investigated if and how we can improve soil structure and functioning through soil management practices. Soil structure impacts water infiltration, water retention, and water supply to crops – features that are particularly relevant under extreme weather events such as droughts or heavy rainstorms. Improving soil structure is therefore critical to securing crop productivity, linking healthy soils to human nutrition, and feed production for livestock. Moreover, well-functioning soils are essential for flood control and contribute to climate mitigation, which directly or indirectly links to human health."

What do you consider the key challenges and opportunities in your research area for advancing sustainable agriculture amidst the impacts of climate change?

"One of the key challenges is how to prepare soils and cropping systems for contrasting weather extremes: too little and too much water, and we need to know when they happen (sometimes even within the same year, such as last year). It is a challenge to know what measures to take on which soil (soils are very diverse) and in which climate (i.e. site-adapted management). There is no 'one size fits all', and we must consider trade-offs between soil functions – a particular practice might increase soil organic carbon but decrease crop yields. Thus, it is important to keep knowledge exchange with farmers active to asses which practices are (technically, economically) possible and meaningful in just that region. Avoiding soil degradation, e.g. soil compaction, is key – while the process as such is natural science, the problem, caused by heavy machinery on moist soils, is complex and interlinked with the agricultural market.

"The challenges are, therefore, multifaceted, from a better understanding of processes within the soil system, improved quantitative knowledge of how soil properties and functions change due to soil management, long-term predictions of soil and crop management strategies on soil ecosystem services, including crop production in a changing climate, to understanding interactions between soils, climate, socio-economic factors, and human behaviour.

"Opportunities are that soils play a vital role for societies and that there is a potential for healthy soils to help tackle the current and future challenges in terms of food security and climate change. Knowledge can be used to develop site-specific (i.e., dependent on soil x climate x socio-economic context) solutions."