The need for change
Our current agricultural system is under pressure. We are increasingly seeing the negative effects of intensive agriculture on our natural systems. Nitrogen emissions damage natural areas, insect populations are declining, and our landscape is becoming simplified. Extreme weather conditions, such as drought and heavy rainfall, are also becoming more frequent and threatening crops worldwide. Additionally, agriculture is heavily dependent on external inputs such as artificial fertilisers and crop protection products. This makes the system vulnerable, especially when these resources become less available due to rising costs or strict regulations.
"We need to look for alternatives, for an agricultural system that is less dependent on external inputs and makes more use of natural processes," says Rosa Boone, researcher at uu77. Organic, regenerative and nature-inclusive farming methods are examples of this. "What these systems have in common is that they make much more use of natural processes in the soil. Research has shown that soil life is a driving force behind all these processes, and that the intensity of land use can affect this soil life."
Research in the Ooijpolder
Boone studies these processes in the Ooijpolder, where she collaborates with farmers, ecologists and organisations such as LTO and Staatsbosbeheer. In her research, she compares three types of grassland: conventionally managed grasslands, extensively managed grasslands and semi-natural grasslands managed by Staatsbosbeheer. In these grasslands, she measures VOCs emitted by soil life, and these substances appear to be rapid indicators of changes in soil management. "In the past, farmers would smell their land to determine its condition," says Boone. "Those scents could still tell us what's happening below ground."
Faster insights through soil scents
The research has now identified sixteen different VOCs that can indicate how grassland management influences soil life. This is important because more and more farmers want to switch to more extensive forms of agriculture. "Farmers want to know whether their adjustments are affecting soil life. With traditional DNA analyses, it often takes years to see changes, but differences in scents can be demonstrated much more quickly."
Stability and resilience
Initial results show that fungal communities in extensively managed grasslands are completely different from those under intensive management. Additionally, grass production in extensively managed grasslands appears more stable, even during periods of drought. It also seems that extensively managed grasslands function slightly better than conventional grasslands. Boone explains: "These are three strong indications that soil life could have an effect on the functioning of agricultural land. The choices we make about agricultural land management could actually affect soil life, which in turn influences soil functioning. This is especially important if you're aiming for resilient soils that can withstand disturbances such as drought. Fungi in organic grasslands can, for example, help plants access water better," Boone explains. "This could make these grasslands more resilient to extreme weather conditions."
No universally good soil
However, Boone warns against hasty conclusions about what constitutes a 'good' soil. "There is no single good soil. A natural grassland can have very high biodiversity but low production, and a production grassland vice versa. We are looking for the optimum balance between production, biodiversity and functioning. An organic farmer has different soil requirements than a nature conservator. It's about which functions you want to fulfil."
Key role for the soil
The research shows that soil life can play a key role in the transition to sustainable agriculture. By better understanding how soil life responds to different forms of management, farmers can be more effectively supported in this transition.
BetaBoost
Each month in the BetaBoost, you'll get a sneak peek into ongoing research at the Faculty of Science and its social impact. Do you have a question about a current topic you'd like a scientific perspective on? Contact us on communications-science[at]ru.nl.
Photo: Femke Reijerman
