What do people tend to overlook about soil?
Many people think of soil as dirt, but it is much, much more. Healthy soil is full of life, and we depend on it for the food we eat and many aspects of the air we breathe and the climate we live in. I think a lot of people do not see soil in this way, particularly if you have grown up and live in an urban environment, and that’s a broken relationship we need to address.
What makes soil so complex?
Soil is a dynamic system where microbes like bacteria and viruses and tiny animals and plants interact in all sorts of ways. We see a lot of these interactions in the “rhizosphere”, which is the narrow zone of soil surrounding plant roots. For example, the plant roots release food for microbes, and in return, the microbes can help plants by supplying specific nutrients and by suppressing organisms that cause disease or harm to the plant. It is a busy, highly interactive space that plays a crucial role in plant health and soil function.
How does soil link to climate?
Soil plays a crucial role in storing and releasing carbon and other greenhouse gases. This means it can act as both a sink, storing carbon, and as a source, releasing it into the atmosphere. And because soil is alive and constantly “breathing”, understanding these processes is essential for predicting and managing climate change.
How do you research such a complex system?
In my lab we both measure soil biodiversity and build mathematical models of the relationships that happen within soil and the ones that link organisms above and below the ground, so we can begin to understand how entire ecosystems function. This means we can model how carbon moves through a grassland ecosystem, for instance. These models simplify the messy reality, but they help us to understand patterns, such as how energy flows or how populations change over time. AI is making these models more powerful, but it is still a challenge to collect reliable “real life” data to make the models meaningful. That remains a frontier in the field.
How did you become interested in soil science?
I grew up beside the sea in Italy, and when I was a kid I had my heart set on being a marine biologist. Then as I studied biology at university, I became really interested in ecology, and how species form communities and ecosystems. Soil turned out to be an ideal system for this, because even a tiny sample of soil contains an incredible diversity of life. Over time, that curiosity grew into an interest in how ecosystems function as a whole.
What do we need to do as a society to improve soil health?
I think as a society we need to understand how much food we really need. We do need to grow food, of course, but some types of food take up more physical and ecological space than others. We also have an enormous problem with food waste in many parts of the world, which means we put pressure on soil just to generate biomass in the form of uneaten food that needs to be disposed of. As a society we really need to be aware of the implications of this, and as consumers we need to use our power and make more informed choices about what we buy and eat.
What do you like to do when you are not researching?
In the summer, I love free diving, especially when I visit my parents back in the Med, it is just a tiny bit warmer over there. The rest of the year, since a young age, I practise the sport of fencing.