Tristan Charles Dominique is a researcher at the Institute of Ecology and Environmental Sciences of Paris (iEES Paris). Together with Pere Pons, from the University of Girona, co-leads the area of expertise (work package) of FIRE-ADAPT called “Biodiversity conservation”. In this interview, he explains what this work package is about.
What is the goal of work package two – “Biodiversity conservation”?
Recently, there’s a growing recognition that fire is not necessarily bad for diversity. Some wildfires have existed before living things. Wildfires can harm diversity in some systems, but they can also be necessary for diversity in others, and we know very little about this. Our work package is gathering all the information on this matter and synthesising it. We are also generating guidelines to recognise if the diversity of a system could benefit from fire.
What do you expect to see?
As researchers investigating fire, many people ask us “is it good or bad?”, and this is typically a question we cannot answer. We can say fire promotes or demotes part of the diversity, and this is one more aspect to consider when you want to use fire to manage the landscape. Our interest in the positive effects of fire doesn’t mean that we want to promote it unconditionally. What we want is to provide arguments that together with many other arguments, like whether it is a risk for people or forests, we can use to make decisions that acknowledge diversity.
For example, it might be the case that if you remove fire from some parts of the landscape, you lose diversity. Then, this is something to consider in your land management plan. It doesn’t mean that fire is good or bad, it just means you are going to lose some components in your landscape.
How do you study the relationship between biodiversity and fire?
In the “Biodiversity conservation” work package, there are specialists in plants, mammals, birds, insects, and microorganisms. My speciality is plants, and something unique about them is that they cannot move, so they are subject to the environmental conditions. If these are good, all fine. If not, they can’t flee to look for better conditions. In the case of fire, if it gets to them, they have to deal with it.
Many plants can create fire because they are flammable, like pine species whose needles burn on the ground or grasses in the savanna. Our first question for plants is which ones can do this.
The second main question is which species can survive fire and how they do that. Is it because they stand the flame? Do they hide from the flame below ground? Do they grow up in places where the flame can’t trouble them?
The last question, and one very important for us, is which of these species needs light. When fire is frequent, it opens the system, providing light for all organisms. Many of the species that love fire also hate the shade. This means that, if you remove the fire, the long-term effect is the loss of these species.
An example of a trait you study to investigate the relationship between plants and fire.
The most well-known example of information that tells us if plants are adapted to a fire frequency or not is the thickness of the bark. By the way, the cork used to close wine bottles is directly extracted from the bark of a fire-adapted tree species that produces a lot of bark (cork oak, Quercus suber). The real question is how fast this bark is produced (the bark production rate). We can calculate it by knowing the bark thickness and the age of the tree.
The bark production rate tells you how fast a plant can be protected against the first fire that is going to encounter. For example, if it needs five years to produce its bark to survive one fire, then most probably the fires in the system where it has evolved occur every five years or more. If there were fires more frequently, this species would die.
How does your FIRE-ADAPT research relate to the other areas of expertise of the project?
When we talk about biodiversity, as biologists we think in terms of hard science (number of species, how ecosystems work, etc.), but the social aspect is very important: how we define, perceive and value it. A good example is the flag species. If you think about biodiversity conservation in big terms, most probably a polar bear will come to your mind. It turns out the polar bear alone is a minor contributor to its ecosystem because it’s a top predator. However, we relate to it because it´s a charismatic animal that motivates people to take action. In fire-dependent systems, how could we choose the flag species?, the fire-dependent species that would move people and they could say “oh yeah, for sure, this species is important“. In this sense, we get help from the sociologists in work package three – “(Inter)cultural services and human well-being” to guide us in defining diversity.
We also work with colleagues in work package four – “Modelling and forecasting”, to whom we send the data we collect and with whom we build models of scenarios managed differently, and in work package one – “Carbon dynamics”, since diversity and carbon fluxes are merged. You can’t understand one without the other.
What will this work package produce?
We will provide a review of the diversity associated with fire, accessible to both scientists and non-scientists, explaining that part of the diversity can depend on fire and part can be sensitive to it, and that, therefore, integrated fire management has to include the use of fire to promote biodiversity. This is difficult because the idea of burning for diversity is new and raises many questions about where and how to burn, what the desired state we want to achieve is, and what the result will be.
We will also put together and share protocols to study diversity in terms of fire. Fire is structured in space and time differently than other environmental factors that we are used to consider. Therefore, the procedures to get the data we are looking for have to be tailored to our research’s goals. Our idea is to make these protocols accessible to researchers and practitioners and standardised, so they can be applied anywhere in the world. This way, we can compare the science and provide a more global perspective on what the diversity associated with fire is.
What are the next activities where you are involved that you would like to highlight?
In terms of work package two, Pere Pons and I will deliver a workshop at the Brazil Study Hub, in June, to exchange and propose standardised methods to study and monitor diversity. While in Brazil, we’ll also carry out fieldwork to collect data and learn about the people’s perception of fire-dependent biodiversity.
And in terms of the France Study Hub, all co-organisers are planning the activities for the consortium taking place in early 2025. We would like to show where fire is a success story in France, but it wouldn’t be representative of the broader picture there. In some parts of the Pyrenees, low-intensity fire is part of the landscape. It’s not frightening to people because they manage it, and people value it for the diversity it provides and value it for how it can help renew the pasture. But in most places in France, there’s no large-scale prescribed burn, people are afraid of fire, and there are actions to tell that fire is bad for diversity. Close to where I live now, fire has been completely excluded from the landscape. We have observed over the last 50 years a very important closing and homogenisation of the vegetation, and it’s something I think that is also worth saying, what happens when we remove completely fire, and how it could affect diversity in the long term.