Manuel Marey: «In Galicia, the fire was one of the best land management tools»

-Why do we in Galicia witness this drama year after year without finding effective solutions to remedy it?

-As I said before, we have to put the problem in context. In Galicia, fire was one of the best and most efficient tools for land management. Our ancestors perfected the technique of fire in order to be able to use the land for livestock for centuries and also to put specific areas to agricultural use. Without fire, it would be impossible to feed a very large population, much larger than the average for the rest of Spain.

However, it is true that in the last 4 or 5 decades, rightly or wrongly, fire ceased to be considered an instrument of land management, except in the case of controlled or prescribed burning, which is very limited in its use in Galicia.

As a result of this loss of the positive social component of fire, it came to have an exclusively negative component (it already had this, given that, in many cases, an area burning down was the result or symptom of the conflict that existed there).

Well, fire came to be persecuted, and the State understood as a whole as the Administration established punitive mechanisms and instruments such as the Galician Fire Defense Service to persecute and extinguish the fire. In this way, numerous economic resources were allocated that were withdrawn from other possible actions in the territory. This is an old debate to which, in 2013, I had the opportunity to dedicate time and reflection in the article “From agrarian culture to the fire industry,” published in the magazine Grial, and in which I also dared to make proposals of political fiction.

In short, we had fires that, to a significant extent, were agricultural tools. To a lesser extent, they were the result of social unrest. And finally, those of natural causes, such as storms or droughts, were very limited.

As an indicative figure, our territory has changed completely in the last 60 years. I invite people to visit the website of the National Geographic Institute. I invite you to locate yourself in your area and observe the evolution of its forest mass over the years. You will see, in most cases, the enormous transformation undergone from farm to farm, parish to parish and town hall to town hall, with a clear vector towards the stratification or afforestation of these plots as a result of the disappearance of livestock farms.

These, after all, also meant the disappearance of the herbivores that fed on the biomass produced there or even of the agriculture that removed the biomass. At the same time, it was also a question of the Administration's success in reducing the area burned, given that fire removes biomass.

And, in the paradox of the fires, here is the key: land management. There is more and more biomass, more continuously, with a greater degree of stress to a certain extent. When the conditions for burning occur, it burns with more intensity and over a larger area simultaneously. Furthermore, the firefighting services, no matter how efficient they are, constantly run the risk of being overwhelmed.

-In the case of fires, society and the media often tend to simplify possible solutions when, in reality, it seems that we are facing a very complex problem that requires what English speakers call CPS (Complex Problem Solving). Is this the case? Can we find simple solutions, or do we need a more disruptive approach?

-As I was saying, fires are undoubtedly a problem for our society today. We cannot say that they retain that positive component, as I mentioned before. And we can say that now forest fires are also a European problem, something that did not happen 15 years ago because, in Europe, the issue of fires was confined to the Mediterranean area. But now it has become widespread, which has a clearly negative component, but also certain advantages in the search for solutions.

Now, it is the turn of the solutions. First, we must understand the flow diagram that a forest fire needs to develop. The first stage is the accumulation of fuel in the territory, something that happens in the long term. Then, in the second stage, the moisture content of the fuel comes into play. This happens weeks or days before the fire breaks out. Third: Ignition. These are anthropogenic causes, and within these, those caused by negligence or accidents, or natural causes, which include lightning from storms or droughts, for example.

Then, on the fourth rung is meteorology, corresponding to the temperatures, relative humidities (day and night) and winds that will occur in the hours or days following ignition. And finally, it is the turn of the fifth factor, simultaneity. This refers to the possibility of different fires breaking out at the same time in an area served by one firefighting service.

All these factors must combine for large fires to occur. And which ones can we act on? We can act on the first and partially on the third and fifth.

In the case of the first, related to the accumulation of fuel, it is critical to promote fire-resistant forestry, as well as agriculture and livestock farming, with the aim of removing biomass. With regard to the third and fifth factors, we can act by providing fast and agile firefighting services.

-What happened a few days ago in California showed once again that this is a global problem. Are there coinciding structural causes, or does each territory have very specific characteristics that differentiate it from others?

-The flow diagram is common in all cases. Obviously, there are different spatial and temporal components or characteristics in each area. These differences are more noticeable and influential in wildland-urban interface (WUI) areas.

In short, wildfires anywhere in the world follow common patterns of behavior. That is to say; they are classified according to the amount and type of vegetation, how it is distributed horizontally and vertically, the moisture content of the fuel, the meteorology or the orography.

Thus, fires can be driven by wind, by slope or by a combination of both: scrubland fires, crown fires if they climb to the top of the trees, fires that generate pyro-clouds, etc. Consequently, the firefighting services classify the fires and apply the most suitable techniques for each type of fire (direct attack, aerial means, firebreaks, etc.).

When we are in areas such as the northern part of the city of Los Angeles, the orography, the urban population model, the building model, the typology of the buildings, the construction materials and so on change substantially with respect to, for example, our population model. Therefore, the behavior of the fire is going to be very different.

The social component is also very important, that is to say, the level of information, training and behavior of the population in fire situations. Likewise, the debate over whether to evacuate or confine is very interesting, as is knowing the level of organization of the administrations responsible in the event of fires. When entering urban areas, the chain of command and the capacity for decision-making based on legislation can change substantially. This legislation classifies fires on a scale of 0 to 3, with 0 being a forest fire.

-Perhaps these are not the best days to talk about climate change when we are witnessing such controversial decisions as the one the US has just taken by abandoning the Paris Agreement, but... To what extent is climate change going to determine the evolution of this problem at a global level in the coming decades? Is it possible to make any projections?

Different authors propose different models. In my experience as a researcher who reviews them, but does not model future fire behavior at various scales, I can describe the ones that seem most coherent to me. Although, like any forecasting model, only time will tell how accurate they are.

I would like to avoid two types of models. Some are those that are more catastrophic, which establish apocalyptic models based on projections or trends of certain variables (such as temperatures or lack of rainfall) and which, in addition to being unlikely, would in themselves imply reductions in the growth and accumulation of biomass. Let us remember that this is the first point in the fire flow chart, something that their models do not integrate.

I would also shy away from models that have no hope at all in something like the ability of human beings to solve problems. Something that contradicts history, which shows us that we are creative beings. In this type of model, the extinction capacity is established as static, something that is totally incorrect since substantial progress is being made in response times, coordination capacities, increase of the extinction temperature limit, etc.

To give a figure, which we would place around the year 2035, in climatological terms, we can say that we would have about 15 more days of window of opportunity for fires in Galicia within the foreseeable threshold. This would be distributed mainly at the end of summer and, to a lesser extent, at the beginning of summer. In terms of fuel or vegetation, I do hope and believe that we are going to do our homework and that we are going to have more livestock in the territory and less biomass on an ongoing basis. I want to be optimistic.

-The Projects and Planning (PROePLA) research group from the Campus Terra analyzed tens of thousands of fires worldwide. Perhaps one of the most striking conclusions is that most of the fires occur near inhabited areas. Why? Is there an underlying cause?

-I would like to clarify that, in our study, we did not segment the fires according to their proximity to inhabited areas. What we did was measure the distance from the point of ignition of all the fires that exceeded the established quality control so that there was a guarantee of the correctness of the position of the point of ignition in relation to the nearest building.

Then, in a hexagonal grid in which each cell had a surface area of 7774 km2, we carried out the analysis using a non-parametric test due to the lack of normality of the data (specifically the Mann-Kendall test) to see if, over time, they were significantly approaching or distancing from each other or not.

-The research you carried out would make it possible, just as an example, to create much more efficient territorial planning policies to deal with problems such as fires. Are you hopeful that this will happen? That the work of such well-known research groups as yours will be taken into account by governments?

-That's a good question, and it would give rise to a good debate. Our duty and, at the same time, our interest is to generate science that can later be transferred to technology and legislation, which will allow the society to which we are indebted to progress. I believe that it is the duty of every researcher or research group at a public university, in this case, the University of Santiago de Compostela, Campus Terra and the Higher Polytechnic School of Engineering.

How do we interpret this duty? Well, we have been studying fires for 20 years, first in Galicia, then in Spain and now worldwide. Our work serves to understand how fires have behaved up to now, providing verifiable empirical scientific knowledge that serves to advance science.

Thanks to this, we know more than we did about where fires start; we know about different places and different times, and we understand how they are evolving and how this evolution is not homogeneous...

This last point is very important, because recently I was interviewed by people from different autonomous communities in Spain and, when asked why the fires had come so close to buildings in Murcia or Extremadura, my answer was always that it wasn't for me to answer, because I don't know the specific causes of this situation, for example, on the southern slope of the Sierra de Gredos or in the mountainous area of the Murcia region.

It should be researchers with greater knowledge of these specific regions who should answer the question. We make our data and the results available to them. This is about advancing science, but it is also about advancing technology because the firefighting services in these regions will have confirmation that they have a different situation from the rest of the environment.

In both Extremadura and Murcia, they will be able to understand that something different is happening, which they obviously already knew or sensed but which they can now confirm. With that in mind, they will be able to take the most appropriate operational measures, which, in the same way, legislators can establish through plans or laws to improve the situation.

In short, I think we do our job, which is none other than working in our offices for long hours, rigorously scrutinizing the data, obtaining results, subjecting them to scientific criticism and review, and explaining them in technical terms so that they can be understood and, to the extent that it is considered, taken into account, if I may be so bold.

-Changing the subject, the PROePLA group is promoting a project to create more wealth and employment associated with the exploitation of agriculture, livestock and the forestry sector in several regions of Galicia and Asturias. What does the project consist of, and what are the objectives that were set?

-Yes. We are working on two projects: CARES and MIXTURANDO. The Biodiversity Foundation funds both and we are trying to fulfill our task with them.

In this case, we are trying to influence the first point of the fires by limiting the accumulation of fuel, still without carrying out controlled burns or grazing, which also have their place. Rather, we are establishing productive programs that generate employment and activity in rural areas, especially in areas of high natural value, such as the areas of the Natura 2000 Network. In another published work, we found that they have serious fire problems.

We are excited because we consider that we are integrated into very competent teams and projects with a lot of knowledge of the territories and the production techniques that can be developed there, with the aim of providing economic opportunities for activities in the agricultural sector in the areas of the Natura 2000 Network.

-You also led a European project to regenerate water treated in sewage plants like the one in Lugo to use it for irrigation. The UN openly says that water will be the oil of the future...

-Yes, I am lucky enough to coordinate a research group such as PROePLA in which I have colleagues, friends and teachers of enormous human, academic and scientific value.

One outstanding case is Javier Cancela, who is a national and international reference in water management and with whom I have also been friends for more than 30 years. In the I-ReWater project, funded by Interreg-Sudoe, Javier leads researchers from France, Spain and Portugal with a goal as necessary as it is ambitious: to establish instruments, in this case, through a transnational strategy for the use of reclaimed water for agriculture.

Another characteristic of the PROePLA research group that I would like to highlight is that it is a group with a diverse level of specialization. This means that, since our foundation, with the impetus of Professor Carlos Álvarez, we are not a monolithic group specialized in a single subject without the capacity to change or adapt to the research needs of society.

On the contrary, we are adaptable, as engineers that we are, to the demands of each moment. Therefore, this versatility forces us to make greater efforts, but also to accumulate a broad know-how that allows us to relativize and contextualize the advances. As a result, our advances in science are transferred to technology and, finally, some of them to the legislative framework.