The scientist Lluís Gómez Gener has carried out research that focuses on studying the hydrological, biogeochemical and ecological processes, both in peat bogs and high-altitude streams. mountain taking into account the current context of environmental change.
Lluis Gómez Gener and his team load the van and drive to the Vall de Molières, the border between Alta Ribagorça and Vall d’Aran. It is there, right at the entrance to the Vielha tunnel, where the the high mountain scientific station led by the University of Barcelonahe ECAM.
The researcher together with his technical staff carefully set up the portable laboratories and prepare the material to go out into the field: we will go with them into the National Park of Aigüestortes and Sant Maurici, and the Natural Park of the High Pyrenees.
It is from 2,000 meters above sea level where Lluis’s research begins, so it is time to load backpacks and we climb towards the headwaters of the Pyrenees rivers. Up there, where the weather conditions are extreme in both summer and winterthe team has installed various environmental stations to constantly monitor high-quality rivers. mountain.
Lluís’s research focuses on the study of the hydrological, ecological, and biogeochemical processes of high mountain streams and peatlands in a context of environmental change. More specifically, in the C-IntrMont project, financed by the la Caixa Foundation, he studies how these processes are affected by intermittency – the sporadic or seasonal drying of river courses.
Rivers…intermittent? in the mountains
In 1972, the crew of the Apollo 17 spacecraft photographed planet Earth in color for the first time and named it “The blue marble” because of the view it offered from space. Almost three quarters of it is covered by water! Now, of this only 1% is found on the earth’s surface, creating the freshwater ecosystems: wetlands, lakes and rivers.
When we think about the bodies of water that surround us, we tend to think that they are a static photograph, that they are always like this and, perhaps, they bring more or less water when it rains. But the reality is different: more than half of the planet’s rivers are intermittent and it is estimated that this percentage is increasing due to the effects of climate change and human extraction.
Intermittent rivers are found in basins with arid and semi-arid climates, such as the Mediterranean, since they combine the water deficit and high temperatures during the summer and the sudden abundance of water with the storms of the fall and spring.
However, they also exist in other colder and humid regions such as the alpine ones, specifically in the headwaters, since the basins are very small and are closely linked to seasonal precipitation in the mountains or melting snow.
“In a high mountain context “We are seeing how seasonal snow disappears earlier and hydrographic networks contain more sections that remain dry for longer periods of time,” says Lluis Gómez Gener, postdoctoral researcher at CREAF.
blue life
Despite its relatively small size, the Freshwater ecosystems host almost 10% of the world’s known speciesturning them into spaces of extremely high biological and ecological value. The biological communities that inhabit intermittent rivers suffer changes in environmental conditions and have strategies to withstand the lack of specific water.
For example, many species of aquatic insects migrate after metamorphosis, acquiring terrestrial life forms and doing away with the need for water. On the other hand, all those strictly river specieswhich need a constant flow of water, migrate before the river dries up.
“The problem is when change is unexpected and constantas is happening more and more with recurrent droughts, and many species die,” Gómez-Gener explains to us as we climb the Ribereta del Contraix ravine to the last high mountain experimental station.
In some cases, rivers are reduced into isolated pools that remain throughout the dry season and do not disappear. These rafts are a refuge for many species (such as some fish), but the conditions that appear increasingly less compatible with life.
This happens because water heats up like soup with rising temperatures, dissolved oxygen decays, and resources and space dwindle, causing increase competition among the remaining individualsamong other consequences.
They are every time minus the species that can withstand these conditionsand those that do are very well adapted. High-quality aquatic ecosystems mountain They help regulate, among other things, the water reservoir of the lower hydrographic basins.
He Climate change is forcing altitudinal migration of ecosystemscausing those from high levels to be replaced by others from lower levels. On the other hand, the difficult access and harsh winter conditions mean that high-quality aquatic ecosystems mountain They are among the most pristine, although the human introduction of invasive species seems to be inevitable.
These two reasons make it extremely important protection and conservation of high mountain ecosystems and speciessince “they help regulate, among other things, the water reservoir of the hydrographic basins on which we all depend,” says Gómez Gener driving a van back to ECAM after a long day in the field.
Las high mountain conditions are indicators that the increase in temperatures due to global warming is one of the influencing factors on the survival of species, which must adapt to the changes that this causes.