Echantillonnage

The retreat of glaciers threatens the biodiversity of the paramos

Olivier Dangles, contributor to the MOOC "Of Rivers and Man" coordinated by Grenoble INP, has studied the glacial streams of the high plateaus of the Andes for the past 10 years.
The p?ramos, the great grassy plains of the high plateaus of the Andes located between the forests and permanent snow, are privileged places for the observation of the effects of climate warming.
With his local collaborators, Olivier Dangles, a researcher at the IRD working in the tropical Andes for the past decade, has studied the contribution of glaciers to the downstream water courses that supply water to the city of Quito, the capital of Ecuador. "The water of these rivers comes from both springs and the glacier, in proportions that vary greatly depending on the climate." To determine these proportions, hydrogeologists measure the turbidity and the conductivity of the water (glacier water contains clay and is less mineralised), as well as the flow of the stream. The aim, among other things, is to gather valuable information for the management of the drinking water of Quito


IRD - Olivier Dangles


Biodiversity in danger
In parallel, scientists have observed that the water courses of the p?ramos shelter a very rich ecosystem, consisting of microorganisms, insects and crustaceans, most of which are endemic. "We have demonstrated that this ecosystem is closely linked to the balance of the mixture between glacier waters and spring waters. Thus, the glaciers play a major role in the dynamics of the aquatic systems of the p?ramos." This observation opens new perspectives for research on the consequences for this unique biodiversity of the gradual thawing of glaciers, which have lost 30 to 40% of their surface area in 40 years. “The disappearance of this exceptional wildlife would be a loss in terms of the conservation of these unique ecosystems.”