The Doñana marshes could disappear within four decades. The threat comes from climate change, with rising temperatures and decreasing rainfall “seriously affecting” these ecosystems that are symbols of the national park. In the worst case, they would disappear in 42 years, although the most optimistic range suggests that this moment would not arrive for another 189 years. The warning is that, “without adequate intervention”, we are heading towards an “ecological collapse”.
This situation has been reported for years, but now a study by the University of Seville is sounding the alarm. The results of the research are those that are seen daily in this area: a “worrying” reduction in the floodable surface and alterations in sediment dynamics, “which endanger the biodiversity and ecological balance of the area.” the region.
This is demonstrated by the work of researchers from the University of Seville José Lázaro Amaro and Emilio Ramírez, professors in the Department of Graphic Engineering, in collaboration with the Remote Sensing Laboratory of the Technological University of Peru. To reach these conclusions, data from the period 2009 and 2020 were analyzed, in addition to studying 792 satellite images to verify the depth of the flooded area.
Flora and fauna in danger
The conclusion is the one already noted: the increase in temperatures combined with the decrease in precipitation seriously affects the marshes, which could disappear in a period of between 42 and 189 years. Added to this is the fact that the species of flora and fauna that inhabit this enclave, some of which are in danger of extinction, see their habitat areas reduced due to the loss of wetlands.
The study conducted a detailed analysis of sediment behavior and water flow in the area, revealing a significant decrease in water levels and sediment renewal capacity. Both factors are key to the health of this ecosystem.
The study highlights that, “without adequate intervention”, the reduction in the flooded area will continue to worsen, which could trigger an “ecological collapse” in one of the richest biodiversity areas in Europe. Thus, the researchers insist on the need to adopt urgent measures that include stricter management of water resources, restoration of affected areas and strengthening surveillance of illegal farming in the Doñana region. In fact, the measures implemented through the Doñana Pact between the central and Andalusian governments are moving in this direction.
Drawing of the evolution of marshes
In addition, they propose to continue using advanced technologies to improve the accuracy of long-term studies and thus facilitate decision-making based on scientific evidence. For this work, the technology used has allowed us to obtain high-precision data on the topography of the terrain, accurately reaching the areas most affected by erosion and changes in the flood zone. In addition, geographic information systems have facilitated the integration of these data with climate models that help predict the future evolution of marshes under different climate change scenarios.
The multidisciplinary team used cutting-edge geomatics techniques (advanced remote sensing, Lidar data, climate change models and Big Data analysis) integrated into a geographic information system (GIS) that allowed them to analyze, through a novel procedure, which were the main effects of climate change on the marshes between 2009 and 2020. To verify the depth of the flooded area, the researchers analyzed 792 satellite images.
