A Hydrometric Network for Estrela Geopark Territory

Abstract

Mountain habitats are usually unique and geographically confined, concentrating endemic and sensitive species. Therefore, these ecosystems are extremely vulnerable to the effects of climate changes. However, mountain streams usually reveal slow climate velocities, playing an important role as refugia for cold-water biodiversity. Consistent climate change predictions show that the Mediterranean region will be highly affected by increasing temperatures and decreasing precipitation. Severe droughts and associated natural hazards are the main concerns for the region, when regarding climate change scenarios. Recent works predict significant changes in water balance for the higher plateau of Serra da Estrela. As a result of the predicted increase of local mean temperature by 4˙C and the predicted decrease of the mean precipitation by 12%, mean streamflow is expected to decline by 15%, and streamflow during the snow-melting season is expected to drop by 40%. These effects will be even more severe, due to increasing water demands for economic activities under a dryer and hotter weather. Estrela Geopark is a high-value territory for Portuguese hydrography. The mountain range is the watershed for the three major basins of Portugal, and three important national rivers—the Alva, the Mondego and the Zêzere — spring in its higher plateau. The higher belt of Serra da Estrela also comprises a set of RAMSAR Wetlands of International Importance. Despite Estrela’s intrinsic hydrologic values, there are currently only 21 active hydrometric stations in the territory of 2.216km2, and only six of those are set above 1000m of elevation. Most of the active stations are set in artificial reservoirs, and are not suitable for evaluating climate change effects on natural highland water resources. In order to build a knowledge basis to understand climate change effects on Estrela Geopark habitats, and to guide local initiatives of adaptation to climate changes, we propose the foundation of a hydrometric network throughout the entire territory, but concentrating efforts on the most vulnerable and historically overlooked surface water ecosystems of the higher plateau of Serra da Estrela.