Monitoring Ecohydrological Variables in a Peri-Urban Forest and a Non-glacial High-Elevation Grassland Representing Possible Future Conditions in the Alps

Mountain environments often suffer from a scarcity of comprehensive environmental data that are the starting point for a better understanding of ecohydrological dynamics and for the validation, or improved conceptualization, of hydrological and land surface models. Recognizing the critical importance of understanding these environments to address the challenges of water resource management under unsettling future climate scenarios, research efforts are underway to address the lack of information. This study focuses on the comprehensive monitoring of ecohydrological variables within two contrasting catchments in Northwestern Italy. The first catchment (Colle del Nivolet, Aosta Valley) is monitored with a station located in a non-glacial high-elevation (2555 m a.s.l.) grassland. The second catchment (Bussoleno Grangia dell’Alpe) is monitored through a station at 650 m a.s.l. in a peri-urban forest. The research employs advanced monitoring techniques such as cosmic ray probes, environmental tracers (such as stable water isotopes in vegetation, soil and streamwater), and the eddy-covariance setup for atmospheric monitoring. In this regard, micrometeorological instruments have been installed on a 5 m-high mast (grassland site) and a 25 m-high mast (forest site). The previously mentioned monitoring techniques lead to the investigation of key ecohydrological variables such as energy, water vapor and carbon dioxide fluxes, 3D wind speed, soil moisture, soil matric potential, 4-component solar radiation, snow water equivalent, and the water isotope content whose integration provides necessary insights of hydrological and ecohydrological processes occurring from the plot to the catchment scale. Continuous monitoring over several years covering a wide range of wetness conditions, including the (probably) worst drought in the past two centuries in Northern Italy, lays the foundations for the identification of trends, anomalies, and potential shifts in these variables, thus providing a picture of the ecosystems' adaptive capacities in the face of evolving environmental conditions.