Unlike heavily humanized regions, where societal activity directly affects local biogeochemical cycles, high mountain areas—with their limited industrial and agricultural activity—serve as ideal locations for studying global-scale modifications of these cycles. High mountain environments are excellent territories for monitoring global change, as they belong to regions where atmospheric influences on nature are most clearly manifested. In fact, high-mountain aquatic ecosystems are considered “sensors” (or “sentinels”) of environmental change because they integrate signals from both natural and human-induced disturbances occurring in the atmosphere and within watersheds, ultimately influencing downstream ecology and chemistry. However, despite the evident and significant effects of global change on high mountain ecosystems, current knowledge remains severely limited by: i) the lack of studies and/or monitoring programs adopting an integrated landscape approach (one that considers processes operating along the atmosphere–soil–water continuum), ii) the scarcity of data collected at relevant spatial and temporal scales (e.g., high-frequency measurements or multi-basin sampling), and iii) the shortage of hydro-biogeochemical studies addressing the coupling and interactions between different biogeochemical elements (e.g., carbon and nitrogen), while also accounting for the magnitude of their mutual influences.
This project aims to implement a monitoring plan (or observation network) to analyze new evidence of directional responses of high mountain watersheds to environmental change and, consequently, to generate new knowledge about the modification of biogeochemical cycles at regional and global scales. From this general objective arise three specific objectives related to potential alterations of biogeochemical cycles in high mountain areas as a consequence of global change:
Objective 1. Assess how changes in hydrological regimes—caused by variations in snowmelt dynamics and extreme events (droughts or intense rainfall)—affect the transport and biogeochemistry of nutrients along the terrestrial–aquatic continuum in high mountain watersheds.
Objective 2. Evaluate how changes in the atmospheric system (air temperature, CO₂ availability, atmospheric deposition of assimilable inorganic compounds of carbon, nitrogen, and phosphorus, and the input of pollutants) influence the functioning of high mountain watersheds (including biogeochemical processes along the terrestrial–aquatic continuum).
Objective 3. Determine how land-use changes (e.g., upward shift of the treeline, changes in dominant terrestrial species) affect the transport and biogeochemical transformations of nutrients along the terrestrial–aquatic continuum in high mountain watersheds.