The following major actions have been implemented throughout the project:
Extensive field monitoring has been conducted, with a particular focus on the mapping of river networks and their temporal variability, as well as on the quantification of biogeochemical processes occurring in stream ecosystems. This resulted in the creation of a unique and comprehensive database of hydrological and biogeochemical variables.
Advanced hydrological, biogeochemical, and ecological models have been developed to simulate the spatio-temporal dynamics of river networks, incorporating interactions between hydrology, biogeochemistry, and ecosystem processes.
A comparative assessment of active stream length variations across multiple field sites has been performed, supporting the development of a novel theoretical framework for the interpretation and prediction of active length dynamics in non-perennial river systems.
The influence of microtopographic features on carbon dioxide emissions from riverbeds has been investigated through a combination of theoretical modelling and field observations, highlighting the role of fine-scale topography in controlling gas exchange.
Scaling laws have been formulated for the estimation of the fraction of non-perennial rivers at both regional and global levels, providing a basis for large-scale hydrological assessments in intermittent river systems.
New monitoring strategies have been designed and tested, alongside the development of methodologies for integrating heterogeneous datasets, enabling more robust and transferable data analyses.
The main results achieved over the course of the project include:
Testing and comparing multiple technologies for the mapping of river networks under various field and climatic conditions, including direct visual inspection, water presence sensors, satellite remote sensing, and thermal imaging from UAVs (drones). These comparative analyses enhanced the understanding of the strengths and limitations of each method.
The creation of a unique and high-resolution dataset capturing the temporal dynamics of stream networks across diverse catchments, characterized by varied climatic regimes, geological substrates, and land-use settings.
The development of stochastic models to describe and predict active stream length fluctuations and network reconfigurations, based on Bayesian networks and Directed Acyclic Graphs.
The identification of a universal hierarchical rule governing network expansion and contraction, whereby the most persistent stream segments consistently activate first.
The implementation of dedicated codes and simulation tools for modelling stream network dynamics, ecological interactions, and biogeochemical fluxes.
The proposal of a new methodology for spatial extrapolation of empirical data, allowing for information transfer between sites, gap-filling, and improved spatial representativeness of observations.
The generation of new global and regional estimates of the extent of non-perennial rivers.
The development of novel tools and indicators to assess the hydrological response of river systems to the spatio-temporal dynamics of their networks, supporting improved prediction of flow regimes and associated ecosystem impacts.
Dissemination and outreach:
The scientific results of the project have been widely disseminated through the publication of dozens of articles in international peer-reviewed journals, participation in national and international conferences, the organization of seminars and workshops, and the production of non-scientific outputs, such as popular articles, press releases, and interviews. All scientific outputs are freely available open access and are accessible via the project’s official websites.
