Conclusions
Global challenges associated with climate change adaptation and mitigation underpin the need for an accurate understanding of factors influencing carbon cycling at whole catchment scales, to then inform effective management responses (Battin et al., 2023). A primary barrier is the lack of water quality and emissions data, which are also key to improving water management generally in river basins around the world. The coincident need for data collection at higher resolution should be addressed by capitalising on advances in distributed high-resolution sensor networks, combined with data analytic advances including ML methods. These systems provide an opportunity to overcome challenges including resource limitation, access to remote areas, inconsistent monitoring practices, and/or data collection with insufficient spatial/temporal resolution. Benefits from expanding the river carbon cycle process and emission understanding include closing knowledge gaps in international emissions inventories (IPCC, 2019) and facilitating more effective river catchment management.
While enhanced data collection and processing using in-situ sensors and other data products can fill large gaps, logistical and financial constraints will still limit comprehensive sampling of complex spatial river networks at high-resolution. Therefore, advanced data analytics methods need to be developed concurrently to allow for scaling-up from point estimates in space, for filling in data gaps in time-series (Segatto et al., 2023), and for predicting water quality parameters for which robust and reliable sensors do not yet exist (Ba-Alawi et al., 2023). DL methods have created significant opportunities and challenges in environmental research (Reichstein et al., 2019), although PINN and TL now provide a new basis to advance traditional DL methods. These methods are still in the research stage and significant investment will be needed to ensure confidence in water resource management applications. Nevertheless, rapid developments in data collection and analysis, with reducing costs present unprecedented new potential for monitoring and improving the status of freshwater systems worldwide. Capitalising on these technological advances quickly will be vital to address intersecting global crises in freshwater availability, water quality, biodiversity and climate change (Vörösmarty et al., 2010, Zhang et al., 2023) and maintain for future generations the array of critical ecosystem services that freshwaters provide to humanity.