Water is continuously redistributed laterally across terrestrial landscapes and scales, from hillslopes and catchments to regional and continental river networks, through surface and subsurface pathways that connect groundwater, riparian zones, wetlands, floodplains, and rivers. These lateral hydrological connections redistribute water, energy, carbon, and nutrients across space, linking terrestrial and aquatic processes and influencing where carbon and nutrients are taken up, stored, mobilized, transformed, transported, or released.

This session focuses on biogeochemical responses to lateral water redistribution and how they change across spatial and temporal scales. We welcome contributions on how laterally redistributed water alters ecosystem productivity, respiration, methane cycling, and soil carbon and nutrient dynamics; how hydrological flow paths mobilize, transport, and transform carbon and nutrients; and how these effects interact, accumulate, or change across connected landscape positions and scales. We also welcome studies examining how these relationships vary with hydroclimate and landscape structure, and how they respond to environmental change.

Contributions may span hillslope, catchment, river-network, regional, continental, and global scales. We welcome field observations, experiments, remote sensing, synthesis studies, and modeling approaches, including process-based, data-driven, and hybrid models. The session aims to connect perspectives from terrestrial biogeochemistry, ecohydrology, critical zone and groundwater hydrology, and watershed science to better understand how the biogeochemical consequences of lateral water redistribution emerge and change across scales.