Catchments are spatially heterogeneous because of topography, soils, vegetation covers, and climate. These features shape the redistribution of water, energy, carbon, and nutrients in the landscape, influence hydrological connectivity, and create biogeochemical hotspots. This session explores how the spatial organization of landscapes, soil, and vegetation cover shapes coupled water, energy, carbon, and nutrient processes in heterogenous landscapes. We welcome observational, experimental, process-based modelling, and AI/ML-driven studies that identify the mechanisms organizing the spatial patterns of ecohydrological processes and feedbacks. Relevant topics include simulated and observed spatial patterns of water, carbon, and water quality and underlying mechanisms; hydrological connectivity and lateral transfers; the emergence of biogeochemical hotspots; propagation of local dynamics to catchment-scale carbon, nutrient, sediment, and pollution export; and spatially heterogeneous responses to climate change. We also encourage cross-catchments studies that compare contrasting landscapes, explicitly consider spatial heterogeneity, and larger-scale study that develop approaches for representing sub-catchment and sub-grid heterogeneity at regional and continental scales. This session potentially brings together hydrologists, biogeochemists, and modelers that improved the process understanding and modelling ability of coupled water, energy and elements in spatially heterogeneous catchments.