Most “eco-scapes” (by which I mean spatial distributions of ecosystems), including those in aquatic environments, are heterogeneous, a condition which can be indicative of a healthy, resilient diversity of habitats, or of fragmentation, stress and decay.  This heterogeneity is often conceptualised in terms of “patches” and “gaps”, amongst other spatial elements.  Interactions between the dynamics of the ambient medium (i.e. hydraulics and hydrodynamics in aquatic contexts) and patches and gaps in organism distributions are therefore central to determining ecosystems’ structure, functioning, possible future trajectories and responses to anthropogenic interventions.  This presentation will review work carried out over the past few years aimed at understanding these interactions and their implications, which has used physical modelling as its primary modus operandi.  The key finding of this work has been that the nature and density of gap-patch boundaries, and the relative locations of patches and patch-wakes are of overriding importance in determining how the organisms and hydraulics influence each other and interact with morphological, sedimentary, biogenic and biogeochemical aspects of their environments.  As well as discussing this finding using examples from studies of a range of freshwater and marine vegetation and benthic fauna, the presentation will also consider the challenges of applying physical modelling results to natural situations – particularly those challenges related to issues of scale – and the ways in which the wide range of societal and scientific drivers and applications for work in this area can provide a sense of the direction(s) in which it might best try to proceed.