Interplay of lake motions and processes affecting horizontal transport in a range of water bodies

Knowledge of the distribution of biochemical material within a lake or freshwater reservoir is of upmost importance to the resource managers and stakeholders. The impact of horizontal advection and dispersion on patch dynamics of aquatic species is also an active area of scientific interest. Horizontal transport in lakes, especially horizontal dispersion, is mostly addressed at the basin-scale in the literature, and there is a need to characterise and quantify the effect of local processes - i.e. as has been done for vertical transport. The objective of this study was thus: from observations and hydrodynamic modelling of three water bodies, determine the contribution of a range of lake motions to horizontal transport. The study encompassed sites with different spatial scales, basin shape, external forcing and internal structure. Horizontal motion and transport associated with partial upwelling events were investigated in a narrow reservoir, showing effective horizontal transport due to gravitational motion set up by localised vertical mixing.