Tightly intertwined: Waterscapes prompt urgent reconsideration of aquatic insects and their role in agricultural landscapes.

In landscape ecology, the waterscape refers to permanent or temporary, running or stagnant surface waters within a terrestrial area. Across ecosystem boundaries, aquatic organisms and nutrients can reach terrestrial ecosystems, as formalised by the meta-ecosystem theory. Recent studies on aquatic insects emerging from temperate streams suggest that the extent of their biomass and fluxes across agricultural landscapes may have been neglected until now. Following a conceptual and empirical approach, we presently discuss how the temporal dynamics of floods coupled with the emergence and aerial fluxes of aquatic insects suggests that the waterscape can largely overlap the landscape. Depending on the season, various species and biomasses of aquatic insects could interact with the receiving terrestrial ecosystems and ultimately support vital ecosystem services and functions such as pollination, soil fertilisation, and control of crop pests or facilitation of their natural enemies. In the current context of a global collapse of terrestrial insect populations, we call for an urgent research effort to include the temporal dimension of waterscapes into landscape models to estimate the fluxes of insects emerging from all kinds of aquatic ecosystems and quantify their role in the functioning of terrestrial ecosystems in agricultural landscapes.