Figure 2.

Conceptual diagram of environmental filters determining the presence and absence of species in salinized rivers. The fauna that inhabit salinized rivers will be influenced by the ability of regional riverine fauna to survive and complete their life cycles in the new salinity, perhaps following adaption. The ability of species from existing saline environments to disperse to and tolerate riverine environments (perhaps following adaption) will also be important. Red straight arrows indicate species movement through filters, the reduced size of arrows indicates that some species did not pass the filters (shown by circles). Blue curved arrows indicate species that indirectly pass through a filter after rapid adaptation. The word ‘interactions’ refers to ecological interactions between organisms, e.g. competition and predation. The shapes in the blue squares indicate different species, with their sizes in the final square indicating relative population size.