Modelling Lippia spread down flooding river systems.

Steven Ian Barry, Roslyn Hickson, Kate Stokes


Lippia (Phyla canescens) is an invasive, non-native plant prevalent in the Australian Murray--Darling river system that is considered detrimental in terms of lost agricultural production and environmental damage. This weed predominantly spreads as clonal fragments during floods and its growth rate is strongly related to soil moisture content. We use stage structured integro-difference equations to model the dispersal of reproductive units (clonal fragments and seeds) and explore the effects of flood length and height on spatial spread rates of the weed.

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