Gophers and grassland: a model of vegetation response to patchy soil disturbance

We present a computer model which simulates population processes and spatial patterning in response to gopher disturbance in an annual grassland community. The model includes the processes of seed production, dispersal, germination and seedling survival of four main grassland species. Runs show that soil disturbance by gophers affects both short-term spatial patterning and long-term species composition. The main determinant of species behaviour is their relative seed dispersal distances, and the model is relatively insensitive to initial species distribution or abundances. The model adequately simulated short-term community patterning, and provided predictions of long-term dynamics which can now be tested using longer-term field experiments.