A model of the effects of cultivation on the vertical distribution of weed seeds within the soil.

Summary: A matrix model was constructed for the prediction of vertical seed movement within the soil. This was inserted into a model of the life-cycle of Alopecurus myosuroides in order to predict seed population dynamics. Parameter values were obtained from published sources and from a single field cultivation experiment using coloured plastic beads. In simulations, stability of vertical distribution was reached sooner under ploughing than under rigid tine cultivation. Stable distributions were very different for the two cultivation methods, being reached by damped oscillations in the case of ploughing and asymptotically in the case of rigid tine cultivation.