WaNuLCAS, a model of water, nutrient and light capture in agroforestry systems

Models of tree-soil-crop interactions in agroforestry should maintain a balance between dynamic processes and spatial patterns of interactions for common resources. We give an outline and discuss major assumptions underlying the WaNuLCAS model of water, nitrogen and light interactions in agroforestry systems. The model was developed to deal with a wide range of agroforestry systems: hedgerow intercropping on flat or sloping land, fallow-crop mosaics or isolated trees in parklands, with minimum parameter adjustments. Examples are presented for simulation runs of hedgerow intercropping systems at different hedgerow spacings and pruning regimes, a test of the safety-net function of deep tree roots, lateral interactions in crop-fallow mosaics and a first exploration for parkland systems with a circular geometry.

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