LINKFLOW, A WATER FLOW COMPUTER MODEL FOR WATER TABLE MANAGEMENT: PART 3. MODEL APPLICATION

摘要

A computer simulation model, LINKFLOW, was developed to compute the movement of water during various water table management practices. The development of the model and validation with field data has been covered in related articles (Havard et al., 1995a,b). This article describes the use of the model to investigate the effects of anisotropy and clay lenses on water table elevations during water table management. The first application considers subirrigation and drainage in an anisotropic soil, and the second describes effect of clay lenses on subirrigation and drainage system performance. The results of simulations suggest that water table management system performance can be significantly affected by soil anisotropy. Case simulations for subirrigation and drainage showed 18% and 25% reductions in water movement into and out of the drains respectively when the anisotropy of the soil increased from one to five. Further simulations showed the effect of clay lenses in the soil profile and how backfilling during installation would benefit subirrigation and drainage system performance. Backfilling around the drains for a soil with low permeability lenses showed 70% increase in water flow after 21 days of subirrigation.