The net present value (NPV) of downstream economic benefits of changes in water-yield (W) and salt-load (S) of mean annual river flow received by a lower catchment from an upper catchment are described as a 3-dimensional (NPV,W, S) surface, where dNPV/dW 0 and dNPV/d(S/W) 0. Upstream changes...

Dry land salinisation is a significant cause of land and water degradation in Australia. Changing land use from annual to perennial crops has been widely proposed as a means to reduce land degradation and increase the productivity of saline land. However, in many areas annual crops are...