On the efficient use of a catchment's land and water resources: dryland salinization in Australia

This paper presents an investigation into the questions of long-term Pareto -optimal use of a catchment's land and water resources in the face of encro aching dryland salinization. An optimal control approach is adopted for pro blem analysis and translated into a dynamic catchment optimization model of salinity management. Model results suggest that, for the catchment under c onsideration, it is economically efficient to restrict soil salinization to a fraction of the area at risk, In the model. large-scale land-use changes , as required for maximization of the present value of the catchment, are i mplemented within a decade. Optimal control activities focus on the areas p otentially affected by salinity rather than the 'recharge areas' of the cat chment, suggesting that upstream recharge is largely Pareto irrelevant. Pig ovian and Coasean policy approaches are discussed under specific considerat ion of: (1) salinization as a stock externality; (2) the non-point source p ollution character of recharge: and (3) the isolation paradox surrounding s alinity management. (C) 2001 Elsevier Science B.V. All rights reserved.