THE VALUE OF INVESTING IN WETLANDS FOR NITROGEN ABATEMENT

The values of nitrogen abatement through measures involving investment in wetlands, sewage treatment plants and agriculture are calculated and compared. The analytical results show that the marginal value of investment in wetlands, including current and future utility, is likely to exceed that of other measures, due to two factors; the joint production of several environmental services and the net natural growth in the capacity to produce these services. The multifunctionality implies that, in addition to nitrogen abatement, other outputs such as buffering of water and biodiversity are produced jointly and the growth in wetlands, or the self organizing capacity, implies an increase in the supply of future outputs. Empirical results for Gotland an area with a high concentration of nitrate in the groundwater, suggest that the value of investment in wetlands could significantly exceed that of sewage treatment plants.