Using a dune forest as a filtering ecosystem for water produced by a treatment plant - One decade of environmental assessment.

A dune forest in SW France composed of maritime pines was irrigated with treated wastewater for a decade in an experiment (including irrigated plots versus control plots) to evaluate the environmental impact of applying wastewater on the water table, soil properties, and plants. The amount of treated wastewater (1921 mm yr) applied was twice the annual precipitation. Nutrient inputs were also very high, particularly nitrogen (N: 539 kg-N ha yr), phosphorus (P: 102 kg-P ha yr), and calcium (Ca: 577 kg-Ca ha yr).