A simple tool to help decision making in infrastructure planning and management of phytotreatment ponds for the treatment of nitrogen-rich water

Abstract

In situ experimental studies were carried out aimed at the quantitative estimation of biological processes involved in nitrogen removal such as macro-algal assimilation and bacterial denitrification and their optimisation in two experimental phytotreatment ponds colonised by the macro-algae Ulva rigida in central Italy. Results from an in situ manipulative experiment estimate that Ulva carrying capacity defined as the macro-algal biomass in which the uptake of dissolved inorganic carbon (DIC) equals the production of oxygen (O2), was close to 300g·m-2 dry biomass (dw). At this carrying capacity the experimental assessment of Ulva growth rates and Ulva assimilation rates and their optimisation with use of a logistic model estimated that maximum inorganic nitrogen removal (~0.04 mol N·d-1·m-2) was attained when Ulva biomass reached 150 g dw·m-2 and growth rate was 0.1·d-1.

Authors

Categories