Phosphorus retention in a constructed wetland – the role of sediment accretion

A low-loaded constructed wetland was investigated with respect to phosphorus retention. Since the main long-term phosphorus retention mechanism is sedimentation and sediment accretion, the study focused on these processes. The purpose of the study was 1) to investigate how the calculated value of phosphorus retention (Pin – Pout), corresponded with the measured amount of phosphorus in the sediment, 2) to find out where in the wetland the phosphorus had accumulated, and in what form it was retained, and 3) to investigate the role of vegetation….

Contents

1 Abstract
2 Introduction
2.1 Background
2.1.1 Phosphorus retention
2.1.2 The role of vegetation
2.1.3 Mass balances
2.2 Aims and hypotheses
3 Materials and methods
3.1 Site description
3.2 Sediment sampling
3.3 Ground penetrating radar
3.4 Sediment analyses
3.4.1 Total phosphorus
3.4.2 Fractionation of organic phosphorus
3.4.3 Fractionation of inorganic phosphorus
3.5 Calculations for determining P retention and P content
3.6 Statistics
4 Results
4.1 Volume and density of the sediment
4.2 Phosphorus content and different forms of phosphorus
4.2.1 Total phosphorus
4.2.2 Phosphorus fractions
4.3 Phosphorus retention in Sˆdra Stene
5 Discussion
5.1 Phosphorus retention
5.2 Theoretical retention vs. measurements
5.3 Phosphorus fractions and their effect on retention
5.3.1 Methodological problems
5.4 Difference between inlet and outlet
5.4.1 The effect of sewage
5.5 Vegetation and its role in phosphorus retention
5.6 Conclusions
6 Acknowledgements
7 References

Author: Johannesson, Karin

Source: Linköping University

Download URL 2: Visit Now

Leave a Comment