Modeling the Impact of Potential Wetlands on Phosphorus Retention in a Swedish Catchment

• Published in: Ambio Vol. 34; no. 7; pp. 544 - 551
• Main Authors: Tonderski, Karin S., Arheimer, Berit, Pers, Charlotta B.
• Format: Journal Article
• Language: English
• Published: Sweden Royal Swedish Academy of Sciences 01.11.2005; Springer Nature B.V
• Subjects: Agricultural watersheds; Aquatic plants; Arable land; Artificial wetlands; Catchment scale; Catchments; Computer Simulation; Constructed wetlands; Creeks & streams; Effects; Environment; Freshwater; Geography; Hydraulics; Load; Modeling; Models, Theoretical; Nitrogen; Outlets; Phosphorus; Phosphorus - analysis; Phosphorus content; Phosphorus removal; Pollution control; River networks; Rivers - chemistry; Studies; Subwatersheds; Sweden; Total suspended solids; Vegetation; Water flow; Water Pollutants, Chemical - analysis; Water pollution; Water quality; Watersheds; Wetlands; Sweden; Sweden, Roennea R
• ISSN: 0044-7447; 1654-7209; 1654-7209
• DOI: 10.1579/0044-7447-34.7.544

In southern Sweden, wetlands are constructed to remove nitrogen (N) in agricultural catchments. The possible effects of such wetlands on riverine phosphorus (P) were also estimated using input–output data from three well-monitored wetlands. This was done to formulate a simple model for removal of P that is dependent on inflow characteristics. Next, the N- and P-reducing effects of wetlands were modeled on a catchment scale (1900 km2) using the HBV-NP model and various assumptions about the wetland area and location. All three wetlands functioned as sinks for total P (tot-P) and for total suspended solids (TSS) with a removal of 10% to 31% and 28% to 50%, respectively. Mean P-removal rates of 17–49 kg ha−1 yr−1 were well simulated with the model. Catchment scale simulations indicated that wetlands were more efficient (in percentage of load) as traps for P than for N and that this may motivate the construction of wetlands for P removal far upstream from the catchment outlet.