Phosphorus in Tributaries to Lake Mälaren, Sweden: Analytical Fractions, Anthropogenic Contribution and Bioavailability

Abstract

Riverine phosphorus (P) concentration and P-transport to Lake Malaren, the third largest lake in Sweden, has been monitored for 35 years in 12 major tributaries. During a period of 15 months, complementary assessments of particulate P, suspended matter and dissolved reactive P were made. Particulate P comprised 64%, dissolved unreactive P 23% and dissolved reactive P 13% as flow-weighted means, with high seasonal variability. "Background" or "reference" P-transports in the streams were estimated by different methods and the anthropogenic contribution to transport was shown to be reduced over time. Potential algal availability of particulate P showed a mean availability of c. 45% for water draining arable and forested land, while the availability was higher for sewage discharge particulate P and algal P. Calculated total bioavailable P in tributaries was shown to equal reactive P measured on coarsely filtered water and it was indicated that the proportion of bioavailable P was higher during the period with high anthropogenic P-contribution than with a lower contribution.

Published in

AMBIO: A Journal of the Human Environment
2001, Volume: 30, number: 8, pages: 486-495

SLU Authors

• Persson, Gunnar

  • Department of Aquatic Sciences and Assessment, Swedish University of Agricultural Sciences
    

UKÄ Subject classification

Environmental Sciences
Oceanography, Hydrology, Water Resources


Publication identifier

DOI: https://doi.org/10.1579/0044-7447-30.8.486

Permanent link to this page (URI)

https://res.slu.se/id/publ/131604