Sammanfattning

In coastal archipelago areas of the northern Baltic Sea, significantly higher phosphate concentrations (6.0±4.5μmol/l, mean±SD) were measured in water samples close to the sediment surface compared with those from 1m above the seafloor (1.6±2.0μmol/l). The results indicated notable phosphate release from sediments under the bottom water oxygen concentrations of up to 250μmol/l, especially in areas that had experienced recent temporal fluctuation between oxic and hypoxic/anoxic conditions. No single factor alone was found to control the elevated PO4-P concentrations in the near-bottom water. In addition to the oxygen in the water, the contents of potentially mobile phosphorus fractions, grain-size, the organic content at the sediment surface, and the water depth were all important factors controlling the internal loading of phosphorus. The complexity of this process needs to be accounted for in assessments of the internal loading of phosphorus and in potential mitigation plans.

Nyckelord

Baltic Sea; Internal loading; Sediment; Phosphorus fractions; Coastal zone; Hypoxia

Publicerad i

Marine Pollution Bulletin
2016, Volym: 108, nummer: 1-2, sidor: 77–86

Globala målen

Säkerställa tillgången till och en hållbar förvaltning av vatten och sanitet för alla
Bevara och nyttja haven och de marina resurserna på ett hållbart sätt för en hållbar utveckling


UKÄ forskningsämne

Geokemi
Ekologi


Publikationens identifierare

DOI: https://doi.org/10.1016/j.marpolbul.2016.04.059

Permanent länk till denna sida (URI)

https://res.slu.se/id/publ/78977