Some observations on the occurrence of phosphorus in recent sediments from western Europe

Near shore and fluvial sediments from the Netherlands and surrounding areas are composed of org-P, FeAl phosphorus and Ca-phosphorus. In marine sediments the org-P constitutes about 25% of the total phosphorus in the sediments. In Lake Yssel higher concentrations of organic phosphorus are found, whereas in fluvial sediments concentrations tend to be lower. The phosphorus in the highly contaminated river Rhine is mainly present as FeAl phosphorus. In sediments from the Dollard area (Wadden Sea), a diagenetic recycling of phosphorus takes place which results in high concentrations of phosphorus in the oxidised surface layer of the sediment. The phosphorus in this layer becomes reprecipitated as FeAl phosphate. The oxidised surface layer may act as a chemical barrier against the upward flow of some metals and nutrients from the interstitial water to the surface waters.