Geochemical changes along infiltration-paths in a river-recharged aquifer in the 'Oderbruch' Region, eastern Germany

摘要

The Oderbruch, a region aside the river Oder, is Germany's largest enclosed river polder. As a result of intensive drainage activities since the 18th century, the river embankment is situated above the groundwater table within the polder. As a consequence, river water infiltrates permanently into the shallow confined aquifer. Chemical changes and reactions which occur when oxygenated river water enters into the anoxic aquifer are studied at an exemplary field site in the northern Oderbruch. The paper focuses on processes that control migration, dissolution and precipitation of the dominating iron and manganese species.