Die Bodenkultur - Journal for Land Management, Food and Environment

G. Höflich, M. Tauschke, G. Schalitz, M. Joschko and A. Höhn:

Biological activity in flood polder of the river Oder

Summary

Of the different sites studied deeper located meadows with Pbalari sarundinacea and mud-filled-depressions were characterized by increased microbial activity and corresponding increased Ct -3, Nt - and soil nutrient contents compared to higher located meadows with Alopecuruspratensis. Increased contents of heavy metals did not have an effect. However, on sites with low clay contents easy deliverable heavy metals did affect different microbial activities negatively. In some cases positive correlations between shoot heavy metal content and the rhizosphere microflora were found. Collembola and mites were found mainly in higher located meadows with Alopecuruspratensis. On heavy metal contaminated sandy soils their numbers were low. The summer 1997 flood event reduced microbial activities, number of fungi, mycorrhizal colonization and numbers of collembola and mites dependent on the length of flooding on the different sites. In contrast colonization of bacteria and nitrification was not reduced. Key words:  flood polder, microbial activities, rhizosphere microorganisms, soil animals, heavy metals.