Sauerstoffzufuhr zu den Wurzeln von Pflanzen aus Feuchtgebieten

Aquatic macrophytes or plants living in wet soils have to cope with oxygen shortage around their roots and rhizomes. These organs are not able to take up oxygen from the surrounding medium and have to rely internal oxygen supply through aerenchymatous spaces in the plants. The present study tries to elucidate the mechanism of oxygen supply to the roots of Acorus calamus, Iris pseudacorus, and Phragmites communis. Release of oxygen out of the roots could be of special importance because the species could contribute in the aeration of sewage sludges. Gas escape from the plants roots was found to be species specific: in Acorus and Phragmites rates of 1-2 ml of air h high -1 were calculated, whereas Iris was found to emit not more than 0.2 ml air h high -1 per plant. The reasons for the differences in diffusion are discussed.