On the potential of basing an ecological typology of aquatic sediments on the nematode fauna: An example from the River Rhine

In Dutch river sediments nematodes can occur in high numbers; azoic seediments are as yet unknown. In aseries of samples takenj from the river Rhine and its estuaries, nematode density varied from 5.000 to 1.7 million per square metre, and about 50 genera were identified. Anoxic conditions appear to have less influence on the nematode abundance than the presence of ammonia. Based on nematode genera, an ecological typology of aquatic soils would appear to be feasible. The use of nematodes in environmental studies is discussed.