SHORT-TERM EFFECTS OF CADMIUM, COPPER, NICKEL AND ZINC ON SOIL NEMATODES FROM DIFFERENT FEEDING AND LIFE-HISTORY STRATEGY GROUPS

The effects of cadmium, copper, nickel and zinc on a nematode communit y were examined with a 'natural soil method'. Changes in the indigenou s nematode community structure were studied 1-2 weeks after the additi on of these metals (as sulphates) to soil collected from an agroecosys tem The soil was acid and only contained a moderate quantity of organi c matter as the main metal-binding constituent. As a result, its metal -binding capacity was rather low. The nematode community was found to be affected by increasing concentrations of Cu, Ni and Zn up to 1600 m g kg(-1), but not by Cd up to 160 mg kg(-1). EC(50) values for the red uction in population size of individual taxa showed a low intra-taxon variation for Cu, Ni and Zn. For these heavy metals, uptake and elimin ation processes as well as their final effect appear similar within th e same taxon. Omnivorous and predatory nematodes, known to be K-strate gists, were among the most sensitive taxa, and were already significan tly affected by 100 mg kg(-1) Cu, Ni or Zn added to the soil. The rela tive abundance of the different life-history groups and, to a lesser e xtent, the different feeding groups indicated pollution-induced change s in the soil community. However, neither classification predicts the acute effects of Cu, Ni and Zn on different nematode genera in an adeq uate way.