Nematode responses to biosolids incorporation in five soil types

The impact of biosolids on soil processes in five soils under pasture was assessed. Five biosolid treatments (control, dried pellets, compost, biosolids at 200 kg N/ha, and biosolids at 800 kg N/ha) were mixed in 0- to 10-cm-deep soil in lysimeters each year. Nematodes were sampled after 2 years. Many of the nematode populations and indices showed significant soil effects. Nematode responses to the range of biosolid amendments were similar across the five soils. Few populations showed an interaction between the type of amendment and the soil. The most marked response to amendment was that of bacterial-feeding Rhabditidae, in which populations were affected by the weight of the biosolid amendment. Nematode contribution to the soil processes in these soils was not adversely affected by the application of biosolids.