Effect of disturbances on trophic groups in soil nematode assemblages

In the passage “Effect of disturbances on trophic groups in soil nematode assemblages” the author Robert McSorley states that nematodes are abundant in soil ecosystems, where they have a variety of important function (Effect of disturbances). Plant parasites do not decompose the plants but they obtain food and energy directly from plant roots (effects of disturbances). Ni, Zn, Cu can reduce the number of omnivores and predators in soil. It makes short-term effects on them but if there are plants and if they can still feed they don’t go away. Soil fumigation is a way to get rid of nematodes. The bad thing about this is once the field is fumigated they will just move to some other part that has not been sprayed for them yet. The author is trying to tell us that there is no way to get rid of nematodes, we just slow them down. They cost so much for farmers and effects their crops greatly.
MCSORLEY, Robert. "Effect Of Disturbances On Trophic Groups In Soil Nematode Assemblages." Nematology 13.5 (2011): 553-559. Academic Search Premier. Web. 10 Oct. 2012