ABSTRACT
In modern agriculture, large quantities of pesticides have been used to control pests and weeds and thus increase food production. However, their wide and extensive application and a potential risk that they pose to the soil ecosystem raise a number of environmental concerns. One of the problems that should be addressed is the impact of pesticides on nontarget soil microorganisms, resulting in the perceptible changes of soil properties and the alterations of soil equilibrium for shorter or longer periods. It is well recognized that balance in the soil environment largely depends on the activity of the microorganisms, since they play an essential role in many soil biological processes, including nitrogen transformation, organic matter decomposition, and nutrient release and their availability, as well as stabilization of the soil structure (Edwards and Bater 1990).
