Heavy metal accumulation in oribatid mite species (Acari: Oribatida) in agroecosystems in Egypt

摘要

 The responses of oribatid communities to heavy metal contamination were studied. Concentration of cadmium, copper, lead and zinc in oribatid species along Ismailia water canal, Egypt was measured. Metal levels observed in both soil and irrigation water was compared with standard values of FAO and established permissible levels reported by different authors. Mean concentration of heavy metals determined in irrigation water were much above the recommended levels. Concentrations of all the metals (mg kg−1 dry weight) in the studied agricultural soil were below the permissible level standard. The comparison of mean concentrations of heavy metal in examined soil with that of typical uncontaminated soil in this area revealed that Ismailia water canal using in irrigation of agricultural soil has increased the levels of heavy metals. All studied oribatid species appeared to be accumulator's different amount of heavy metals characterized by the highest bioconcentration factors. The results of the study show that the abundance and structure of the soil oribatid communities in the sampling locations were not influenced by levels of heavy metals in the soil. They also show that the diversity index can be valuable tools for assessing the impact of pollutants on different species of oribatid mites