Abstract
This study was carried out in an area which had been frequently exposed to sulphur ore dust for about five successive years (1985-1990). The hazard effect of sulphur ore dust was evaluated on the soil arthropod fauna at this region by Al-Assiuty, 1990. Since 1992 the source of dust had been stopped till now. Thus, the present investigation designed to evaluate the residual effect of sulphur ore dust after fifteen years since the stopping of the unloading operation of sulphur at this area. From November 2005 to October 2006, six plots of the soil each 25 m2 at Zawiet El-Bahr village on both banks of El-Rieyah El-Behary were sampled .Five random soil samples (10×10 cm to a depth of 10 cm) were collected from each plot. The obtained data were evaluated on the basis of relative abundance–frequency relationships, species diversity, stability, and similarity indices. The obtained results clearly showed that species diversity was increased in the eastern plots than the western plots. Stability was more obvious in plot G. Moreover, there are some new recorded mite species which were not recorded in the previous study. It could be concluded that the amount of sulphur residue in some plots represents as a stress factor on the population dynamic of oribatid mite species.

Key words: sulphur pollution, oribatida, abundance, species diversity