SOIL QUALITY ASSESSMENT AND PHYTOACCUMULATION POTENTIALS OF SELECTED EDIBLE VEGETABLES AROUND NTIGHA SOLID WASTE DUMP, ABIA STATE, NIGERIA

The present study evaluated the impact of open solid waste dumping on soil physicochemical characteristics, enzyme activities, soil heavy metals and bioavailability of these metals in selected edible vegetables. Twenty-six soil samples were collected from 13 different points. The considered points were center of the dumpsite (DC), 4 meters away east (E1), west (W1), north (N1), and south (S1) from the center of the dumpsite; and 8 meters away east (E2), west (W2), north (N2) and south (S2) from the center of the dumpsite. The controls were taken 100 meters away from the dumpsite center east (E3), west (W3), north (N3), and south (S3). Soil samples were collected at the depth of 0-45cm and 46-90cm at each point. Results obtained showed the physicochemical and enzyme activities of the center of the dumpsite (DC) were affected when compared to other points considered in this study. Significant differences between soil depths were also observed. Soil heavy metals also showed significant increase in dumpsite compared to control soils (P<0.05). Phytoavailability of the heavy metals studied showed that vegetables grown around Ntigha dumpsite accumulated significant level of the metals compared to their control counterparts (P<0.05). This study has revealed that open pit disposal of solid waste increased the phytoaccumulation potentials of edible vegetables grown around the dumpsite. Hence proper waste disposal method is advocated so as to prevent bioaccumulation of these heavy metals in human food chain