EFFECT OF TREATED WASTEWATER APPLICATION ON SOIL CHARACTERISTICS AT ABU-RAWASH AND ARAB ABU SAED AREAS, EGYPT

Abstract

: Abu- Rawash and Arab Abu Saed Sites are located at the western and southern parts of Giza Governorate, Egypt respectively. They represent two sites irrigated with sewage effluent. Twelve soil profiles as well as eleven water samples were collected by using Global Position System (GPS). Soil samples were obtained to represent two depths: i.e. surface (0-30 cm) and sub-surface (30-60 cm). Water samples were collected at the vicinity of sampled soil. Physical and chemical characteristics of the collected 24 soil samples and 11 water samples were determined. Cluster analysis was performed on effluent and surface soil analytical data separately. Spatial distribution based on GIS images was produced using the inverse distance weighted (IDW) feature in Arc-GIS 10.4 software. According to ECw and SAR values, the water sources in two sites are of a reasonable quality that can be used for irrigation with few restrictions . It is noteworthy that, although most macro, micro-nutrients and ionic contents are relatively high in the two sites as compared to the fresh irrigation water, yet their levels are still within the recommended maximum limits of Egyptian code and world water. Cluster analysis (CA) of the effluents’ analytical data (excluding TDS) at each domain is depicted for Abu Rawash and Arab Abu Saed. For both areas, two predominant clusters were present. Cluster (1) combine elements: P, Fe, Mn, Zn, Cu, Cd, Cr, Ni, B and Pb. This interrelationship may infer that these elements were of a similar origin not natural. The cluster of Abu Rawash soils K + , Zn -- , CaCO 3 ,Cu and pH infer to K, Zn and Cu elements are related to CaCO 3 ; while, N, SO 4-- , Cl - ,HCO 3- , Na + , Ca ++ , Mg ++ , silt, sand ,depth and SP refer to the relation of soluble ions with soil characteristics. In Arab Abu Saed cluster soils Zn, Mn, clay, pH, and SAR infer to Zn and Mn elements are related to clay; However, SO 4-- , Cl - , Na + , Ca ++ , Mg ++ , HCO 3- refer to the relation of soluble ions with soil characteristics. Also, N, P, K, Fe, Zn and Mn are more associated with the proportions of silt, clay, CaCO 3 and, to a lesser extent, with the SAR and pH value. The soils in Abu Rawash area are older than the soils in Arab Abu Saed area, therefore soil dismantling event in Abu Rawash area due to frequent service processes. In Abu Rawash site, the spatial distribution pattern of the available of N, K, Mn, Cu, B, Co, Cr, Ni and Pb are generally similar, with elevated levels in the eastern side which may be affected by El-Muhit drain . In Arab Abu Saed site, the higher values of major elements (P, Fe, Zn, Cd, Cr, Ni and Pb) were concentrated mostly in the northern and north western side near the sources of effluent. These observations clearly demonstrated that near El-Saff drain plays a key role in the pollutants distribution in this areas .