Impact of Using Treated Wastewater for Irrigation on Soil Chemical Properties, Plant Growth and Forage Yield

Abstract

The objective of this study was to evaluate the impact of using
treated wastewater for irrigation under Khartoum State conditions. The
experimental treatments were treated wastewater, treated wastewater
alternating with River Nile water and River Nile water in combination
with three different tillage operations: harrowing, disc ploughing and
chisel ploughing. Replicated soil samples were taken from three depths:
0-20, 20-40 and 40-60 cm. 'Abu Sabein', a variety of forage sorghum
(Sorghum bicolor), was used as indicator plant. Chemical analysis
showed that the level of different constituents of treated wastewater
conform to FAO standards for irrigation water. Treated wastewater
significantly (P< 0.01) increased Ec, pH, OC, N, Na, Ca, Mg, K, Cl, Cu,
Zn, Fe, Mn, Pb, Co and P in the soil, followed by irrigation with treated
wastewater alternating with River Nile water and irrigation with River
Nile water. Similarly, highly significant (P< 0.01) effects were also
recorded for plant growth parameters and forage yield. Tillage operations
and depths showed significant (P< 0.01) effects on the distribution and
concentration of trace elements and nutrients in the soil. High transfer
factor was registered for Ca and Co, followed by P, K, Cu, Zn, Pb, Fe, Mn
and Na.