A STUDY OF THE RESIDUAL EFFECT OF PHOSPHORUS FERTILIZER IN SOIL

Abstract

The study was conducted on Brack-Ashkda agricultural project soil middle south of Libya to investigate the effect of soil depth (0-180 cm) and duration of soil use (January, April, July and October) on the presence of the level of available phosphorus as a residual effect of additions of phosphorus fertilizer to the soil. Results showed that the available phosphorus concentrations decreased with increasing soil depth (0-180 cm), they also showed that the concentrations decreased with increasing duration of use from January until October in all studied wells.