Effectiveness of Land Application for Phosphorus Removal from Municipal Waste Water at Manteca, California1
- I. K. Iskandar and
- J. K. Syers2
The concentrations of dissolved inorganic phosphate (DIP) in soil solution collected at 0.8 and 1.6 m in soils which had received municipal waste water for 4 and 13 years ranged from 7.3 to 13.9 µg P/ml. In some cases, these concentrations were higher than that in the added waste water. Sorption studies Indicated that the ability of soils from the control site to remove added P from solution was low. Waste water addition caused a substantial decrease in the P sorption capacity of surface soils and a marked change in isotherm shape from a curvilinear to an essentially linear isotherm. Sorption capacity generally increased down the profile to 60 cm on the treated sites. Only a small proportion of the total P accumulated from waste water addition was in the organic form. Large amounts of P were extractable by 10−2M CaCl2, particularly in the upper 45 cm of the profiles receiving waste water. Although lack of crop removal of P and a high infiltration rate may be partly responsible for the poor performance of the Manteca system in terms of P removal from waste water, the very low P sorption capacity of the soil is regarded as the major factor.Please view the pdf by using the Full Text (PDF) link under 'View' to the left.
Copyright © . .