ACCUMULATION AND DOWNWARD TRANSPORT OF PHOSPHORUS IN FLORIDA SOILS AND RELATIONSHIP TO WATER QUALITY

Accumulation of phosphorus (P) for Florida soils under citrus production may have an impact on groundwater and nearby streams and lakes. Six extracting solutions including Mehlich3, Bray1, double-acid, ammonium bicarbonate-DTPA (ABDTPA), neutral NH4OAc, and water were used to investigate P accumulation for 44 surface soils. The samples have been collected from old groves in 7 major citrus production counties in Florida. The results indicated P accumulation in most soils investigated. Either Mehlich3, Bray1, or double-acid was a good test to evaluate P accumulation. The average amount of P extracted was 121, 97, and 101 mg kg 21 soil for Mehlich3, Bray1,