Comparison of Mehlich 3, Mehlich 1, ammonium bicarbonate-DTPA, 1.0M acetate, and 0.2 M ammonium chloride for extraction of calcium, magnesium, phosphorus and potassium for a wide range of soils
Communications in Soil Science and Plant Analysis 24(7-8): 603-612
ISSN/ISBN: 0010-3624 Accession: 002328003
In a wide range of soils, from citrus groves in Florida, representing 21 soil series with pH ranging from 3.57 to 7.28, Ca or Mg contents extractable by Mehlich 3 (M3), Mehlich 1 (M1), ammonium acetate (AA) and NH4Cl were strongly correlated with soil pH (rsuperscript 2 = 0.381-0.482). Weak but significant correlations were also found between ammonium bicarbonate DTPA/(AB-DTPA) extractable Ca or Mg and soil pH (rsuperscript 2 = 0.235-0.278). There was a weak correlation between soil pH and extractable K (rsuperscript 2 = <0.131) for M1 and NH4Cl Ca, Mg and K extractable by M3 were significantly correlated with those by M1, AA or NH4Cl extractants. M3 extractable P was correlated only with M1-P (rsuperscript 2 = 0.654).