Jb. Tome et Ar. Dechen, MICROWAVE OVEN-DRYING OF SOIL SAMPLES FOR CHEMICAL-TESTING IN BRAZIL, Communications in soil science and plant analysis, 26(3-4), 1995, pp. 515-529
In this experiment, we investigated the effect of microwave oven-dryin
g on soil samples for chemical tests. Samples were irradiated until th
ey achieved a constant weight and for one-half the time required. Two
other treatments were applied, air-drying at room temperature and forc
ed air oven-drying at 60 degrees C. Samples were analyzed for water pH
, 0.01M CaCl2 pH, organic carbon (C), Mehlich 1 and resin available ph
osphorus (P), exchangeable potassium (K) and calcium (Ca) plus magnesi
um (Mg), and potential acidity [1N calcium acetate (pH 7.0) extractabl
e hydrogen (H) plus aluminum (A1)]. The results showed that microwave-
drying can induce erroneous interpretations of the ''fertility status'
' of the soil, thereby affecting fertilizer recommendations and lime r
equirement determinations.