Joint International Conference on Long-term Experiments ...

Ca CO3(%) = AL − Cax2,5
10000
EDTE − CaxKA
Exch.-Ca (mg/100 g) =
75
The data obtained with mild complex forming solvents approach the quantities of
exchangeable Ca, moreover, they are informative in a mathematical sense. That means,
results obtained with EDTE-Ca signify the values of exchangeable Ca content.
With Mg, the same test has been performed with different solvents. Results are shown in
Table 2.
Table 2. Mg supply of 5 soil profiles measured by using different solutions for extraction
Samples pH(KCl) AL-Mg EDTE-Mg KCl-Mg Exch.-Mg H2O-Mg
Cs1 7.27 485 34.20 174 28.56 2.43
Cs2 7.31 747 26.00 105 23.84 1.54
Cs3 7.55 1194 37.20 138 25.53 1.84
Cs4 7.54 2123 108.00 335 60.50 5.51
Cs5 7.84 2867 226.00 572 86.88 12.40
KR1 7.05 645 70.30 349 45.62 4.25
KR2 7.20 931 57.10 332 55.66 2.25
KR3 7.32 1335 59.10 410 66.67 3.08
KR4 7.30 1920 80.00 526 80.83 4.16
KMR1 4.92 809 93.30 747 78.65 3.18
KMR2 5.03 934 94.50 938 99.83 3.20
KMR3 5.59 1068 104.00 1019 115.07 2.14
KMR4 6.38 837 92.60 758 80.22 1.84
KMR5 6.91 847 71.00 581 77.44 1.21
KH1 7.17 588 38.60 186 24.68 2.91
KH2 8.10 1793 111.00 252 54.21 5.42
KH3 8.39 1080 54.30 88 18.15 3.17
KH4 8.37 1020 63.60 79 19.36 3.70
KMH1 6.94 109 25.40 54 8.59 2.13
KMH2 7.11 61 18.20 39 8.59 1.63
KMH3 7.07 85 24.70 36 10.77 2.07
KMH4 7.49 53 14.10 33 7.62 2.38
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