Agriculture Reference
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Avarage of two
soil depths
3000
2000
Y = 1248.41 + 56.6337X - 0.4203X 2
1000
R 2 = 0.7736**.
0
10-20 cm
3000
2000
Y = 1347.17 + 58.6230X - 0.4696X 2
1000
R 2 = 0.7391**.
0
0-10 cm
3000
2000
Y = 1173.82 + 54.2814X - 0.3709X 2
1000
R 2 = 0.7956**.
0 0
20
40
60
80
Base saturation (%)
FIGURE 8.3 Relationship between base saturation and grain yield of dry bean. (From Fageria, N. K. 2008.
Commun. Soil Sci. Plant Anal. 39:845-857. With permission.)
In addition, in Brazil the lime rate is also determined on the basis of base saturation by using the
following formula (Fageria et al., 1990):
Lime rate (Mg ha −1 ) = [CEC (B 2 − B 1 )/TRNP] × df
where CEC is the cation exchange capacity or total exchangeable cations (Ca 2+ , Mg 2+ , K + , H + + Al 3+ )
in cmol c kg −1 , B 2 is the desired optimum base saturation, B 1 is the existing base saturation, TRNP is
the total relative neutralizing power of the liming material, and df is the depth factor, 1 for 20 cm
depth and 1.5 for 30 cm depth.
For Brazilian Oxisols, the desired optimum base saturation for most cereals is in the range of
50-60%, and for legumes it is in the range of 60-70% (Fageria et al., 1990). However, there may
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