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-'4000
 3


u 3000 -


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 0 -


0 2 4 6 8 10 12 14 16 18


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0 2 4 6 8 10 12 14 16 18


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39 80


S60


 40


0 2 4 6 8 10 12 14 16 18
 Age (years)


Figure 7.10.


0 2 4 6 8 10 12 14 16 18

 Age (years)


On the Left, Available Nutrients on a Mass Basis (mg Nutrient g- Soil)
and an Areal Basis (g Nutrient m'2 to a Depth of 20 cm, on the Right).
Ca (a,b), Mg (c,d), K (e,f), P (g,h) and Fe (i,j).


7-60


IN c- ^Rw I1 fcLi -Y r