Some studies on calcium status in some salt affected soils of the Nile Delta in relation to their mineralogical composition [Egypt]
1988
Ali, R.A. (Tanta Univ., Kafr-El-Sheikh (Egypt). Faculty of Agriculture)
An investigation on the forms, status, release and distribution of calcium in some salt affected soils of the Nile Delta in relation to their mineralogical composition was done. Ten soil profiles in one transect extending from Messir at the south to Shalma at the north of Kafr El-Sheikh Governorate were collected for this purpose. The amounts of soluble, exchangeable, non-exchangeable (acid soluble and mineral) and total forms of calcium were found to decrease with depth. The large proportion of Ca +2 was found in the mineral form where its content varied from 98.9 to 128.7, 39.9 to 147.7 and from 41.0 to 144.6 meq/100g soil with respect to soil depth. The variations in the content of this form with depth may be attributed to the change in mineralogical composition and the layer age. The Ca-supplying power (Ca. S.P.) varied from layer to another, and has followed the same pattern of Ca+2 distribution with depth where it decreased with increasing the profile depth. The distribution of total Ca+2 abd Ca-bearing minerals percentages in the soil fractions was found in most cases to follow the sequence: Fine sand coarse silt very coarse silt fine + medium silt respectively.
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