The iron analysis of an arid-region soil showed an abundance of this element, yet a peach crop growing on the soil showed serious iron deficiency symptoms. What is a likely explanation? A soil with an...

The iron analysis of an arid-region soil showed an abundance of this element, yet a peach crop growing on the soil showed serious iron deficiency symptoms. What is a likely explanation?

A soil with an abundance of CaCO3 may have a pH no higher than about 8.3, while a nearby soil with high Na2CO3 content has a pH of 10.5. What is the primary reason for this difference?