Answer to Question 1
Composition and physical characteristics of the parent material; climate (precipitation and temperature); vegetation; time; relief.
Answer to Question 2
Calcite forms in soil when there is a high concentration of calcium and carbonate ions in the soil solution. The high ion concentrations only occur when the evaporation of soil solution is high. In humid regions there is always enough water to keep concentrations low and the ions are flushed through the soil into deeper ground water. In places that are warm and dry, the soils get dried out, leaving behind a precipitate of calcite and other minerals like gypsum and halite.
A soil surface crust that includes nitrogen-fixing, soil-enriching cyanobacteria.
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Soil Erosion "تآكل التربة"
Soil Erosion "تآكل التربة"
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