Comparison between some physical and chemical properties of mollisols and vertisols in Kurdistan region, Iraq

الملخص EN

This study was conducted to compare some soil physical and chemical properties of Mollisols and Vertisols in Kurdistan region, Iraq.

four pedons were chosen, two in each location.

Soil samples from horizons were taken.

Soil samples were air-dried, ground and sieved by (2 mm) sieve in order to be used for physical and chemical analyses.

the results indicated that the soil reaction (pH) was slightly alkaline (7.97- 8.35).

Electrical conductivity in all soil samples of both soil orders Vertisols, and Mollisols are low due to the leaching process by the rainfall additionally; these soil orders have well drainage conditions.

Organic matter content was concentrated at the surface horizon (Ap) in both study soil orders, both littering and humification processes are predominant in surface horizon and appear mollic epipedon in Mollisols.

the vertisols contained considerable organic matter content but less than Mollisols.

Vertisols contained more carbonates notably in the deep soil horizons.

Generally, there is an increase in total carbonates content with depth.

high cation exchange capacity (CEC) which decreased directly towards downward of soil profile.

CEC values in vertisols were relatively higher than in mollisols.

fluctuation in bulk density among soil horizons in Vertisols, whereas in Mollisols they were increased in bulk with depth.

clay content in vertisols increased with depth.