Paper Title
Using Mathematical Criteria for Specifying Soil Development in Aridisols and Mollisols in Kurdistan Region, Iraq

Abstract
The study area was located in the northern Iraq and Kurdistan region that including Mollisols, and Aridisols. Six pedons were dug and nineteen soil samples were taken. The ratio of fine clay / total clay, fine clay / coarse clay, and the ratio of clay in B horizon/clay in A horizon indicated soil development slowly in Aridisols. Pedon (JA1) was less development comparison with both pedons (KA2 and BA3). The ratio of active carbonate / total carbonate in pedon (JA1) was higher than it in both other pedons (KA2 and BA3) and the C: N ratio concurrently increased also, this increase in the C: N ratio means less humification and more litter accumulation. Apart from the slow development Mollisols but contain a considerable amount of total clay. The C: N ratio in Mollisols indicated accumulation of organic matter and dominance of littering and humification process that indicated to increase development in Mollisols. The most important conclusion of this study proves that cannot be specifying soil development as an absolute case and depending just on one criterion without taking into account other criteria. Keyword - Soil Development, Total Carbonate, Mathematical Criteria, Clay, Mollisols, Aridisols