COMPARISON OF SOME DETACHABILITY INDICES IN RELATION TO SOIL ERODIBILITY ( KUSLE ) FOR CALCAREOUS SOILS

The objective of this study was to use some indices related to soil aggregate instead of soil erodibility factor KUSLE of the universal soil loss equation ( USLE ) for a selected calcareous soils. Twelve composite calcareous soil samples from 0 - 15 cm depth were collected from 12 different locations at Nineveh provenance. The selected soils were analyzed for five commonly used erodibility indices used for identify soil erodibility .These indices are ; Clay Aggregation Index (CAI ) , Clay Dispersion Ratio (CDR) , Clay Flocculation Index( CFI ), Dispersion ratio ( DR ), and Erosion Index of Bouyoucos ( EIB) The results indicated that there is a highly significant positive correlation ( r = 0.891**) between EIB and KUSLE in comparison to the other criteria which pointed a weak correlation Also ,the results show through variance analysis that the mean of the criterion EIB values ( 3.651 ) was very close to the mean of the KUSLE values ( 3.839 ). These results mean that EIB is more reliable index for prediction the soil erodibility in calcareous soils.