تصنيف بعض الترب العراقية باستخدام أحدى الطرائق المقترحة في التصنيف الهرمي التجميعي

الملخص EN

This study was conducted on some Iraqi soils in different regions of the country, representating various physiographic units, according to previous studies in soil survey and classification, in order to classify them numerically using some morphological, physical, and chemical characteristics.

Sixteen sites were elected in the following areas: Anbar, Mosul, Arbil, Sulaymaniyah, and Diyala.Soil individuals were classified numerically, using the method “Variable group algorithm” proposed by Fernández and Gómez (2008) to determine a uniquely type of valued tree and to compare the results with those of Ward method and USDA system.

The results showed the homogeneity of the two soil individuals of Diyala due to their similarity in some morphological characteristics such as, type of structure of B horizon, thickness of A horizon, Value and Chroma of A and B horizons.

Also it was observed their similarity in some chemical characteristics of organic matter content and cation exchange capacity of A horizon.

When comparing the physical characteristics, it was noted a similarity in the value of bulk density of B horizon and content of clay and silt of A horizon.These soil individuals were classified according to USDA system at subgroup level as Typic Calciargids.

The soil individual of Erbil was grouped with the soil individual of Anbar using the proposed method “Variable group algorithm”, while it was grouped with the soil individual of Mosul, using Ward method.

This difference in the classification of soil individuals was due to the fact that Ward method has aproblem of multi-solutions in numerical classification and because of the development of links between soil individuals during the fusion of hierarchical levels.

It is possible to avoid the development of such links by using the proposed method “Variable group algorithm” .