Document Type : Original Article

Authors

• Mohsen Bagheri ¹
• Norair Toomanian ²

¹ Soil and Water Research Institute

² Soil and Water Research Center, Agricultural Research, Education and Extension Organization (AREEO), Isfahan, Iran

Abstract

Abstract
Soils are the outermost layer of the earth's crust, and they are closely interrelated with the formation of the land on which they are formed and developed. Therefore, any change in the geomorphic processes affects the soil-forming processes. "Soil geomorphology" is an assessment of the genetic relationships between soils and landforms. Although the relationships between landforms and soils have been investigated by researchers, a quantitative evaluation of the relationship between soil and geomorphic surface has been less considered. However, the soil-geomorphology relationship is a two-way relationship, and a question arises here is that how an observed soil can indicate geomorphic surfaces or landforms? Accordingly, the current research tries to examine this issue with the use of statistics and conditional probability. For this purpose, the geomorphic units of the central region of Isfahan were delineated using geopedology approach (Zinck method) and 344 soil profiles were analyzed, and the conditional probability of the existence of each geomorphic unit was obtained on condition of observation of different soils. The findings quantitatively showed that there is a strong and close relationship between soil development and formation and the geomorphic condition, so that some soils can be found only in certain geomorphic unit. In other words, the soil is an indicator/unique soil for the geomorphic unit. Due to the similar relationship between the geomorphical levels and the soil taxonomical levels, the diversity increased as the taxonomical levels increased from orders to the families. Also, the findings showed slightly in the study area that the effect of "landforms and topography" on the development and formation of soils is more than parent material.

Keywords

• Conditional probability
• Geopedology
• Soil mapping