Soil forming factors: Their role in the formation of saline soils on the plains of Western and Central Ciscaucasia

Abstract

Relationships between the salinization of agrochernozems, agrochestnut soils, and textural carbonate agrozems on the plains and factors of soil formation in the Central and Western Ciscaucasia are considered. Among the studied factors are the following: parent rock, climate, relief, depth of groundwater table, and human activity (irrigation in particular, which is considered as one of the strongest anthropogenic impacts). In the territory of the objects studied, saline parent rocks predominate. They determine the potential (in autonomic landscapes) or actual (in subordinate landscapes) salinity of the main soils and their instability under intense use. The influence of climatic conditions can be registered only in the soil salinity over vast loess plains, where the agrochernozems are replaced by the agrochestnut soils. The influence of the meso- and microrelief on soil salinization is manifested in the regular transformation of soil cover structures in catenas. In the northeast of the loess plains, this phenomenon was expressed in the appearance of agrosolonetzic complexes on slopes and, then, in their predominance in subordinate positions. The response of the soil cover pattern to changes in the salt regime of the soils in catenas and its reconstruction under irrigation may serve as an indicator of trends in the dynamics of the soil cover related to human activities and climate fluctuations.