Assessment of the current physical and chemical status of the alluvial soils of the Volga-Akhtuba floodplain and the Volga delta

Abstract

The article dwells upon the study of the current physico-chemical status of the alluvial dark-humus soils of the floodplain hayfields of the Volga-Akhtuba floodplain and the Volga delta. Alluvial soils are formed in special semiaquatic conditions; they are the result of alluvial and soil-forming processes. Considered to be dynamic both in natural and anthropogenic conditions. They have subordinate status and remain to be barriers and accumulators of various chemical elements while performing a sanitary and hygienic role in floodplain and delta ecosystems. Due to the increased anthropogenic load on alluvial soils, the study of their physico-chemical status, which affects the migration of chemical elements, becomes particularly significant. The alluvial soils of the Volga-Akhtuba floodplain and the Volga delta are characterized by a polynomial profile in which soil horizons of varying development degrees alternate with river sediments. The soils of the studied landscapes are characterized by good agrophysical and relatively satisfactory agrochemical condition. It was found that bunds on the territory of the delta as well as in the floodplain have negative impact on the physico-chemical status of alluvial soils and actively develop secondary salinization. The focus is on the agrochemical properties of alluvial dark-humus soils, particularly on the content of humus and nutrients. According to the granulometric composition, the studied soils are medium and heavy loamy, they have a good supply of productive moisture. In the soils of the Southeastern part of the floodplain, the processes of salinization, dehumification and alkalization are most present.