Soils of Agricultural Terraces on Clay Shales in the Mid-Mountain Zone of the Eastern Caucasus

The article considers the chemical properties and biological activity of soils of agricultural terraces on clay shales in the mid-mountain zone of the Eastern Caucasus. It is established that the area of terraced plots in the southern zone of Shale Dagestan is about 264 km2 of the territory. These soils are currently in a fallow state but represent a significant reserve of highly fertile erosion-resistant soils, the cultivation of which, unlike soils on consolidated rocks, is possible with the help of modern technology. The influence of slope exposure, steepness, terrace size, duration of the plowing period on the chemical properties and biological activity of soils has been studied. It is shown that for background soils outside the terracing zone, the slope exposure has a decisive influence. For terraced areas, the impact of exposure is less pronounced. The formation of a vertical terraced surface led to a change in the thermal regime, as a result of which the differences in chemical and microbiological properties of soils on the slopes of the northern and southern exposures became less pronounced. The leveling effect of terracing is most noticeable on relatively gentle slopes (12°–18°), where the width of the terraced canvas is greatest. On steep slopes (20°) with narrow terraces, the influence of slope exposure on soil properties remains. At the same time, factors such as the duration of soil functioning and the features of agricultural technology have no less significant impact on soil properties. The regularities of changes in soil properties within the body of any single terrace have been established. The most fertile area within one terrace is the instrument part, where the profile depth is greatest. As we approach the rear seam of the terrace, a natural decrease in a number of biological and chemical indicators is observed.