Moderately hazardous microelements in the soils of saline agrolandscapes of the Baraba plain

Abstract

When developing adaptive-landscape farming systems, special attention is paid to the study of the ecological, toxicological and sanitary-hygienic state of the territory used. This is especially important for saline agro-landscapes, which are widespread in the Barabinskaya plain (Baraba). The studies were conducted in the northeastern part of the Baraba within the Novosibirsk Region. The soils of the eluvial (meadow-chernozem), transit (chernozem-meadow), and accumulative (deep solonetz) zones of the catena were studied. The soils differed in physicochemical properties and microelement composition. In the soil profile from the eluvial to accumulative zone, alkalinity increased, humus content decreased, and the granulometric composition changed. These indicators affect the microelement composition. The content of moderately hazardous trace elements (hazard class 2): chromium (Cr), nickel (Ni), cobalt (Co) and molybdenum (Mo) were determined. It was found that the maximum content of total chromium falls on the profile of meadow-chernozem soil in the eluvial position. In the arable horizon there is less than 0.00001 mg/kg of mobile chromium, which does not fall within the detection range of the device. Some movement of mobile forms of chromium from the eluvial to accumulative position was noted. The maximum content of total nickel and cobalt was found in the profile of meadowchernozem soil, but it is in amounts well below the LOC. The total content of nickel and cobalt varies insignificantly across the soil profile, indicating their low mobility. The total content of Mo in soils is within the clarke range and is approximately the same over the entire depth. It was found that the content of moderately hazardous trace elements of nickel and cobalt in the soils of saline agro-landscapes of Baraba by catena is below the LOC and cannot be a hazard from the ecological-toxicological point of view. The content of total chromium and molybdenum is on the verge of the LOC and therefore, in certain cases, tension in the ecological and toxicological situation of the territory may arise. This should be taken into account in the agricultural use of saline agrolandscapes.