Heavy metals in the soil of Kalmykia arid territories

Abstract

In the composition of soils of the Republic of Kalmykia a large diversity of the gross content of heavy metals was found, which is explained by different genesis of top sediments and the leading role of fine particles in them. Several natural soil and geochemical provinces as well as technologically polluted territories were identified where an imbalance of chemical elements in food chains is observed. It shows promising use of the relationship between the gross amount of individual metals to study the genesis of soil-forming rocks and soils.The limits of the content of 23 elements were revealed, of which 5 elements are absent in the soil of the Republic of Kalmykiaor are within the sensitivity of the instruments. In the south of the Republic of Kalmykiaa soil and geochemical province with a high total As content was found. Its core is located in the southeastern part of the Black Lands. The arsenic content here ranges from 15 to 35 mg/kg. The province is polluted with oil. Besides, there is a uranium and phosphorite region, where, along with the phosphorus the arsenic was concentrated. The arsenic-rich rock destruction products were transferred to the neighboring plain and were part of sediments. However, toxicosis associated with a high content of arsenic was not observed in the described area, since soil As is immobile and its supply to food chains is limited. This can be judged by the number of elements in plant products: it remains environmentally friendly.