Monitoring of soil pollution in the area affected by the production of phosphorus fertilizers

Abstract

The soils of the Kingiseppsky district of the Leningrad region were studied in the zone of influence of the production of phosphorus fertilizers at a distance of up to 5 km from the pollution source. In 43 soil samples, the total content and mobile forms of heavy metals, sulfur, fluorine, phosphorus, calcium, magnesium, carbon, actual and potential acidity were determined. Three types of territories have been identified – conditionally background, reclaimed quarries, large man-made objects - phosphogypsum dumps and tailings. Exceedances of the MPC of mobile forms of elements in the conditionally background territory were revealed for copper, and for man-made objects - for manganese, copper, lead, nickel and zinc. The maximum gross content (in mg/kg) of barium (877), cadmium (1.5), copper (63), nickel (105), strontium (17,000), vanadium (218), zinc (107), antimony (1 ,86), chromium (103), phosphorus (13904), sulfur (1100) are typical for soils of technogenic objects. Barium, cobalt, manganese, lead, scandium, iron are evenly distributed over the study area. The average gross content of barium is 530, cadmium - 0.19, cobalt - 6, chromium - 32, copper - 14, iron - 22834, nickel - 16, manganese - 510, lead - 21, antimony - 0.36, scandium - 7 , vanadium - 48, zinc - 49, strontium - 627 mg/kg. At the same time, barium and lead are characterized by low variation; medium - cobalt, chromium, iron, manganese, scandium, zinc; high - copper, nickel, antimony, vanadium; abnormally high - cadmium and strontium. Medium mobility is characteristic of barium, increased mobility is characteristic of lead and nickel, manganese, copper and zinc are characterized by high mobility. Concentration coefficients of chemical elements in the soils of large technogenic objects calculated from the zonal background for podzolic soils: V(1.03); Zn(1,2); Ni(1,2); Cu(1.4); Sb(1.5); Pb(1.7); F(7,3); Ba(8); P(11.6); Sr(12.9); Ca(38.6). On the conditionally background territory: Zn (1,2); P(1,3); pb(2,2); F(1.5); Ba(12). Significant soil pollution and a decrease in the amount of organic matter are observed at man-made objects. In the conditionally background area, the amount and concentration of pollutants are decreasing. It is necessary to constantly monitor the ecological state of soils, especially their chemical pollution.