Dynamics of zinc content in soil of the reference sites of the lipetsk region

Abstract

Due to the data obtained from agrochemical research on the tilth-top soil of the reference sites, the zinc content was low. During the 20-year research it has been decreasing. In 1994, this indicator was 0.92 mg/kg in 16 sites, in 2015 it was 0.42. This regularity was observed in all sited during all the periods of the research. The research on the zinc content in gross forms in the soil of reference sites and deposits showed that during the whole period there was a decrease both in upper and lower layers of the soil profile. In all studied arable areas and deposits the highest zinc content was in the upper layers (0-20). In 1999, the gross content of zinc in the layer of 0 to 20 cm was 42.9 mg/kg, in the layer of 40-60 cm - 42,7 mg/kg, in the layer of 80-100 cm - 41.9 mg/kg, in 2014 it was 34.5, 30,7,25.4 mg/kg, respectively. The zinc content was less in the top soil than in the arable land. Thus, the study revealed a low content of available zinc in the tilth-top soil. There was a further decrease both in arable and in the underlying layers of the soil profile in the reference sites. Zinc content in primary and secondary products varied from crop to crop and did not exceed MAC.