Season Dynamics of Pollution and Changes in Enzymatic Activity in Agricultural Soil near an Industrial Area

The aim of the study was to assess the ecological condition of soils in three regions in Armenia - Hrazdan, Gavar, and Martuni. It was shown that the soil samples from the three regions had low humus content in winter. However, in spring and summer, a significant increase in humus content was observed. The soils had a neutral pH of 7.11 to 7.83. The enzymes studied belong to the class of hydrolases (invertase and urease) and oxidoreductases (catalase). The urease activity was almost 2-3 times lower than invertase activity in all soil samples. During the winter-spring period, high catalase activity was observed in all soil samples. It was found that in Hrazdan and Martuni regions the enzyme activity was on average 62% higher than in soil samples from Gavar regions. The HMs distribution depends on seasonal variations and the wind rose in each region. In order to interpret the results, the given total contamination index (Zc) was compared, taking into account the cloud concentration of chemical elements. The value of the total index of pollution of arable soils by HMs near the Gavar region also had a moderately dangerous value.