The biological activity of chernozems in the Central Caucasus Mountains (Terskii variant of altitudinal zonality), Kabardino-Balkaria

Some parameters of the biological activity (humus content; activity of hydrolytic enzymes invertase, phosphatase, urease; and the intensity of carbon dioxide emission) were studied in the chernozems of agrocenoses and native biogeocenoses in the foothills of the Caucasus Mountains representing the Terskii variant of the altitudinal zonality. The statistically significant differences were revealed between the relevant characteristics of the soils of the agrocenoses and of the native biogeocenoses. The integral index of the ecological–biological state of the soils was used to estimate changes in the biological activity of the arable chernozems. The 40–60% decrease of this index in the cultivated chernozems testified to their degradation with a decrease in fertility and the disturbance of ecological functions as compared to these characteristics in the virgin chernozems.