The objective of the study is to identify the effect of no-till technologies for processing agrochernozems on the heterogeneity of the compared soil layers in terms of protease and urease enzyme activity. The studies were carried out under the conditions of a production experiment laid out in the Shilinskoye agricultural production cooperative in the Krasnoyarsk forest-steppe located within the Chulym-Yenisei denudation plateau of the southwestern outskirts of Central Siberia (56°37' N and 93°12' E). The soil of the experimental plot was leached high-humus medium-deep light clayey chernozem on red-brown clay. The experimental soil was characterized by: humus content of 5.9 %, neutral reaction of the environment (pHH2O 6,8). The sum of absorbed bases was from 60 to 62 mg-eq/100 g of soil. In production crops, soil samples were taken three times during the vegetation season from the 0–5 and 5–20 cm layers using the snake method. The sample size was 15 individual samples. The norm, in accordance with the WMO regulations, was calculated for a 30-year period (1981–2010). The experimental design consisted of the following variants (processing methods): 1 – zero; 2 – minimum; 3 – moldboard (st). A significant differentiation of the studied agrochernozem layers was revealed when using minimum tillage technologies. Periods with a deficit of atmospheric moisture had a significant effect on the amount of proteolysis. An increase in moisture was accompanied by a decrease in proteolytic activity (r = –0.5 ... –0.63) when using surface disking, whereas under no-till conditions a direct effect of moisture on the level of hydrolysis of nitrogen-containing organic compounds was found (r = 0.61 ... 0.68). An increase in protease activity was accompanied by a significant decrease in difficult-to-hydrolyze nitrogen-containing compounds when using surface disking (r = –0.57 ... –0.71). During periods with excess moisture, significant differences in the level of urease activity were also found, mainly when using minimum tillage technology. The transformation of easily hydrolysable nitrogen-containing organic compounds was associated with the level of urease activity.
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