Nitrogen state of Haplic Chernozem of the European part of Southern Russia in the implementation of resource-saving technologies.

Background: The prolonged use of traditional moldboard ploughing often results in soil degradation and, ultimately, has an impact on national food security. Therefore, the implementation of resource-saving technologies (minimal and No-till) is a promising approach in the development of agriculture, especially in drought regions. The present study reports the results of long-term research on the effect of various tillage methods (moldboard ploughing, minimal tillage and No-till technique) on the nitrogen content of Haplic Chernozem of the European part of Southern Russia. The revealed regularities can be used as a theoretical basis for the effective use of resource-saving technologies, including No-till, in the zone of insufficient moisture.

Results: Long-term (59 years) cultivation of winter wheat using traditional moldboard ploughing has decreased the soil organic material (SOM) by 35% and total nitrogen by 32% in the soil. Minimization of tillage, in contrast, recovers the nitrogen potential of the soil in winter wheat agrocenoses. There is a statistically confirmed dependence of the content of SOM and total nitrogen on the tillage method of the upper soil horizon, with no significant effect of the tillage methods on intensity ammonification and nitrification. However, the content of nitrate-nitrogen during resource-saving tillage methods (22.8-24.4 mg kg ) was higher than that after ploughing (20.3 mg kg ) during all the years of the study, indicating the higher content of easily mineralizable nitrogen-containing compounds in the soil after minimal tillage.

Conclusion: The use of resource-saving tillage technologies under conditions of insufficient moisture stabilizes the nitrogen content in soil and can improve nitrogen nutrition of plants. © 2020 Society of Chemical Industry.