DOI: https://doi.org/10.36719/2707-1146/63/33-40
Ecological Assessment of Changes in Total Nitrogen in the Soil Profile Under Wheat Cultivation in Irrigated Conditions
Ali Baghirli 
Abstract. This study was conducted on the basis of soil samples taken from the irrigated wheat field located at the Terter regional experimental station of the Agricultural Scientific Research Institute of the Ministry of Agriculture of the Republic of Azerbaijan. The main objective of the study was to determine the distribution characteristics of total nitrogen (Nᵗ) in the soil profile at different depth layers and to evaluate these indicators from an ecological perspective. According to the results of laboratory analyses, the total nitrogen content was 0.108% in the 0–21 cm layer, 0.105% in the 21–50 cm layer, 0.100% in the 50–88 cm layer, and 0.095% at a depth of 88–122 cm. The results show that nitrogen in the soil profile is higher in the surface layers and gradually decreases with increasing depth. This decrease is mainly due to the greater accumulation of organic matter in the upper layers and the intensive mineralization processes in the surface layers as a result of the activity of microorganisms. At the same time, the movement of nitrogen in the form of nitrate to the lower layers through leaching and infiltration processes under irrigation conditions also affected this distribution. Such distribution of nitrogen in the soil profile is of great importance from an agronomic and ecological point of view. The results of the study indicate that scientifically based application of nitrogen fertilizers, especially fractional application, and optimization of irrigation regime are essential for ecologically sustainable wheat production.
Keywords: irrigation, wheat, soil profile, total nitrogen, mineral fertilizer, ecological risks