Comparative analysis of heavy metals accumulation in the soil - plant system by the geo-accumulation index and transpiration rate of Zea mays L

The aim of work is the assessment of the effect of water deficiency in the soil, taking into account the characteristics of the migration of heavy metals in the soil - plant system using the example of mays ( Zea mays L . ). The samples studied grew in the coastal areas of the Debet, Shnogh and Araks rivers. The selection of plant material was carried out during the growing season at the test sites in clear dry weather. The analysis of the coastal soil and annual plant on the content of Mn, Cu, Co, Zn, Mo was performed using the “Thermo Scientific Niton XRF Portable Analyzer”. According of obtained results the coefficient of the geo-accumulation index was calculated, identifying the main migration characteristics of heavy metals in the soil - plant system. Drought tolerance was identified at the seedling stage by changing the growing conditions by changing of watering of the plot. Calculation of the intensity of transpiration revealed changes in the water balance in plants depending on the soil and climatic growing conditions. According to the obtained results, it is noted that with an increase in the geo-accumulation index of heavy metals in the soil, the plant shows a significant decrease in the intensity of transpiration. Thus, in the course of the experiments, it was established that samples of corn from the arid region of Hushakert had a low level of transpiration, compared with samples from the moderately humid region of Shnogh. Combining the results on the content of heavy metals in corn kernels with the intensity of transpiration made it possible to investigate the correlation between the cumulative ability of the studied chemical elements and the regulation of water balance in the plant in response to drought. Among the main factors contributing to the increase in the migration of heavy metals is the content of potassium and calcium in the plant sample.