The mechanism of arsenic behaviour in the soil-plant system and its interaction with biogenic macroelements of plants under conditions of toxic stress

Abstract

ABSTRACT The mobility of arsenic compounds in the soil-plant system and its interaction with biogenic macroelements K, P, Ca, Mg, Si, S, Na in plants under conditions of toxic stress have been studied. This is illustrated by the wheatgrass Elytrigia repens. It has been established that the root system is responsible for protecting the aerial part of wheatgrass from excess arsenic, and it is of great importance for phytostabilisation of arsenic pollution therefore indicating the increased tolerance of this plant. The intensity of As accumulation in plants depends on its speciation in the soil. Antagonism of the main essential elements (K, P) to the accumulation of As in wheatgrass shoots is observed. It can lead to disruption of metabolic processes in plant cells. It has been shown that changes in the K+/Na + values may lead to violation of osmotic processes in the aerial plant organs and contribute to their degradation not only under salt stress but also under the influence of higher concentrations of As in the plants. In areas intensively contaminated with arsenic, a decrease in the K/Na value in the above-ground organs of wheatgrass can be used as a criterion for the degree of phytotoxicity.