Effet des métaux lourds (plomb, cuivre, zinc et cadmium) sur les caractéristiques biométriques et la synthèse de chlorophylle chez l’Atriplex canescens

Abstract

The problem of contaminatedsoilsisnow a major concern for emerging countries. Heavy metalssuch as lead, cadmium, copper and zinc cannotbebiodegraded and thereforepersist in the environment for long periods. Moreover, they are continuouslyadded to the soil by variousactivities: in agriculture by the application of sewagesludge or in the metallurgicalindustry. Theirpresence in soilsconsiderablyalters the floristic composition of the sites, the deterioration and disappearance of certain soilfunctions, allowing the installation of only a limitednumber of speciessupportingtheirtoxicity. The objective of ourworkis to study the effect of metallic stress induced by the application of four doses of copper (2000, 2500, 3000, 3500 ppm) on the one hand and four doses of lead, zinc and cadmium (2500, 5000, 7500, 10000 ppm) on the Atriplexcanecens, in semi-controlled conditions in the morphologicalparameters and Synthesis of chlorophyll. The tolerance of this plant wasstudied by the capacity of growth and yield. Phytoremediation is a new approach to decontaminating soils contaminated by the use of plants. Among the possible aspects of this method is phytoextraction based on the absorption and accumulation of the pollutant in the aerial parts. To be effective, it is necessary to have plants with significant adaptive potential and high biomass. The results obtainedshowedthat the effect of heavymetals varies from one parameter to another, itwasrecordedthat the metal stress did not carry out significantbiometric perturbations on the leaf area, length of the plant. And the study of Synthesis of chlorophyllbehavior of thisspecies shows a decrease in the concentration of Finally, itcanbeseenthat the Atriplex canecenspossesses an important resistance power againstheavymetals, whichallowedthisspecies to have a very important candidate for applyingphytoremediation.