The regularities of heavy metals and arsenic accumulation in the vegetation of riverside depending on the level of technogenic load

The regularities of heavy metals (Fe, Cu, Zn, Cd, Pb) and arsenic accumulation in various types of aquatic vegetation have been studied, depending on the season and the levels of pollution of the Srepok River (Vietnam). It has been found that the concentrations of Fe, Cu, Zn, As, Cd and Pb in all studied areas of the river in the roots of water hyacinth and common reed were higher than those in the stems. It has been shown that the content of toxicants in plants varied widely, depending on the level of pollution in the adjacent area. The maximum concentrations of Cu, Zn and Pb were noted in the organs of the water hyacinth and reeds in the lands within the industrial areas, and the highest levels of As and Cd were noted up the stream, before the river entrance into the industrial area. The content of Fe in all areas remained stable. The difference in heavy metals’ concentrations in plants close to the banks in the provinces and in the middle of the river in most cases was not statistically significant.