Seasonal variations in levels of heavy metals in leaves of Ceratophyllum demersum from Al-Garaf canal at Thi-qar province, Iraq

Abstract

The present investigation represents a part of a comprehensive ecoioglcal work aiming to evaluate the environmental status of Al- Garaf canal at Thi-Qar Province.It is, specifically , taking in consideration determining the seasonal variations in levels of some heavy etals (i.e. Ni,Ca, and Cu & Zn) in leaves of submerged aquatic plant (Ceratophyllum demersum) .The study was performed on seasonal basis. Samples were collected from a iocation supply Basrah Thi – Qar Shatra and Garaf water purification units withcrude low salinity fresh water . The specified location receives effluents from the surrounding uran areas, enriched with some industrial wastes domestic sewage and maintains fishing activities . It represents a mixing zone of water masses .The study deduced that accumulation varies seasonally within the plant leaves ,but Ni(85.71ug/gD.W)and Zn (48.90ug/gD.W)showed the highest levels and the minimal excusive value exhibited by Cd (1.81ug/gD.W) Recovered elements can be arranged as follows :Ni  ZnCu Cd.