[01] Nuzhat Shafi, Centre of Research for Development, University of Kashmir, Srinagar, India. [02] Ashok K. Pandit, Centre of Research for Development, University of Kashmir, Srinagar, India. [03] Azra N. Kamili, Centre of Research for Development, University of Kashmir, Srinagar, India. [04] Basharat Mushtaq, Centre of Research for Development, University of Kashmir, Srinagar, India.

Free floating macrophytes play a significant role in removing different types of metals from the water bodies and carry out its purification. In view of their potential Azolla pinnata were collected from Dal Lake, an urban-anthropogenic affected water body of Srinagar city and were studied for accumulation of heavy metals. Azolla pinnata were exposed to 4 mg/l concentration of different heavy metals in the form of (Cu) CuSO4, (Pb) PbNO3, (Cr) K2Cr2O7, (Cd) CdNO3 and (Zn) ZnSO4 for 10 days experimentation period in laboratory conditions. Atomic absorption spectrophotometric analysis have shown initial concentration of these metals in Azolla pinnata as Cu (0.02ppm), Pb (0.085ppm), Cr (0.07ppm), Cd (0.006ppm) and Zn (0.06ppm) and after 10 days period the plant has accumulated Cu (0.90ppm), Pb (0.42ppm), Cr (0.27ppm), Cd (0.042ppm) and Zn (2.1ppm) in the order of Zn>Cu>Pb>Cr>Cd. Present study highlights the fact that Azolla pinnata bioaccumulates large concentration of heavy metals, therefore can play an important role in the bioremediation of lake ecosystems and waste water treatment plants which are under heavy stress of anthropogenic pressure.

Heavy Metal Accumulation, Azolla pinnata, Bioremediation, Dal Lake

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