TITLE:
Heavy Metal Accumulation Potential of Some Wetland Plants Growing Naturally in the City of Kolkata, India
AUTHORS:
Poulami Jha, Alok C. Samal, Subhash C. Santra, Anjana Dewanji
KEYWORDS:
Alternanthera philoxeroides, Eichhornia crassipes, Invasive, Ipomoea aquatica, Lead (Pb), Cadmium (Cd), Chromium (Cr)
JOURNAL NAME:
American Journal of Plant Sciences,
Vol.7 No.15,
October
28,
2016
ABSTRACT: Freshwaters are not only used locally in many developing countries but they are often
over exploited for domestic purposes, agriculture and disposal of industrial
wastes which result in an overload of excess nutrients, harmful chemicals and heavy
metals. Plant species together with sediments and water samples collected from eleven
aquatic water bodies in the vicinity of industrial units in Kolkata were studied for
their potential to uptake Pb, Cd and Cr under field conditions. Cd and Cr concentrations
in the sediments were higher than background values considered to be toxic. Alternanthera philoxeroides and Eichhornia crassipes were the two invasive species
present, with the former being more widely distributed. Among native plants, Ipomoea
aquatica was the most abundant. Metal uptake in the plants differed among
species, tissues and sites. Pb and Cd accumulation in root tissues for all plants in
most sites suggested an exclusion strategy for metal tolerance. Since I. aquatica is widely
consumed in many parts of SE Asia, its metal content should be checked before
use since it was found to efficiently translocate both Pb and Cd from roots to shoots.
The potential of A. philoxeroides as a metal excluder needs to be explored further
since it translocates less to its shoots as compared to E. crassipes and I. aquatica.