BRYOPHYTES: A USEFUL BIOMONITORING TOOL FOR HEAVY METAL POLLUTION CAUSED BY INDUSTRIAL WASTE.

The species diversity of bryophytes growing under the influence of heavy metal industries of Rajasthan were studied to determine the absorption and accumulation of heavy metals potential and use them as biomonitoring tool. Seven bryophytes were collected from different localities of the surrounding industrial areas from the Hindustan Zinc Smelter Debari (HZS) Udaipur; and Hindustan Copper Smelter (HCS) Khetri, Jhunjhunu. The collected bryophytes belonged to two important taxonomic groups: (1) mosses, such as Funaria hygrometrica Hedw. (Pottiaceae), Hyophila involuta (Hook.) A. Jaeger (Pottiaceae), Barbula constricta Mitt. (Pottiaceae), Hydrogonium consenguineum (Thwaites & Mitt.) Hilp. (Pottiaceae), Bryum recurvulum Mitt. (Bryaceae); and (2) liverworts such as Plagiochasma appendiculatum Lehm & Lindenb. (Aytoniaceae) and Riccia glauca L. (Ricciaceae). The heavy metal absorption and deposition efficiency were determined by using Atomic absorption Spectrophotomer from digested plant samples in nitric and hydrochloric acid (HNO3-HCl, 1-3 ratio) mixture. Results showed that high absorption and accumulation of Zn and Cu were observed in moss F. hygrometrica (54.26 and 55.96 ppm) followed by H. involuta (51.33 and 46.12) and B. constricta (50.98 and 51.97). A liverwort P. appendiculatum accumulated comparatively less amount of Zn and Cu (48.78 and 44.88 ppm) respectively suggesting that mosses are more efficient to absorb and accumulate heavy metals than liverworts very less amount of Pb and Cd was also reported in all analyzed samples. In vitro studies of selected bryophytes showed that F. hygrometrica and B. constricta survived upto 50 ppm concentrations of Zn and Cu contaminated culture medium whereas P. appendiculatum only upto 40 ppm concentrations of both the heavy metals with high percentage of regenerants and gametophores formation. The present study revealed that mosses and liverworts have a significant potential to absorb and accumulate heavy metals, making them useful biomonitoring tool. Further this study will also unlock the naturally occurring bryophytes may be used as pollution monitoring agents due to their high efficiency of absorption and accumulation of heavy metals growing in contaminated environment.