Please consult the following article :

1, Bioavailability and effects of heavy metals on soil microbial biomass survival during laboratory incubation by Leita et al (1995). Biol Fertil Soils 19:103,

doi: 10.1007/BF00336144

2. Soil Characterisation in subtropical forest crossed by highways ( Cantareira State Park, Sp, Brazil) by Flues et al (2004), Journal of the Brazilion Chemical Society 15 (4),

http://dx.doi.org/10.1590/S0103-50532004000400009.

Thank You so much Tarafdar Sir. 

Ti concentration of the aerial parts of plants is regarded by many as an index of particulate soil contamination on their surfaces

Thank you Milham Sir.

Interesting work relating the on-going discussion...

Abstract : Total heavy metal concentrations in marine sediments are not sufficient to reliably predict detrimental biological effects. Here we provide evidence that only bioavailable heavy metals have a significant impact on benthic microbial loop functioning. Sediment samples collected along 250 km of the Apulian coast (Mediterranean Sea) were analysed for total and bioavailable heavy metals (Cr, Cd, Pb and Cu), organic matter content, bacterial abundance, biomass and carbon production and β-glucosidase activity. Sampling strategy was specifically designed to cover a wide range of environmental conditions and types of anthropogenic influences. Total heavy metal concentrations in the sediments were tightly coupled with organic matter content, whereas bioavailable heavy metal concentrations displayed an opposite pattern. Bioavailable Cr concentrations were up to 10-fold higher than values observed for the other bioavailable metals and significantly inhibited benthic bacterial metabolism and turnover. Results from this study suggest that functional microbial variables are highly sensitive to heavy metal contamination and could be used as bioindicators of stress conditions in coastal sediments. Sourcec : World Journal of Microbiology and Biochemistry. 19: 93-100...