Populus nigra ,Italica

More recently plant analysis has been carried out to screen for the accumulation of metals indicative of pollution. Usually metal concentrations are reported in dry plant material. However, it has been suggested (Claussen, 1990) that the concentrations of pollutants are better related to the dry ash of a plant, than to the dry weight, since it eliminates the natural variations of organic matter. Heavy metal concentrations in ash of Populus nigra Italica were reported to correlate better with values in air and soil than those in dry plant material. 

Fig. 8-5. Comparison of results for concentrations of Zn, Pb and Cd in standardised leaves of the Lombardy poplar (Populus nigra Italica ) from different locations and years (from Wagner, 1993, reprinted with permission).

Djingova, R, Wagner, G Kuleff, 1., Peshev, D 1996. Investigation of the time-dependant variations in metal concentration in the leaves of Populus nigra Italica . Sci. Total Environ. 184, 197-203. 

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