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 6.2.1 Execution
of the experiments
6.2.2 Balance
of nitroaromatic compounds (NAC)
6.2.3 Tolerance
of trees to nitroaromatics
6.2.4 Simulation of
dendroremediation
6.2.5 Predictability of
dendroremediation
For
the faster estimation of the dendroremediation potential and of the
dendrotoxicity, as a supplemental confirmation of the outdoor experiments
and as a cross link to the radiotracer investigations with [14 C]-TNT,
additional timesaving greenhouse experiments were accomplished.
Goal
The
main goal of these experiments was the exact quantification (in amount and time)
of the added nitroaromatics, to yield realistic and replicable mass balances.
Furthermore, pollutant application should be restricted to the bioavailable portion and a continuous contaminant supply should be ensured,
i.e. application to trees should take place in water solved form o the
pollutant, very similar to the tree uptake from the contaminated soil solution
under field conditions.
Remarks
Conventional
phytotoxicity testing by direct planting into contaminated soil does not
consider the dynamic character of pollutant degradation, caused by drastic
activation of microbial consortia after soil homogenization and aeration during
pot filling. It also ignores the known planting shock, which is especially extreme
after planting tree plants. Besides, it is impossible to transplant more adult trees
into contaminated soil without measuring artifacts during the early weeks of the
experiment.
last update: 18.02.04 19:19 by Bernd
Schoenmuth@yahoo.de, Web date: June 2002
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