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Project directory according to Nr.3.2 BNBest-BMBF98 <http://www.fz-juelich.de/ptj/datapool/page/490/Schlussbericht.rtf> 7 Usability of the resultsMethodical-experimental usesThe methods developed for the estimation of the TNT dendroremediation potential are applicable for further explosive-specific pollutants. In addition, the methods are applicable to other organics with a good or moderate mobility and the developed test systems are usable for inorganics. The methods are usable for individual measurements of growth and transpiration responses of single trees, for tree groups (example) and for tree stands (example). It should be stressed, that the newly developed wick application systems for long-term applications are specially suited for older trees, with mature physiological characteristics. The double-tray wick application systems (examples for Picea glauca and for Salix) are constructed in a manner, that apart from the demonstrated liquid application methods, for further projects the inner (bottom) tray can be filled with real contaminated soil or pollutant-spiked substrates. To test dendroremediation effects water saturation of the soil is adjustable in these systems. Practical useThe majority of the obtained results of the project leads to direct practical use possibilities for tree-based sanitation methods. Trees are superior to the use of herbaceous plants for phytoremediation, because of the general known sustainability of tree plantings and the low soil requirements. After up-scaling, the presented tree trays are suited for tree based waste water purification. It should be remarked, that the pollutant tolerance of tree based systems is generally higher than those of herbaceous plants. Basing on experimental greenhouse results, on radiotracer estimations of the TNT-degradation potential, on tree specific yield measurements in the field, and transpiration quantifications, the dendroremediation potential of newly planted trees is roughly calculable. In a similar manner, the remediation potential of middle European site forests and thus their influence on the processes of "natural attenuation" is predictable. The selection and the use of the examined trees must be site specific, whereby the tree characteristics, summarized in the tables offer an orientation. On a long-term basis, in the sense of sustainability, in middle Europe, forests planting with coniferous trees should be preferred for dendroremediation purposes. Winter transpiration of conifers and their higher interception (crown retardation of the precipitation water), is leading to lower leaching rates. Mixed plantings of conifers together with deciduous trees, with later thinning out of broadleaved trees, however, secures a faster initial success. last
update: 18.02.04 19:26 by Bernd
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