Metal fluxes and stresses in terrestrial ecosystems: synopsis towards holistic understanding

Abstract

A synopsis is presented on the outcome of the multidisciplinary conference on "Metal Fluxes and Stresses in Terrestrial Ecosystems", held in Ascona/Switzerland, October 15-20, 2005. The synopsis pursues the rationale of a spatio-temporal scaling concept, as did the program structure of the conference, integrating mobility and availability of heavy metals (HMs) in soils, HM pathways through cell walls of root tips to aboveground plant parts, effect scaling between the cell and whole-plant level in relation to HM defense and evolutionary aspects, consequences of HM contamination in plant communities, and the applied aspect of phytoremediation. Major research needs were located regarding the quantification of HM fluxes and mass balances at the soil, whole-plant and system level, with particular attention to be directed to the interface between plants and the mycorrhizosphere. In scaling, relationships between HM bioavailability and life quality issues must be considered, implying an interdisciplinary view across biology, ecology, environmental chemistry, physics and medicine. HM contamination is crucial in "Global Change" scenarios, in terms of coupled biogeochemical cycling between the fluxes of carbon, water, metal and non-metal nutrients as well as HMs, and in relation to post-Kyoto policies. Only a mechanistic understanding of HM fluxes can provide a scientifically reliable basis for legislation, risk assessment and decision-making.