The role of heavy metals and toxic amterials in the physiological ecology of submersed macrophytes

摘要: Abstract An overview of, and information from, a number of publications dealing with the availability, uptake rates accumulation metals (e.g. Fe, Cu, Cr, Cd, Pb) organic substances polychlorinated biphenyls (PCB) pesticides) by submersed floating macrophytes are provided. Differences in metal enrichment reported to be dependent mainly on plant species, seasonal growth rate changes, tissue age, or compound type. A brief review possible sites absorption is given role played roots shoots discussed. higher concentration plants usually, but not always, indicates proportional increase element levels water and/or sediments. Consequently, implications for use as phytogeochemical indicators other toxic materials bodies also evaluated. Competition between elements factors, indirectly influencing such as, example, light conditions eutrophication, seem limit some cases utility using bio-indicators. Further, effects metals, particularly Cu few compounds photosynthesis species described. In considering all these aspects, importance several environmental factors pH, hardness, nutrient concentration) macrophyte-toxic cycle occurring aquatic system has been emphasized. It noted how contradictory results often emerge because large differences existing both sampling time methods used different working groups. As general rule, it seems extremely difficult extrapolate field from one another.