On-Site and Full-Scale Applications of Phytoremediation to Repair Aquatic Ecosystems with Metal Excess

Abstract

There are a few studies about full scale and on-site treatments using macrophytes. In this contribution we compare the phytoremediation role of floating, submersed, and emergent macrophytes grown in natural and artificial wetlands. Metal uptake capacity of aquatic plants is low and this exclusion strategy seems to be more widespread among aquatic plants. Bioconcentration factors and translocation are lower than those calculated in bioassays conducted under laboratory conditions. There are not hyperaccumulators among the studied plants. However, regarding the capacity of accumulation of metals in the standing crop, the floating plants are most effective for phytoextraction, followed by submersed species and then emergent species. The emergent plants are more effective for phytostabilization. The metals released during the decomposition could be further retained by the new binding sites generated in bottom sediment. Use of native species in remediation projects, not always considered in scientific or technical papers is essential to preserve biological diversity and, requires more detailed studies for each natural ecosystem.