Inferring the perennial biomass and phytoremediation potential of thirty-one woody species from large phytomanagement field trials

Growing woody biomass on trace element-contaminated marginal lands is a promising phytomanagement strategy, provided that species combine high productivity with appropriate contaminant accumulation profiles. In this study, we evaluated the five-year field performance and phytomanagement potential of 31 woody species established at three French trace element-contaminated sites differing in soil properties and contamination histories: Thann, Carrières-sous-Poissy, and Leforest. Above- and belowground fresh biomasses were quantified, rhizospheric soil pH and CaCl2-extractable elements were measured, and trace element concentrations were analysed in leaves, bark, and trunk tissues of two species common to all sites, Salix aquatica ‘Grandis’ and Ostrya carpinifolia. Strong interspecific and intersite variability in field biomass was observed. At Carrières-sous-Poissy, Elaeagnus umbellata and Acer saccharinum showed the highest fresh biomass, whereas Salix alba and Alnus subcordata performed best at Leforest, and Ostrya carpinifolia and Salix alba produced the highest fresh biomass at Thann. Shoot and root fresh biomasses were strongly correlated at each site. Soil pH showed only non-significant numerical trends among species, whereas selected CaCl2-extractable elements differed between planted groups and site-specific controls. Salix aquatica ‘Grandis’ accumulated high Cd and Zn concentrations in leaves and bark, but its maximum mean foliar concentrations remained below the operational hyperaccumulation thresholds for both elements. Ostrya carpinifolia displayed comparatively low trace element concentrations. These results highlight the need for site-specific selection of woody species and identify complementary candidates for phytoextraction, biomonitoring, and phytostabilization in contaminated-land phytomanagement.