Poplar for the phytomanagement of boron contaminated sites.
Boron (B) is a widespread environmental contaminant that is mobile relative to other trace elements. We investigated the potential of hybrid poplar (Populus sp.) for B phytomanagement using a lysimeter experiment and a field trial on B-contaminated wood-waste. In both studies, poplars enhanced evapotranspiration from the wood-waste, reduced B leaching, and accumulated B in the aerial portions of the tree. When grown in a substrate containing 30 mg/kg B, poplar leaves had an average B concentration of 845 mg/kg, while the stems contained 21 mg/kg B. Leaf B concentrations increased linearly with leaf age. A decomposition experiment revealed that abscised leaves released 14% of their B during the winter months. Fertiliser application enhanced tree growth without decreasing the leaf B concentrations. Harvesting alternate rows of trees on a contaminated site would reduce leaching from the site while removing B. Harvested plant material may provide bioenergy, stock fodder, or an amendment for B-deficient soils.
Robinson
B H
BH
Institute of Terrestrial Ecosystems, Swiss Federal Institute of Technology (ETH), Universitätstrasse 16, CH-8092 Zürich, Switzerland. brett.robinson@env.ethz.ch
Green
S R
SR
Chancerel
B
B
Mills
T M
TM
Clothier
B E
BE
D001673:Biodegradation, Environmental; D001895:Boron / Q000032:analysis / Q000633:toxicity*; D007220:Industrial Waste; D009520:New Zealand; D018515:Plant Leaves / Q000737:chemistry; D032107:Populus / Q000502:physiology*; D012989:Soil Pollutants / Q000032:analysis / Q000633:toxicity*; D014934:Wood
D007220:Industrial Waste; D012989:Soil Pollutants; D001895:Boron