Cadmium and zinc uptake by volunteer willow species and elder rooting in polluted dredged sediment disposal sites.
Salix species and Sambucus nigra L. (elder) naturally invade dredged sediment landfills and are commonly encountered on substrates contaminated with heavy metals. Foliar concentrations of Cd and Zn in four Salix species and elder were explored in the field. Metal contents in dredged sediment derived soils were elevated compared to baseline concentration levels reported for Flanders. To evaluate foliar concentrations, reference data were compiled from observations in nurseries, young plantations and unpolluted sites with volunteer willow vegetation. Willows grown on polluted dredged sediment landfills showed elevated foliar Cd and Zn concentrations (>6.6 mg Cd/kg DW and >700 mg Zn/kg DW). This was not the case for elder. For willow, a significant relation was found between soil total Zn or Cd and foliar Zn or Cd, regardless of age, species, or clone. Willows proved to be useful bioindicators. Results indicated a possible threat in long-term habitat development of willow brushwood from transfer of Cd and Zn to the food web.
Vandecasteele
Bart
B
Institute for Forestry and Game Management, Ministry of the Flemish Community, Gaverstraat 4, B-9500 Geraardsbergen, Belgium. bart.vandecasteele@lin.vlaanderen.be
De Vos
Bruno
B
Tack
Filip M G
FM
D002104:Cadmium / Q000493:pharmacokinetics*; D003247:Conservation of Natural Resources; D004784:Environmental Monitoring; D019015:Geologic Sediments / Q000737:chemistry*; D018515:Plant Leaves / Q000737:chemistry; D018517:Plant Roots / Q000737:chemistry / Q000502:physiology; D012037:Refuse Disposal; D032108:Salix / Q000737:chemistry*; D027923:Sambucus / Q000737:chemistry*; D012989:Soil Pollutants / Q000493:pharmacokinetics*; D015032:Zinc / Q000493:pharmacokinetics*
D012989:Soil Pollutants; D002104:Cadmium; D015032:Zinc