Linked Life Data

15224934

Source:http://linkedlifedata.com/resource/pubmed/id/15224934

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
3
pubmed:dateCreated
2004-6-30
pubmed:abstractText
Willow (Salix spp.) stands are often proposed as vegetation covers for the restoration and stabilization of contaminated and derelict land. Planting willows on dredged sediment disposal sites for biomass production can be an alternative to traditional capping techniques. However, with the introduction of willow stands on dredged sediment disposal sites, the possibility of increased contaminant availability in the root zone must be acknowledged as it can increase the risk of leaching. Two trials investigated the availability of Cd, Zn, Cu, and Pb in the root zones of willows grown on contaminated sediment. To assess the effects of willow root growth on metal extractability and mobility, bulk and rhizosphere sediment samples were extracted with deionized water, ammonium acetate at pH 7, and ammonium acetate-EDTA at pH 4.65. A rhizobox experiment was used to investigate the short-term effect of willow roots on metal availability in oxic and anoxic sediment. Longer-term effects were assessed in a field trial. The rhizobox trial showed that Cd, Zn, and Cu extractability in the rhizosphere increased while the opposite was observed for Pb. This was attributed to the increased willow-induced oxidation rate in the root zone as a result of aeration and evapotranspiration, which masked the direct chemical and biological influences of the willow roots. The field trial showed that Cu and Pb, but not Cd, were more available in the root zone after water and ammonium acetate (pH 7) extraction compared with the bulk sediment. Sediment in the root zone was better structured and aggregated and thus more permeable for downward water flows, causing leaching of a fraction of the metals and significantly lower total contents of Cd, Cu, and Pb. These findings indicate that a vegetation cover strategy to stabilize sediments can increase metal availability in the root zone and that potential metal losses to the environment should be considered.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:issn
0047-2425
pubmed:author
pubmed:issnType
Print
pubmed:volume
33
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
976-83
pubmed:dateRevised
2006-11-15
pubmed:meshHeading
pubmed:articleTitle
Short- and longer-term effects of the willow root system on metal extractability in contaminated dredged sediment.
pubmed:affiliation
Department of Applied Analytical and Physical Chemistry, Laboratory of Analytical Chemistry and Applied Ecochemistry, Ghent University, Coupure Links 653, 9000 Ghent, Belgium. Pieter.Vervaeke@UGent.be
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't