Synthetic zeolites as amendments for sewage sludge-based compost.
The effects of incorporating a synthetic zeolite (Zeolite P) in a range of concentrations (0.1-1.0 w:w) into an experimental horticultural compost, derived from sewage sludge, have been investigated. The impact of zeolite treatment on time-related changes of the labile zinc, copper, iron and manganese pools within the compost was compared to lime incorporation (5% w:w) and to a proprietary unamended peat-based compost. Addition of 0.5% and 1.0% zeolite significantly reduced labile zinc over a 90 day period. The highest zeolite treatment was more effective than liming; 0.5% zeolite was as effective as lime. Plant growth trials measuring transfer of metals to ryegrass (Lolium perenne L. cv Elka) in successive harvests demonstrated that both 1.0% zeolite and 5% lime treatment caused significant reduction in total metal transfer from soil-plant over a 116 day growth period. It is concluded that the use of synthetic zeolite as an amendment for compost of this type significantly reduces potential for soil metal mobility and soil-plant transfer.
Nissen
L R
LR
School of Biological and Earth Sciences, Liverpool John Moores University, UK.
Lepp
N W
NW
Edwards
R
R
D008129:Lolium / Q000737:chemistry / Q000254:growth & development; D019216:Metals, Heavy / Q000493:pharmacokinetics; D012722:Sewage; D012989:Soil Pollutants / Q000493:pharmacokinetics*; D014018:Tissue Distribution; D017641:Zeolites / Q000737:chemistry*
D019216:Metals, Heavy; D012722:Sewage; D012989:Soil Pollutants; D017641:Zeolites