Spatial variation of copper and lead concentrations of water hyacinth plants in a wetland receiving urban run-off

Abstract

Copper and lead concentrations of roots of water hyacinth, Eichhornia crassipes (Mart.) Solms, in an urban wetland in Sydney, Australia ranged between 145 ± 15 and 1110 ± 145 μg g-2 dry mass for lead; and between 14.7 ± 7.0 and 303 ± 108 μg g-1 dry mass for copper, (mean ± sd, n = 6). Considerable variation at the scale of individual plants was found, about 20% relative standard deviation within a site of about 3 m radius. Samples of single or few plants are therefore unlikely to allow assessment of the pollution status of a wetland. Copper and lead had similar spatial distribution. Metal concentrations in the sediments, roots and leaves declined exponentially with increased distance from th..