Please use this identifier to cite or link to this item:
|Title:||Uptake of heavy metals from contaminated sediments by salt-marsh plants|
|Authors:||Delta Institute for Hydrobiological Research (Yerseke, Netherlands)|
Long-Term Effects of Dredging Operations Program (U.S.)
Huiskes, A. H. L.
|Publisher:||Environmental Laboratory (U.S.)|
Engineer Research and Development Center (U.S.)
Abstract: Spartina anglica, Puccinellia maritima, and Aster tripolium, three common salt-marsh species in Western Europe, were grown in contaminated sediment from the port area of Antwerp, Belgium. Growth and levels of heavy metal contamination were compared with those of Spartina alterniflora, a common salt-marsh species from the United States. The plants were grown under waterlogged and drained soil conditions. In both cases, high and low soil salinities were maintained. The levels of heavy metals in the shoots of the plants were generally higher under drained conditions. The difference in salinity gave no obvious differences in metal levels in the shoots. Plants grown in the same sediment which had been aerated and allowed to dry out had higher levels of heavy metals in their shoots. The four plant species showed different levels of metals in the shoots when grown under the same conditions: P. maritima had the lowest levels, and A. tripolium had the highest . Aster tripolium also showed a significant difference in metal levels in leaf and stem material. In 1984 the same experiment was carried out with S. alterniflora, A. tripolium, and P. maritima. After the first harvest, the underground parts of the plants were left untouched to allow regrowth for an additional 90-day period. After this period, the plants were harvested again, and the shoots analyzed. The regrowth of A. tripolium and of P. maritima at high salinity was nil. Therefore, only the results of P. maritima grown at low salt conditions and of S. alterniflora were statistically analyzed. Levels of Cadmium (Cd), manganese (Mn), and copper (Cu) in the regrowth shoots of the second harvest were in general higher than in shoots of the first harvest. In contrast, levels of iron (Fe) were generally lower. Comparisons of lead (Pb), zinc (Zn), and arsenic (As) levels gave variable results. To compare heavy metal uptake by different plant species under field conditions, buckets as used in the greenhouse experiment were buried in the bank of a tidal creek in a Western Scheldt salt marsh. The location was just across from the spot where the sediment for the greenhouse experiment had been dredged. Levels of Cd, Pb, Fe, Cu, Zn, and As did not differ significantly in S. alterniflora and S. anglica. A significant difference was found in the level of Mn in these two related species. The levels of the various metals (with the exception of Mn) were lower in the Spartina spp. than in A. tripolium and P. maritima. The results of the field experiment have been compared with the metal levels found in the experiments in the greenhouse. Levels of Pb, Fe, Cu, As, Cd, and Zn were higher in the field-grown specimens than in the plants grown in the greenhouse. In contrast, Mn levels were always higher in the greenhouse plants than in the specimens grown in the field.
|Appears in Collections:||Contract Report|