Halophyte vegetation influences in salt marsh retention capacity for heavy metals.
We analysed concentrations of Cu, Cd and Pb in above and belowground tissues of the halophyte species Halimione portulacoides and Spartina maritima, as well as in sediments and pore water between the roots in a Tagus estuary salt marsh (Portugal). From these results we calculated the pools of metals in the compartments mentioned above. Relative percentages of accumulation in each pool were also determined. Our aim was to determine how the type of vegetation in the salt marsh affects overall metal retention capacity of the system. It was concluded that areas colonised by H. portulacoides are potential sources of Cu, Cd and Pb to the marsh ecosystem, whereas areas colonised by S. maritima are more effective sinks at least for Cu and Cd. Consequently, S. maritima seems to contribute more effectively to the stabilisation of metals in salt marsh sediments, reducing their availability to the estuarine system.
Reboreda
Rosa
R
Institute of Oceanography, Faculty of Sciences, University of Lisbon, Campo Grande, Rua Ernesto de Vasconcelos, 1749-016 Lisbon, Portugal.
Caçador
Isabel
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D001673:Biodegradation, Environmental; D002104:Cadmium / Q000032:analysis; D003300:Copper / Q000032:analysis; D017753:Ecosystem; D004784:Environmental Monitoring / Q000379:methods; D019015:Geologic Sediments / Q000737:chemistry; D007854:Lead / Q000032:analysis; D019216:Metals, Heavy / Q000032:analysis*; D018517:Plant Roots / Q000737:chemistry; D018520:Plant Shoots / Q000737:chemistry; D010944:Plants / Q000737:chemistry*; D011174:Portugal; D012623:Seawater; D014874:Water Pollutants, Chemical / Q000032:analysis*; D053833:Wetlands
D019216:Metals, Heavy; D014874:Water Pollutants, Chemical; D002104:Cadmium; D007854:Lead; D003300:Copper