Interaction of contaminated sediment from a salt marsh with estuarine water: evaluation by leaching and ecotoxicity assays and salts from leachate evaporation
| Autor: | Maria Manuela Abreu, Sara Leitão, Sara Peres, Ana Paula Santos, M. Clara F. Magalhães, Maria José Cerejeira |
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| Jazyk: | angličtina |
| Rok vydání: | 2016 |
| Předmět: |
Pollution
SPARTINA-MARITIMA 010504 meteorology & atmospheric sciences Stratigraphy media_common.quotation_subject 010501 environmental sciences engineering.material SCHELDT ESTUARY 01 natural sciences TOXICITY HEAVY-METAL MOBILITY chemistry.chemical_compound PORTUGAL PLANTS 14. Life underwater Leachate Sulfate Leaching (agriculture) 0105 earth and related environmental sciences Earth-Surface Processes media_common ACCUMULATION Polyhalite Sediment 6. Clean water chemistry 13. Climate action Environmental chemistry engineering Carbonate INTERTIDAL SEDIMENTS Ecotoxicity HALIMIONE-PORTULACOIDES TAGUS ESTUARY |
| Zdroj: | Repositório Científico de Acesso Aberto de Portugal Repositório Científico de Acesso Aberto de Portugal (RCAAP) instacron:RCAAP |
| Popis: | Purpose Wastes from a former Portuguese steel plant were deposited between 1961 and 2001 on the riverbank of a tributary of the Tagus River creating a landfill connected to the river, posing a potential contamination risk to the Tagus estuary ecosystem. This study aims to assess the transfer of chemical elements from contaminated sediments to the estuarine water from cycles of sediment leaching so as to evaluate the ecotoxicity of the leachates, and to analyze the solid phases crystallized from those leachates. Materials and methods Landfill sediment and estuarine water samples were collected during low tide. Sediment samples were analyzed for pH, electric conductivity (EC), C-org, NPK, and iron oxides. Leaching assays (four replicates) were done using estuarine water (200 cm(3)/replicate) and 1.5 kg of sediment per reactor. Each reactor was submitted to four leaching processes (0, 28, 49, and 77 days). The sediment was kept moist between leaching processes. Sediment (total (acid digestion) and available fraction (diluted organic acid extraction- Rhizo)) elemental concentrations were determined by inductively coupled plasma-instrumental neutron activation analysis (ICP/INAA). Leachates, and estuarine and sediment pore waters were analyzed for metals/metalloids by ICP/mass spectrometry (MS) and carbonates/sulfate/chloride by standard methodologies. Ecotoxicity assays were performed in leachates and estuarine and pore waters using Artemia franciscana and Brachionus plicatillis. Aliquots of the leachates were evaporated to complete dryness (23-25 degrees C) and crystals analyzed by X-ray powder diffraction (XRD). Results and discussion Sediment with pH=8 and high EC and Corg was contaminated with As, Cd, Cr, Cu, Pb, and Zn. The element concentrations in the available fraction of the sediment were low compared to the sediment total concentrations ( |
| Databáze: | OpenAIRE |
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