caa a22 4500 605517495 CHVBK 20210128100720.0 cr unu---uuuuu 210128e20151101xx s 000 0 eng 10.1007/s10533-015-0140-1 doi (NATIONALLICENCE)springer-10.1007/s10533-015-0140-1 Salinization of coastal freshwater wetlands; effects of constant versus fluctuating salinity on sediment biogeochemistry [Elektronische Daten] [Gijs van Dijk, Alfons Smolders, Roos Loeb, Astrid Bout, Jan Roelofs, Leon Lamers] Globally, coastal lowlands are becoming more saline by the combined effects of sea level rise, land subsidence and altered hydrological and climatic conditions. Although salinization is known to have a great influence on biogeochemical processes, literature shows contrasting effects that challenge the prediction of future effects. In addition, the effects of fluctuating salinity levels, a more realistic scenario than constant levels, on nutrient cycling in coastal wetland sediments have hardly been examined. A better understanding is therefore crucial for the prediction of future effects and the definition of effective management. To test the effects of constantly brackish water (50mmol Cll−1, 3.2 psu) or fluctuating salinity (5-50mmol Cll−1), versus constantly low salinity (5mmol Cll−1, 0.32 psu) on nutrient biogeochemistry, we conducted a controlled laboratory experiment with either peat or clay sediments from coastal wetlands. Increased salinity showed to have a fast and large effect. Sediment cation exchange appeared to be the key process explaining both a decrease in phosphorus availability (through calcium mobilization) and an increase in nitrogen availability, their extent being strongly dependent on sediment type. Supply of brackish water decreased surface water turbidity and inhibited sediment methane production but did not affect CO2 production. Constant and fluctuating salinity levels showed similar longer term effects on nutrient and carbon cycling. The contrasting effects of salinization found for nitrogen and phosphorus, and its effects on water turbidity indicate major ecological consequences for coastal wetlands and have important implications for water management and nature restoration. Springer International Publishing Switzerland, 2015 Eutrophication nationallicence Nutrient nationallicence Carbon nationallicence Poikilohaline nationallicence Brackish nationallicence Sea level rise nationallicence van Dijk Gijs B-WARE Research Centre, Radboud University, P.O. Box 6558, 6503 GB, Nijmegen, The Netherlands aut Smolders Alfons B-WARE Research Centre, Radboud University, P.O. Box 6558, 6503 GB, Nijmegen, The Netherlands aut Loeb Roos B-WARE Research Centre, Radboud University, P.O. Box 6558, 6503 GB, Nijmegen, The Netherlands aut Bout Astrid Institute of Water and Wetland Research, Radboud University, P.O. Box 9010, 6500 GL, Nijmegen, The Netherlands aut Roelofs Jan Institute of Water and Wetland Research, Radboud University, P.O. Box 9010, 6500 GL, Nijmegen, The Netherlands aut Lamers Leon B-WARE Research Centre, Radboud University, P.O. Box 6558, 6503 GB, Nijmegen, The Netherlands aut Biogeochemistry Springer International Publishing 126/1-2(2015-11-01), 71-84 0168-2563 126:1-2<71 2015 126 10533 https://doi.org/10.1007/s10533-015-0140-1 text/html Onlinezugriff via DOI BK010053 XK010053 XK010000 Metadata rights reserved Springer special CC-BY-NC licence nationallicence 1 research-article jats NATIONALLICENCE NATIONALLICENCE NL-springer NATIONALLICENCE 856 40 https://doi.org/10.1007/s10533-015-0140-1 text/html Onlinezugriff via DOI NATIONALLICENCE 700 1- van Dijk Gijs B-WARE Research Centre, Radboud University, P.O. Box 6558, 6503 GB, Nijmegen, The Netherlands aut NATIONALLICENCE 700 1- Smolders Alfons B-WARE Research Centre, Radboud University, P.O. Box 6558, 6503 GB, Nijmegen, The Netherlands aut NATIONALLICENCE 700 1- Loeb Roos B-WARE Research Centre, Radboud University, P.O. Box 6558, 6503 GB, Nijmegen, The Netherlands aut NATIONALLICENCE 700 1- Bout Astrid Institute of Water and Wetland Research, Radboud University, P.O. Box 9010, 6500 GL, Nijmegen, The Netherlands aut NATIONALLICENCE 700 1- Roelofs Jan Institute of Water and Wetland Research, Radboud University, P.O. Box 9010, 6500 GL, Nijmegen, The Netherlands aut NATIONALLICENCE 700 1- Lamers Leon B-WARE Research Centre, Radboud University, P.O. Box 6558, 6503 GB, Nijmegen, The Netherlands aut NATIONALLICENCE 773 0- Biogeochemistry Springer International Publishing 126/1-2(2015-11-01), 71-84 0168-2563 126:1-2<71 2015 126 10533