Carbon sequestration and nutrient accumulation in floodplain and depressional wetlands

• Published in: Ecological engineering Vol. 114; pp. 137 - 145
• Main Authors: Craft, Christopher, Vymazal, Jan, Kröpfelová, Lenka
• Format: Journal Article
• Language: English
• Published: Amsterdam Elsevier B.V 15.04.2018; Elsevier BV
• Subjects: Accretion; Agricultural land; Agriculture; Carbon; Carbon sequestration; Cores; Deposition; Erosion; Floodplains; Freshwater; Geomorphic; Inland water environment; Land use; Landscape; Landscape position; Lead isotopes; Mental depression; Mineral nutrients; Nitrogen; Nutrient retention; Nutrients; Organic carbon; Organic phosphorus; Organic soils; Pasture; Phosphorus; Retention; Sediment; Sediments; Soil; Soil erosion; Soils; Wetlands; Bohemia; Midwest states; Sediment; Nutrients; Phosphorus; Landscape position; Agriculture; Nitrogen; Geomorphic; Carbon; Land use; Erosion
• ISSN: 0925-8574; 1872-6992
• DOI: 10.1016/j.ecoleng.2017.06.034

•Wetland C sequestration and nutrient retention depends on their landscape position.•In agricultural landscapes, land use intensity drives C and nutrient retention.•Mineral soil wetland sequester as much C as peatlands, though burial by sediment. We measured soil organic carbon (C) sequestration and nutrient (nitrogen-N, phosphorus- P) burial in Czech and Midwest U.S. freshwater floodplain and depressional wetlands to evaluate how landscape position and agricultural land use intensity affects C, N, and P retention. Land use in the South Bohemia of the Czech Republic is dominated by forest and pasture, whereas in the Midwest U.S., land use is dominated by row crop agriculture. Cs-137 and 210Pb dating of soil cores revealed comparable rates of soil accretion among wetland types, ranging from 0.5mm/yr in a Czech floodplain wetland to 2.3mm/yr in a U.S. depressional wetland. Carbon sequestration and N & P burial did not differ among floodplain (47+14gC/m2/yr, 3.7+1gN/m2/yr, 0.47+0.16g P/m2/yr) and depressional wetlands (50+19g/m2/yr, 3.6+1.3gN/m2/yr, 0.51+0.14g P/m2/yr). However, sediment deposition in Czech floodplain and depressional wetlands was only 10–50% (150–340g/m2/yr) of rates measured in U.S. wetlands (650–1460g/m2/yr). Our results suggest that, in agricultural landscapes, land use intensity rather than landscape position – floodplain versus depression – drives wetland C sequestration and nutrient retention through increased sediment deposition.