Autochthonous organic matter promotes DNRA and suppresses N2O production in sediments of the coastal Baltic Sea
Aalto, S. L., Asmala, E., Jilbert, T., & Hietanen, S. (2021). Autochthonous organic matter promotes DNRA and suppresses N2O production in sediments of the coastal Baltic Sea. Estuarine, Coastal and Shelf Science, 255, Article 107369. https://doi.org/10.1016/j.ecss.2021.107369
Published in
Estuarine, Coastal and Shelf ScienceDate
2021Copyright
© 2021 Elsevier
Coastal environments are nitrogen (N) removal hot spots, which regulate the amount of land-derived N reaching the open sea. However, mixing between freshwater and seawater creates gradients of inorganic N and bioavailable organic matter, which affect N cycling. In this study, we compare nitrate reduction processes between estuary and offshore archipelago environments in the coastal Baltic Sea. Denitrification rates were similar in both environments, despite lower nitrate and carbon concentrations in the offshore archipelago. However, DNRA (dissimilatory nitrate reduction to ammonium) rates were higher at the offshore archipelago stations, with a higher proportion of autochthonous carbon. The production rate and concentrations of the greenhouse gas nitrous oxide (N2O) were higher in the estuary, where nitrate concentrations and allochthonous carbon inputs are higher. These results indicate that the ratio between nitrate and autochthonous organic carbon governs the balance between N-removing denitrification and N-recycling DNRA, as well as the end-product of denitrification. As a result, a significant amount of the N removed in the estuary is released as N2O, while the offshore archipelago areas are characterized by efficient internal recycling of N. Our results challenge the current understanding of the role of these regions as filters of land-to-sea transfer of N.
...
Publisher
ElsevierISSN Search the Publication Forum
0272-7714Keywords
Publication in research information system
https://converis.jyu.fi/converis/portal/detail/Publication/67406380
Metadata
Show full item recordCollections
Additional information about funding
This work was supported by the Academy of Finland (projects 267112, 309748, 310302, and 317684).License
Related items
Showing items with similar title or keywords.
-
Seasonal cycle of benthic denitrification and DNRA in the aphotic coastal zone, northern Baltic Sea
Hellemann, D.; Tallberg, P.; Aalto, S.L.; Bartoli, M.; Hietanen,S. (Inter-Research, 2020)Current knowledge on the seasonality of benthic nitrate reduction pathways in the aphotic, density stratified coastal zone of the Baltic Sea is largely based on data from muddy sediments, neglecting the potential contribution ... -
Cormorant predation mortality of perch (Perca fluviatilis) in coastal and archipelago areas, northern Baltic Sea
Heikinheimo, Outi; Marjomäki, Timo J.; Olin, Mikko; Rusanen, Pekka (Oxford University Press (OUP), 2022)Perch (Perca fluviatilis) is an important prey species of the great cormorant (Phalacrocorax carbo sinensis) in the coastal waters of the northern Baltic Sea. The annual predation mortality caused by cormorants was estimated ... -
Nitrogen removal by microbial processes in aquatic systems
Rissanen, Antti (University of Jyväskylä, 2012) -
Flotsam samples can help explain the δ13C and δ15N values of invertebrate resting stages in lake sediment
van Hardenbroek, Maarten; Rinta, Päivi; Wooller, Matthew J.; Schilder, Johannes; Stötter, Tabea; Heiri, Oliver (Pergamon Press, 2018)The stable isotopic composition of chitinous remains of Cladocera (water fleas) and freshwater Bryozoa (moss animals) preserved in lake sediment records can provide supporting insights into past environmental and ecosystem ... -
Unraveling long-term changes in lake color based on optical properties of lake sediment
Xiao, Yihua; Rohrlack, Thomas; Riise, Gunnhild (Elsevier BV, 2020)A number of boreal surface waters have become browner over the last two decades. Recovery from acid rain is regarded as an important driver for this lake color increase, indicating a general browner lake color in preindustrial ...