Benthic nitrogen metabolism in a macrophyte meadow (Vallisneria spiralis L.) under increasing sedimentary organic matter loads
(2015) In Biogeochemistry 124(1-3). p.387-404- Abstract
- Organic enrichment may deeply affect benthic nitrogen (N) cycling in macrophyte meadows, either promoting N loss or its recycling. This depends upon the plasticity of plants and of the associated microbial communities, as those surrounding the rhizosphere. Rates of denitrification, dissolved inorganic N fluxes and N uptake were measured in sediments vegetated by the submerged macrophyte Vallisneria spiralis L. under increasing organic matter loads. The aim was to investigate how the combined N assimilation and denitrification, which subtract N via temporary retention and permanent removal, respectively, do vary along the gradient. Results showed that V. spiralis meadows act as regulators of benthic N cycling even in organic enriched... (More)
- Organic enrichment may deeply affect benthic nitrogen (N) cycling in macrophyte meadows, either promoting N loss or its recycling. This depends upon the plasticity of plants and of the associated microbial communities, as those surrounding the rhizosphere. Rates of denitrification, dissolved inorganic N fluxes and N uptake were measured in sediments vegetated by the submerged macrophyte Vallisneria spiralis L. under increasing organic matter loads. The aim was to investigate how the combined N assimilation and denitrification, which subtract N via temporary retention and permanent removal, respectively, do vary along the gradient. Results showed that V. spiralis meadows act as regulators of benthic N cycling even in organic enriched sediments, with negative feedbacks for eutrophication. A moderate organic load stimulates N uptake and denitrification coupled to nitrification in the rhizosphere. This is due to a combination of weakened competition between macrophytes and N cycling bacteria and enhanced radial oxygen loss by roots. An elevated organic enrichment affects N uptake due to hostile conditions in pore water and plant stress and impairs N mineralisation and its removal via denitrification coupled to nitrification. However, the loss of plant performance is almost completely compensated by increased denitrification of water column nitrate, resulting in a shift between the relative relevance of temporary and permanent N removal processes. (Less)
Please use this url to cite or link to this publication:
https://lup.lub.lu.se/record/8522757
- author
- Soana, Elisa ; Naldi, Mariachiara ; Bonaglia, Stefano LU ; Racchetti, Erica ; Castaldelli, Giuseppe ; Bruchert, Volker ; Viaroli, Pierluigi and Bartoli, Marco
- publishing date
- 2015
- type
- Contribution to journal
- publication status
- published
- subject
- keywords
- N fluxes, Radial oxygen loss, Vallisneria spiralis, Organic enrichment, N uptake, Denitrification
- in
- Biogeochemistry
- volume
- 124
- issue
- 1-3
- pages
- 387 - 404
- publisher
- Springer
- external identifiers
-
- wos:000355620200025
- scopus:84930272786
- ISSN
- 1573-515X
- DOI
- 10.1007/s10533-015-0104-5
- language
- English
- LU publication?
- no
- id
- 70d8283b-efb9-4d28-beae-775764e18b78 (old id 8522757)
- date added to LUP
- 2016-04-01 10:10:41
- date last changed
- 2022-03-04 08:56:48
@article{70d8283b-efb9-4d28-beae-775764e18b78, abstract = {{Organic enrichment may deeply affect benthic nitrogen (N) cycling in macrophyte meadows, either promoting N loss or its recycling. This depends upon the plasticity of plants and of the associated microbial communities, as those surrounding the rhizosphere. Rates of denitrification, dissolved inorganic N fluxes and N uptake were measured in sediments vegetated by the submerged macrophyte Vallisneria spiralis L. under increasing organic matter loads. The aim was to investigate how the combined N assimilation and denitrification, which subtract N via temporary retention and permanent removal, respectively, do vary along the gradient. Results showed that V. spiralis meadows act as regulators of benthic N cycling even in organic enriched sediments, with negative feedbacks for eutrophication. A moderate organic load stimulates N uptake and denitrification coupled to nitrification in the rhizosphere. This is due to a combination of weakened competition between macrophytes and N cycling bacteria and enhanced radial oxygen loss by roots. An elevated organic enrichment affects N uptake due to hostile conditions in pore water and plant stress and impairs N mineralisation and its removal via denitrification coupled to nitrification. However, the loss of plant performance is almost completely compensated by increased denitrification of water column nitrate, resulting in a shift between the relative relevance of temporary and permanent N removal processes.}}, author = {{Soana, Elisa and Naldi, Mariachiara and Bonaglia, Stefano and Racchetti, Erica and Castaldelli, Giuseppe and Bruchert, Volker and Viaroli, Pierluigi and Bartoli, Marco}}, issn = {{1573-515X}}, keywords = {{N fluxes; Radial oxygen loss; Vallisneria spiralis; Organic enrichment; N uptake; Denitrification}}, language = {{eng}}, number = {{1-3}}, pages = {{387--404}}, publisher = {{Springer}}, series = {{Biogeochemistry}}, title = {{Benthic nitrogen metabolism in a macrophyte meadow (Vallisneria spiralis L.) under increasing sedimentary organic matter loads}}, url = {{http://dx.doi.org/10.1007/s10533-015-0104-5}}, doi = {{10.1007/s10533-015-0104-5}}, volume = {{124}}, year = {{2015}}, }