Cargando…

Disentangling the mechanisms sustaining a stable state of submerged macrophyte dominance against free-floating competitors

Free-floating and rootless submerged macrophytes are typical, mutually exclusive vegetation types that can alternatively dominate in stagnant and slow flowing inland water bodies. A dominance of free-floating plants has been associated with a lower number of aquatic ecosystem services and can be exp...

Descripción completa

Detalles Bibliográficos
Autores principales: Szabó, Sándor, Koleszár, Gergő, Zavanyi, Györgyi, Nagy, Péter Tamás, Braun, Mihály, Hilt, Sabine
Formato: Online Artículo Texto
Lenguaje:English
Publicado: Frontiers Media S.A. 2022
Materias:
Acceso en línea:https://www.ncbi.nlm.nih.gov/pmc/articles/PMC9660258/
https://www.ncbi.nlm.nih.gov/pubmed/36388490
http://dx.doi.org/10.3389/fpls.2022.963579
_version_ 1784830383018213376
author Szabó, Sándor
Koleszár, Gergő
Zavanyi, Györgyi
Nagy, Péter Tamás
Braun, Mihály
Hilt, Sabine
author_facet Szabó, Sándor
Koleszár, Gergő
Zavanyi, Györgyi
Nagy, Péter Tamás
Braun, Mihály
Hilt, Sabine
author_sort Szabó, Sándor
collection PubMed
description Free-floating and rootless submerged macrophytes are typical, mutually exclusive vegetation types that can alternatively dominate in stagnant and slow flowing inland water bodies. A dominance of free-floating plants has been associated with a lower number of aquatic ecosystem services and can be explained by shading of rootless submerged macrophytes. Vice versa, high pH and competition for several nutrients have been proposed to explain the dominance of rootless submerged macrophytes. Here, we performed co-culture experiments to disentangle the influence of limitation by different nutrients, by pH effects and by allelopathy in sustaining the dominance of rootless submerged macrophytes. Specifically, we compared the effects of nitrogen (N), phosphorus (P), iron (Fe) and manganese (Mn) deficiencies and an increased pH from 7 to 10 in reducing the growth of free-floating Lemna gibba by the rootless Ceratophyllum demersum. These macrophyte species are among the most common in highly eutrophic, temperate water bodies and known to mutually exclude each other. After co-culture experiments, additions of nutrients and pH neutralisation removed the growth inhibition of free-floating plants. Among the experimentally tested factors significantly inhibiting the growth of L. gibba, an increase in pH had the strongest effect, followed by depletion of P, N and Fe. Additional field monitoring data revealed that in water bodies dominated by C. demersum, orthophosphate concentrations were usually sufficient for optimal growth of free-floating plants. However, pH was high and dissolved inorganic N concentrations far below levels required for optimal growth. Low N concentrations and alkaline pH generated by dense C. demersum stands are thus key factors sustaining the stable dominance of rootless submerged vegetation against free-floating plants. Consequently, N loading from e.g. agricultural runoff, groundwater or stormwater is assumed to trigger regime shifts to a dominance of free-floating plants and associated losses in ecosystem services.
format Online
Article
Text
id pubmed-9660258
institution National Center for Biotechnology Information
language English
publishDate 2022
publisher Frontiers Media S.A.
record_format MEDLINE/PubMed
spelling pubmed-96602582022-11-15 Disentangling the mechanisms sustaining a stable state of submerged macrophyte dominance against free-floating competitors Szabó, Sándor Koleszár, Gergő Zavanyi, Györgyi Nagy, Péter Tamás Braun, Mihály Hilt, Sabine Front Plant Sci Plant Science Free-floating and rootless submerged macrophytes are typical, mutually exclusive vegetation types that can alternatively dominate in stagnant and slow flowing inland water bodies. A dominance of free-floating plants has been associated with a lower number of aquatic ecosystem services and can be explained by shading of rootless submerged macrophytes. Vice versa, high pH and competition for several nutrients have been proposed to explain the dominance of rootless submerged macrophytes. Here, we performed co-culture experiments to disentangle the influence of limitation by different nutrients, by pH effects and by allelopathy in sustaining the dominance of rootless submerged macrophytes. Specifically, we compared the effects of nitrogen (N), phosphorus (P), iron (Fe) and manganese (Mn) deficiencies and an increased pH from 7 to 10 in reducing the growth of free-floating Lemna gibba by the rootless Ceratophyllum demersum. These macrophyte species are among the most common in highly eutrophic, temperate water bodies and known to mutually exclude each other. After co-culture experiments, additions of nutrients and pH neutralisation removed the growth inhibition of free-floating plants. Among the experimentally tested factors significantly inhibiting the growth of L. gibba, an increase in pH had the strongest effect, followed by depletion of P, N and Fe. Additional field monitoring data revealed that in water bodies dominated by C. demersum, orthophosphate concentrations were usually sufficient for optimal growth of free-floating plants. However, pH was high and dissolved inorganic N concentrations far below levels required for optimal growth. Low N concentrations and alkaline pH generated by dense C. demersum stands are thus key factors sustaining the stable dominance of rootless submerged vegetation against free-floating plants. Consequently, N loading from e.g. agricultural runoff, groundwater or stormwater is assumed to trigger regime shifts to a dominance of free-floating plants and associated losses in ecosystem services. Frontiers Media S.A. 2022-10-31 /pmc/articles/PMC9660258/ /pubmed/36388490 http://dx.doi.org/10.3389/fpls.2022.963579 Text en Copyright © 2022 Szabó, Koleszár, Zavanyi, Nagy, Braun and Hilt https://creativecommons.org/licenses/by/4.0/This is an open-access article distributed under the terms of the Creative Commons Attribution License (CC BY). The use, distribution or reproduction in other forums is permitted, provided the original author(s) and the copyright owner(s) are credited and that the original publication in this journal is cited, in accordance with accepted academic practice. No use, distribution or reproduction is permitted which does not comply with these terms.
spellingShingle Plant Science
Szabó, Sándor
Koleszár, Gergő
Zavanyi, Györgyi
Nagy, Péter Tamás
Braun, Mihály
Hilt, Sabine
Disentangling the mechanisms sustaining a stable state of submerged macrophyte dominance against free-floating competitors
title Disentangling the mechanisms sustaining a stable state of submerged macrophyte dominance against free-floating competitors
title_full Disentangling the mechanisms sustaining a stable state of submerged macrophyte dominance against free-floating competitors
title_fullStr Disentangling the mechanisms sustaining a stable state of submerged macrophyte dominance against free-floating competitors
title_full_unstemmed Disentangling the mechanisms sustaining a stable state of submerged macrophyte dominance against free-floating competitors
title_short Disentangling the mechanisms sustaining a stable state of submerged macrophyte dominance against free-floating competitors
title_sort disentangling the mechanisms sustaining a stable state of submerged macrophyte dominance against free-floating competitors
topic Plant Science
url https://www.ncbi.nlm.nih.gov/pmc/articles/PMC9660258/
https://www.ncbi.nlm.nih.gov/pubmed/36388490
http://dx.doi.org/10.3389/fpls.2022.963579
work_keys_str_mv AT szabosandor disentanglingthemechanismssustainingastablestateofsubmergedmacrophytedominanceagainstfreefloatingcompetitors
AT koleszargergo disentanglingthemechanismssustainingastablestateofsubmergedmacrophytedominanceagainstfreefloatingcompetitors
AT zavanyigyorgyi disentanglingthemechanismssustainingastablestateofsubmergedmacrophytedominanceagainstfreefloatingcompetitors
AT nagypetertamas disentanglingthemechanismssustainingastablestateofsubmergedmacrophytedominanceagainstfreefloatingcompetitors
AT braunmihaly disentanglingthemechanismssustainingastablestateofsubmergedmacrophytedominanceagainstfreefloatingcompetitors
AT hiltsabine disentanglingthemechanismssustainingastablestateofsubmergedmacrophytedominanceagainstfreefloatingcompetitors