Impact of Elevated Atmospheric CO<sub>2</sub> in <i>Spartina maritima</i> Rhizosphere Extracellular Enzymatic Activities
Atmospheric CO<sub>2</sub> enrichment, which is caused to a large extent by anthropogenic activities, is known to interfere with sediment microbial communities via plant rhizospheres. The present work aimed to evaluate this interaction in <i>Spartina maritima</i> ((Curtis) Fe...
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| Format: | Article |
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MDPI AG
2023-07-01
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| Series: | Water |
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| Online Access: | https://www.mdpi.com/2073-4441/15/14/2667 |
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| author | Bernardo Duarte Alexandra Baeta João Carlos Marques Isabel Caçador |
| author_facet | Bernardo Duarte Alexandra Baeta João Carlos Marques Isabel Caçador |
| author_sort | Bernardo Duarte |
| collection | DOAJ |
| description | Atmospheric CO<sub>2</sub> enrichment, which is caused to a large extent by anthropogenic activities, is known to interfere with sediment microbial communities via plant rhizospheres. The present work aimed to evaluate this interaction in <i>Spartina maritima</i> ((Curtis) Fernald.) rhizosediments, aiming to depict the impacts of atmospheric CO<sub>2</sub> increase in the biogeochemical processes occurring in the rhizosphere of this pioneer and highly abundant Mediterranean halophyte. For this purpose, mesocosms trials were conducted, exposing salt marsh cores with <i>S. maritima</i> and its sediments to 410 and 700 ppm of CO<sub>2</sub> while assessing rhizosediment extracellular enzymatic activities. An evident increase in dehydrogenase activity was observed and directly linked to microbial activity, indicating a priming effect in the rhizosphere community under increased CO<sub>2</sub>. Phosphatase showed a marked increase in rhizosediments exposed to elevated CO<sub>2</sub>, denoting a higher requirement of phosphate for maintaining higher biological activity rates. High sulphatase activity suggests a possible S-limitation (microbial or plant) due to elevated CO<sub>2</sub>, probably due to higher sulphur needs for protein synthesis, thus increasing the need to acquire more labile forms of sulphur. With this need to acquire and synthesize amino acids, a marked decrease in protease activity was detected. Most carbon-related enzymes suffered an increase under increased CO<sub>2</sub>. Overall, a shift in sediment extracellular enzymatic activity could be observed upon CO<sub>2</sub> fertilization, mostly due to priming effects and not due to changes in the quality of carbon substrates, as shown by the sediment stable isotope signatures. The altered recycling activity of organic C, N, and P compounds may lead to an unbalance of these biogeochemical cycles, shifting the rhizosphere ecosystem function, with inevitable changes in the ecosystem services level. |
| first_indexed | 2024-03-11T00:33:25Z |
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| institution | Directory Open Access Journal |
| issn | 2073-4441 |
| language | English |
| last_indexed | 2024-03-11T00:33:25Z |
| publishDate | 2023-07-01 |
| publisher | MDPI AG |
| record_format | Article |
| series | Water |
| spelling | doaj.art-9558cb1b34594d9d89e7385d1503b90b2023-11-18T21:48:33ZengMDPI AGWater2073-44412023-07-011514266710.3390/w15142667Impact of Elevated Atmospheric CO<sub>2</sub> in <i>Spartina maritima</i> Rhizosphere Extracellular Enzymatic ActivitiesBernardo Duarte0Alexandra Baeta1João Carlos Marques2Isabel Caçador3MARE—Marine and Environmental Sciences Centre & ARNET—Aquatic Research Network Associated Laboratory, Faculty of Sciences of the University of Lisbon, Campo Grande, 1749-016 Lisbon, PortugalMARE—Marine and Environmental Sciences Centre & ARNET—Aquatic Research Network Associated Laboratory, c/o Department of Zoology, Faculty of Sciences and Technology, University of Coimbra, 3000 Coimbra, PortugalMARE—Marine and Environmental Sciences Centre & ARNET—Aquatic Research Network Associated Laboratory, c/o Department of Zoology, Faculty of Sciences and Technology, University of Coimbra, 3000 Coimbra, PortugalMARE—Marine and Environmental Sciences Centre & ARNET—Aquatic Research Network Associated Laboratory, Faculty of Sciences of the University of Lisbon, Campo Grande, 1749-016 Lisbon, PortugalAtmospheric CO<sub>2</sub> enrichment, which is caused to a large extent by anthropogenic activities, is known to interfere with sediment microbial communities via plant rhizospheres. The present work aimed to evaluate this interaction in <i>Spartina maritima</i> ((Curtis) Fernald.) rhizosediments, aiming to depict the impacts of atmospheric CO<sub>2</sub> increase in the biogeochemical processes occurring in the rhizosphere of this pioneer and highly abundant Mediterranean halophyte. For this purpose, mesocosms trials were conducted, exposing salt marsh cores with <i>S. maritima</i> and its sediments to 410 and 700 ppm of CO<sub>2</sub> while assessing rhizosediment extracellular enzymatic activities. An evident increase in dehydrogenase activity was observed and directly linked to microbial activity, indicating a priming effect in the rhizosphere community under increased CO<sub>2</sub>. Phosphatase showed a marked increase in rhizosediments exposed to elevated CO<sub>2</sub>, denoting a higher requirement of phosphate for maintaining higher biological activity rates. High sulphatase activity suggests a possible S-limitation (microbial or plant) due to elevated CO<sub>2</sub>, probably due to higher sulphur needs for protein synthesis, thus increasing the need to acquire more labile forms of sulphur. With this need to acquire and synthesize amino acids, a marked decrease in protease activity was detected. Most carbon-related enzymes suffered an increase under increased CO<sub>2</sub>. Overall, a shift in sediment extracellular enzymatic activity could be observed upon CO<sub>2</sub> fertilization, mostly due to priming effects and not due to changes in the quality of carbon substrates, as shown by the sediment stable isotope signatures. The altered recycling activity of organic C, N, and P compounds may lead to an unbalance of these biogeochemical cycles, shifting the rhizosphere ecosystem function, with inevitable changes in the ecosystem services level.https://www.mdpi.com/2073-4441/15/14/2667extracellular enzymatic activitiesrhizospherestable isotope analysissalt marsh |
| spellingShingle | Bernardo Duarte Alexandra Baeta João Carlos Marques Isabel Caçador Impact of Elevated Atmospheric CO<sub>2</sub> in <i>Spartina maritima</i> Rhizosphere Extracellular Enzymatic Activities Water extracellular enzymatic activities rhizosphere stable isotope analysis salt marsh |
| title | Impact of Elevated Atmospheric CO<sub>2</sub> in <i>Spartina maritima</i> Rhizosphere Extracellular Enzymatic Activities |
| title_full | Impact of Elevated Atmospheric CO<sub>2</sub> in <i>Spartina maritima</i> Rhizosphere Extracellular Enzymatic Activities |
| title_fullStr | Impact of Elevated Atmospheric CO<sub>2</sub> in <i>Spartina maritima</i> Rhizosphere Extracellular Enzymatic Activities |
| title_full_unstemmed | Impact of Elevated Atmospheric CO<sub>2</sub> in <i>Spartina maritima</i> Rhizosphere Extracellular Enzymatic Activities |
| title_short | Impact of Elevated Atmospheric CO<sub>2</sub> in <i>Spartina maritima</i> Rhizosphere Extracellular Enzymatic Activities |
| title_sort | impact of elevated atmospheric co sub 2 sub in i spartina maritima i rhizosphere extracellular enzymatic activities |
| topic | extracellular enzymatic activities rhizosphere stable isotope analysis salt marsh |
| url | https://www.mdpi.com/2073-4441/15/14/2667 |
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