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We tested the hypothesis that carbon dioxide (CO2) uptake fluxes in coastal salt marshes follow ecological similitudes (parameter reductions) and distinct environmental regimes. The hypothesis was evaluated utilizing data from four salt marshes in Waquoit Bay, MA, USA collected during May-October 2013. Using dimensional analysis method from fluid mechanics and engineering, we reduced five flux and ecological variables (CO2 uptake, light, soil temperature, salinity, and atmospheric pressure) into two mechanistically meaningful dimensionless groups: (a) light use efficiency number (LUE = CO2 uptake normalized by daylight) and (b) biogeochemical number (BGC = interactions among soil temperature, salinity, and atmospheric pressure). Graphical exploration of the dimensionless numbers with the observed data revealed an emergent pattern that was distinctly characterized by high, transitional, and low LUE regimes. Transitions among the identified regimes were dictated by thresholds of soil temperature and salinity. Low LUE regime corresponded to unfavorable environmental conditions (soil temperature 17C and salinity > 30ppt), whereas high LUE regime was governed by favorable conditions (soil temperature > 17C and salinity 30ppt). The identified emergent pattern and environmental thresholds would provide key insights into the underlying organizing principles of CO2 uptake and the major environmental drivers in coastal salt marshes.
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Ecological parameter reductions, environmental regimes, and characteristic process diagram of carbon dioxide fluxes in coastal salt marshes
Abstract We investigated the ecological parameter reductions (termed “similitudes”) and characteristic patterns of the net uptake fluxes of carbon dioxide (CO 2 ) in coastal salt marshes using dimensional analysis method from fluid mechanics and hydraulic engineering. Data collected during May–October, 2013 from four salt marshes in Waquoit Bay and adjacent estuary, Massachusetts, USA were utilized to evaluate the theoretically-derived dimensionless flux and various ecological driver numbers. Two meaningful dimensionless groups were discovered as the light use efficiency number (LUE = CO 2 normalized by photosynthetically active radiation) and the biogeochemical number (combination of soil temperature, porewater salinity, and atmospheric pressure). A semi-logarithmic plot of the dimensionless numbers indicated the emergence of a characteristic diagram represented by three distinct LUE regimes (high, transitional, and low). The high regime corresponded to the most favorable (high temperature and low salinity) condition for CO 2 uptake, whereas the low regime represented an unfavorable condition (low temperature and high salinity). The analysis identified two environmental thresholds (soil temperature ~ 17 °C and salinity ~ 30 ppt), which dictated the regime transitions of CO 2 uptake. The process diagram and critical thresholds provide important insights into the CO 2 uptake potential of coastal wetlands in response to changes in key environmental drivers.
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- Award ID(s):
- 1705941
- PAR ID:
- 10194991
- Date Published:
- Journal Name:
- Scientific Reports
- Volume:
- 10
- Issue:
- 1
- ISSN:
- 2045-2322
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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We tested the hypothesis that carbon dioxide (CO2) uptake fluxes in coastal salt marshes follow ecological similitudes (parameter reductions) and distinct environmental regimes. The hypothesis was evaluated utilizing data from four salt marshes in Waquoit Bay, MA, USA collected during May-October 2013. Using dimensional analysis method from fluid mechanics and engineering, we reduced five flux and ecological variables (CO2 uptake, light, soil temperature, salinity, and atmospheric pressure) into two mechanistically meaningful dimensionless groups: (a) light use efficiency number (LUE = CO2 uptake normalized by daylight) and (b) biogeochemical number (BGC = interactions among soil temperature, salinity, and atmospheric pressure). Graphical exploration of the dimensionless numbers with the observed data revealed an emergent pattern that was distinctly characterized by high, transitional, and low LUE regimes. Transitions among the identified regimes were dictated by thresholds of soil temperature and salinity. Low LUE regime corresponded to unfavorable environmental conditions (soil temperature 17C and salinity > 30ppt), whereas high LUE regime was governed by favorable conditions (soil temperature > 17C and salinity 30ppt). The identified emergent pattern and environmental thresholds would provide key insights into the underlying organizing principles of CO2 uptake and the major environmental drivers in coastal salt marshes.more » « less
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.1038/s41598-020-72066-8
