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To understand patterns in CO2 partial pressure (PCO2) over time in wetlands’ surface water and porewater, we examined the relationship between PCO2 and land–atmosphere flux of CO2 at the ecosystem scale at 22 Northern Hemisphere wetland sites synthesized through an open call. Sites spanned 6 major wetland types (tidal, alpine, fen, bog, marsh, and prairie pothole/karst), 7 Köppen climates, and 16 different years. Ecosystem respiration (Reco) and gross primary production (GPP), components of vertical CO2 flux, were compared to PCO2, a component of lateral CO2 flux, to determine if photosynthetic rates and soil respiration consistently influence wetland surface and porewater CO2 concentrations across wetlands. Similar to drivers of primary productivity at the ecosystem scale, PCO2 was strongly positively correlated with air temperature (Tair) at most sites. Monthly average PCO2 tended to peak towards the middle of the year and was more strongly related to Reco than GPP. Our results suggest Reco may be related to biologically driven PCO2 in wetlands, but the relationship is site-specific and could be an artifact of differently timed seasonal cycles or other factors. Higher levels of discharge do not consistently alter the relationship between Reco and temperature normalized PCO2. This work synthesizes relevant data and identifies key knowledge gaps in drivers of wetland respiration.
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Allequash Creek Wetland Half-Hourly Soil Porewater PCO2 2021
Dissolved CO2, also known as PCO2, was continuously measured in parts per million in soil porewater in a riverine fen in Northern Wisconsin near the eddy covariance flux tower positioned there, named the Allequash Creek Wetland Site (US-ALQ) on AmeriFlux. The site is also a North Temperate Lakes (NTL) LTER study site. This data package contains half-hourly averages of PCO2 from March 24th to October 25th, 2021. This data package is complete but data collection may be reinstated in the future.
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- Award ID(s):
- 2025982
- PAR ID:
- 10492858
- Publisher / Repository:
- Environmental Data Initiative
- Date Published:
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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