Continuous Measurement of Diffusive and Ebullitive Fluxes of Methane in Aquatic Ecosystems by an Open Dynamic Chamber Method

Gerardo-Nieto, Oscar; Vega-Peñaranda, Abner; Gonzalez-Valencia, Rodrigo; Alfano-Ojeda, Yameli; Thalasso, Frédéric

doi:10.1021/acs.est.9b00425

Cited by 14 publications

(22 citation statements)

References 46 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…However, we propose that GHG emissions from reservoirs need future research efforts due to their large spatiotemporal variations, i.e., conducting more field measurements of GHG emissions from reservoirs worldwide (e.g., diffusive/ebullitive fluxes from surface water, as well as downstream degassing covering seasonal scale) and in the long term so as to establish the impact of the trophic state of reservoirs on GHG emissions (DelSontro et al, 2018;Beaulieu et al, 2019). For such a worldwide effort, installing continuous measurement systems for monitoring of GHG emissions would be appreciated (Gerardo-Nieto et al, 2019).…”

Section: Discussionmentioning

confidence: 99%

Long-Term Evolution of Greenhouse Gas Emissions From Global Reservoirs

Yan

Thieu

Garnier

2021

Front. Environ. Sci.

View full text Add to dashboard Cite

The contribution of artificial reservoirs to greenhouse gas (GHG) emissions has been emphasized in previous studies. In the present study, we collected and updated data on GHG emission rates from reservoirs at the global scale, and applied a new classification method based on the hydrobelt concept. Our results showed that CH4 and CO2 emissions were significantly different in the hydrobelt groups (p < 0.01), while no significant difference was found for N2O emissions, possibly due to their limited measurements. We found that annual GHG emissions (calculated as C or N) from global reservoirs amounted to 12.9 Tg CH4-C, 50.8 Tg CO2-C, and 0.04 Tg N2O-N. Furthermore, GHG emissions (calculated as CO2 equivalents) were also estimated for the 1950–2017 period based on the cumulative number and surface area of global reservoirs in the different hydrobelts. The highest increase rate in both the number of reservoirs and their surface area, which occurred from 1950 to the 1980s, led to an increase in GHG emissions from reservoirs. Since then, the increase rate of reservoir construction, and hence GHG emissions, has slowed down. Moreover, we also examined the potential impact of reservoir eutrophication on GHG emissions and found that GHG emissions from reservoirs could increase by 40% under conditions in which total phosphorus would double. In addition, we showed that the characteristics of reservoirs (e.g., geographical location) and their catchments (e.g., surrounding terrestrial net primary production, and precipitation) may influence GHG emissions. Overall, a major finding of our study was to provide an estimate of the impact of large reservoirs during the 1950–2017 period, in terms of GHG emissions. This should help anticipate future GHG emissions from reservoirs considering all reservoirs being planned worldwide. Besides using the classification per hydrobelt and thus reconnecting reservoirs to their watersheds, our study further emphasized the efforts to be made regarding the measurement of GHG emissions in some hydrobelts and in considering the growing number of reservoirs.

show abstract

Section: Discussionmentioning

confidence: 99%

Long-Term Evolution of Greenhouse Gas Emissions From Global Reservoirs

Yan

Thieu

Garnier

2021

Front. Environ. Sci.

View full text Add to dashboard Cite

show abstract

“…Similarly, from the abrupt C C increases, the CH 4 content of the bubbles (M B ) and their size (d B ) was determined, which is a potential additional benefit of the MOD chamber. These parameters are indeed the most important parameters that affect ebullitive CH 4 transport through the water column and to the atmosphere (DelSontro et al, 2015;Greene et al, 2014). Overall, M B ranged from 1.23 to 781 mg CH 4 with a mean of 81 ± 144 mg CH 4 .…”

Section: Resultsmentioning

confidence: 95%

Technical note: Mobile open dynamic chamber measurement of methane macroseeps in lakes

Thalasso

Anthony

Irzak³

et al. 2020

Hydrol. Earth Syst. Sci.

Self Cite

View full text Add to dashboard Cite

Abstract. Methane (CH4) seepage (i.e., steady or episodic flow of gaseous hydrocarbons from subsurface reservoirs) has been identified as a significant source of atmospheric CH4. However, radiocarbon data from polar ice cores have recently brought into question the magnitude of fossil CH4 seepage naturally occurring. In northern high latitudes, seepage of subsurface CH4 is impeded by permafrost and glaciers, which are under an increasing risk of thawing and melting in a globally warming world, implying the potential release of large stores of CH4 in the future. Resolution of these important questions requires a better constraint and monitoring of actual emissions from seepage areas. The measurement of these seeps is challenging, particularly in aquatic environments, because they involve large and irregular gas flow rates, unevenly distributed both spatially and temporally. Large macroseeps are particularly difficult to measure due to a lack of lightweight, inexpensive methods that can be deployed in remote Arctic environments. Here, we report the use of a mobile chamber for measuring emissions at the surface of ice-free lakes subject to intense CH4 macroseepage. Tested in a remote Alaskan lake, the method was validated for the measurement of fossil CH4 emissions of up to 1.08 × 104 g CH4 m−2 d−1 (13.0 L m−2 min−1 of 83.4 % CH4 bubbles), which is within the range of global fossil methane seepage and several orders of magnitude above standard ecological emissions from lakes. In addition, this method allows for low diffusive flux measurements. Thus, the mobile chamber approach presented here covers the entire magnitude range of CH4 emissions currently identified, from those standardly observed in lakes to intense macroseeps, with a single apparatus of moderate cost.

show abstract

“…Measurements of CO 2 and CH 4 flux (release and uptake) were taken in situ using a Los Gatos ultra-portable greenhouse gas analyzer (UGGA) with a closed-collar dark chamber method (Figure 2; Van Huissteden et al, 2011;Musarika et al, 2017). The UGGA reports measurements of CO 2 and CH 4 using cavity enhanced absorption techniques (Baer et al, 2002;Gerardo-Nieto et al, 2019). Each chamber collar (30 cm diameter, 55 cm height, 35 L volume) was made of PVC coupled with a PVC lid.…”

Section: Co 2 and Ch 4 Flux Measurementsmentioning

confidence: 99%

Reducing Emissions From Degraded Floodplain Wetlands

Limpert

Carnell

Trevathan-Tackett

et al. 2020

Front. Environ. Sci.

View full text Add to dashboard Cite

Globally, freshwater wetlands are significant carbon sinks; however, altering a wetland's hydrology can reduce its ability to sequester carbon and may lead to the release of previously stored soil carbon. Rehabilitating a wetland's water table has the potential to restore the natural process of wetland soil carbon sequestration and storage. Further, little is known about the role of microbial communities that mediate carbon cycling during wetland rehabilitation practices. Here, we examined the carbon emissions and microbial community diversity during a wetland rehabilitation process known as "environmental watering" (rewetting) in an Australian, semi-arid freshwater floodplain wetland. By monitoring carbon dioxide (CO 2 ) and methane (CH 4 ) emissions during dry and wet phases of an environmental watering event, we determined that adding water to a degraded semi-arid floodplain wetland reduces carbon emissions by 28-84%. The watering event increased anoxic levels and plant growth in the aquatic zone of the wetland, which may correlate with lower carbon emissions during and after environmental watering due to lower anaerobic microbial decomposition processes and higher CO 2 sequestration by vegetation. During the watering event, areas with higher inundation had lower CO 2 emissions (5.15 ± 2.50 g CO 2 m −2 day −1 ) compared to fringe areas surrounding the wetland (11.89 ± 4.25 g CO 2 m −2 day −1 ). CH 4 flux was inversely correlated with CO 2 emissions during inundation periods, showing a 38% (0.013 ± 0.061 g CO 2 -e m −2 day −1 ) increase when water was present in the wetland. During the dry phases of environmental watering, there was CH 4 uptake within the fringe and aquatic zones (−0.013 ± 0.063 g CO 2 -e m −2 day −1 ). A clear succession of soil microbial community was observed during the dry-wet phases of the environmental watering process. This suggests that wetland hydrology plays a large role in the microbial community structure of these wetland ecosystems, and is consequently linked to CO 2 and CH 4 emissions. Overall, the total carbon emissions (CO 2 + CH 4 ) were reduced within the wetland during and after the environmental watering event, due to increasing vegetative growth and subsequent CO 2 sequestration. We, therefore, recommend environmental watering practices in this degraded arid wetland ecosystem to improve conditions for wetland carbon sequestration and storage. Further use of this management practice may improve wetland carbon storage across other arid freshwater wetland ecosystems with similar hydrologic regimes.

show abstract

Continuous Measurement of Diffusive and Ebullitive Fluxes of Methane in Aquatic Ecosystems by an Open Dynamic Chamber Method

Cited by 14 publications

References 46 publications

Long-Term Evolution of Greenhouse Gas Emissions From Global Reservoirs

Long-Term Evolution of Greenhouse Gas Emissions From Global Reservoirs

Technical note: Mobile open dynamic chamber measurement of methane macroseeps in lakes

Reducing Emissions From Degraded Floodplain Wetlands

Contact Info

Product

Resources

About