Redistribution of methane emission hot spots under drawdown conditions

Hilgert, Stephan; Fernandes, Cristóvão Vicente Scapulatempo; Fuchs, Stéphan

doi:10.1016/j.scitotenv.2018.07.338

Cited by 19 publications

(15 citation statements)

References 58 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Features of the GRTS design that make it particularly well suited for estimating CH 4 ‐E and CH 4 ‐T include (1) a spatially balanced distribution of sampling sites (Olsen et al, 2012), thereby better representing the full range of environmental conditions present within a waterbody as compared to random sampling, and (2) the ability to utilize spatial autocorrelation to better constrain variance estimates. In this study, variance estimates were reduced by 23% when spatial autocorrelation was incorporated into the estimate, indicating strong spatial autocorrelation in CH 4 ‐T, as has been reported elsewhere (Beaulieu et al, 2016; Hilgert et al, 2019). The median 95% confidence intervals for CH 4 ‐T and CO 2 ‐T were 72.3% and 58.2% of the mean emission rate, respectively.…”

Section: Discussionsupporting

confidence: 83%

“…Journal of Geophysical Research: Biogeosciences autocorrelation in CH 4 -T, as has been reported elsewhere (Beaulieu et al, 2016;Hilgert et al, 2019). The median 95% confidence intervals for CH 4 -T and CO 2 -T were 72.3% and 58.2% of the mean emission rate, respectively.…”

Section: 1029/2019jg005474supporting

confidence: 82%

“…Sampling tributary‐associated areas at a higher density than open‐water areas allowed for a better constrained and more accurate population estimate than if the entire waterbody had been sampled at a uniform density. Other studies have attributed tributary associated CH 4 hots spots to higher temperatures at the sediment‐water interface, high sediment deposition rates, and sustained nutrient inputs from inflowing rivers which support phytoplankton, a source of particularly labile carbon for methanogens (De Mello et al, 2018; DelSontro et al, 2011; Grinham et al, 2011; Hilgert et al, 2019; Musenze et al, 2014; Sturm et al, 2014). Low water depths in tributary areas minimizes the dissolution of bubbles during vertical transport through the water column, further enhancing CH 4 emissions (McGinnis et al, 2006).…”

Section: Discussionmentioning

confidence: 99%

See 2 more Smart Citations

Methane and Carbon Dioxide Emissions From Reservoirs: Controls and Upscaling

et al. 2020

View full text Add to dashboard Cite

Estimating carbon dioxide (CO 2) and methane (CH 4) emission rates from reservoirs is important for regional and national greenhouse gas inventories. A lack of methodologically consistent data sets for many parts of the world, including agriculturally intensive areas of the United States, poses a major challenge to the development of models for predicting emission rates. In this study, we used a systematic approach to measure CO 2 and CH 4 diffusive and ebullitive emission rates from 32 reservoirs distributed across an agricultural to forested land use gradient in the United States. We found that all reservoirs were a source of CH 4 to the atmosphere, with ebullition being the dominant emission pathway in 75% of the systems. Ebullition was a negligible emission pathway for CO 2 , and 65% of sampled reservoirs were a net CO 2 sink. Boosted regression trees (BRTs), a type of machine learning algorithm, identified reservoir morphology and watershed agricultural land use as important predictors of emission rates. We used the BRT to predict CH 4 emission rates for reservoirs in the U.S. state of Ohio and estimate they are the fourth largest anthropogenic CH 4 source in the state. Our work demonstrates that CH 4 emission rates for reservoirs in our study region can be predicted from information in readily available national geodatabases. Expanded sampling campaigns could generate the data needed to train models for upscaling in other U.S. regions or nationally. ©2020. American Geophysical Union. This article has been contributed to by US Government employees and their work is in the public domain in the USA.

show abstract

Section: Discussionsupporting

confidence: 83%

Section: 1029/2019jg005474supporting

confidence: 82%

Section: Discussionmentioning

confidence: 99%

See 1 more Smart Citation

Methane and Carbon Dioxide Emissions From Reservoirs: Controls and Upscaling

et al. 2020

View full text Add to dashboard Cite

show abstract

“…Previous studies have shown that lake or reservoir CH 4 ebullition can peak at certain points in space ("hot spots") or time ("hot moments"). Hot spots were predominantly found in shallow areas (Ostrovsky 2003;Grinham et al 2011;Zheng et al 2011;Deshmukh et al 2014;Natchimuthu et al 2016;de Mello et al 2018), in areas close to tributary river inflows (DelSontro et al 2011;Zhao et al 2013;Musenze et al 2014;Beaulieu et al 2016;Descloux et al 2017;Harrison et al 2017;Tušer et al 2017;de Mello et al 2018;Hilgert et al 2019), and in areas with high sediment accumulation (Sobek et al 2012;Maeck et al 2013;Hilgert et al 2019), high organic carbon content (Grinham et al 2018;Hilgert et al 2019), or high organic matter reactivity (Sobek et al 2012). Hot moments of ebullition tend to correlate positively with air temperature (Delsontro et al 2010;Maeck et al 2013;Wik et al 2013;Peixoto et al 2015;Wilkinson et al 2015;Natchimuthu et al 2016), bottom water temperature (Deshmukh et al 2014), sediment temperature (Tušer et al 2017), low hydrostatic pressure (Ostrovsky 2003;Varadharajan and Hemond 2012;Wik et al 2013;Deshmukh et al 2014;Harrison et al 2017;Grinham et al 2018), and low air pressure (Mattson and Likens 1990;Deshmukh et al 2014;…”

mentioning

confidence: 99%

“…While there are a number of studies that measured CH 4 ebullition in reservoirs at low latitudes, both in the tropics (Keller and Stallard 1994;Abril et al 2005;Ramos et al 2006;DelSontro et al 2011;de Mello et al 2018) and subtropics (Grinham et al 2011;Deshmukh et al 2014;Beaulieu et al 2016;Guérin et al 2016;Grinham et al 2018;Yang et al 2018;Hilgert et al 2019;Marcon et al 2019), only a few of them (Keller and Stallard 1994;Deshmukh et al 2014;Yang et al 2018;Marcon et al 2019) have studied temporal trends of ebullition in enough detail to identify seasonal trends. None of these studies have systematically compared the magnitude of the variability of CH 4 ebullition over scales of both space and time.…”

mentioning

confidence: 99%

Comparing methane ebullition variability across space and time in a Brazilian reservoir

Linkhorst

Hiller

DelSontro

et al. 2020

Limnology & Oceanography

View full text Add to dashboard Cite

The potent greenhouse gas methane (CH 4 ) is readily emitted from tropical reservoirs, often via ebullition (bubbles). This highly stochastic emission pathway varies in space and time, however, hampering efforts to accurately assess total CH 4 emissions from water bodies. We systematically studied both the spatial and temporal scales of ebullition variability in a river inflow bay of a tropical Brazilian reservoir. We conducted multiple highly resolved spatial surveys of CH 4 ebullition using a hydroacoustic approach supplemented with bubble traps over a 12-month and a 2-week timescale to evaluate which scale of variation was more important. To quantify the spatial and temporal variability of CH 4 ebullition, we used the quartile coefficients of dispersion at each point in space and time and compared their frequency distributions across the various temporal and spatial scales. We found that CH 4 ebullition varied more temporally than spatially and that the intra-annual variability was stronger than daily variability within 2 weeks. We also found that CH 4 ebullition was positively related to water temperature increase and pressure decrease, but no consistent relationship with water column depth or sediment characteristics was found, further highlighting that temporal drivers of emissions were stronger than spatial drivers. Annual estimates of CH 4 ebullition from our study area may vary by 75-174% if ebullition is not resolved in time and space, but at a minimum we recommend conducting spatially resolved measurements at least once during each major hydrologic season in tropical regions (i.e., in dry and rainy season when water levels are falling and rising, respectively).

show abstract

Spatial and temporal heterogeneity of methane ebullition in lowland headwater streams and the impact on sampling design

Robison

Wollheim

Turek

et al. 2021

Limnology & Oceanography

View full text Add to dashboard Cite

Headwater streams are known sources of methane (CH 4 ) to the atmosphere, but their contribution to global scale budgets remains poorly constrained. While efforts have been made to better understand diffusive fluxes of CH 4 in streams, much less attention has been paid to ebullitive fluxes. We examine the temporal and spatial heterogeneity of CH 4 ebullition from four lowland headwater streams in the temperate northeastern United States over a 2-yr period. Ebullition was observed in all monitored streams with an overall mean rate of 1.00 AE 0.23 mmol CH 4 m À2 d À1 , ranging from 0.01 to 1.79 to mmol CH 4 m À2 d À1 across streams. At biweekly timescales, rates of ebullition tended to increase with temperature. We observed a high degree of spatial heterogeneity in CH 4 ebullition within and across streams. Yet, catchment land use was not a simple predictor of this heterogeneity, and instead patches scale variability weakly explained by water depth and sediment organic matter content and quality. Overall, our results support the prevalence of CH 4 ebullition from streams and high levels of variability characteristic of this process. Our findings also highlight the need for robust temporal and spatial sampling of ebullition in lotic ecosystems to account for this high level of heterogeneity, where multiple sampling locations and times are necessary to accurately represent the mean rate of flux in a stream. The heterogeneity observed likely indicates a complex set of drivers affect CH 4 ebullition from streams which must be considered when upscaling site measurements to larger spatial scales.

show abstract

Redistribution of methane emission hot spots under drawdown conditions

Cited by 19 publications

References 58 publications

Methane and Carbon Dioxide Emissions From Reservoirs: Controls and Upscaling

Methane and Carbon Dioxide Emissions From Reservoirs: Controls and Upscaling

Comparing methane ebullition variability across space and time in a Brazilian reservoir

Spatial and temporal heterogeneity of methane ebullition in lowland headwater streams and the impact on sampling design

Contact Info

Product

Resources

About