Maximizing the information obtained from chamber-based greenhouse gas exchange measurements in remote areas

Debouk, Haifa; Altimir, Núria; Sebastià, Maria‐Teresa

doi:10.1016/j.mex.2018.07.021

Cited by 6 publications

(11 citation statements)

References 32 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Independent correction schemes have also been developed (Tirol‐Padre et al., 2014; van der Weerden, Clough, & Styles, 2013). Field study has shown that care is needed to get useful quantitative data (Debouk et al., 2018; Nicoloso et al., 2013) The instruments are also sensitive to environmental temperature (Debouk et al., 2018; Rosenstock et al., 2013) and other instrument drifts (Palzer, 2020). Providing that care is taken with deployment, analyzer costs are lower than with many other optical instruments, and portability is good compared with cavity laser spectroscopy.…”

Section: Analysis By Optical and Other Detectorsmentioning

confidence: 99%

“…An increasing variety of N 2 O detectors are available for determining concentrations, either directly in the field in online automatic systems (Grace et al., 2020) or from laboratory analysis of chamber headspace samples stored as described above. A third approach, directed towards maximizing data from campaigns in remote or hill country regions, has been to use manual chambers with a portable field analyzer (Debouk, Altimir, & Sebastià, 2018). This approach is likely to become more common when more portable high‐precision N 2 O analyzers become available.…”

Section: Analytical Systems and Detector Optionsmentioning

confidence: 99%

See 1 more Smart Citation

Global Research Alliance N₂O chamber methodology guidelines: Recommendations for air sample collection, storage, and analysis

et al. 2020

View full text Add to dashboard Cite

Certain aspects in the collection, handling, storage, and subsequent analysis of discrete air samples from non-steady-state flux chambers are critical to generating accurate and unbiased estimates of nitrous oxide (N 2 O) fluxes. The focus of this paper is on air sample collection and storage in small vials (<12 ml) primarily for gas chromatography (GC) analysis. Sample integrity is assured through following simple procedures including storage under pressure and analysis within a few months of collection. Concurrent storage of standards in an identical manner to samples is recommended and allows the storage period to be reliably extended. In the laboratory, an autosampler is typically used in batch analysis of ∼200 sequentially analyzed samples by GC with an electron capture detector (ECD). Some comparisons are given between GC and alternatives including optical N 2 O detectors that are increasingly being used for high-precision N 2 O measurement. The importance of calibration and traceability of gas standards is discussed, where high-quality standards ensure the most accurate assessment of N 2 O concentration and comparability between laboratories. The calibration allows a consistent and best estimate of flux to be derived.

show abstract

Section: Analysis By Optical and Other Detectorsmentioning

confidence: 99%

Section: Analytical Systems and Detector Optionsmentioning

confidence: 99%

Global Research Alliance N₂O chamber methodology guidelines: Recommendations for air sample collection, storage, and analysis

et al. 2020

View full text Add to dashboard Cite

show abstract

“…In the case of CH4 and N2O we did not detect significant differences among measuring conditions. Therefore, we present the average value considering all three measuring conditions [32].…”

Section: Greenhouse Gas Exchange (Ghg) Measurementsmentioning

confidence: 99%

“…Flux measurements, flux calculation and data quality checks were done according to Debouk et al (2018), including a fitting goodness assessment based on the RAdj 2 value, and filtering fluxes below detection limit, calculated as the standard deviation of the ambient concentration over the measuring time. Negative values refer to the flux from the atmosphere to the biosphere and positive values correspond to the flux from the biosphere to the atmosphere, according to the micrometeorological sign convention [33].…”

Section: Greenhouse Gas Exchange (Ghg) Measurementsmentioning

confidence: 99%

Tree – Open Grassland Structure and Composition Drive Greenhouse Gas Exchange in Holm Oak Meadows of the Iberian Peninsula

Ibáñez¹,

Leiva²,

Chocarro³

et al. 2020

Preprint

View full text Add to dashboard Cite

Iberian holm oak meadows are savannah-like ecosystems that result from traditional silvo pastoral practices. However, such traditional uses are declining, driving changes in the typical tree – open grassland structure of these systems. Yet, there are no studies integrating the whole ecosystem — including the arboreal and the herbaceous layer — as drivers of greenhouse gas (GHG: CO2, CH4 and N2O) dynamics. Here we aim at integrating the influence of tree canopies and interactions among plant functional types (PFT: grasses, forbs, and legumes) of the herbaceous layer as GHG exchange drivers. For that purpose, we performed chamber based GHG surveys in plots dominated by representative canopy types of Iberian holm oak meadows, including Quercus species and Pinus pinea stands, the last a common tree plantation replacing traditional stands; and unravelled GHG drivers through a diversity interaction model approach. Our results show that the tree – open grassland structure especially drove CO2 and N2O fluxes, with higher emissions under the canopy than in the open grassland. Emissions under P. pinea canopies being higher than those under Quercus species. In addition, the inclusion of diversity and compositional terms of the herbaceous layer improve the explained variability, legumes enhancing CO2 uptake and N2O emissions. Changes in the tree cover and tree species composition, in combination with changes in the structure and composition of the herbaceous layer, will imply deep changes in the GHG exchange of Iberian holm oak meadows. These results may provide some guidelines to perform better management strategies of this vast but vulnerable ecosystem.

show abstract

“…Besides increasing the statistical power [13] and avoiding the negative effects of long chamber closure time on gas diffusion and microclimate [14,15], this would address the observed high spatial heterogeneity and variability of soil properties in the floodplain [16]. A dynamic closed chamber system that is connected to a portable photoacoustic multi-gas monitor [17,18] meets these requirements and had previously shown its suitability for soil emission measurements in remote areas [19][20][21]. However, the accuracy and precision of (particularly N 2 O) measurements made by the photoacoustic monitor were the subject of earlier discussions [22,23] and should be considered during the interpretation of study results.…”

Section: Introductionmentioning

confidence: 99%

Soil Gaseous Emissions and Partial C and N Balances of Small-Scale Farmer Fields in a River Oasis of Western Mongolia

et al. 2019

View full text Add to dashboard Cite

During the last decades, Mongolian river oases were subjected to an expansion of farmland. Such intensification triggers substantial gaseous carbon (C) and nitrogen (N) losses that may aggravate disequilibria in the soil surface balances of agricultural plots. This study aims to quantify such losses, and assess the implications of these emissions against the background of calculated partial C and N balances. To this end, CO2, NH3, and N2O soil emissions from carrot, hay, and rye plots were measured by a portable dynamic closed chamber system connected to a photoacoustic multi-gas analyzer in six farms of the Mongolian river oasis Bulgan sum center. Average C and N flux rates (1313 g CO2-C ha−1 h−1 to 1774 g CO2-C ha−1 h−1; 2.4 g NH3-N ha−1 h−1 to 3.3 g NH3-N ha−1 h−1; 0.7 g N2O-N ha−1 h−1 to 1.1 g N2O-N ha−1 h−1) and cumulative emissions (3506 kg C ha−1 season−1 to 4514 kg C ha−1 season−1; 7.4 kg N ha−1 season−1 to 10.9 kg N ha−1 season−1) were relatively low compared to those of other agroecosystems, but represented a substantial pathway of losses (86% of total C inputs; 21% of total N inputs). All C and N balances were negative (−1082 kg C ha−1 season−1 to −1606 kg C ha−1 season−1; −27 kg N ha−1 season−1 to −65 kg N ha−1 season−1). To reduce these disequilibria, application of external inputs may need to be intensified whereby such amendments should be incorporated into soil to minimize gaseous emissions.

show abstract

Maximizing the information obtained from chamber-based greenhouse gas exchange measurements in remote areas

Abstract: Graphical abstract

Cited by 6 publications

References 32 publications

Global Research Alliance N₂O chamber methodology guidelines: Recommendations for air sample collection, storage, and analysis

Global Research Alliance N₂O chamber methodology guidelines: Recommendations for air sample collection, storage, and analysis

Tree – Open Grassland Structure and Composition Drive Greenhouse Gas Exchange in Holm Oak Meadows of the Iberian Peninsula

Soil Gaseous Emissions and Partial C and N Balances of Small-Scale Farmer Fields in a River Oasis of Western Mongolia

Contact Info

Product

Resources

About

Maximizing the information obtained from chamber-based greenhouse gas exchange measurements in remote areas

Abstract: Graphical abstract

Cited by 6 publications

References 32 publications

Global Research Alliance N2O chamber methodology guidelines: Recommendations for air sample collection, storage, and analysis

Global Research Alliance N2O chamber methodology guidelines: Recommendations for air sample collection, storage, and analysis

Tree – Open Grassland Structure and Composition Drive Greenhouse Gas Exchange in Holm Oak Meadows of the Iberian Peninsula

Soil Gaseous Emissions and Partial C and N Balances of Small-Scale Farmer Fields in a River Oasis of Western Mongolia

Contact Info

Product

Resources

About

Global Research Alliance N₂O chamber methodology guidelines: Recommendations for air sample collection, storage, and analysis

Global Research Alliance N₂O chamber methodology guidelines: Recommendations for air sample collection, storage, and analysis