Due to the simultaneous influence of various environmental drivers and management activities (e.g. fertilizer application, harvest, grazing) the flux patterns are often complex and difficult to attribute to individual drivers. Moreover, management related mitigation options may often result in trade-offs between different GHG or between emission of GHG and reactive gases like NH3, NOx, or VOCs. To investigate these interactions, the session addresses experimentalists and modelers working on carbon and nitrogen cycling processes and related fluxes on plot, field, landscape, and regional scale. It is open to a wide range of studies including the development and application of new devices, methods, and model approaches as well as field observations and process studies. Particularly welcome are studies on multiple gases and on the full carbon, nitrogen or GHG budgets. We also encourage contributions about the applicability and overall potential of mitigation options.
Orals: Mon, 4 May, 08:30–10:15 | Room 1.31/32
Nitrous oxide (N2O) emissions are a major contributor to the greenhouse gas footprint of agricultural systems and are strongly influenced by nitrogen management. With the ongoing expansion and specialization of organic farming in Germany, an increasing number of farms operate without livestock, raising new challenges for nutrient supply. In stockless organic systems, clover grass is used in alternative ways instead of animal feed, resulting in different organic fertilizer forms with contrasting nitrogen availability, which may strongly affect N2O emissions. However, field-based empirical data on these effects are still scarce.
This study assessed N2O emissions from potato cultivation within a long-term organic field experiment established in 2017 at the experimental farm of the University of Kassel, Germany. The experiment compares different organic farm types and fertilization strategies, with a focus on stockless systems. During the 2024 growing season (May–September), N2O fluxes were measured in three farm types using dynamic, non-transparent PVC chambers installed on permanently embedded soil frames. Chambers were equipped with internal fans, temperature sensors, vent, and pressure opening to ensure stable measurement conditions. In addition to ridge measurements, small PVC sampling tubes installed between ridges allowed spatially differentiated flux measurements across ridge and inter-ridge positions. Chamber air was continuously analyzed in real time using laser-based direct absorption spectroscopy (MIRA Ultra N2O/CO2, AERIS Technologies, USA).
The investigated systems included (i) a bio-vegan Cut & Carry system fertilized with tofu whey and fresh clover grass mulch, (ii) a soil fertility–oriented system fertilized with clover grass compost, and (iii) a mixed-farm system fertilized with cattle manure compost, with nitrogen application rates ranging from 55 to 67 kg N ha-1. Across all systems, N2O emissions exhibited pronounced temporal dynamics, with the highest fluxes occurring after spring fertilization, incorporation of organic fertilizers, and mechanical disturbance such as ridge harrowing. Additional emission peaks were observed after ridging operations and after harvest.
Cumulative N2O emissions over the growing season were consistently higher on ridges than between ridges (42.7 %). The bio-vegan Cut & Carry treatment showed the highest cumulative N2O emissions (average across on- and between ridge positions: 85 mg m-2), attributed to rapidly available nitrogen from tofu whey combined with fresh clover grass mulch. In contrast, compost-based fertilization strategies resulted in lower emissions (average across on- and between ridge positions: 53–60 mg m-2), likely due to higher C/N ratios and slower nitrogen release. Despite these differences, potato yields did not differ significantly among systems.
The results demonstrate that rapid nitrogen availability in stockless organic systems can substantially increase N2O losses without providing yield benefits. Compost-based fertilization strategies appear more effective in mitigating N2O emissions while maintaining productivity, highlighting the importance of carefully designed clover grass utilization and nutrient transfer strategies for climate mitigation in stockless organic farming systems.
How to cite: Möller, M., Schlotter, D., Bruns, C., and Athmann, M.: Rapid Nitrogen Supply Increases N2O Losses in Organic Potato Systems, EGU General Assembly 2026, Vienna, Austria, 3–8 May 2026, EGU26-1786, https://doi.org/10.5194/egusphere-egu26-1786, 2026.
Agricultural ecosystems are significant contributors to greenhouse gas (GHG) emissions, yet they also offer mitigation potential through soil carbon sequestration and improved nutrient management. However, field-based assessments of major GHG emissions (e.g., CO2 and N2O) remain scarce in croplands in sub-Saharan African (SSA), limiting the development of region-specific mitigation strategies. Process-based crop-soil models can complement experimental studies by explicitly representing the biogeochemical processes controlling gas fluxes and by assessing the impacts of management practices.
In this study, we applied the STICS (Simulateur mulTIdisciplinaire pour les Cultures Standard, (Brisson et al., 2003)) soil-crop model to simulate soil CO2 and N2O emissions at two experimental sites in Zimbabwe: the Domboshava Training Centre (DTC; abruptic lixisols), and the University of Zimbabwe Farm (UZF; xanthic ferralsols). The model represents key processes governing CO2 and N2O production from soil, including decomposition, nitrification, and denitrification, as well as their main environmental drivers (soil temperature, water-filled pore space, ammonium and nitrate availability). Model outputs were evaluated against field GHG measurements done between 2019 and 2021 at both sites across six treatments, each replicated four times: conventional tillage, conventional tillage with rotation, no-tillage, no-tillage with mulch, no-tillage with rotation, no-tillage with mulch and rotation. Soil CO2 emissions were simulated by combining STICS-simulated heterotrophic respiration with an independent autotrophic respiration module accounting for root respiration. After calibration, the model reproduced the main environmental drivers of soil CO2 and N2O emissions reasonably well. The simulated and measured soil CO2 emissions showed moderate agreement at the daily scale (R2 = 0.40, RMSE = 18.1 kg C ha-1 d-1, EF = 0.28) and strong agreement for cumulative emissions (R2 = 0.87, RMSE = 800.74 kg C ha-1, EF = 0.84). Simulated N2O emissions were of the same order of magnitude as the observations across all treatments (observed range: 0-0.0126 kg N ha-1 d-1; simulated range: 0-0.0132 kg N ha-1 d-1). However, both daily and cumulative emissions were overestimated across treatments, particularly during the 2020-2021 season at UZF, potentially reflecting missed short-lived emission pulses due to non-continuous measurements. Across all treatments, simulated and observed mean seasonal N2O emissions ranged from 0.155 to 0.580 kg N ha-1 and 0.154 to 0.285 kg N ha-1, respectively (R2 = 0.15, RMSE = 0.18 kg N ha-1, EF = -3.26). Overall, this modelling framework provides a useful tool to further explore the effects of crop management practices on GHG emissions in cropping systems in SSA.
How to cite: Agbohessou, Y. F., Shumba, A., Diop, S., Civil, J.-A., Falconnier, G. N., Couëdel, A., Chikowo, R., Corbeels, M., Six, J., Thierfelder, C., and Cardinael, R.: Simulating CO2 and N2O emissions from sub-Saharan African croplands under conservation agriculture , EGU General Assembly 2026, Vienna, Austria, 3–8 May 2026, EGU26-9109, https://doi.org/10.5194/egusphere-egu26-9109, 2026.
Grasslands play a crucial role in the global carbon cycle, yet their greenhouse gas (GHG) dynamics are highly sensitive to environmental fluctuations, especially in flood-prone systems. This study provides a full year of continuous CO₂ and high-resolution CH₄ Eddy Covariance flux measurements from a seasonally flooded and grazed floodplain grassland in Marchegg, Austria – offering a rare insight into how repeated inundation events shape the net carbon balance.
In 2024, the grassland functioned as a modest net carbon sink (–17.6 g C-CO₂ eq m⁻² yr⁻¹). Annual CO₂ uptake (–27.3 g C m⁻² yr⁻¹) was dampened by reduced photosynthesis during floods, while CH₄ emissions (1.6 g C m⁻² yr⁻¹) increased sharply and predictably with each inundation. These flood-related CH₄ pulses, captured at high temporal resolution, accounted for the majority of annual CH₄ release and strongly influenced the overall carbon budget. Whereas CO₂ exchange was primarily driven by light availability and vegetation greenness, CH₄ fluxes were almost entirely controlled by soil moisture and standing water presence, showing minimal response to grazing. The timing of flood events within the growing season proved to be critical. Both early- and mid-season inundation substantially reduced CO₂ uptake, whereas late-season flooding had only a minimal impact. Inundation also triggered pronounced methane emission hot moments, underscoring the dominant role of hydrology in controlling annual greenhouse gas fluxes.
Overall, these findings demonstrate that flood events are the primary determinant of the annual GHG balance in this grassland ecosystem. They further highlight the necessity of year-round, multi-gas monitoring to accurately capture carbon dynamics in hydrologically variable systems. In addition, the results emphasize that adaptive management practices—such as water level regulation, grazing timing, and land-use planning—are crucial for mitigating GHG emissions and enhancing ecosystem resilience under increasingly variable hydrological conditions.
How to cite: Lindenberger, A., Rauch, H. P., Kasak, K., Pindus, M., and von der Thannen, M.: Carbon Flux Dynamics in a Flood-Prone Grassland: Linking CO₂ Uptake and CH₄ Emission Pulses, EGU General Assembly 2026, Vienna, Austria, 3–8 May 2026, EGU26-2766, https://doi.org/10.5194/egusphere-egu26-2766, 2026.
Agricultural soils represent a significant source of greenhouse gas (GHG) emissions at the global scale, with nitrous oxide (N2O) playing a major role. Promoting more sustainable agricultural practices is not only essential for climate change adaptation, but also for mitigating emissions from agriculturally used soils. Several management measures may contribute to both mitigation and adaptation, including long-term low-intensity tillage systems. When combined with other management measures associated with regenerative agriculture, such as intensive intercropping and undersowing, compost and mulch applications, and the use of biostimulants, their effects on N2O emissions are poorly understood. The objective of this study was to assess the impact of these management practices on soil N2O emissions.
Since 2010, the factors tillage, compost, and mulching, and since 2020 the factor vitalization (compost tea and ferments), have been implemented in a split-plot design with fourfold repetition in an organically managed long-term field experiment on a Luvisol in central Germany. Five treatments ranging from conventional ploughing to progressively intensified regenerative management (reduced tillage, reduced tillage with compost, reduced tillage with compost and mulch, and reduced tillage with compost, mulch, and vitalization) were selected for weekly N2O flux measurements (closed static chamber method). Emissions were monitored from October 2021 to October 2023, covering winter intercrop vetch-triticale, potato cultivation, and a winter wheat-pea mixture. During potato cropping, reduced tillage plots were tilled to a depth of 0.12 m prior to planting, and mulching was applied as dead mulch (green rye, C:N ratio of 39:1). Living mulch was established in the winter wheat-pea mixture as an undersown crop (clover and ryegrass).
Cumulative emissions (728 days) were 9.28 (standard error: ±0.78) kg N2O-N ha-1 in the ploughed control treatment, whereas reduced tillage without additional factor combination resulted in slightly lower emissions of 8.06 (±0.53) kg N2O-N ha-1. Compost application with reduced tillage promoted slightly higher emissions compared to the ploughed control with 10.20 (±0.75) kg N2O-N ha-1. However, the combination of reduced tillage, compost, and mulching significantly reduced emissions compared to reduced tillage with compost alone, resulting in 6.90 (±0.35) kg N2O-N ha-1. The factor vitalization on top of the reduced tillage, compost, and mulching treatment showed no further effect, with 7.17 (±0.79) kg N2O-N ha-1. Mulching contributed to the emission reduction through the combined effects of dead and living mulch: dead mulch effectively damped soil temperatures, reducing heat stress during the warm, dry summer of 2022, which likely enhanced nitrogen (N) uptake by the potatoes, in combination with nitrogen immobilization due to its high C:N ratio, thereby reducing a high post-harvest N2O emission peak observed across all treatments. In the winter wheat-pea mixture, two consecutive emission peaks occurred post-harvest; these were mitigated by the enhanced growth of the undersown living mulch, likely resulting in N uptake during this critical period. Our findings indicate that mulching can overcompensate the tendency of long-term compost applications to increase N2O emissions when both management measures are combined.
How to cite: Aumer, W., Görres, C.-M., Bilibio, C., Niether, W., Leisch, S., Junge, S. M., Weber, T. K. D., Gattinger, A., Peth, S., Finckh, M. R., and Kammann, C.: Effects of regenerative agricultural measures on soil nitrous oxide emissions in organic farming, EGU General Assembly 2026, Vienna, Austria, 3–8 May 2026, EGU26-10013, https://doi.org/10.5194/egusphere-egu26-10013, 2026.
Agricultural soils are the largest anthropogenic source of nitrous oxide (N₂O), a potent greenhouse gas and an ozone-depleting substance. We investigated the seasonal and diurnal variability of N₂O fluxes and their controlling factors in an agricultural ecosystem at the SMEAR-Agri Viikki site (Helsinki, Finland) over three years. The field was cultivated with timothy (Phleum pratense) in 2022 and was renewed in spring 2023 with barley (Hordeum vulgare) undersown with red clover (Trifolium pratense) and grasses; in 2024 the site was managed for silage production. N₂O emissions in 2022 showed no consistent seasonal pattern but a high early-summer emission peak, whereas 2023 and 2024 were characterised by multiple emission events with smaller magnitudes. Minimum fluxes occurred in autumn 2022 (0.003 µg m⁻² s⁻¹), winter 2023 (0.008 µg m⁻² s⁻¹) and summer 2024 (0.006 µg m⁻² s⁻¹). The highest fluxes were observed in 2022 summer (0.089 µg m⁻² s⁻¹) and spring (0.088 µg m⁻² s⁻¹), while peak emissions in 2023 (0.028 µg m⁻² s⁻¹) and 2024 (0.032 µg m⁻² s⁻¹) occurred during autumn. Our results highlight strong interannual variability in both the timing and magnitude of N₂O emissions, likely linked to changes in crop N utilization and management, soil conditions and meteorological drivers. Seasonal variations in N₂O emissions during spring, summer and autumn were primarily driven by soil and meteorological factors, including air and soil temperature, soil moisture, water-filled pore space, electrical conductivity and redox potential. During winter, however, N₂O fluxes showed little association with these variables, suggesting a shift in controlling processes under cold conditions. Overall, the findings reveal substantial seasonal and interannual complexity in N₂O dynamics and underscore the importance of integrating soil conditions, management practices and seasonal context when assessing and mitigating N₂O emissions from managed agricultural systems.
Keywords: Nitrous oxide flux, greenhouse gas, seasonal variability, agricultural ecosystems, soil moisture, temperature.
How to cite: Rao, K., koskinen, M., Lohila, A., Buzacott, A., Korkiakoski, M., Vekuri, H., Polvinen, T., and Pihlatie, M.: Seasonal and Temporal Variability and drivers of Nitrous Oxide Emissions from Northern Agriculture Soil, EGU General Assembly 2026, Vienna, Austria, 3–8 May 2026, EGU26-11923, https://doi.org/10.5194/egusphere-egu26-11923, 2026.
Fluxes of carbon dioxide (CO2), methane (CH4) and nitrous oxide (N2O) from croplands, as well as evapotranspiration (ET) are regulated by complex interactions among abiotic and biotic factors, which are strongly modified by environmental conditions, crop growth and management practices. This study investigated how CO2, CH4 and N2O fluxes and ET developed during the cultivation of spring wheat and the subsequent cover crop (oil radish) in an organic farming field at the Wiesengut experimental farm of the University of Bonn, located in Rhein-Sieg district of Germany. Since March 2025, we continuously monitor net ecosystem CO₂ exchange and evapotranspiration using the eddy covariance technique. In parallel, we conducted weekly measurements of CO2, CH4 (starting in July 2025) and N2O (since May 2025) fluxes using static chambers and laser-based CO2/CH4/H2O and N2O/H2O analyzers and monitored soil mineral nitrogen.
Eddy covariance data showed sustained CO2 uptake during the spring wheat growing season with mean NEE of -8.49 ± 0.62 µmol m-2 s-1during the mid-season (32-102 days after sowing). The harvest, incorporation of crop residues and manure application resulted in slightly positive NEE fluxes, which then fluctuated close to zero during the oil radish period in autumn and winter. ET fluxes were also associated with crop development, with largest fluxes measured in mid-June 2025. Carbon dioxide fluxes measured with the chambers in the ripening stage of spring wheat, July 2025, indicated moderate soil and plant respiration, while after harvest and soil management operations CO2 efflux increased and became more variable, reaching peak values of up to 12.34 ± 2.3 µmol m-2 s-1. Methane fluxes were predominantly negative throughout the study, indicating that the soil acted mainly as a methane sink. The strongest uptake occurred in the limited pre-harvest measurements, reaching -61.76 ± 7.7 µg CH4 m-2 h-1. After harvest and soil disturbance, CH4 uptake weakened, with fluxes approaching zero during late autumn. Nitrous oxide fluxes exhibited clear seasonal dynamics showed generally low emissions during most of the spring wheat growing season, fluctuating around zero. In contrast, strong and short-lived emission peaks occurred after harvest and subsequent management operations, with maximum fluxes reaching 66.47± 14.14 µg N2O-N m-2 h-1. During the oil radish period, fluxes rapidly declined and remained mostly low, with only occasional episodic increases.
Our results demonstrate that greenhouse-gas and water dynamics in organic cropping systems vary strongly across crop and cover-crop phases and are tightly coupled to post-harvest management. These findings improve process-based understanding of GHG fluxes in organic rotations, including cover crops, and support the development of mitigation strategies for climate-smart agriculture.
How to cite: Jahanbakhshi, F., Iddris, N. A.-A., Bonazza, M., Kraus, S., Tyystjärvi, V., and Meijide, A.: Seasonal dynamics of CO2, CH4 and N2O fluxes and evapotranspiration in an organically managed cropping system, EGU General Assembly 2026, Vienna, Austria, 3–8 May 2026, EGU26-18869, https://doi.org/10.5194/egusphere-egu26-18869, 2026.
Soil salinity is an escalating global challenge that reduces crop productivity and exacerbates reactive nitrogen (Nr) losses, threatening food security and environmental health. However, the dual impacts of salinity on crop yields and nitrogen cycling remain under-quantified at the global scale. This study aims to quantify how salinity alters nitrogen dynamics and yield outcomes in croplands and to assess the effectiveness of integrated mitigation strategies designed to reverse these adverse trends. We focus on identifying practical solutions that deliver co-benefits for agricultural output and environmental sustainability in saline croplands. For this, we integrate the IMAGE and CHANS models to construct the nitrogen budget for saline croplands worldwide. A pairwise comparison framework was employed to quantify changes in nitrogen flows across saline and non-saline conditions. Additionally, a global database of field-based mitigation strategies and simulated combined interventions to evaluate their effectiveness. Afterwards, cost-benefit analysis was conducted to evaluate the societal benefits of implementing mitigation measures at scale. Our results show that soil salinity increases nitrogen inputs by 13%, exceeding 1 million tonnes per year, while reducing nitrogen harvest by 7% and amplifying Nr losses by 61%. To assess mitigation potential, we compile and evaluate ten categories of salinity management measures, which collectively reduce Nr losses by 58%, equivalent to 1.9 million tonnes annually, while enhancing yield and generating net global benefits of approximately US$12.6 billion. Regional analyses highlight Asia (e.g., China, Pakistan, Indonesia) and the Middle East (e.g., Iran, Egypt, Saudi Arabia) as hotspots for saline croplands mitigation. The study provides an evidence-based framework for integrating nitrogen budgeting with mitigation policy and highlights the importance of prioritizing salinity mitigation policies and enhancing sustainable agriculture management under increasing environmental stressors.
How to cite: Wen, W. and Gu, B.: Managing saline soil to boost crop yield and halve nitrogen losses, EGU General Assembly 2026, Vienna, Austria, 3–8 May 2026, EGU26-2919, https://doi.org/10.5194/egusphere-egu26-2919, 2026.
Nitrogen losses following fertilizer application not only cause nutrient loss to the crops, but also have negative environmental impacts, including ammonia (NH3) and greenhouse gas emissions (GHG) (e.g., nitrous oxide, N2O). Numerous studies have been carried out to investigate the efficiency of fertilizer use, aiming to increase crop yield and reduce environmental impacts including GHG and other gaseous emissions. There are different measurement approaches of quantifying gaseous nitrogen (N) losses, and static chamber methods are the most commonly used approach for directly measuring emissions from soils. However, chambers interfere with the soil environment, the small measurement footprint of chambers is unable to represent the large source area and are poorly suited for long-term measurements. Here, we demonstrated the use of slant-path Fourier transform infrared spectroscopic (FTIR) technique to continually measure NH3 and N2O emission rates from wheat crops for 4 weeks following fertilizer application. The study was conducted in a wheat farm in Victoria, Australia in winter season in August 2025. Urea with (treatment) and without (control) a urease inhibitor was applied to the wheat crop at a rate of 98 kg N/ha. Line-averaged concentrations of NH3 and N2O from each plot were continually measured with vertically separated measurement paths using an OP-FTIR and wind information was recorded by a 3-D sonic anemometer. Fifteen-min average NH3 and N2O emission rates were calculated based on the measured concentrations and wind information. The results showed that NH3 emission rates increased immediately after urea was applied, with greater increase than the untreated urea. Ammonia emission rates from the urease inhibitor treatment increased in the third week following fertilization, while ammonia emission rates from the control site started decreasing. Preliminary results show that the accumulative NH3 and N2O emissions from the urea plot were ~3 and 1.6 times higher than that from the urease inhibitor treated plot, respectively. The higher NH3 and N2O emissions following non-treatment urea application highlighted the benefits of a urease inhibitor for reducing N loss under high ambient temperature and lack of rainfall for 2 weeks following fertilization. Further benefits could be achieved in N use efficiency by reducing the N application rate when using the urease inhibitor.
How to cite: Bai, M., Pandy, A., Chen, D., and Suter, H.: The use of slant-path FTIR techniques to measure gaseous N loss in Australian dryland wheat following urea/urease inhibitors fertilizers application, EGU General Assembly 2026, Vienna, Austria, 3–8 May 2026, EGU26-15845, https://doi.org/10.5194/egusphere-egu26-15845, 2026.
Synthetic pesticides applied in agricultural fields to control pests can volatilize into the atmosphere in either gas or particle phase (Rajmohan et al., 2020). Understanding the biosphere–atmosphere exchange of these compounds is crucial, as this exchange influences various atmospheric chemical processes that ultimately determine the environmental fate of pesticides. However, data quantifying these processes remain limited (Hörtnagl et al., 2010).
This work aims to test the eddy covariance flux system developed by combining a High-Resolution Time of Flight Iodide Chemical Ionization Mass Spectrometer (HR-TOF-I-CIMS) which measures a wide range of compounds including pesticides in the atmosphere at 10 Hz, with a Sonic Anemometer which gives high frequency vertical wind speed. These two observations can be combined to obtain the biosphere to atmosphere exchange of pesticides.
Here we are going to present the results from the campaign which was conducted from 20th march to 14th April 2025, at an arable farm located in Rothamsted Research, Okehampton, Devon (50°46'26.4"N 3°54'11.2"W). The site had minimal local obstructions, essential to capture well developed turbulent eddies.
The measurements were done at a height of 3.6 m above ground and the I-CIMS was kept in a temperature-controlled trailer with a heated inlet mounted at the top of the trailer connecting the two instruments.
Initial results indicate successful capture of atmospheric turbulence, with a footprint extent of approximately 350 m in both directions at the given measurement height. Flux footprint analysis (Figure), performed using a simple two-dimensional parameterization model (Kljun et al., 2015), revealed major contributions from the SE and NW directions.
Additionally, preliminary results with targeted analysis via CIMS for fluxes of specific compounds will be presented, validating system performance, followed by spectra and cospectra analysis that reveals the contributions across different frequency scales.
How to cite: Arora, U., Coe, H., Bannan, T., Allan, J., Cardenas, L., Flynn, M., Wu, R., Matthews, E., and Johnston, S.: An Eddy Covariance System to Quantify Fluxes of Pesticides in an Agricultural Environment, EGU General Assembly 2026, Vienna, Austria, 3–8 May 2026, EGU26-7426, https://doi.org/10.5194/egusphere-egu26-7426, 2026.
In the Netherlands, ammonia (NH₃) emissions from livestock housing have become a major environmental concern, largely due to high density of livestock farms in certain areas of the country. After emission, NH3 settles on the ground, lowering the soil pH, leading to increased acidity and creating harmful conditions for plants. To protect biodiversity, it is essential to reduce nitrogen emissions. This study investigates the spatial variation in NH3 deposition from livestock farming in 2020 within one of the hotspot regions in the Netherlands (Foodvalley region), using a high resolution dispersion model (STACKS-D). The spatial mean NH3 deposition from livestock emissions in Foodvalley was found to be 11.14 kg/hectare/year. Levels above critical deposition load (17 kg/ha/year) were mainly observed in central areas and some nature reserves. To eliminate these exceedances, we tested various livestock emission reduction scenarios. All scenarios explored were able to reduce deposition in nitrogen-sensitive nature environments significantly. Scenarios targeting stable removal in buffer zones around nature areas, as well as those focused on veal calves, dairy cattle, and laying hens sectors, were highly effective in reducing deposition with potentially smaller influence on existing livestock sectors. The annual average deposition map generated by STACKS-D, demonstrated consistent spatial characteristic with 2020 large-scale deposition map, which serves as a reference for assessing pollution distribution and policy making in the Netherlands. Furthermore, a strong (~0.8) and statistically significant correlation between modelled and measured annual mean NH₃ air concentrations as observed for the period 2022-2023 indicates the model captures key spatial features.
How to cite: Govande, A., Martins Figueiredo, D., van Wijk, D., Heederik, D., Raben, C., Lô, S., Erbrink, H., Dohmen, W., and Falakdin, P.: Assessing Ammonia Deposition Patterns and Emission Reduction Scenarios in a Livestock-Dense Region of the Netherlands Using a High Resolution Dispersion Model., EGU General Assembly 2026, Vienna, Austria, 3–8 May 2026, EGU26-1306, https://doi.org/10.5194/egusphere-egu26-1306, 2026.
Posters on site: Mon, 4 May, 10:45–12:30 | Hall X1
Anthropogenic greenhouse gas emissions continue to drive global climate change, highlighting the importance of terrestrial ecosystems in regulating atmospheric carbon. While vegetation acts as a major carbon sink through photosynthetic uptake and biomass accumulation, carbon sequestration research has predominantly focused on forest ecosystems. In contrast, agricultural systems—especially perennial crops—remain comparatively underrepresented despite their extensive land coverage and long-term management.
Tea plantations (Camellia sinensis) are perennial agroecosystems composed of long-lived woody shrubs with repeated harvest cycles and sustained biomass, suggesting a potentially significant but poorly constrained role in terrestrial carbon cycling. In Taiwan, tea is a major commercial crop occupying extensive agricultural land, yet quantitative assessments of plant–soil carbon exchange processes in tea systems remain limited. To better understand carbon exchange processes in tea plantations, this study applies a dual-approach integrating plant- and soil-level greenhouse gas measurements in a managed tea garden in Taiwan.
Field measurements were conducted from January to April 2026. Branch-level photosynthesis and respiration were monitored using branch cuvettes, and gas exchange rates were extrapolated to the plant level using allometric relationships. Concurrently, soil carbon dioxide (CO2) fluxes were measured using static chamber techniques to characterize soil–atmosphere carbon exchange, with fluxes further extrapolated to the garden scale. Measurements were repeated monthly under fair-weather conditions and supported by laboratory gas chromatography analysis. Ancillary environmental variables and management activities were recorded to support flux interpretation.
Overall, this study provides an integrated, field-based assessment of carbon exchange dynamics in a managed tea plantation by explicitly linking plant- and soil-level gas fluxes with seasonal progression and agricultural practices. By aligning greenhouse gas measurements with farming activities, the results offer insight into how management and phenological stages jointly regulate carbon exchange in perennial agroecosystems. The findings contribute to reducing current uncertainties surrounding the role of tea plantations in terrestrial carbon cycling and provide a scientific basis for future evaluations of carbon management and climate mitigation potential in perennial agricultural systems.
How to cite: Huang, Y.-N. and Liao, K.-W.: Integrating Branch- and Soil-Level Flux Measurements to Investigate Carbon Exchange Dynamics in Tea Plantations, EGU General Assembly 2026, Vienna, Austria, 3–8 May 2026, EGU26-4908, https://doi.org/10.5194/egusphere-egu26-4908, 2026.
The management of cropping systems can substantially impact the amount of CO2 emitted, such as during fertilisation, tillage and bare soil conditions. Smart and optimised management practices can promote sustainable farming allowing for maximum yields and fertile soils at the same time. This study aims to investigate the impact of management interventions on CO2 and energy fluxes at a cropland site in central Germany.
In our study, continuous CO2, water, and energy fluxes have been measured at the Reinshof (DE-Rns; 51°29'24.0"N, 9°55'55.2"E) agricultural FLUXNET site near Göttingen, Germany, since 2021. The field is conventionally managed, with a typical crop rotation (winter barley, sugar beet, winter wheat), deep tillage and received both organic and mineral fertilisation. Measurements are performed at a 6.5 m tall flux tower equipped with an eddy covariance setup (uSONIC3-omni Cage MP, METEK; LI7200, LI-COR) for CO2, water, and energy fluxes, as well as ancillary meteorological instruments.
The results indicate that gross primary productivity and ecosystem respiration were the highest during the cultivation of sugar beet compared to all cereals grown in the other years (wheat and barley), with values that were 20% and 6% higher, respectively. This resulted in a 50% higher net ecosystem productivity. Evapotranspiration was 21% higher than for the other crops. The high productivity of sugar beet in terms of carbon and ET fluxes can be explained by (i) its high natural efficiency in sequestering carbon, (ii) the extended growing season and (iii) the higher leaf area index compared to cereals (wheat or barley). Despite the higher fluxes, the annual water use efficiency of sugar beet was similar to that of wheat and barley. Furthermore, we demonstrate that bare soil conditions lead to carbon losses, which could be mitigated through the extended cultivation of cover crops.
In conclusion, both management and crop rotation had the greatest impact on the variability of annual carbon and evapotranspiration budgets, suggesting that management plays a relevant role in carbon and water fluxes in croplands and can be used to increase the carbon uptake.
How to cite: Markwitz, C., Emad, A., Englert, P., Meijide, A., Münter, C., Tunsch, E., and Knohl, A.: CO2, water and energy fluxes over a cropland in central Germany, EGU General Assembly 2026, Vienna, Austria, 3–8 May 2026, EGU26-7237, https://doi.org/10.5194/egusphere-egu26-7237, 2026.
Agriculture is under increasing pressure to reduce greenhouse gas emissions as part of global efforts to mitigate climate change and ensure sustainable food production. Among these emissions, nitrous oxide (N₂O) is a particularly potent greenhouse gas, largely originating from agricultural soils, which makes effective mitigation strategies crucial. Winter rye has been identified as a potential biological nitrification inhibitor due to its release of the compound 6-methoxy-2-benzoxazolinone (MBOA) by the roots. This compound suppresses nitrifying bacteria, thereby reducing the conversion of ammonia to nitrate in soil systems and ultimately lowering N₂O emissions. Unlike chemical nitrification inhibitors, whose environmental side effects remain insufficiently understood, biological nitrification inhibitors occur naturally and offer a promising, sustainable alternative for reducing emissions in agricultural systems. We tested the nitrification inhibiting effect of MBOA in Danish fields under common Danish farming practices. The aim was to determine the degree of N₂O reduction by winter rye, compared to cereals without a biological nitrification function. If successful, winter rye could be a low-emission substitute for similar crops, providing farmers with a practical tool to reduce greenhouse gas emissions without compromising crop management, aligning with EU climate targets and sustainable agriculture goals. Three field trials were conducted in West Jutland, Denmark. Winter wheat was selected as a control species with no genes producing MBOA. To account for different N-demands in rye and wheat, both species received three different N-treatments: 0, 130 and 190 kg N ha-1, respectively. We measured N₂O emissions 20 times during the growing season using the static chamber method along with soil N contents and -moisture. As expected, N₂O emissions increased with increasing N amounts applied in both species. Although variability was observed among trials, results indicated an overall trend toward lower N₂O emissions from winter rye compared to winter wheat under the high N application (p < 0.07). These findings suggest that winter rye can act as a biological nitrification inhibitor under field conditions, contributing to reduced N₂O emissions and supporting agricultural practices with lower carbon footprints. Further trials will assess the consistency of these effects across varying weather conditions, aiming to strengthen recommendations for large-scale implementation. If confirmed, this strategy could offer a scalable, low-cost approach to reducing agricultural greenhouse gas emissions without major changes to current farming systems.
How to cite: Baggesen, N., Eller, F., Mortensen, L., Lykke, E., and Nielsen, C.: Field evaluation of winter rye as a biological nitrification inhibitor to reduce nitrous oxide emissions, EGU General Assembly 2026, Vienna, Austria, 3–8 May 2026, EGU26-7295, https://doi.org/10.5194/egusphere-egu26-7295, 2026.
Alternate Wetting and Drying (AWD) is widely advocated as a strategy to reduce methane (CH4) emissions from rice paddies by decreasing the duration of flooding. However, AWD implementation can differ substantially across climatic regions and agricultural systems. It is not yet established whether water management affects only the magnitude of CH4 emissions or also modifies the dominant environmental controls governing sub-daily flux variability, particularly the interaction between water status, temperature, and other micrometeorological variables.
The current research evaluates whether different water-management regimes yield distinct emission-control outcomes by comparing the nonlinear hierarchies of ecological drivers influencing half-hourly CH4 fluxes across three rice systems: continuously flooded (CF) and two distinct AWD practices.
Half-hourly CH4 fluxes and associated drivers were analysed from three rice systems: the Philippines, Japan, and South Korea. Fluxes were standardised and paired with engineered hydrologic and micrometeorological predictors, including water depth, depth-change rates, hydroperiod integral (hydrologic memory), psychrometric variables, diurnal harmonics, and interaction terms. Multivariate generalised additive models (GAMs) were constructed using normalised predictors and assessed with 80/20 train–validation splits. The importance of each driver was determined using permutation ΔRMSE and drop-one diagnostics.
Three distinct emission-control regimes were identified. In Japan (characterised by continuous flooding), moderate mean emissions (5.70 mg CH4 m−2 h−1) were regulated mainly by water–temperature interactions, suggesting thermal buffering by standing water. South Korea (AWD with regular wet–dry cycling) exhibited the highest emissions (16.71 mg CH4 m−2 h−1) and a transition toward direct atmospheric forcing, with air temperature as the dominant predictor and minimal influence from water–temperature interactions. The Philippines (aerobic-dominated AWD) demonstrated the lowest emissions (1.92 mg CH4 m−2 h−1), with hydrologic memory and dryness as the primary modulators.
Water management influences both the magnitude of CH4 emissions and the dominant controlling mechanisms: thermal buffering prevails under continuous flooding, atmospheric forcing under frequent wet–dry cycling, and hydrologic memory under aerobic-dominated AWD. Our analysis shows that AWD encompasses fundamentally different emission regimes. The climate benefits of AWD depend on drainage depth, cycle frequency, and the persistence of aerobic conditions. An AWD typology that distinguishes practices by their dominant control mechanisms is suggested to strengthen emission inventories, MRV frameworks, and management guidance.
How to cite: Zerrudo, J., Bataille, L., Hutjes, R., Kruijt, B., Sander, B. O., Centeno, C. A., and Wassmann, R.: Water Management Alters Emission Behaviour: Comparative Analysis of Methane Flux Drivers in Three Rice Systems Using Generalised Additive Models , EGU General Assembly 2026, Vienna, Austria, 3–8 May 2026, EGU26-16779, https://doi.org/10.5194/egusphere-egu26-16779, 2026.
Monitoring as many trace and greenhouse gas fluxes as possible is essential for understanding the interactions between the atmosphere, vegetation, and soil, the key components of agricultural ecosystems. In these complex environments, capturing a complete flux budget requires the simultaneous measurement of a wide range of inert and reactive trace gases, as well as greenhouse gases.
Until recently, gas flux monitoring was typically limited to just a few gases per instrument, making the process both complex and costly while offering only a partial view of emitted gas composition. MIRO Analytical has addressed this limitation by developing a novel multi-compound gas analyzer capable of simultaneously measuring up to 10 air pollutants (CO, NO, NO2, O3, SO2 and NH3), greenhouse gases (CO2, N2O, H2O, CH4 and C2H6) and other atmospheric trace gases such as OCS, HONO and CH2O at ppb or even ppt levels.
One single analyzer can be used to conduct eddy covariance (EC) measurements, which require a high temporal resolution. With a cell turnover time below 0.1 seconds, our compact instrument combining multiple mid-infrared quantum cascade lasers delivers true 10 Hz sampling with exceptional precision. The very same analyzer can also be used to measure fluxes captured by (soil-)incubation chambers. It can be installed on mobile platforms and is field deployable.
In this contribution, we showcase the capabilities of our all-in-one flux monitor through application examples that demonstrate unique combinations of up to 10 trace and greenhouse gases measured with the EC or flux gradient technique, as well as on-field and lab chamber measurements.
How to cite: Bruckhuisen, J., Smith, E., and Espic, C.: Simultaneous flux monitoring of 10 trace and greenhouse gases with a single instrument ideal for complex agricultural ecosystems, EGU General Assembly 2026, Vienna, Austria, 3–8 May 2026, EGU26-17123, https://doi.org/10.5194/egusphere-egu26-17123, 2026.
Bog peatlands in northwestern Germany release high amounts of greenhouse gas (GHG) emissions. Most of these bogs were drained, resulting in intensively used grasslands primarily for dairy production. While dairy production is economically highly important in the region drained bogs with intensive grassland use show high CO2 emissions. To reduce GHG-emissions from intensively managed grasslands on bogs used for dairy production, the GreenMoor project investigates the effects of different water management approaches, such as such as subsurface irrigation and ditch blocking, as well as different usage practices including different fertilization intensities and pasture or cutting regimes. With a unique and expansive setup, we investigate the full GHG-balance of these different variants using manual chambers. We aim to present preliminary results from the first project phase including preliminary GHG-balances and an outlook on the potential success of different management approaches to reduce GHG-balances from drained intensively used bogs.
How to cite: Taube, R., Köhn, D., Gerken, H., Krause, A., and Jurasinski, G.: Impact of Water Management and Land Use Practices on Greenhouse Gas Emissions from an Intensively Farmed Bog Grassland in Northwest Germany, EGU General Assembly 2026, Vienna, Austria, 3–8 May 2026, EGU26-23185, https://doi.org/10.5194/egusphere-egu26-23185, 2026.
Bioenergy derived from biofuels can help slow the rise of atmospheric CO2 by displacing fossil fuel consumption. Yet, cultivating bioenergy feedstocks requires substantial land area. In the United States, the recent growth of maize-based ethanol has entailed environmental trade-offs, motivating interest in alternative feedstocks. Many of these candidates have been chosen partly for characteristics linked to ecosystem services and may therefore deliver environmental gains beyond simple fossil-fuel substitution. We proposed that bioenergy cropping systems could also generate direct climatic cooling by altering carbon exchange and radiative energy fluxes (e.g., via surface albedo). To evaluate this proposition, we quantified the potential cooling influence of five current or prospective bioenergy feedstocks using multi-year eddy-covariance tower datasets. Perennial systems functioned as carbon sinks, with annual mean net ecosystem carbon balance (NECB) of −2.7 ± 2.1 Mg C ha−1 for miscanthus, −0.8 ± 1.1 Mg C ha−1 for switchgrass, and −1.4 ± 0.7 Mg C ha−1 for prairie. By contrast, annual rotations were generally carbon sources, with annual mean NECB of 2.6 ± 2.4 Mg C ha−1 for maize–soy and 3.2 ± 2.1 Mg C ha−1 for sorghum–soy. Using maize–soy as the reference system, conversion to the alternative feedstocks increased albedo and produced additional cooling. This radiative effect was largest for miscanthus (−3.5 ± 2.0 W m−2) and smallest for sorghum (−1.4 ± 1.4 W m−2). When carbon- and albedo-driven impacts were compared using carbon-equivalent metrics, carbon exchange emerged as the dominant ecosystem effect, reinforcing the importance of perennial species as effective carbon sinks. Overall, these results demonstrate that feedstock selection strongly shapes ecosystem processes and should be considered an integral component of bioenergy land-conversion strategies.
How to cite: Bernacchi, C., Blakely, B., Moore, C., Pederson, T., Gibson, C., Benson, M., and Dracup, E.: Climate Forcing of Bioenergy Feedstocks: Insights FromCarbon and Energy Flux Measurements, EGU General Assembly 2026, Vienna, Austria, 3–8 May 2026, EGU26-19694, https://doi.org/10.5194/egusphere-egu26-19694, 2026.
Agricultural systems are a major source of nitrous oxide (N2O) emissions. Nitrous oxide is a potent greenhouse gas (GHG) emitted from managed grasslands and croplands, primarily as a result of nitrogen fertilization. Reducing nitrogen inputs alone can mitigate N2O emissions, but this may compromise crop productivity. Alternative mitigation strategies are therefore required to sustain food production while reducing GHG emissions. Currently one of the most promising strategies to do that is the use of nitrification inhibitors (NIs).
Nitrification inhibitors act by suppressing the activity of nitrifying microorganisms for a period, thereby slowing the conversion of ammonium to nitrate. This reduces N2O emissions from ammonia oxidation and the availability of nitrate for subsequent denitrification and associated N2O emission. Fertilizers amended with NIs may improve plant nitrogen uptake and reduce nitrogen losses. In a second-order meta-analysis, Grados et al (2022) found an average reduction of 44 % in N2O emissions when NIs are used as fertilizer amendment. However, effects may vary among studies, potentially due to variable soil and climate conditions, as well as different management (time, rate and method of application).
To obtain a more robust estimate of the effectiveness and key drivers of nitrification inhibitors under temperate conditions, we conducted a meta-analysis of studies reporting cumulative N2O emissions from NI-amended fertilization in northern European climate. Literature was identified using Web of Science (all databases) by combining search terms related to nitrous oxide and nitrification inhibitors. The initial search yielded 9,387 references, which were filtered using exclusion terms implemented in R, followed by manual screening of approximately 100 abstracts. In total, 43 studies met the inclusion criteria and were included in the analysis.
Preliminary results based on studies from Denmark only (n= 10) show a statistically significant average decrease of 40% in N2O emissions, when NIs are used as fertilizer amendment. However, factors such as sand content and concentration of nitrogen applied significantly affect the inhibitors mitigation efficiency.
Reference: Grados et al 2022 Environ. Res. Lett. 17 114024, DOI 10.1088/1748-9326/ac9b50
How to cite: Hindborg Mortensen, L., Tariq, A., S. Baggesen, N., Skov Nielsen, C., Høegholm Lykke, E., Bruun, S., O. Petersen, S., and Eller, F.: Effectiveness and key drivers of nitrification inhibitors in mitigating N2O Emissions in a cool temperate climate: A Meta-analysis, EGU General Assembly 2026, Vienna, Austria, 3–8 May 2026, EGU26-12032, https://doi.org/10.5194/egusphere-egu26-12032, 2026.
The case for mitigating greenhouse gas emissions from rice production systems is well recognised. Among different strategies, alternate wetting and drying (AWD) has emerged as a low-tech, water-saving approach with strong emission mitigation potential. Intermittent drying of rice fields creates an aerobic environment that suppress methane production. We present a multi-season, landscape-scale assessment of AWD in intensive rice cultivation systems of Telangana state in Southern India. Using a robust experimental design, we quantified irrigation water use, crop productivity, and methane emissions, measuring methane fluxes with static closed chambers. Across seasons, AWD consistently lowered methane emissions relative to conventional continuously flooded systems while maintaining grain and biomass yield. Irrigation demand was reduced under AWD, with water savings ranging from ~14% to ~37%. When conservatively scaled, emission reductions correspond to mitigation potentials of 2.5-3.5 Mt CO2-eq ha-1 season-1. These observations enabled the calibration and validation of process-based biogeochemical crop models, which were subsequently extrapolated to the project region using a remote-sensing-based framework. Overall, this work highlights AWD as a scalable lever for reducing emissions, conserving water and improving regional inventories, while strengthening voluntary carbon market accounting and sustainability assessments in rice production systems.
How to cite: Ajmera, I., Sirimalle, M., Konkathi, P., Bhatia, A., Li, T., and Torbick, N.: QUAntifying ricE gReenhouse gas Emissions (QUAERE): Mitigation Potential of Sustainable Irrigation Practice in India, EGU General Assembly 2026, Vienna, Austria, 3–8 May 2026, EGU26-3380, https://doi.org/10.5194/egusphere-egu26-3380, 2026.
Thailand is a major national source of methane (CH₄) from irrigated rice, yet its national greenhouse gas inventory applies fixed IPCC Tier-2 seasonal emission factors. Tier-2 follows the IPCC scaling-factor framework but replaces default parameters with country- or region-specific values derived from local data. For irrigated rice in Thailand’s Central/Southern region, the inventory applies fixed seasonal factors of 143 and 71.8 kg CH₄ ha⁻¹ season⁻¹ for the main and second crops, respectively, which may not reflect heterogeneity in farm management and soils. Using survey and soil data from irrigated farms in Central Thailand, we evaluated the sensitivity of estimated seasonal CH₄ emissions to water regime, residue management, and soil organic carbon (SOC) by comparing Thailand’s Tier-2 reference with four estimation approaches: IPCC, (2019) and the empirical/statistical models of Yan et al. (2005), Wang et al. (2018), and Nikolaisen et al. (2023). For the analysed farms, multiple drainage water management was common (54.0% in the main crop; 52.8% in the second crop), while straw incorporation occurred in 38.7% of farms before the main crop and 27.8% before the second crop. Sensitivity was quantified using a structured scenario framework. Scenario 0 was a counterfactual baseline (continuous flooding, no residue inputs). Water effects were isolated as Scenario A−0, residue effects as Scenario B−0, and combined effects under current practices as Scenario C−0. In the main season, drainage effects were negative for 149 of the 150 farms. Residue effects produced large upper-quartile increases (Q3 = 295–390 kg CH₄ ha⁻¹ season⁻¹ across models). Under current practices, the median net effect remained negative, but high-emitting cases persisted. Across seasons, empirical/statistical models produced higher medians and wider farm-to-farm distributions than the Thai Tier-2 reference factors. SOC further structured variability under current practices, with farms >2% SOC disproportionately represented among the highest estimated emitters. These results indicate that fixed seasonal emission factors can mask management and soil heterogeneity, and that more detailed activity data on drainage techniques, residue incorporation, and soil carbon status are necessary to improve Thai rice methane inventories.
Reference
IPCC. (2019). 2019 Refinement to the 2006 IPCC Guidelines for National Greenhouse Gas Inventories: Volume 4: Agriculture, Forestry and Other Land Use (E. Calvo Buendia, K. Tanabe, A. Kranjc, J. Baasansuren, M. Fukuda, S. Ngarize, A. Osako, Y. Pyrozhenko, P. Shermanau, & S. Federici, Eds.). IPCC. https://www.ipcc-nggip.iges.or.jp/public/2019rf/vol4.html
Nikolaisen, M., Cornulier, T., Hillier, J., Smith, P., Albanito, F., & Nayak, D. (2023). Methane emissions from rice paddies globally: A quantitative statistical review of controlling variables and modelling of emission factors. Journal of Cleaner Production, 409, 137245. https://doi.org/10.1016/j.jclepro.2023.137245
Wang, J., Akiyama, H., Yagi, K., & Yan, X. (2018). Controlling variables and emission factors of methane from global rice fields. Atmospheric Chemistry and Physics, 18(14), 10419–10431. https://doi.org/10.5194/acp-18-10419-2018
Yan, X., Yagi, K., Akiyama, H., & Akimoto, H. (2005). Statistical analysis of the major variables controlling methane emission from rice fields. Global Change Biology, 11(7), 1131–1141. https://doi.org/10.1111/j.1365-2486.2005.00976.x
How to cite: Sudto, T., Mcbey, D., Smith, P., and Vetter, S.: Sensitivity of methane estimates for irrigated rice in Thailand: A comparison of Tier-2 factors and empirical models regarding water and residue management, EGU General Assembly 2026, Vienna, Austria, 3–8 May 2026, EGU26-5801, https://doi.org/10.5194/egusphere-egu26-5801, 2026.
Nitrous oxide (N₂O) is a major agricultural greenhouse gas and a reactive nitrogen species that drives climate forcing and environmental degradation. Its low ambient concentration and episodic bursts following fertilization or rainfall make detection difficult, requiring instruments capable of high sensitivity and temporal resolution to capture rapid flux dynamics.
This work introduces an open-path N2O laser analyzer (Model: HT8500, HealthyPhoton Co., Ltd.) designed for future applications in N₂O monitoring and EC flux measurements. The HT8500 utilizes an quantum cascade laser (QCL) to probe the mid-infrared transition of N2O at 4.54 μm. Laboratory experiments revealed that the HT8500 has a noise level of 0.3 ppbv at a 10-Hz sampling rate with a typical power consumption < 25 Watts.
A long-term field experiment based on the HT8500 over a bare agricultural field in Shandong, China was conducted to test “zero-flux” measurements and computations under different meteorological conditions. The resulting minimum detectable flux (~26.549 μg N m⁻² h⁻¹) indicates performance comparable to commercially available chamber-based N2O flux measurement scenarios.
In the experiments conducted in Northeast China, the fertilization period was concluded. As temperatures decrease, the diurnal variation in N2O fluxes dropped significantly, indicating the influence of temperature on eddies when emission sources remain stable. Continued evaluation will clarify how climate conditions and agricultural practices shape flux variability.
Such analyzer was also deployed on a EV based plume sensing platform (Farizon SV), along with open-path NH3, CH4, H2O laser analyzers (model HT8700, HT8600P, respectively). We conducted mobile monitoring campaigns at wastewater treatment plants in Jinan, Beijing and Shanghai, all employed the Anaerobic–Anoxic–Oxic (AAO) process. Synchronized plume signals of GHGs above background were detected, with CH₄:N₂O concentration ratios ranging from 4.06:1 to 5.93:1, indicative of anaerobic contributions and process-dependent emission signatures.
How to cite: Jiang, R., Wang, K., Su, C., Lin, T.-J., Shen, W., Wilson, D., and Wang, Y.: An open-path nitrous oxide laser analyzer for eddy covariance flux and mobile monitoring applications, EGU General Assembly 2026, Vienna, Austria, 3–8 May 2026, EGU26-16420, https://doi.org/10.5194/egusphere-egu26-16420, 2026.
