Use of open-path FTIR and inverse dispersion technique to quantify gaseous nitrogen loss from an intensive vegetable production site

SUMMARYAmmonia volatilization and denitrification were measured in a ryegrass field in Denmark after direct injection and application with trail hoses of an untreated cattle slurry and an anaerobically digested slurry in late May-early June 1993 and 1994. Ammonia volatilization was measured using a windtunnel system for a period of 8 days after slurry application. Denitrification was measured for a period of 21 days after slurry application. In an adjacent field experiment, nitrogen-uptake (N-uptake) was determined in the first two cuts of the ryegrass harvested after slurry application. N losses through ammonia volatilization were larger in 1993 than in 1994 due to differences in climatic conditions. Ammonia volatilization was lowered substantially (47–72%), when slurry was injected compared with surface application. In 1993 the loss from surface-applied digested slurry was only 35% of total ammoniacal nitrogen (TAN), while the loss from the raw slurry was 47%. There were no significant differences in ammonia volatilization from the two slurry types in the other experiments. N losses through denitrification were low (< 2% of TAN), but there were clear differences in the losses, depending on slurry type, application method and experimental year. Injection of the slurry gave a larger N-uptake in the first cut of grass compared to the trail-hose application. In 1993 N-uptake from the digested slurry treatment gave significantly larger N-uptake compared to the raw slurry in the first cut.

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Enteric methane emission estimates for Kenyan cattle in a nighttime enclosure using a backward Lagrangian Stochastic dispersion technique

Theoretical and Applied Climatology ◽

10.1007/s00704-021-03868-7 ◽

2021 ◽

Author(s):

Kevin Wolz ◽

Sonja Leitner ◽

Lutz Merbold ◽

Benjamin Wolf ◽

Matthias Mauder

Keyword(s):

Developed Countries ◽

Mature Female ◽

Dispersion Modeling ◽

Intergovernmental Panel ◽

Open Path ◽

Tier 1 ◽

Sub Saharan ◽

Dispersion Technique ◽

Semi Arid Region ◽

Further Development

AbstractThis study provides methane (CH4) emission estimates for mature female African beef cattle in a semi-arid region in Southern Kenya using open-path laser spectroscopy together with a backward Lagrangian Stochastic (bLS) dispersion modeling technique. We deployed two open-path lasers to determine 10-min averages of line-integrated CH4 measurements upwind and downwind of fenced enclosures (so-called bomas: a location where the cattle are gathered at night) during 14 nights in September/October 2019. The measurements were filtered for wind direction deviations and friction velocity before the model was applied. We compared the obtained emission factors (EFs) with the Intergovernmental Panel on Climate Change (IPCC) Tier 1 estimates for the Sub-Saharan African (SSA) countries, which were mostly derived from studies carried out in developed countries and adapted to the conditions in Africa. The resulting EF of 75.4 ± 15.99 kg year−1 and the EFs calculated from other studies carried out in Africa indicate the need for the further development of region-specific EFs depending on animal breed, livestock systems, feed quantity, and composition to improve the IPCC Tier 1 estimates.

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Quantifying fugitive gas emissions from an oil sands tailings pond with open-path Fourier transform infrared measurements

Atmospheric Measurement Techniques ◽

10.5194/amt-14-945-2021 ◽

2021 ◽

Vol 14 (2) ◽

pp. 945-959

Author(s):

Yuan You ◽

Samar G. Moussa ◽

Lucas Zhang ◽

Long Fu ◽

James Beck ◽

...

Keyword(s):

Fourier Transform ◽

Oil Sands ◽

Measurement Techniques ◽

Flux Measurement ◽

Fourier Transform Infrared ◽

Inverse Dispersion ◽

Nh3 Emission ◽

Open Path ◽

Infrared Measurements ◽

Emission Fluxes

Abstract. Fugitive emissions from tailings ponds contribute significantly to facility emissions in the Alberta oil sands, but details on chemical emission profiles and the temporal and spatial variability of emissions to the atmosphere are sparse, since flux measurement techniques applied for compliance monitoring have their limitations. In this study, open-path Fourier transform infrared spectroscopy was evaluated as a potential alternative method for quantifying spatially representative fluxes for various pollutants (methane, ammonia, and alkanes) from a particular pond, using vertical-flux-gradient and inverse-dispersion methods. Gradient fluxes of methane averaged 4.3 g m−2 d−1 but were 44 % lower than nearby eddy covariance measurements, while inverse-dispersion fluxes agreed to within 30 %. With the gradient fluxes method, significant NH3 emission fluxes were observed (0.05 g m−2 d−1, 42 t yr−1), and total alkane fluxes were estimated to be 1.05 g m−2 d−1 (881 t yr−1), representing 9.6 % of the facility emissions.

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Performance of open-path GasFinder3 devices for CH<sub>4</sub> concentration measurements close to ambient levels

Atmospheric Measurement Techniques ◽

10.5194/amt-14-1733-2021 ◽

2021 ◽

Vol 14 (2) ◽

pp. 1733-1741

Author(s):

Christoph Häni ◽

Marcel Bühler ◽

Albrecht Neftel ◽

Christof Ammann ◽

Thomas Kupper

Keyword(s):

Closed Path ◽

Laser Device ◽

Dispersion Method ◽

Quantum Cascade ◽

Inverse Dispersion ◽

Open Path ◽

Hourly Data ◽

Concentration Enhancement ◽

Emission Estimation ◽

Ambient Levels

Abstract. Open-path measurements of methane (CH4) with the use of GasFinder systems (Boreal Laser Inc, Edmonton Canada) have been frequently used for emission estimation with the inverse dispersion method (IDM), particularly from agricultural sources. It is common to many IDM applications that the concentration enhancement related to CH4 sources is small, typically between 0.05 and 0.5 ppm, and accurate measurements of CH4 concentrations are needed at concentrations close to ambient levels. The GasFinder3-OP (GF3) device for open-path CH4 measurements is the latest version of the commercial GasFinder systems by Boreal Laser Inc. We investigated the uncertainty of six GF3 devices from side-by-side intercomparison measurements and comparisons to a closed-path quantum cascade laser device. The comparisons were made at near-ambient levels of CH4 (85 % of measurements below 2.5 ppm) with occasional phases of elevated concentrations (max. 8.3 ppm). Relative biases as high as 8.3 % were found, and a precision for half-hourly data between 2.1 and 10.6 ppm-m (half width of the 95 % confidence interval) was estimated. These results deviate from the respective manufacturer specifications of 2 % and 0.5 ppm-m. Intercalibration of the GF3 devices by linear regression to remove measurement bias was shown to be of limited value due to drifts and step changes in the recorded GF3 concentrations.

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Reactive Nitrogen Releases And Nitrogen Footprint During The Life-Cycles of Intensive Vegetable Production Affected By Human Feces Slurry Substitution

10.21203/rs.3.rs-825961/v1 ◽

2021 ◽

Author(s):

Yang Bo ◽

Zhang Tao ◽

Zhang Man ◽

Bo Li

Keyword(s):

Treatment Group ◽

Life Cycles ◽

Inorganic Fertilizer ◽

Reactive Nitrogen ◽

Vegetable Production ◽

Fertilizer N ◽

Human Feces ◽

Gaseous Nitrogen ◽

Nitrogen Emissions ◽

Economic Income

Abstract Evaluating the sustainability of vegetable production is crucial to secure future food supply. A two-year field study of four different vegetable crops was performed to investigate the effects of inorganic fertilizer and human feces slurry at different ratios on vegetable yields, reactive gaseous nitrogen emissions (GNrEs), reactive nitrogen (Nr) footprint and net ecosystem-economic income (NEEI) by using life-cycle analysis. Four fertilization strategies were studied, including: CK (no fertilization); CF (inorganic fertilization); CHF1 (human feces slurry/inorganic fertilizer, N ratio=1:7); and CHF2 (human slurry/inorganic fertilizer, N ratio=1:3). Results showed that compared with CF treatment, both CHF1 and CHF2 treatments increased the N2O+NO emissions by 11.8 % and 32.4 % on average, while decreased the vegetable yields by 6.7 % and 7.4 %, respectively. Moreover, the addition of human feces slurry increased the proportions of Nr footprint by 6.6 % (CHF1) and 2.9 % (CHF2) in comparison with CF treatment group. However, although CHF2 treatment significantly increased the values of GNrEs and reactive gaseous nitrogen intensity (GNrI) by 8.4 % and 12.5 %, respectively, in relation to those in CF treatment group, it still increased farmers’ income by 16,404 CNY ha−1. These findings suggest that although human feces slurry incorporation could not mitigate Nr releases, the appropriate ratio of inorganic fertilizer and human feces slurry (CHF2) is able to improve net economic income (NEI) and NEEI during intensive vegetable production. Nevertheless, the relationship between combinatorial treatment of inorganic fertilizer and human feces slurry and mitigation of Nr release should be explored further.

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Gaseous Nitrogen Loss from Soybean Foliage 1

Agronomy Journal ◽

10.2134/agronj1979.00021962007100010024x ◽

1979 ◽

Vol 71 (1) ◽

pp. 95-97 ◽

Cited By ~ 51

Author(s):

C. A. Stutte ◽

R. T. Weiland ◽

A. R. Blem

Keyword(s):

Nitrogen Loss ◽

Gaseous Nitrogen

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