Estimation of Greenhouse Gases Emitted from Energy Industry (Oil Refining and Electricity Generation) in Iraq Using IPCC Methodology

The energy sector is integral to the wellbeing of the entire Iraqi economy and will remain so well into the future. In the current study, the Intergovernmental Panel on Climate Change (IPCC) methodology was used to estimate CO2, CH4, and N2O emissions from oil refining and electricity generation in Iraq for a period exceeding 25 years. From 1990, Iraq experienced two wars and an economic siege, then faced political, social, and security instability, which affected its energy production. The results showed that the CO2, CH4, and N2O emissions from the oil refining and electricity generation in Iraq experienced a sharp decline in the years 1991, 2003, and 2007 due to a decrease in the production of oil derivatives in refineries, according to political and security conditions. The total CO2 emissions from the types of fuel used in electricity generation in Iraq was approximately 14,000 Gg and 58,000 Gg in 1990 and 2017, respectively. The increase in CO2 emissions was greater than 300% between 1990 and 2017. The continued use of poor types of fuel, such as fuel oil and crude oil, will lead to an increase in greenhouse gas (GHG) emissions from these sources, and higher levels of environmental pollution.

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Greenhouse gases emissions from riparian wetlands: an example from the Inner Mongolia grassland region in China

Biogeosciences ◽

10.5194/bg-18-4855-2021 ◽

2021 ◽

Vol 18 (17) ◽

pp. 4855-4872

Author(s):

Xinyu Liu ◽

Xixi Lu ◽

Ruihong Yu ◽

Heyang Sun ◽

Hao Xue ◽

...

Keyword(s):

Co2 Emissions ◽

Anthropogenic Activities ◽

Ghg Emissions ◽

Spatiotemporal Pattern ◽

N2o Emissions ◽

Riparian Wetlands ◽

Wet Season ◽

Riparian Wetland ◽

Ch4 And N2o ◽

The Impact

Abstract. Gradual riparian wetland drying is increasingly sensitive to global warming and contributes to climate change. Riparian wetlands play a significant role in regulating carbon and nitrogen cycles. In this study, we analyzed the emissions of carbon dioxide (CO2), methane (CH4), and nitrous oxide (N2O) from riparian wetlands in the Xilin River basin to understand the role of these ecosystems in greenhouse gas (GHG) emissions. Moreover, the impact of the catchment hydrology and soil property variations on GHG emissions over time and space was evaluated. Our results demonstrate that riparian wetlands emit larger amounts of CO2 (335–2790 mgm-2h-1 in the wet season and 72–387 mgm-2h-1 in the dry season) than CH4 and N2O to the atmosphere due to high plant and soil respiration. The results also reveal clear seasonal variations and spatial patterns along the transects in the longitudinal direction. N2O emissions showed a spatiotemporal pattern similar to that of CO2 emissions. Near-stream sites were the only sources of CH4 emissions, while the other sites served as sinks for these emissions. Soil moisture content and soil temperature were the essential factors controlling GHG emissions, and abundant aboveground biomass promoted the CO2, CH4, and N2O emissions. Moreover, compared to different types of grasslands, riparian wetlands were the potential hotspots of GHG emissions in the Inner Mongolian region. Degradation of downstream wetlands has reduced the soil carbon pool by approximately 60 %, decreased CO2 emissions by approximately 35 %, and converted the wetland from a CH4 and N2O source to a sink. Our study showed that anthropogenic activities have extensively changed the hydrological characteristics of the riparian wetlands and might accelerate carbon loss, which could further affect GHG emissions.

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Greenhouse gas emissions from fen soils used for forage production in northern Germany

Biogeosciences ◽

10.5194/bg-13-5221-2016 ◽

2016 ◽

Vol 13 (18) ◽

pp. 5221-5244 ◽

Cited By ~ 15

Author(s):

Arne Poyda ◽

Thorsten Reinsch ◽

Christof Kluß ◽

Ralf Loges ◽

Friedhelm Taube

Keyword(s):

Ghg Emissions ◽

Farming Systems ◽

Forage Yield ◽

N2o Emissions ◽

Net Energy ◽

Forage Production ◽

Climatic Impact ◽

Northern Germany ◽

Ch4 And N2o

Abstract. A large share of peatlands in northwestern Germany is drained for agricultural purposes, thereby emitting high amounts of greenhouse gases (GHGs). In order to quantify the climatic impact of fen soils in dairy farming systems of northern Germany, GHG exchange and forage yield were determined on four experimental sites which differed in terms of management and drainage intensity: (a) rewetted and unutilized grassland (UG), (b) intensive and wet grassland (GW), (c) intensive and moist grassland (GM) and (d) arable forage cropping (AR). Net ecosystem exchange (NEE) of CO2 and fluxes of CH4 and N2O were measured using closed manual chambers. CH4 fluxes were significantly affected by groundwater level (GWL) and soil temperature, whereas N2O fluxes showed a significant relation to the amount of nitrate in top soil. Annual balances of all three gases, as well as the global warming potential (GWP), were significantly correlated to mean annual GWL. A 2-year mean GWP, combined from CO2–C eq. of NEE, CH4 and N2O emissions, as well as C input (slurry) and C output (harvest), was 3.8, 11.7, 17.7 and 17.3 Mg CO2–C eq. ha−1 a−1 for sites UG, GW, GM and AR, respectively (standard error (SE) 2.8, 1.2, 1.8, 2.6). Yield-related emissions for the three agricultural sites were 201, 248 and 269 kg CO2–C eq. (GJ net energy lactation; NEL)−1 for sites GW, GM and AR, respectively (SE 17, 9, 19). The carbon footprint of agricultural commodities grown on fen soils depended on long-term drainage intensity rather than type of management, but management and climate strongly influenced interannual on-site variability. However, arable forage production revealed a high uncertainty of yield and therefore was an unsuitable land use option. Lowest yield-related GHG emissions were achieved by a three-cut system of productive grassland swards in combination with a high GWL (long-term mean ≤  20 cm below the surface).

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The Evaluation of the Levels of Greenhouse Gases due to Activities Carried Out on a Livestock Farm

Revista de Chimie ◽

10.37358/rc.17.8.5747 ◽

2017 ◽

Vol 68 (8) ◽

pp. 1700-1702

Author(s):

Valeriu Danciulescu ◽

Andrei Vasile ◽

Luoana Florentina Pascu ◽

Bogdan Stanescu ◽

Ileana Nicolescu

Keyword(s):

Agricultural Sector ◽

Ghg Emissions ◽

Pollutant Dispersion ◽

Ambient Air ◽

N2o Emissions ◽

Measured Temperature ◽

Animal Shelters ◽

Livestock Sector ◽

Land Cultivation ◽

Ch4 And N2o

The paper presents the results of tests carried out on a Romanian farm with the purpose of assessing greenhouse gas (GHG) emissions specific to agricultural activities. GHG emissions from the agricultural sector come mainly from the livestock sector, manure management, land cultivation and fertilization. The tests carried out mainly focused on the CO2 , CH4 and N2O emissions generated from related manure storage activities as well as the emission level identified in animal shelters. For a correct interpretation of the results obtained, at the same time with the measurement of the GHG concentration, the weather parameters were measured: temperature, humidity and wind direction. The results obtained revealed the presence of these compounds in the air in the animal shelters and in the ambient air (CO2 and CH4) in concentrations that are in the range identified in similar studies around the world. The pollutant dispersion in the air leads to a reduction in the pollutant concentration with increasing distance from the observed source as well as the measurement points at 50, 100 and 500 m, that reaches values below the detection limit of the instrument for CH4 and N2O, whereas in the case of CO2 it reaches the level of the usual concentration in the ambient air.

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Emisi Gas Rumah Kaca dan Hasil Padi dari Cara Olah Tanah dan Pemberian Herbisida Di Lahan Sawah MK 2015

Jurnal Ilmu Lingkungan ◽

10.14710/jil.15.2.74-82 ◽

2018 ◽

Vol 15 (2) ◽

pp. 74 ◽

Cited By ~ 3

Author(s):

Miranti Ariani ◽

Hesti Yulianingrum ◽

Prihasto Setyanto

Keyword(s):

Rice Yield ◽

Ghg Emissions ◽

Conservation Agriculture ◽

Soil Disturbance ◽

N2o Emissions ◽

No Tillage ◽

Zero Tillage ◽

Deep Tillage ◽

Tillage Treatment ◽

Ch4 And N2o

Tanpa olah tanah (NT) telah banyak ditunjukkan sebagai praktik pengelolaan lahan sawah yang mampu mengurangi emisi gas rumah kaca (GRK) karena kemampuannya untuk menyerap karbon dalam tanah. Di luar negeri, bahkan juga oleh FAO, sekarang ini sedang banyak dikembangkan apa yang disebut dengan conservation agriculture, yaitu cara bercocok tanam dengan meminimalkan gangguan pada tanah atau dikenal juga dengan istilah No tillage/Zero Tillage (tanpa olah tanah). Penelitian ini bertujuan untuk memperoleh informasi emisi CH4 dan N2O dari lahan sawah di daerah tropis dengan perlakuan cara olah tanah. Percobaan disusun dengan rancangan faktorial acak kelompok 3 ulangan. Perlakuan yang dicobakan terdiri dari 2 faktor, yaitu faktor I cara olah tanah (1) Olah tanah sempurna, (2) tanpa olah tanah, dan faktor II adalah pemberian herbisida berupa (1) glifosat, (2) paraquat dan (3) tanpa herbisida. Jarak tanam adalah tegel 20 cm x 20 cm. Emisi CH4 pada MK 2015 yang terendah adalah pada perlakuan tanpa olah tanah (TOT) dan pemberian herbisida glifosat, yaitu sebesar 201 kg CH4/ha/musim dan yang tertinggi pada perlakuan olah tanah sempurna tanpa penambahan herbisida yaitu sebesar 353 kg CH4/ha/musim. Tanpa olah tanah menghasilkan rerata fluks harian CH4 yang lebih rendah dibanding perlakuan olah tanah sempurna. Emisi N2O terendah dihasilkan pada perlakuan olah tanah sempurna dengan penambahan herbisida glifosat, yaitu sebesar 0,34 kg N2O/ha/musim, dan tertinggi pada perlakuan tanpa olah tanah dengan penambahan herbisida paraquat yaitu sebesar 0,65 kg N2O/ha/musim. Hasil padi pada semua perlakuan menunjukkan nilai yang tidak berbeda nyata. Faktor emisi N2O langsung dari lahan padi sawah irigasi dengan perlakuan olah tanah dan herbisida berkisar antara 0,0008 – 0,0015 kg N2O-N/kg N dengan kisaran hasil padi sebesar 4,96 – 5,12 t/ha GKG. Secara total, yang dinyatakan dengan GWP, perlakuan tanpa olah tanah menimbulkan emisi GRK yang lebih kecil dibanding perlakuan olah tanah sempurnaKata kunci: olah tanah, herbisida, GWP, CH4, N2OABSTRACTNo-tillage (NT) management has been promoted as a practice capable of offsetting greenhouse gas (GHG) emissions because of its ability to sequester carbon in soils. Even FAO and many countries, are now being widely developed what so called conservation agriculture, on how to grow crops with minimize soil disturbance or also known as No tillage/Zero tillage. This study aimed to obtain information CH4 and N2O emissions and grain yield from rice fields in the tropics with tillage treatments. The experiment was arranged in a randomized factorial design with 3 replications. The treatments tested consisted of two factors, namely the first factor was tillage (1) deep tillage, (2) zero tillage, and the second factor is application of herbicide in the form of (1) glyphosate, (2) paraquat and (3) without herbicides, using tiles row spacing (20 x 20 cm). In DS 2015, the lowest CH4 emissions resulted from no-tillage (TOT) treatment combined with the application of glyphosate, which amounted to 201 kg CH4/ha/ season and the highest resulted from deep tillage treatment combined with no herbicide, which amounted to 353 kg CH4/ha/season. Daily CH4 fluxes from No tillage treatment are lower than those from deep tillage treatments. The lowest N2O emissions resulted from deep tillage treatments combined with the application of glyphosate, which amounted to 0.34 kg N2O/ha/season, and the highest resulted from no-tillage treatment combined with paraquat, which amounted to 0.65 kg N2O/ha/season. Rice yield were not significantly different among treatments. Direct N2O factors emissions from irrigated rice field applied tillage and herbicide treatments ranged from 0.0008 to 0.0015 kg N2O-N/kg N with rice yield range of 4.96 to 5.12 t/ha. In total, expressed by GWP, no tillage treatment resulted lower GHG emissions than deep tillage treatments.Keywords: tillage, herbicide, GWP, CH4, N2OCitation: Ariani, M., Yulianingrum, H. dan Setyanto, P. (2017). Emisi Gas Rumah Kaca dan Hasil Padi dari Cara Olah Tanah dan Pemberian Herbisida Di Lahan Sawah MK 2015. Jurnal Ilmu Lingkungan, 15(2), 74-82, doi:10.14710/jil.15.2.74-82

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Animal nutrition strategies to reduce greenhouse gas emissions in dairy cattle

Acta Universitaria ◽

10.15174/au.2018.1766 ◽

2018 ◽

Vol 28 (5) ◽

pp. 34-41

Author(s):

Juan Antonio Rendon-Huerta ◽

Juan Manuel Pinos-Rodríguez ◽

Ermias Kebreab

Keyword(s):

Dairy Cattle ◽

Greenhouse Gas ◽

Dietary Protein ◽

Ghg Emissions ◽

N2o Emission ◽

Nitrogen Excretion ◽

Animal Nutrition ◽

Intergovernmental Panel ◽

Ch4 And N2o ◽

Forage:Concentrate Ratio

The objective of this study was to analyze different animal nutrition strategies from published papers to reduce greenhouse gas (GHG) emissions, particularly methane (CH4) and nitrous oxide (N2O) in dairy cattle. Ration data used (n = 32 diets) was obtained from 15 published papers selected according to differences between forage:concentrate ratio and crude protein (CP) content. An empirical model was used to estimate enteric methane emissions based on fiber and CP content in the diets. The N2O emission was calculated according to Intergovernmental Panel of Climate Change (IPCC) recommendations. Differences between CH4 and N2O affected by FC or CP content were analyzed through a variance analysis. Furthermore, a correlation analysis was carried out to compare CP content and nitrogen excretion in feces, urine and milk. Estimations of enteric CH4 were not significantly different between diets with various forage content levels. Diets with high concentrate content had lower GHG intensity. Nitrogen excretion in feces and urine increased linearly as dietary protein level was increased from the lowest to the highest concentrations, but conversion of nitrogen intake to nitrogen excreted in milk was not affected by increasing dietary protein. In conclusion, dietary manipulation could decrease GHG emissions by unit of produced milk.

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Greenhouse gas emissions from fen soils used for forage production in northern Germany

10.5194/bg-2015-635 ◽

2016 ◽

Author(s):

Arne Poyda ◽

Thorsten Reinsch ◽

Christof Kluß ◽

Ralf Loges ◽

Friedhelm Taube

Keyword(s):

Ghg Emissions ◽

Forage Yield ◽

N2o Emissions ◽

Net Energy ◽

Forage Production ◽

Climatic Impact ◽

Northern Germany ◽

Northwest Germany ◽

Ch4 And N2o

Abstract. A large share of peatlands in northwest Germany is drained for agricultural purposes, thereby emitting high amounts of greenhouse gases (GHG). In order to quantify the climatic impact of fen soils in dairy farming systems of northern Germany, GHG exchange and forage yield were determined on four experimental sites which differed in terms of management and drainage intensity: a) rewetted and unutilized grassland (UG), b) intensive and 'wet' grassland (GW), c) intensive and 'moist' grassland (GM) and d) arable forage cropping (AR). Net ecosystem exchange (NEE) of CO2 and fluxes of CH4 and N2O were measured using closed manual chambers. CH4 fluxes were significantly affected by groundwater level (GWL) and soil temperature, whereas N2O fluxes showed a significant relation to the amount of nitrate in top soil. Annual balances of all three gases, as well as the global warming potential (GWP), were significantly correlated to mean annual GWL. Two-year mean GWP, combined from C2-C-equivalents of NEE, CH4 and N2O emissions, as well as C input (slurry) and C output (harvest), was 3.8, 11.7, 17.7 and 17.3 Mg CO2-C-eq ha−1 a−1 for sites UG, GW, GM and AR, respectively (standard error (SE) 2.8, 1.2, 1.8, 2.6). Yield related emissions for the three agricultural sites were 201, 248 and 269 kg CO2-C-eq (GJ net energy lactation (NEL))−1 for sites GW, GM and AR, respectively (SE 17, 9, 19). The carbon footprint of agricultural commodities grown on fen soils depended on long-term drainage intensity rather than type of management, but management and climate strongly influenced interannual on-site variability. However, arable forage production revealed a high uncertainty of yield and therefore was an unsuitable land use option. Lowest yield related GHG emissions were achieved by a three-cut system of productive grassland swards in combination with a high GWL (long-term mean ≤ 20 cm below the surface).

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Modelling the influence of soil carbon on net greenhouse gas emissions from grazed pastures

Animal Production Science ◽

10.1071/an15508 ◽

2016 ◽

Vol 56 (3) ◽

pp. 585 ◽

Cited By ~ 6

Author(s):

Rachelle Meyer ◽

Brendan R. Cullen ◽

Richard J. Eckard

Keyword(s):

Organic Matter ◽

Soil Organic Matter ◽

Annual Variation ◽

Ghg Emissions ◽

C Sequestration ◽

N2o Emissions ◽

Soil C ◽

High Rainfall ◽

Sequestration Potential ◽

Ch4 And N2o

Sequestering carbon (C) in soil organic matter in grassland systems is often cited as a major opportunity to offset greenhouse gas (GHG) emissions. However, these systems are typically grazed by ruminants, leading to uncertainties in the net GHG balance that may be achieved. We used a pasture model to investigate the net balance between methane (CH4), nitrous oxide (N2O) and soil C in sheep-grazed pasture systems with two starting amounts of soil C. The net emissions were calculated for four soil types in two rainfall zones over three periods of 19 years. Because of greater pasture productivity, and consequent higher sheep stocking rates, high-rainfall sites were associated with greater GHG emissions that could not be offset by C sequestration. On these high-rainfall sites, the higher rate of soil organic carbon (SOC) increase on low-SOC soils offset an average of 45% of the livestock GHG emissions on the modelled chromosol and 32% on the modelled vertosol. The slow rate of SOC increase on the high-SOC soils only offset 2–4% of CH4 and N2O emissions on these high-rainfall sites. On low-rainfall sites, C sequestration in low-SOC soils more than offset livestock GHG emissions, whereas the modelled high-C soils offset 75–86% of CH4 and N2O emissions. Greater net emissions on high-C soils were due primarily to reduced sequestration potential and greater N2O emissions from nitrogen mineralisation and livestock urine. Annual variation in CH4 and N2O emissions was low, whereas annual SOC change showed high annual variation, which was more strongly correlated with weather variables on the low-rainfall sites compared with the high-rainfall sites. At low-soil C concentrations, with high sequestration potential, there is an initial mitigation benefit that can in some instances offset enteric CH4 and direct and indirect N2O emissions. However, as soil organic matter increases there is a trade-off between diminishing GHG offsets and increasing ecosystem services, including mineralisation and productivity benefits.

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Energy efficiency and emissions of CO2, CH4, and N2O in organic and conventional rice production

Semina Ciências Agrárias ◽

10.5433/1679-0359.2020v41n3p797 ◽

2020 ◽

Vol 41 (3) ◽

pp. 797

Author(s):

Roni Fernandes Guareschi ◽

Marcio dos Reis Martins ◽

Segundo Urquiaga ◽

Bruno José Rodrigues Alves ◽

Robert Michael Boddey ◽

...

Keyword(s):

Energy Efficiency ◽

Total Energy ◽

Ghg Emissions ◽

Primary Energy ◽

Rice Production ◽

Production Costs ◽

Energy Output ◽

Intergovernmental Panel ◽

Production Cycles ◽

Ch4 And N2o

Rice is the second-most produced cereal worldwide and actively contributes to greenhouse gas (GHG) emissions, particularly methane, especially under deepwater production. Assessments of energy efficiency (EE) and GHG emissions can indicate the sustainability level of agrosystems and support decisions related to the reduction of production costs and environmental pollution. This study aimed to assess both EE and GHG emissions in organic and conventional rice production in the Southern region of Brazil. For this study, eight rice fields were evaluated. Energy inputs and outputs were calculated by multiplying the production input amounts by their respective calorific values or energy coefficients at each stage of production. EE was determined using the ratio between the total energy output and the total energy consumed during the production process. GHG emissions were estimated using the principles of the lifecycle assessment methodology in addition to the Intergovernmental Panel on Climate Change (IPCC) recommendations. Each 1.0 MJ consumed during the production of organic and conventional rice produced renewable energy averages of 10.5 MJ and 7.90 MJ, respectively, as grains. The primary energy expenses for organic rice were represented by seeds, fuel, tractors, and agricultural machinery and implements, and those for conventional rice were seeds, fuel, and fertilizers. Each kilogram of organic and conventional rice produced accounted for the emission of 0.21 and 0.32 kg of CO2eq, respectively, during the production cycles and delivery to the warehouse, with seeds, fuel, and fertilizers being the main sources of CO2eq emissions to the atmosphere.

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EMISIÓN DE METANO Y ÓXIDO NITROSO DE LOS SEDIMENTOS DE MANGLAR DE LA CIÉNAGA GRANDE DE SANTA MARTA, CARIBE COLOMBIANO

Bulletin of Marine and Coastal Research ◽

10.25268/bimc.invemar.2013.42.1.64 ◽

2016 ◽

Vol 42 (1) ◽

Author(s):

Julián Mauricio Betancourt Portela ◽

Juan Pablo Parra ◽

Carlos Villamil

Keyword(s):

Ghg Emissions ◽

N2o Emissions ◽

Mangrove Forests ◽

Agricultural Systems ◽

Release Rates ◽

Mangrove Sediments ◽

Ch4 And N2o ◽

Magdalena River ◽

Global Carbon

In Colombia there is little information on the role of mangroves in relation to greenhouse gases (GHG), their release rates under different environmental conditions, or their role in the global carbon cycle. For these reasons, in this study we evaluated the fluxes of CH4 and N2O, in four sectors of the Ciénaga Grande de Santa Marta (CGSM) with different degrees of conservation of mangrove forests, to determine their role as a source or sink of GHG. The fluxes were measured by the method of the static chambers and showed variations between 34.7-1179.7 and nd-31569.2 μg.m-2.h-1 for N2O and CH4, respectively, showing that mangrove sediments of CGSM are a net source of GHG, and furthermore are of the same magnitude as levels recorded world-wide in mangroves subjected to sewage input. Statistical analyses showed differences between sectors but not between climatic periods. N2O emissions were highest in the Agua Negras station (AN, 847.3 ± 265.7 μg.m-2.h-1), a locality in the process of natural regeneration with a direct influence from the Magdalena River and in Caño Dragado (CD, 438.7 ± 235.3 μg.m-2.h-1); while emissions were lower in the recovery sites Caño Grande (CG) and Rinconada (RIN), (104.7 ± 49.4 and 152.1 ± 36.0 μg.m-2.h-1, respectively). The highest CH4 emission was recorded in recovery sectors: CG and AN (9573.4 ± 8623.8 and 4328.2 ± 7569.5 μg.m-2.h-1, respectively). In terms of CO2-equivalent, N2O emissions account for over 50% of the total, and this has been documented for agricultural systems and constitutes evidence of deterioration of CD. A correlation analysis with environmental factors showed that N2O emissions vary inversely with salinity and positively with nitrites, suggesting production mainly via nitrification. Finally, a coarse estimation of GHG emissions per hectare indicated that, depending on the state of conservation or deterioration of the mangrove, emissions can vary from 10.2 to 27.1 tCO2-eq.ha-1.a-1.

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Soil greenhouse gas emissions under different land-use types in savanna ecosystems of Kenya

Biogeosciences ◽

10.5194/bg-17-2149-2020 ◽

2020 ◽

Vol 17 (8) ◽

pp. 2149-2167 ◽

Cited By ~ 3

Author(s):

Sheila Wachiye ◽

Lutz Merbold ◽

Timo Vesala ◽

Janne Rinne ◽

Matti Räsänen ◽

...

Keyword(s):

Land Use ◽

Soil Moisture ◽

Co2 Emissions ◽

Vegetation Cover ◽

Ghg Emissions ◽

N2o Emissions ◽

Grazing Land ◽

Soil C ◽

Land Use Types ◽

Soil Co2 Emissions

Abstract. Field measurement data on greenhouse gas (GHG) emissions are still scarce for many land-use types in Africa, causing a high level of uncertainty in GHG budgets. To address this gap, we present in situ measurements of carbon dioxide (CO2), nitrous oxide (N2O), and methane (CH4) emissions from the lowlands of southern Kenya. We conducted eight chamber measurement campaigns on gas exchange from four dominant land-use types (LUTs) comprising (1) cropland, (2) bushland, (3) grazing land, and (4) conservation land between 29 November 2017 and 3 November 2018, accounting for regional seasonality (wet and dry seasons and transitions periods). Mean CO2 emissions for the whole observation period were the highest by a significant margin (p value < 0.05) in the conservation land (75±6 mg CO2-C m−2 h−1) compared to the three other sites, which ranged from 45±4 mg CO2-C m−2 h−1 (bushland) to 50±5 mg CO2-C m−2 h−1 (grazing land). Furthermore, CO2 emissions varied between seasons, with significantly higher emissions in the wet season than the dry season. Mean N2O emissions were highest in cropland (2.7±0.6 µg N2O-N m−2 h−1) and lowest in bushland (1.2±0.4 µg N2O-N m−2 h−1) but did not vary with season. In fact, N2O emissions were very low both in the wet and dry seasons, with slightly elevated values during the early days of the wet seasons in all LUTs. On the other hand, CH4 emissions did not show any significant differences across LUTs and seasons. Most CH4 fluxes were below the limit of detection (LOD, ±0.03 mg CH4-C m−2 h−1). We attributed the difference in soil CO2 emissions between the four sites to soil C content, which differed between the sites and was highest in the conservation land. In addition, CO2 and N2O emissions positively correlated with soil moisture, thus an increase in soil moisture led to an increase in emissions. Furthermore, vegetation cover explained the seasonal variation in soil CO2 emissions as depicted by a strong positive correlation between the normalized difference vegetation index (NDVI) and CO2 emissions, most likely because, with more green (active) vegetation cover, higher CO2 emissions occur due to enhanced root respiration compared to drier periods. Soil temperature did not show a clear correlation with either CO2 or N2O emissions, which is likely due to the low variability in soil temperature between seasons and sites. Based on our results, soil C, active vegetation cover, and soil moisture are key drivers of soil GHG emissions in all the tested LUTs in southern Kenya. Our results are within the range of previous GHG flux measurements from soils from various LUTs in other parts of Kenya and contribute to more accurate baseline GHG emission estimates from Africa, which are key to reducing uncertainties in global GHG budgets as well as for informing policymakers when discussing low-emission development strategies.

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