scholarly journals Short-term effects of biogas digestate and cattle slurry application on greenhouse gas emissions from high organic carbon grasslands

2014 ◽  
Vol 11 (4) ◽  
pp. 5765-5809 ◽  
Author(s):  
T. Eickenscheidt ◽  
A. Freibauer ◽  
J. Heinichen ◽  
J. Augustin ◽  
M. Drösler
Keyword(s):  
Organic Carbon ◽  
Application Rate ◽  
Organic Fertilizers ◽  
Organic Soils ◽  
N2o Emissions ◽  
Cattle Slurry ◽  
Closed Chamber ◽  
Chamber Method ◽  
Biogas Digestate ◽  
N2o Fluxes

Abstract. The change in the German energy policy resulted in a strong development of biogas plants in Germany. As a consequence, huge amounts of nutrient rich residues remain from the fermentative process, which are used as organic fertilizers. Drained peatlands are increasingly used to satisfy the huge demand for fermentative substrates and the digestate is returned to the peatlands. However, drained organic soils are considered as hot spots for nitrous oxide (N2O) emissions and organic fertilization is additionally known to increase N2O emissions from managed grasslands. Our study addressed the questions (a) to what extent biogas digestate and cattle slurry application increase N2O, methane (CH4) and ammonia (NH3) fluxes as well as the mineral nitrogen use efficiency (NUEmin), and (b) how different soil organic matter contents (SOM) promote the production of N2O. The study was conducted at two areas within a grassland parcel, which differed in their soil organic carbon (SOC) contents. At each area (named Corg-medium and Corg-high) two sites were established, one was fertilized five times with biogas digestate and one with cattle slurry. For each treatment, fluxes of N2O and CH4 were measured over two years using the closed chamber method. For NH3 measurements we used the calibrated dynamic chamber method. On an annual basis the application of biogas digestate significantly enhanced the N2O fluxes compared to the application of cattle slurry and additionally increased the NUEmin. Furthermore, N2O fluxes from the Corg-high site significantly exceeded N2O fluxes from the Corg-medium sites. Annual cumulative emissions ranged from 0.91 ± 0.49 kg N ha−1 yr−1 to 3.14 ± 0.91 kg N ha−1 yr−1. Significantly different CH4 fluxes between the investigated treatments or the different soil types were not observed. Cumulative annual CH4 exchange rates varied between −0.21 ± 0.19 kg C ha−1 yr−1 and −1.06 ± 0.46 kg C ha−1 yr−1. Significantly higher NH3 losses from treatments fertilized with biogas digestate compared to those fertilized with cattle slurry were observed. The total NH3 losses following splash plate application were 18.17 kg N ha−1 for the digestate treatments and 3.48 kg N ha−1 for the slurry treatments (36% and 15% of applied NH4+-N). The observed linear increase of 16 days cumulative N2O-N exchange or rather annual N2O emissions, due to a higher mean groundwater level and a higher application rate of NH4+-N, reveal the importance of site adapted N fertilization and the avoidance of N surpluses in Corg rich grasslands.

scholarly journals Short-term effects of biogas digestate and cattle slurry application on greenhouse gas emissions affected by N availability from grasslands on drained fen peatlands and associated organic soils

2014 ◽  
Vol 11 (22) ◽  
pp. 6187-6207 ◽  
Author(s):  
T. Eickenscheidt ◽  
A. Freibauer ◽  
J. Heinichen ◽  
J. Augustin ◽  
M. Drösler
Keyword(s):  
N Uptake ◽  
Organic Fertilizers ◽  
Strong Increase ◽  
Organic Soils ◽  
N2o Emissions ◽  
N Availability ◽  
Cattle Slurry ◽  
Chamber Method ◽  
Biogas Digestate ◽  
N2o Fluxes

Abstract. A change in German energy policy has resulted in a strong increase in the number of biogas plants in Germany. As a consequence, huge amounts of nutrient-rich residues, the by-products of the fermentative process, are used as organic fertilizers. Drained peatlands are increasingly used to satisfy the huge demand for fermentative substrates (e.g., energy crops, grass silage) and the digestate is returned to the peatlands. However, drained organic soils are considered as hot spots for nitrous oxide (N2O) emissions and organic fertilization is additionally known to increase N2O emissions from managed grasslands. Our study addressed the questions (a) to what extent biogas digestate and cattle slurry application increase N2O and methane (CH4) fluxes as well as the mineral nitrogen use efficiency (NUEmin) and grass yield, and (b) how different soil organic matter contents (SOMs) and nitrogen contents promote the production of N2O. In addition NH3 volatilization was determined at one application event to obtain first clues with respect to the effects of soil and fertilizer types. The study was conducted at two sites within a grassland parcel, which differed in their soil organic carbon (SOC) and N contents. At each site (named Corg-medium and Corg-high) three plots were established: one was fertilized five times with biogas digestate, one with cattle slurry, and the third served as control plot. On each plot, fluxes of N2O and CH4 were measured on three replicates over 2 years using the closed chamber method. For NH3 measurements we used the calibrated dynamic chamber method. On an annual basis, the application of biogas digestate significantly enhanced the N2O fluxes compared to the application of cattle slurry and additionally increased the plant N-uptake and NUEmin. Furthermore, N2O fluxes from the Corg-high treatments significantly exceeded N2O fluxes from the Corg-medium treatments. Annual cumulative emissions ranged from 0.91 ± 0.49 to 3.14 ± 0.91 kg N ha−1 yr−1. Significantly different CH4 fluxes between the investigated treatments or the different soil types were not observed. Cumulative annual CH4 exchange rates varied between −0.21 ± 0.19 and −1.06 ± 0.46 kg C ha−1 yr−1. Significantly higher NH3 losses, NUEmin and grass yields from treatments fertilized with biogas digestate compared to those fertilized with cattle slurry were observed. The total NH3 losses following the splash plate application were 18.17 kg N ha−1 for the digestate treatments and 3.48 kg N ha−1 for the slurry treatments (36 and 15% of applied NH4+–N). The observed linear increase of 16 days' cumulative N2O–N exchange or annual N2O emissions, with mean groundwater level and ammonium application rate, reveals the importance of site-adapted N fertilization and the avoidance of N surpluses in Corg-rich grasslands.

scholarly journals Effect of Nitrification Inhibitors on N2O Emissions after Cattle Slurry Application

Agronomy ◽  
2020 ◽  
Vol 10 (8) ◽  
pp. 1174 ◽  
Author(s):  
Christina Herr ◽  
Thomas Mannheim ◽  
Torsten Müller ◽  
Reiner Ruser
Keyword(s):  
Management Practice ◽  
Ghg Emissions ◽  
N2o Emissions ◽  
Nitrification Inhibitors ◽  
Ghg Emission ◽  
Cattle Slurry ◽  
Closed Chamber ◽  
Study Region ◽  
Silage Maize ◽  
N2o Fluxes

Cattle slurry injection (INJ) has shown to be an efficient measure to reduce ammonia (NH3) losses from soils but it might also significantly increase nitrous oxide (N2O) emissions, which can dominate the total greenhouse gas (GHG) release in silage maize production (Zea mays L.). Nitrification inhibitors (NIs) are known for their potential to mitigate N2O. Therefore, we tested the effect of NIs added to cattle slurry before INJ on N2O fluxes from a Haplic Luvisol under silage maize in southwest Germany. We determined N2O fluxes at least weekly, with the closed chamber method over two full years. NIs differ in their chemical and physical behavior and we therefore tested a range of commercially available NIs: 3,4-dimethylpyrazole phosphate, 3,4-dimethylpyrazol succinic acid, a mixture of both, nitrapyrin, dicyandiamide, and 1,2,4 triazol and 3-methylpyrazol. Although not significant, INJ treatments with NI showed lower mean annual N2O emissions than the INJ treatment without NI in the 1st year. The emission reduction by NI of 46% in the 2nd year was statistically significant. In both years, we did not find any difference in N2O release, crop yield, or nitrogen removal between the different NI treatments. In the 1st year, which was extraordinary dry and warm, emission factors (EFs) for all INJ treatments were 4 to 8-fold higher than default EF from the IPCC. Even in the 2nd year, only three NI treatments reached EFs within the range provided by the IPCC. Direct N2O accounted for between 81 and 91% of the total GHG emission. Area- and yield-related GHG emission of the broadcast application with subsequent incorporation was in both years in the statistical class with lowest emission. In contrast, INJ with NIs showed similar GHG emissions in only one year, and consequently, incorporation was found to be the optimum management practice for livestock farmers in our study region.

scholarly journals High-Temperature Hay Biochar Application into Soil Increases N2O Fluxes

Agronomy ◽  
2020 ◽  
Vol 10 (1) ◽  
pp. 109 ◽  
Author(s):  
Jordi Escuer-Gatius ◽  
Merrit Shanskiy ◽  
Kaido Soosaar ◽  
Alar Astover ◽  
Henn Raave
Keyword(s):  
High Temperature ◽  
Soil Amendment ◽  
Organic Fertilizer ◽  
Organic Fertilizers ◽  
Soil Conditions ◽  
N2o Emissions ◽  
Cattle Slurry ◽  
N Losses ◽  
Production Temperature ◽  
N2o Fluxes

Biochar has been proposed as an amendment that can improve soil conditions, increase harvest yield, and reduce N losses through NO3− leaching and N2O emissions. We conducted an experiment to test the hay biochar mitigation effect on N2O emissions depending on its production temperature. The pot experiment consisted of the soil amendment with three different production temperature biochars (300 °C, 550 °C, 850 °C) alone and in combination with three different organic fertilizers (cattle slurry, slurry digestate, vinasse), in growth chamber conditions. The effects of biochar and fertilizer were both significant, but the interaction biochar:fertilizer was not. The amendment with the three fertilizer types and with the highest production temperature biochar resulted in significantly higher cumulative N2O fluxes. Biochar did not show a mitigation effect on N2O emissions when applied with organic fertilizer. Cumulative emissions were higher with biochar addition, with increasing emissions for increasing biochar production temperature. Our results support the idea that biochar cannot be considered as a universal tool for the reduction of N2O emissions.

scholarly journals Review of key causes and sources for N<sub>2</sub>O emissions and NO<sub>3</sub>-leaching from organic arable crop rotations

2018 ◽  
Author(s):  
Sissel Hansen ◽  
Randi Berland Frøseth ◽  
Maria Stenberg ◽  
Jarosław Stalenga ◽  
Jørgen E. Olesen ◽  
...  
Keyword(s):  
Organic Matter ◽  
Nitrate Leaching ◽  
Organic Production ◽  
Crop Rotations ◽  
Organic Fertilizers ◽  
N2o Emissions ◽  
Catch Crops ◽  
Arable Crop ◽  
N2o Fluxes ◽  
The Impact

Abstract. The emissions of nitrous oxide (N2O) and leaching of nitrate (NO3) have considerable negative impacts on climate and the environment. Although these environmental burdens are on average less per unit area in organic than in non-organic production, they are not smaller per unit of product. If organic farming is to maintain its goal of being an environmentally friendly production system, these emissions should be mitigated. We discuss the impact of possible triggers within organic arable farming practice for the risk of N2O emissions and NO3 leaching under European climatic conditions, and possible strategies to reduce these. Organic arable crop rotations can be characterised as diverse with frequent use of legumes, intercropping and organic fertilizers. The soil organic matter content and share of active organic matter, microbial and faunal activity are higher, soil structure better and yields lower, than in non-organic, arable crop rotations. Soil mineral nitrogen (SMN), N2O emissions and NO3 leaching are low under growing crops, but there is high potential for SMN accumulation and losses after crop termination or crop harvest. The risk for high N2O fluxes is increased when large amounts of herbage or organic fertilizers with readily available nitrogen (N) and carbon are incorporated into the soil or left on the surface. Freezing/thawing, drying/rewetting, compacted and/or wet soil and mixing with rotary harrow further enhance the risk for high N2O fluxes. These complex soil N dynamics mask the correlation between total N-input and N2O emissions from organic arable crop rotations. Incorporation of N rich plant residues or mechanical weeding followed by bare fallow increases the risk of nitrate leaching. In contrast, strategic use of deep-rooted crops with long growing seasons in the rotation reduces nitrate leaching risk. Reduced tillage can reduce N leaching if yields are maintained. Targeted treatment and use of herbage from green manures, crop residues and catch crops will increase N efficiency and reduce N2O emissions and NO3 leaching. Continued regular use of catch crops has the potential to reduce NO3 leaching but may enhance N2O emissions. A mixture of legumes and non-legumes (for instance grasses or cereals) are as efficient a catch crop as monocultures of non-legume species.

scholarly journals Nitrous oxide fluxes from tropical peat with different disturbance history and management

2011 ◽  
Vol 8 (3) ◽  
pp. 5423-5450 ◽  
Author(s):  
J. Jauhiainen ◽  
H. Silvennoinen ◽  
R. Hämäläinen ◽  
K. Kusin ◽  
S. Limin ◽  
...  
Keyword(s):  
Nitrous Oxide ◽  
Greenhouse Gas ◽  
N2o Emissions ◽  
Monitoring Methods ◽  
N2o Flux ◽  
Swamp Forest ◽  
Closed Chamber ◽  
Tropical Peat ◽  
C Stocks ◽  
N2o Fluxes

Abstract. Tropical peatlands are one of the most important terrestrial ecosystems in terms of C stocks, and greenhouse gas emissions following disturbances such as deforestation, drainage or wildfire. Nitrous oxide dynamics in tropical peat systems is still poorly known. We quantified in situ N2O fluxes using closed chamber methods and compared them with CO2 and CH4 fluxes at sites representing differing land uses and land use change intensities, i.e. non-drained and drained selectively logged peat swamp forest, clear-felled drained recovering forest, deforested drained and burned peat, and agriculture on peat. The mean N2O flux rates (N2O-N ± SD, mg m−2 h−1) varied as follows: drained forest (0.112 ± 0.293) > agricultural peat in Kalampangan site (0.012 ± 0.026) > drained burned peat (0.011 ± 0.018) > agricultural peat in Marang site (0.0072 ± 0.028) > nondrained forest (0.0025 ± 0.053) > clear-felled drained recovering forest (0.0022 ± 0.021). Most N2O fluxes were < 0.05 mg N2O-N m−2 h−1 efflux, but some modest peat N2O influx readings were also detected. Many very high flux rates (deviating markedly from the majority of observations) occurred both spatially and over time, and further studies using continuous flux monitoring methods are needed to better understand the contribution of these to cumulative emissions. The widest N2O flux amplitude was detected in the drained forest with moderately drained peat (max. 2.312 and min. −0.043 mg N2O-N m−2 h−1. At the other sites the flux amplitude remained about 10 × smaller. Annual cumulative peat surface N2O emissions expressed as CO2 equivalents as a percentage of the total greenhouse gas (N2O, CO2 and CH4) emissions was at the highest 9.2 %, but typically ~1 %.

scholarly journals Nitrous oxide emission hotspots from organic soils in Europe

2014 ◽  
Vol 11 (6) ◽  
pp. 9135-9182
Author(s):  
T. Leppelt ◽  
R. Dechow ◽  
S. Gebbert ◽  
A. Freibauer ◽  
A. Lohila ◽  
...  
Keyword(s):  
Nitrous Oxide ◽  
Greenhouse Gas ◽  
Ph Value ◽  
A Priori ◽  
Emission Factors ◽  
Organic Soils ◽  
N2o Emissions ◽  
The European Union ◽  
Study Results ◽  
N2o Fluxes

Abstract. Organic soils are a main source of direct nitrous oxide (N2O) emissions, an important greenhouse gas (GHG). Observed N2O emissions from organic soils are highly variable in space and time which causes high uncertainties in national emission inventories. Those uncertainties could be reduced when relating the upscaling process to a priori identified key drivers by using available N2O observations from plot scale in empirical approaches. We used the empirical fuzzy modelling approach MODE to identify main drivers for N2O and utilize them to predict the spatial emission pattern of European organic soils. We conducted a meta study with a total amount of 659 annual N2O measurements which was used to derive separate models for different land use types. We applied our models to available, spatial explicit input driver maps to upscale N2O emissions on European level and compared the inventory with recently published IPCC emission factors. The final statistical models explained up to 60% of the N2O variance. Our study results showed that cropland and grasslands emitted the highest N2O fluxes 0.98 ± 1.08 and 0.58 ± 1.03 g N2O-N m−2 a−1, respectively. High fluxes from cropland sites were mainly controlled by low soil pH-value and deep drained groundwater tables. Grassland hotspot emissions were strongly related to high amount of N-fertilizer inputs and warmer winter temperatures. In contrast N2O fluxes from natural peatlands were predominantly low (0.07±0.27 g N2O-N m−2 a−1) and we found no relationship with the tested drivers. The total inventory for direct N2O emissions from organic soils in Europe amount up to 149.5 Gg N2O-N a−1, which included also fluxes from forest and peat extraction sites and exceeds the inventory calculated by IPCC emission factors of 87.4 Gg N2O-N a−1. N2O emissions from organic soils represent up to 13% of total European N2O emissions reported in the European Union (EU) greenhouse gas inventory of 2011 from only 7% of the EU area. Thereby the model demonstrated that with up to 85% the major part of the inventory is induced by anthropogenic management, which shows the significant reduction potential by rewetting and extensivation of agricultural used peat soils.

scholarly journals Application of organic fertilizers alter the physical and biogeochemical properties of agricultural topsoil and subsoil

2021 ◽  
Author(s):  
Anke Neumeier ◽  
Julien Guigue ◽  
Yaser Ostovari ◽  
Andreas Muskolus ◽  
Henk Martens ◽  
...  
Keyword(s):  
Organic Carbon ◽  
Soil Fertility ◽  
Organic Amendments ◽  
Mineral Fertilizer ◽  
Organic Fertilizers ◽  
Mineral Fertilizers ◽  
Carbon And Nitrogen ◽  
Biogas Digestate ◽  
Nitrogen Contents ◽  
Soc Stocks

&lt;p&gt;Sustainable agricultural practices aim to ensure the rebuilt of soil organic carbon (SOC) stocks and to sustain soil fertility. One of the levers is the use of carbon and nutrient inputs in the form of organic amendments, such as farmyard manure, slurry and biogas digestate. These organic fertilizers represent a promising alternative to the mineral fertilizers, which are mainly made from non-renewable resources. The use mineral fertilizers is indeed associated with an excessive use of natural resources and a loss of biodiversity. The effect of organic amendments compared with traditional mineral fertilizers on SOC stocks and soil fertility are uncertain in the longer-term. We aimed at investigating the effects of mineral and organic fertilizers (i.e., manure, pig slurry and biogas digestate) on topsoil and subsoil biogeochemistry, after eight years of application. For this purpose, we sampled soil cores down to a depth of one meter in a randomized field experiment in Germany, running since 2011. A full-profile assessment of the carbon and nitrogen distribution, stability and bioavailability was achieved using a combination of classical bulk physico-chemical analyses (e.g., SOC and nitrogen contents, texture, pH, bulk density) and state-of-the-art imaging techniques. Selected samples were analysed for aggregate size distribution, as well as organic carbon and nitrogen contents and allocation within these aggregates. Further, undisturbed core-samples were scanned using a hyperspectral camera in the Vis-NIR range to reveal hotspots of carbon storage at the soil profile scale. Soil carbon distribution was predicted as a function of spectral response, using a variety of machine learning approaches. The application of organic fertilizers (whatever their nature) resulted in higher SOC contents in the first 10 cm, as compared to the control and the mineral fertilizer treatments. The SOC stocks were + 21-33 % higher in the soil treated with organic fertilizers as compared to the control treatment. The application of mineral fertilizer or digestate, as compared to the control, resulted in higher relative amount of microaggregates (versus macroaggregates) (+ 19-40 %) in the soil down to 80 cm. These results will provide essential information to develop management strategies that increase nutrient recycling as well as SOC stocks.&lt;/p&gt;

scholarly journals Nitrous Oxide Emission from Organic Fertilizer and Controlled Release Fertilizer in Tea Fields

2017 ◽  
Author(s):  
Meihua Deng ◽  
Mudan Hou ◽  
Naoko Ohkama-Ohtsu ◽  
Tadashi Yokoyama ◽  
Haruo Tanaka ◽  
...  
Keyword(s):  
Nitrous Oxide ◽  
Controlled Release ◽  
Green Tea ◽  
Organic Fertilizer ◽  
Organic Fertilizers ◽  
Chicken Manure ◽  
Fertilizer Treatment ◽  
N2o Emissions ◽  
Closed Chamber ◽  
Controlled Release Fertilizers

A field experiment was conducted for 2 years in Green Tea Laboratory of Saitama Prefectural Agriculture and Forestry Research Center, Iruma, Saitama, Japan from March 2014 to December 2015. Controlled release fertilizers (CRF) or organic fertilizers (ORG) which is the mixture of chicken manure and oil cakewere applied with the amount of 450 kg N ha-1 yr-1 in 2014 and 397 kg N ha-1 yr-1 in 2015. Nitrous oxide (N2O) emissionsfrom soil in green tea fields were measured by closed chamber method. The results showed that CRF has significantly lower N2O compared to ORG. The cumulative N2O emissions from CRF accounted for 51% of N2O emissions from ORG fields and 138% of control with no fertilizer treatment. The N2O flux from the row was higher than that of under the canopy, since fertilizer were applied on the row. However the total emission from the area between the rows was lower than that under the canopy because of the area ratio of row and canopy was 1:5.

scholarly journals Field Application of Organic Fertilizers Triggers N2O Emissions From the Soil N Pool as Indicated by 15N-Labeled Digestates

2021 ◽  
Vol 4 ◽  
Author(s):  
Franziska Häfner ◽  
Reiner Ruser ◽  
Ingrid Claß-Mahler ◽  
Kurt Möller
Keyword(s):  
Weather Conditions ◽  
Field Application ◽  
Organic Fertilizers ◽  
Organic N ◽  
N2o Emissions ◽  
Soil N ◽  
Closed Chamber ◽  
Total N ◽  
N Sources ◽  
Ammonium N

Anaerobic digestion (AD) can generate biogas while simultaneously producing digestate which can be used as fertilizer. Feedstocks used for AD influence digestate composition, which in turn may affect carbon (C) and nitrogen (N) turn-over in soils and subsequently influence nitrous oxide (N2O) emissions after soil application. Assessment of greenhouse gas emissions from digestates can help to evaluate the overall sustainability of an agricultural production system. The objective of this study was therefore to evaluate and understand the effect of differences in digestate composition on in situ N2O emissions within the 1st weeks after application of seven digestates. The digestates were derived from different feedstocks and 15N-labeled, either in total N or only in ammonium-N. Therefore, the experimental design enabled us to differentiate between potential N2O-N sources (i.e., digestate N or soil N). Furthermore, it allowed to distinguish to some extent between organic-N and ammonium-N as potential N sources for denitrification. Digestates were homogeneously incorporated into the upper 5 cm of microplots in an arable Haplic Luvisol in South Germany at a rate of 170 kg N ha−1. After application, N2O fluxes were measured for ~60 days (May-July) using the closed chamber method in 2 experimental years. Mainly due to higher precipitations in the 1st year, cumulative N2O emissions were higher (312–1,580 g N2O-N ha−1) compared to the emissions (133–690 g N2O-N ha−1) in the 2nd year. Between 16–33% (1st year) and 17–38% (2nd year) of N2O emissions originated from digestate N, indicating that digestate application triggered N2O production and release mainly from soil N. This effect was strongest immediately after digestate application. It was concluded that the first (short term) peak in N2O emissions after digestate application is largely related to denitrification of soil-N. However, the experimental setup does not allow to differentiate between the different denitrification pathways. Weather conditions showed a substantial effect on N2O emissions, where the correlation between N2O and CO2 flux rates hinted on denitrification as main N2O source. The effect of digestate composition, particularly organic N from the digestate, on soil N2O emissions seems to be of minor relevance.

scholarly journals Nitrous oxide emission budgets and land-use-driven hotspots for organic soils in Europe

2014 ◽  
Vol 11 (23) ◽  
pp. 6595-6612 ◽  
Author(s):  
T. Leppelt ◽  
R. Dechow ◽  
S. Gebbert ◽  
A. Freibauer ◽  
A. Lohila ◽  
...  
Keyword(s):  
Land Use ◽  
Nitrous Oxide ◽  
Greenhouse Gas ◽  
Ph Value ◽  
Emission Factors ◽  
Organic Soils ◽  
N2o Emissions ◽  
The European Union ◽  
Study Results ◽  
N2o Fluxes

Abstract. Organic soils are a main source of direct emissions of nitrous oxide (N2O), an important greenhouse gas (GHG). Observed N2O emissions from organic soils are highly variable in space and time, which causes high uncertainties in national emission inventories. Those uncertainties could be reduced when relating the upscaling process to a priori-identified key drivers by using available N2O observations from plot scale in empirical approaches. We used the empirical fuzzy modelling approach MODE to identify main drivers for N2O and utilize them to predict the spatial emission pattern of European organic soils. We conducted a meta-study with a total amount of 659 annual N2O measurements, which was used to derive separate models for different land use types. We applied our models to available, spatially explicit input driver maps to upscale N2O emissions at European level and compared the inventory with recently published IPCC emission factors. The final statistical models explained up to 60% of the N2O variance. Our study results showed that cropland and grasslands emitted the highest N2O fluxes 0.98 ± 1.08 and 0.58 ± 1.03 g N2O-N m−2 a−1, respectively. High fluxes from cropland sites were mainly controlled by low soil pH value and deep-drained groundwater tables. Grassland hotspot emissions were strongly related to high amount of N-fertilizer inputs and warmer winter temperatures. In contrast, N2O fluxes from natural peatlands were predominantly low (0.07 ± 0.27 g N2O-N m−2 a−1) and we found no relationship with the tested drivers. The total inventory for direct N2O emissions from organic soils in Europe amount up to 149.5 Gg N2O-N a−1, which also included fluxes from forest and peat extraction sites and exceeds the inventory calculated by IPCC emission factors of 87.4 Gg N2O-N a−1. N2O emissions from organic soils represent up to 13% of total European N2O emissions reported in the European Union (EU) greenhouse gas inventory of 2011 from only 7% of the EU area. Thereby the model demonstrated that the major part (85%) of the inventory is induced by anthropogenic management, which shows the significant reduction potential by rewetting and extensification of agriculturally used peat soils.

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