Suchergebnisse

Agricultural management practices play an important role in greenhouse gases (GHG) emissions due to their impact on the soil microenvironment. In this study, two experiments were performed to investigate the influence of tillage and N fertilization on GHG production at the macroaggregate scale. In the first experiment, soil macroaggregates collected from a field experiment comparing various soil management systems (CT, conventional tillage; NT, no-tillage) and N fertilization types (a control treatment without N and mineral N and organic N with pig slurry treatments both at 150kgNha-1) were incubated for 35 days. Methane (CH4), carbon dioxide (CO2) and nitrous oxide (N2O) production was quantified at regular time intervals by gas chromatography. In the second experiment, the effects of fertilization type and soil moisture on the relative importance of nitrification and denitrification processes in N2O emission from soil macroaggregates were quantified. Nitrate ammonium, macroaggregate-C concentration, macroaggregate water-stability, microbial biomass-C and N (MBC and MBN, respectively) and water-soluble C (WSC) were determined. While NT macroaggregates showed methanotrophic activity, CT macroaggregates acted as net CH4 producers. However, no significant differences were found between tillage systems on the fluxes and cumulative emissions of CO2 and N2O. Greatest cumulative CO2 emissions, macroaggregate-C concentration and WSC were found in the organic N fertilization treatment and the lowest in the control treatment. Moreover, a tillage and N fertilization interactive effect was found in macroaggregate CO2 production: while the different types of N fertilizers had no effects on the emission of CO2 in the NT macroaggregates, a greater CO2 production in the CT macroaggregates was observed for the organic fertilization treatment compared with the mineral and control treatments. The highest N2O losses due to nitrification were found in the mineral N treatment while denitrification was the main factor affecting N2O losses in the organic N treatment. Our results suggest that agricultural management practices such as tillage and N fertilization regulate GHG production in macroaggregates through changes in the proportion of C and N substrates and in microbial activity. ; This research was supported by the Comisión Interministerial de Ciencia y Tecnología of Spain (grants AGL 2007-66320-C02-01 and AGL 2010-22050-C03-01/02) and by the Aragon Government and La Caixa (grant GA-LC-050/2011).

Workplace safety is a concern for both scholars and practitioners alike because accidents and injuries can result in time away from work and lost organizational resources. This study focuses on how one type of post-incident discussion can be effectively used to promote positive safety norms. It adds to the growing body of research on after action review meetings, one type of post-incident discussion intervention commonly used in high reliability organizations to increase future workplace safety behaviors. This study also extends the sensemaking and high reliability literatures by examining a three-way interaction between perceived frequency of after action review meetings, ambiguity reduction and psychological safety. Survey data were obtained from 330 firefighters. Results from the three-way interaction showed that safety norms were highest when perceived after action review frequency, ambiguity reduction and psychological safety were simultaneously high, and safety norms were lowest when perceived after action review frequency, ambiguity reduction and psychological safety were simultaneously low. By examining both the perceived quantity and quality of after action review meetings, this study provides insight into which after action review facilitation objectives are most likely to increase positive safety norms and ultimately create a shared understanding of how to behave safely in future workplace events in high reliability organizational contexts.

49 Pags., 6 Tabls., 4 Figs. The definitive version is available at: http://www.sciencedirect.com/science/journal/00380717 ; Agricultural management practices play an important role in greenhouse gases (GHG) emissions due to their impact on the soil microenvironment. In this study, two experiments were performed to investigate the influence of tillage and N fertilization on GHG production at the macroaggregate scale. In the first experiment, soil macroaggregates collected from a field experiment comparing various soil management systems (CT, conventional tillage; NT, no-tillage) and N fertilization types (a control treatment without N and mineral N and organic N with pig slurry treatments both at 150kgNha-1) were incubated for 35 days. Methane (CH4), carbon dioxide (CO2) and nitrous oxide (N2O) production was quantified at regular time intervals by gas chromatography. In the second experiment, the effects of fertilization type and soil moisture on the relative importance of nitrification and denitrification processes in N2O emission from soil macroaggregates were quantified. Nitrate ammonium, macroaggregate-C concentration, macroaggregate water-stability, microbial biomass-C and N (MBC and MBN, respectively) and water-soluble C (WSC) were determined. While NT macroaggregates showed methanotrophic activity, CT macroaggregates acted as net CH4 producers. However, no significant differences were found between tillage systems on the fluxes and cumulative emissions of CO2 and N2O. Greatest cumulative CO2 emissions, macroaggregate-C concentration and WSC were found in the organic N fertilization treatment and the lowest in the control treatment. Moreover, a tillage and N fertilization interactive effect was found in macroaggregate CO2 production: while the different types of N fertilizers had no effects on the emission of CO2 in the NT macroaggregates, a greater CO2 production in the CT macroaggregates was observed for the organic fertilization treatment compared with the mineral and control treatments. The highest N2O losses due to nitrification were found in the mineral N treatment while denitrification was the main factor affecting N2O losses in the organic N treatment. Our results suggest that agricultural management practices such as tillage and N fertilization regulate GHG production in macroaggregates through changes in the proportion of C and N substrates and in microbial activity. ; D. Plaza-Bonilla was awarded an FPU fellowship by the Spanish Ministry of Education. This research was supported by the Comisión Interministerial de Ciencia y Tecnología of Spain (grants AGL 2007-66320-C02-01 and AGL 2010-22050-C03-01/02) and by the Aragon Government and La Caixa (grant GA-LC-050/2011). ; Peer Reviewed

There is a strong need to identify the combination of tillage and N fertilization practices that reduce the amount of nitrous oxide (N2O) emissions while maintaining crop productivity in dryland Mediterranean areas. We measured the fluxes of N2O in two field experiments with 3 and 15 years since their establishment. In the long-term experiment, two types of tillage (NT, no-tillage, and CT, conventional intensive tillage) and three mineral N fertilization rates (0, 60 and 120 kg N ha−1) were compared. In the short-term experiment, the same tillage systems (CT and NT) and three N fertilization doses (0, 75 and 150 kg N ha−1) and two types of fertilizers (mineral N and organic N with pig slurry) were compared. N2O emissions, water-filled pore space, soil mineral N content, grain yields, N-biomass inputs and soil total nitrogen (STN) stocks were quantified and the N2O yield-scaled ratio as kg of CO2 equivalents per kg of grain produced was calculated. In both experiments tillage treatments significantly affected the dynamics of N2O fluxes. Cumulative losses of N as N2O were similar between tillage treatments in the long-term field experiment. Contrarily, although not significant, cumulative N losses were about 35% greater under NT than CT in the short-term experiment. NT significantly increased the production of grain and the inputs of N to the soil as above-ground biomass in both experiments. Averaged across fertilizer treatments, CT emitted 0.362 and 0.104 kg CO2 equiv. kg grain−1 in the long-term and the short-term experiment, respectively, significantly more than NT that emitted 0.033 and 0.056 kg CO2 equiv. kg grain−1, respectively. Nitrogen fertilization rates did not affect the average N2O fluxes or the total N losses during the period of gas measurement in the long-term experiment. Contrarily, in the short-term experiment, N2O emissions increased with application rate for both mineral and organic fertilizers. The use of pig slurry increased grain production when compared with the mineral N treatment, thus reducing the yield-scaled emissions of N2O by 44%. Our results showed that in rainfed Mediterranean agroecosystems, the use of NT and pig slurry are effective means of yield-scaled N2O emissions reduction. ; This research was supported by the Comisión Interministerial de Ciencia y Tecnología of Spain (grants AGL 2007-66320-C02-01 and AGL 2010-22050-C03-01/02), the Aragon Government and La Caixa (grant GA-LC-050/2011), the Department of Agriculture of the Catalonia Government (grant 2012 AGEC 00012) and the European Union (FEDER funds).

The fiscal reviewer as an important part in the proper development in the country must rethink its professional work in terms of responsibility to society and its problems. Corruption as a central issue in the Colombian national scene raises several questions, regarding the duty of the fiscal reviewer and how it could play a much more important role in regard to the oversight of the work done in the institutions that manage resources of the public treasury. This article proposes an interesting proposal to strengthen and optimize the governmental control entities with a view to reducing and not ending the problem of corruption in Colombia, besides making a tour through the history of the profession, the main laws that regulate it, the most notorious cases of corruption in Colombia and the panorama that the new international financial information standards pose for the profession. The methodology used for the realization of this article is the thorough and detailed bibliographic review of the current regulations in relation to the fiscal review, as well as the information resulting from the consultation on the most important cases of corruption in the Colombian sphere and between the main results stand out, among others the duty of the fiscal reviewer in the social field, the challenges posed to professionals by the entry into force of international IFRS standards, in addition to highlighting the ineffectiveness of the control exercised by the entities Government in Colombia ; La revisoría fiscal como parte importante en el correcto desarrollo en el país debe replantear su quehacer profesional en cuanto a la responsabilidad con la sociedad y sus problemáticas. La corrupción como tema central en el panorama nacional colombiano plantea diversas interrogantes, frente al deber ser de la revisoría fiscal y el como podría jugar un papel mucho mas importante en lo que respecta a la veeduría de la labor realizada en las instituciones que manejan recursos del erario publico. El presente articulo plantea una interesante propuesta para fortalecer y optimizar los entes de control gubernamentales con miras a reducir y porque no acabar la problemática de la corrupción en Colombia, además de hacer un recorrido por la historia de la profesión, las principales leyes que la regulan, los casos más sonados de corrupción en Colombia y el panorama que plantea para la profesión las nuevas normas internacionales de información financiera. ; A revisão fiscalcomo parte importante no desenvolvimento adequado no país deve repensar seu trabalho profissional em termos de responsabilidade para a sociedade e seus problemas. A corrupção como tópico central na cena nacional colombiana levanta várias perguntas, em relação ao dever da revisão fiscal e como poderia desempenhar um papel muito mais importante em relação à supervisão do trabalho realizado em instituições que gerenciam recursos da tesouraria pública. Este artigo propõe uma proposta interessante para fortalecer e otimizar as entidades governamentais de controle com vistas a reduzir e porque não, acabar com o problema da corrupção na Colômbia, além de fazer um percorrido pela história da profissão, as principais leis que a regulamenta , os casos mais notórios de corrupção na Colômbia e o panorama que planteia para á profissão, as novas normas internacionais de informação financeira. A metodologia utilizada para a realização deste artigo é a revisão bibliográfica completa e detalhada da regulamentação atual em relação à revisão fiscal, bem como a informação resultante da consulta sobre os casos mais importantes de corrupção na esfera colombiana e entre os principais resultados destacam, entre outros, o dever da revisão fiscal no campo social, os desafios colocados aos profissionais pela entrada em vigor das normas internacionais NIIF, além de destacar a ineficácia do controle exercido pelas entidades governamentais na Colômbia.

The fiscal reviewer as an important part in the proper development in the country must rethink its professional work in terms of responsibility to society and its problems. Corruption as a central issue in the Colombian national scene raises several questions, regarding the duty of the fiscal reviewer and how it could play a much more important role in regard to the oversight of the work done in the institutions that manage resources of the public treasury. This article proposes an interesting proposal to strengthen and optimize the governmental control entities with a view to reducing and not ending the problem of corruption in Colombia, besides making a tour through the history of the profession, the main laws that regulate it, the most notorious cases of corruption in Colombia and the panorama that the new international financial information standards pose for the profession. The methodology used for the realization of this article is the thorough and detailed bibliographic review of the current regulations in relation to the fiscal review, as well as the information resulting from the consultation on the most important cases of corruption in the Colombian sphere and between the main results stand out, among others the duty of the fiscal reviewer in the social field, the challenges posed to professionals by the entry into force of international IFRS standards, in addition to highlighting the ineffectiveness of the control exercised by the entities Government in Colombia ; La revisoría fiscal como parte importante en el correcto desarrollo en el país debe replantear su quehacer profesional en cuanto a la responsabilidad con la sociedad y sus problemáticas. La corrupción como tema central en el panorama nacional colombiano plantea diversas interrogantes, frente al deber ser de la revisoría fiscal y el como podría jugar un papel mucho mas importante en lo que respecta a la veeduría de la labor realizada en las instituciones que manejan recursos del erario publico. El presente articulo plantea una interesante propuesta para fortalecer y optimizar los entes de control gubernamentales con miras a reducir y porque no acabar la problemática de la corrupción en Colombia, además de hacer un recorrido por la historia de la profesión, las principales leyes que la regulan, los casos más sonados de corrupción en Colombia y el panorama que plantea para la profesión las nuevas normas internacionales de información financiera. ; A revisão fiscalcomo parte importante no desenvolvimento adequado no país deve repensar seu trabalho profissional em termos de responsabilidade para a sociedade e seus problemas. A corrupção como tópico central na cena nacional colombiana levanta várias perguntas, em relação ao dever da revisão fiscal e como poderia desempenhar um papel muito mais importante em relação à supervisão do trabalho realizado em instituições que gerenciam recursos da tesouraria pública. Este artigo propõe uma proposta interessante para fortalecer e otimizar as entidades governamentais de controle com vistas a reduzir e porque não, acabar com o problema da corrupção na Colômbia, além de fazer um percorrido pela história da profissão, as principais leis que a regulamenta , os casos mais notórios de corrupção na Colômbia e o panorama que planteia para á profissão, as novas normas internacionais de informação financeira. A metodologia utilizada para a realização deste artigo é a revisão bibliográfica completa e detalhada da regulamentação atual em relação à revisão fiscal, bem como a informação resultante da consulta sobre os casos mais importantes de corrupção na esfera colombiana e entre os principais resultados destacam, entre outros, o dever da revisão fiscal no campo social, os desafios colocados aos profissionais pela entrada em vigor das normas internacionais NIIF, além de destacar a ineficácia do controle exercido pelas entidades governamentais na Colômbia.

This study focuses on the quantification of soil water storage and crop yield under different tillage systems in dryland semiarid Mediterranean conditions. Three long-term tillage experiments based on cereal production were initiated in 1987, 1990 and 1992, at three different locations in the Ebro river valley (NE Spain): El Canós, Selvanera and Agramunt, with an increasing degree of aridity. Different tillage intensities were compared in each experiment using different implements: no tillage (NT), minimum tillage (MT), chisel (Ch), subsoiler up to 25 cm depth (Sub-25) and up to 50 cm (Sub-50), and mouldboard plough (Mb). Soil water content (SWC) up to 100 cm, soil water storage (SWS), precipitation storage efficiency (PSE) and crop yield were quantified during 8 (El Canós) and 19 years (Selvanera and Agramunt). The use of MT (at Selvanera) and NT (at El Canós and Agramunt) led to the highest SWC after the storage period (i.e. from previous harvest to crop tillering), with a major role played by the storage of water at deep soil layers. At Agramunt, Mb presented the lowest SWS when compared to Ch, Sub-50 and NT, and, consequently, the lowest post-tillering evapotranspiration. On the contrary, no differences were found between tillage systems on SWS at El Canós or at Selvanera. Significant yield differences were found at Agramunt being: NT > Sub-50 > Ch = Mb. These differences were especially important in years with mean yield below 2000 kg ha-1, in which NT obtained the highest productions. At Selvanera yield was greater under conservation tillage (NT, MT) than under intensive tillage (Sub-50). Contrarily, no yield differences were found between tillage systems at El Canós, the site with the lowest water deficit, where crop residues were removed. A strong linear relationship was found between SWS and yield at Agramunt and Selvanera. At Agramunt the relationship presented a greater slope under Mb. In this site, in years with previous harvest-to-tillering SWS below 100 mm and with precipitation over 100 mm between tillering and anthesis, yields were, as an average, 1245 kg ha-1 higher than in standard years. This study demonstrates that under semiarid rainfed conditions, soil water storage increases with the use of conservation tillage systems, being amplified with the degree of aridity of the site. The relationship between water stored in the soil and crop yield and its reliability is site-specific. Once determined, it could be used to predict yield at the end of the vegetative phase of the crop to help take management decisions. ; This work was funded by the Comisión Interministerial de Ciencia y Tecnología (CICYT) of the Spanish Government, AGR91-312, AGF94-198, AGF98-261-C02,AGL2001- 2238-CO2-02, AGL2004-7763-C02-01, AGL2007- 66320-C02-01, AGL-2010-22050-C03-01, AGL2013-49062-C4-1projects. We also thank the farmers that collaborate in the development of the project, Josep Maria Besora, Josep Gabernet and Jaume Ramón. We especiallyacknowledge Jaume Gregori for hisinvolvement and technical support during the development of the experiments.

36 Pags.- 6 Figs. The definitive version is available at: http://www.sciencedirect.com/science/journal/03784290 ; This study focuses on the quantification of soil water storage and crop yield under different tillage systems in dryland semiarid Mediterranean conditions. Three long-term tillage experiments based on cereal production were initiated in 1987, 1990 and 1992, at three different locations in the Ebro river valley (NE Spain): El Canós, Selvanera and Agramunt, with an increasing degree of aridity. Different tillage intensities were compared in each experiment using different implements: no tillage (NT), minimum tillage (MT), chisel (Ch), subsoiler up to 25 cm depth (Sub-25) and up to 50 cm (Sub-50), and mouldboard plough (Mb). Soil water content (SWC) up to 100 cm, soil water storage (SWS), precipitation storage efficiency (PSE) and crop yield were quantified during 8 (El Canós) and 19 years (Selvanera and Agramunt). The use of MT (at Selvanera) and NT (at El Canós and Agramunt) led to the highest SWC after the storage period (i.e., from previous harvest to crop tillering), with a major role played by the storage of water at deep soil layers. At Agramunt, Mb presented the lowest SWS when compared to Ch, Sub-50 and NT, and, consequently, the lowest post-tillering evapotranspiration. On the contrary, no differences were found between tillage systems on SWS at El Canós or at Selvanera. Significant yield differences were found at Agramunt being: NT > Sub-50 > Ch = Mb. These differences were especially important in years with mean yield below 2000 kg ha−1, in which NT obtained the highest productions. At Selvanera yield was greater under conservation tillage (NT, MT) than under intensive tillage (Sub-50). Contrarily, no yield differences were found between tillage systems at El Canós, the site with the lowest water deficit, where crop residues were removed. A strong linear relationship was found between SWS and yield at Agramunt and Selvanera. At Agramunt the relationship presented a greater slope under Mb. In this site, in years with previous harvest-to-tillering SWS below 100 mm and with precipitation over 100 mm between tillering and anthesis, yields were, as an average, 1245 kg ha−1 higher than in standard years. This study demonstrates that under semiarid rainfed conditions, soil water storage increases with the use of conservation tillage systems, being amplified with the degree of aridity of the site. The relationship between water stored in the soil and crop yield and its reliability is site-specific. Once determined, it could be used to predict yield at the end of the vegetative phase of the crop to help take management decisions. ; This work was funded by the Comisión Interministerial de Ciencia y Tecnología (CICYT) of the Spanish Government, AGR91-312, AGF94-198, AGF98-261-C02, AGL2001-2238-CO2-02, AGL2004-7763-C02-01, AGL2007-66320-C02-01, AGL-2010-22050-C03-01, AGL2013-49062-C4-1 projects. ; Peer reviewed

39 Pags.- 4 Tabls.- 4 Figs. The defintive version is available at: http://www.sciencedirect.com/science/journal/01678809 ; There is a strong need to identify the combination of tillage and N fertilization practices that reduce the amount of nitrous oxide (N2O) emissions while maintaining crop productivity in dryland Mediterranean areas. We measured the fluxes of N2O in two field experiments with 3 and 15 years since their establishment. In the long-term experiment, two types of tillage (NT, no-tillage, and CT, conventional intensive tillage) and three mineral N fertilization rates (0, 60 and 120 kg N ha−1) were compared. In the short-term experiment, the same tillage systems (CT and NT) and three N fertilization doses (0, 75 and 150 kg N ha−1) and two types of fertilizers (mineral N and organic N with pig slurry) were compared. N2O emissions, water-filled pore space, soil mineral N content, grain yields, N-biomass inputs and soil total nitrogen (STN) stocks were quantified and the N2O yield-scaled ratio as kg of CO2 equivalents per kg of grain produced was calculated. In both experiments tillage treatments significantly affected the dynamics of N2O fluxes. Cumulative losses of N as N2O were similar between tillage treatments in the long-term field experiment. Contrarily, although not significant, cumulative N losses were about 35% greater under NT than CT in the short-term experiment. NT significantly increased the production of grain and the inputs of N to the soil as above-ground biomass in both experiments. Averaged across fertilizer treatments, CT emitted 0.362 and 0.104 kg CO2 equiv. kg grain−1 in the long-term and the short-term experiment, respectively, significantly more than NT that emitted 0.033 and 0.056 kg CO2 equiv. kg grain−1, respectively. Nitrogen fertilization rates did not affect the average N2O fluxes or the total N losses during the period of gas measurement in the long-term experiment. Contrarily, in the short-term experiment, N2O emissions increased with application rate for both mineral and organic fertilizers. The use of pig slurry increased grain production when compared with the mineral N treatment, thus reducing the yield-scaled emissions of N2O by 44%. Our results showed that in rainfed Mediterranean agroecosystems, the use of NT and pig slurry are effective means of yield-scaled N2O emissions reduction. ; D. Plaza-Bonilla was awarded with a FPU fellowship by the Spanish Ministry of Education. This research was supported by the Comisión Interministerial de Ciencia y Tecnología of Spain (grants AGL 2007-66320-C02-01 and AGL 2010-22050-C03-01/02), the Aragon Government and La Caixa (grant GA-LC-050/2011), the Department of Agriculture of the Catalonia Government (grant 2012 AGEC 00012) and the European Union (FEDER funds). ; Peer reviewed

Background and aims The effects of tillage and N fertilization on CO2 and CH4 emissions are a cause for concern worldwide. This paper quantifies these effects in a Mediterranean dryland area. Methods CO2 and CH4 fluxes were measured in two field experiments. A long-term experiment compared two types of tillage (NT, no-tillage, and CT, conventional intensive tillage) and three N fertilization rates (0, 60 and 120 kg N ha−1). A short-term experiment compared NT and CT, three N fertilization doses (0, 75 and 150 kg N ha−1) and two types of fertilizer (mineral N and organic N with pig slurry). Aboveground and root biomass C inputs, soil organic carbon stocks and grain yield were also quantified. Results The NT treatment showed a greater mean CO2 flux than the CT treatment in both experiments. In the long-term experiment CH4 oxidation was greater under NT, whereas in the short-term experiment it was greater under CT. The fertilization treatments also affected CO2 emissions in the short-term experiment, with the greatest fluxes when 75 and 150 kg organic N ha−1 was applied. Overall, the amount of CO2 emitted ranged between 0.47 and 6.0 kg CO2−equivalent kg grain−1. NT lowered yield-scaled emissions in both experiments, but these treatment effects were largely driven by an increase in grain yield. Conclusions In dryland Mediterranean agroecosystems the combination of NT and medium rates of either mineral or organic N fertilization can be an appropriate strategy for optimizing CO2 and CH4 emissions and grain yield. ; This research was supported by the Comisión Interministerial de Ciencia y Tecnología of Spain (grants AGL 2007-66320-C02-01 and AGL 2010-22050-C03-01/02), the Aragon Government and La Caixa (grant GA-LC-050/2011), the Department of Agriculture of the Government of Catalonia (grant 2012 AGEC 00012) and the European Union (FEDER funds).

The duration of soil organic carbon (SOC) sequestration in agricultural soils varies according to soil management, land-use history and soil and climate conditions. Despite several experiments have reported SOC sequestration with the adoption of no-tillage (NT) in Mediterranean dryland agroecosystems scarce information exists about the duration and magnitude of the sequestration process. For this reason, 20 years ago we established in northeast Spain a NT chronosequence experiment to evaluate SOC sequestration duration under Mediterranean dryland conditions. ; This work was supported by the Comisión Interministerial de Ciencia y Tecnología of Spain (Grants AGL2007-66320-CO2-02/AGR and AGL2010-22050-C03-01/02) and the European Union (FEDER funds). We acknowledge the Consejo Superior de Investigaciones Cientificas (CSIC) for the contract granted to Jorge Álvaro-Fuentes within the "Junta para la Ampliación de Estudios" (JAE-DOC) programme co-financed by the European Social Fund. Furthermore, Daniel Plaza-Bonilla was awarded with a FPU fellowship by the Spanish Ministry of Education.

20 Pags.- 7 Figs.- 5 Tabls. The definitive version is available at: http://link.springer.com/journal/11104 ; Background and aims The effects of tillage and N fertilization on CO2 and CH4 emissions are a cause for concern worldwide. This paper quantifies these effects in a Mediterranean dryland area. Methods CO2 and CH4 fluxes were measured in two field experiments. A long-term experiment compared two types of tillage (NT, no-tillage, and CT, conventional intensive tillage) and three N fertilization rates (0, 60 and 120 kg N ha−1). A short-term experiment compared NT and CT, three N fertilization doses (0, 75 and 150 kg N ha−1) and two types of fertilizer (mineral N and organic N with pig slurry). Aboveground and root biomass C inputs, soil organic carbon stocks and grain yield were also quantified. Results The NT treatment showed a greater mean CO2 flux than the CT treatment in both experiments. In the long-term experiment CH4 oxidation was greater under NT, whereas in the short-term experiment it was greater under CT. The fertilization treatments also affected CO2 emissions in the short-term experiment, with the greatest fluxes when 75 and 150 kg organic N ha−1 was applied. Overall, the amount of CO2 emitted ranged between 0.47 and 6.0 kg CO2−equivalent kg grain−1. NT lowered yield-scaled emissions in both experiments, but these treatment effects were largely driven by an increase in grain yield. Conclusions In dryland Mediterranean agroecosystems the combination of NT and medium rates of either mineral or organic N fertilization can be an appropriate strategy for optimizing CO2 and CH4 emissions and grain yield. ; D. Plaza-Bonilla was awarded an FPU fellowship by the Spanish Ministry of Education. This research was supported by the Comisión Interministerial de Ciencia y Tecnología of Spain (grants AGL 2007-66320-C02-01 and AGL 2010-22050-C03-01/02), the Aragon Government and La Caixa (grant GA-LC-050/2011), the Department of Agriculture of the Government of Catalonia (grant 2012 AGEC 00012) and the European Union (FEDER funds). ; Peer reviewed