No effect of cropping system on the greenhouse gas N2O

Organic farming is comparable to conventional in terms of field emissions of the strong greenhouse gas nitrous oxide (N2O). Our study points to the need for increased yields in organic farming as measure to reduced emissions per unit of produce

Ingen effekt af dyrkningssystem på drivhusgassen N2O

Økologisk jordbrug er sammenligneligt med det konventionelle, når det gælder udledning af den stærke drivhusgas lattergas (N2O) fra dyrkningsjorden. Vores undersøgelse viser, at økologisk jordbrug bør tilstræbe højere høstudbytter som et middel til at reducere N2O-udledningen per produceret enhed

Results on life cycle assessments to determine impacts of agronomic management choices in the Cauca and Honduras CSV

The intense management of the crops, that characterizes current agricultural cropping systems, has resulted in increased concentrations of greenhouse gases (GHGs) such as carbon dioxide (CO2), methane (CH4), and nitrous oxide (N2O). In this study, we used the field-scale agricultural assessment model - Cool Farm Tool (CFT), to model GHG emissions and uptake estimates (Hillier et al., 2011). This tool combines different algorithms that integrate climate, soil and crop data and presents outputs on carbon footprints in a format that is accessible to non-experts. Furthermore, the CFT provides the possibility to compare GHG emissions and uptake estimates from different production sites and systems. Finally, the tool CFT enables crop producers and stakeholders to take a more informed and holistic approach to environmental sustainability in the agricultural sector

Effects of organic matter input on soil microbial properties and crop yields in conventional and organic cropping systems

Unlike conventional cropping systems, which are characterised by targeted short-term fertility management, organic farming systems depend on long-term increase in soil fertility and promotion of soil biodiversity. This study sought to investigate long-term effects of organic matter inputs on various cropping systems in a 10-year-old experiment. Results show that in the long-term high C and N inputs enhance microbial activity. Microbial biomass N and the potential nitrification rate were higher in cropping systems based on green manure than in those reliant on inputs from animal manure and mineral fertilizer. Soil microbiological properties were affected by the individual crops in the rotation. The high microbial activity with increased organic matter inputs did not transform to enhanced crop productivity

Gender [im]balance in productive and reproductive labor among livestock producers in Colombia: Implications for climate change responses

Roles and responsibilities in livestock production and household maintenance are segregated along gender lines. Men’s and women’s participation in the livestock sector varies by tasks. Women combine livestock production, particularly, milk processing activities with the responsibility of household and care work. Men’s and women’s indirect contribution with regard to maintenance of the household and care provision to family members is also crucial for healthy and smooth functioning of livestock productive activities and therefore, must be accounted for in policy decisions, including those related to changing climate. As a response to climate change induced drought, men, and particularly women, are investing their labor in alternative sources of income to pay for water provision services to meet the water demands of their animals. For women who already face the double burden of productive and reproductive work, this coping mechanism may deepen their time poverty

How might the gender roles affect the implementation of a new water-saving technique for Colombian rice production? : Report of gender dimensions in Colombian rice production

Globally, rice cultivation is responsible for 10% of greenhouse gas emissions released by agricultural activities. To sustainably reduce the contribution of rice to greenhouse gas (GHG) emissions, it is important to pursue management and technological options that reduce emissions and improve farmer productivity, adaptation and resilience to climate change impacts. Alternate wetting and drying (AWD) is a water-saving technique that helps farmers adapt to less water availability. It reduces the amount of in-field gas emissions associated with rice production, and it may increase and/or maintain rice productivity levels. The International Center for Tropical Agriculture (CIAT) and partners are conducting several studies to evaluate the feasibility of implementing this technology in Colombia, a country that has committed to reducing economy-wide GHG emissions by 20% under the 2015 Paris Agreement and implementing adaptation plans by 2030. The sustainable implementation of AWD requires an understanding of the economic, climatic, political, agronomic and social considerations within which farmers operate. The literature shows how gender roles can influence the adoption of a technology or be affected by the introduction of a new technology. A baseline study was designed to answer the following questions: how might gender impact the adoption of AWD in Colombia? And how will the adoption of AWD affect the gender division of labor? A household survey with sex-disaggregated information in 609 households in five departments was conducted. The results suggest that women own rice assets and make decisions about production but are not recognized as rice producers. They do not receive agricultural information and do not have group membership in the same proportion as men do. Furthermore, households in which women participate as producers are more likely to have noneconomic incentives and water availability (i.e. no problems with water scarcity) to implement AWD. Women participate in manual weed control as hired labor and men participate more in irrigation, and both activities can be affected by the implementation of AWD. For AWD to be widely implemented in Colombia, it is important to target women as well as men and create awareness of the possible social effects of the technology in gendered labor activities, and therefore in the lives of both women and men

Root biomass in cereals, catch crops and weeds can be reliably estimated without considering aboveground biomass

Reliable information on belowground plant biomass is essential to estimate belowground carbon inputs to soils. Estimations of belowground plant biomass are often based on a fixed allometric relationship of plant biomass between aboveground and belowground parts. However, environmental and management factors may affect this allometric relationship making such estimates uncertain and biased. Therefore, we aimed to explore how root biomass for typical cereal crops, catch crops and weeds could most reliably be estimated. Published and unpublished data on aboveground and root biomass (corrected to 0–25 cm depth) of cereal crops (wheat and barley), catch crops and weeds were collected from studies in Denmark. Leave one out cross validation was used to determine the model that could best estimate root biomass. Root biomass varied with year, farming system (organic versus conventional) and cereal species. Shoot and root biomass of catch crops were higher than for weeds (sampled in late autumn), and farming system significantly affected root biomass of catch crops and weeds. The use of fixed root biomass based on the most influential factors (farming system and species) provided the lowest error of prediction for estimation of root biomass, compared with the use of fixed allometric relations, such as root/shoot ratio. For cereal crops, the average root dry matter in organic farming systems was 218 g m−2 (243 and 193 g m−2 for wheat and barley, respectively), but in conventional systems only 139 g m−2 (142 and 129 g m−2 for wheat and barley, respectively). For catch crops and weeds, the root dry matter in organic farming systems were around 127 and 35 g m−2, and in conventional farming systems 75 and 28 g m−2, respectively. In conclusion, the present analysis indicates that root biomass in cereals, catch crops and weeds can be reliably estimated without considering aboveground biomass, and it may be better estimated using fixed values based on species and farming systems than using fixed allometric ratios

Sistema agroforestal Quesungual como fuente natural de emisiones de gases de efecto invernadero en la microcuenca Tecomapa, Somotillo-Nicaragua

 In order to evaluate the emissions of methane and nitrous oxide in the soil through the closed static chamber method in three systems of use; secondary forest, Quesungual agroforestry system and traditional agricultural system, in the Tecomapa micro basin, Somotillo, Nicaragua, seventy-two closed static chambers were established in six farms located in the Tecomapa hydrographic unit, Nicaragua in 2014, to evaluate the emissions of Methane (CH4) and Nitrous Oxide (N2O), in the land use systems: Secondary forest, Quesungual and Traditional agricultural systems. As a result, higher N2O and CH4 emissions were observed in the rainiest month (September 2014). The Quesungual system was CH4 sinks at the level of accumulated net flows (p> F = 0.0133), and the traditional system was the largest emitter of this gas. The greatest emission of N2O tends to occur in the traditional system. Finally, methane gas was positively associated with N2O (r2 = 1; p> F = 0.0533), and WFPS tends to be negatively associated with temperature and CH4 and N2O gases.Con el propósito de evaluar las emisiones de metano y óxido nitroso en el suelo a través del método de cámaras estáticas cerradas en tres sistemas de uso; bosque secundario, sistema agroforestales Quesungual y sistema tradicional agrícola, en la micro cuenca Tecomapa, Somotillo, Nicaragua, setenta y dos cámaras estáticas cerradas fueron establecidas en seis fincas localizadas en la unidad hidrográfica Tecomapa, Nicaragua en 2014, para evaluar las emisiones de Metano (CH4) y Óxido Nitroso (N2O), en los sistemas de uso de suelo: Bosque secundario, Quesungual y Sistema Tradicional agrícola. Como resultado, mayores emisiones de N2O y CH4, se observaron en el mes más lluvioso (septiembre 2014). El sistema Quesungual fue sumideros de CH4 a nivel de flujos netos acumulados (p>F=0.0133), y el sistema tradicional el mayor emisor de este gas. La mayor emisión de N2O tiende a ocurrir en el sistema tradicional. Finalmente el gas metano se asoció positivamente al N2O (r2= 1; p>F= 0.0533), y el WFPS tiende a asociarse negativamente a la temperatura y gases CH4 y N2O

Potential of rice (Oryza sativa L.) cultivars to mitigate methane emissions from irrigated systems in Latin America and the Caribbean

In irrigated rice fields, plant-mediated transfer of CH4 from submerged soils to the atmosphere raise the possibility of genotypic differences in CH4 emissions. Previous research has been contradictory, and varietal differences in rice CH4 emissions in Latin America have not been examined. A field experiment in Colombia tested whether irrigated rice emissions might be reduced using a breeding line, an inbred variety, and two rice hybrids. Data was collected on CH4 emissions, phenotypic, root, and grain yield parameters. Variations observed in CH4 emissions, grain yield, root length, and root surface area were in the order Hybrid 2 > Hybrid 1 > breeding line > inbred variety. CH4 emissions per unit area were between 29% and 62% greater for the hybrids than the inbred variety and breeding line, and CH4 emissions per unit grain yield were comparable across genotypes. Our findings suggest that differences in root characteristics and aboveground biomass explain genetic influences on CH4 emissions. The transition to low-emission rice production systems can be accelerated by using differences in productivity and root qualities among cultivars