Promoción y desarrollo de agronegocios desde la perspectiva de la innovación tecnológica

El documento inicialmente presenta una visión global de la situación y perspectivas de los agronegocios en los países de ALC, con foco en cadenas agro-exportadoras. Posteriormente, se analizan las políticas y acciones que los países de la región han estado fortaleciendo para promover los agronegocios, así como los cambios estructurales e institucionales que han ocurrido en este contexto. La segunda parte analiza los principales instrumentos que se han puesto en práctica para el incentivo de la innovación en los Agronegocios. Se finaliza con los temas sugeridos para la construcción de una agenda en el marco del FORAGRO, que dé sustento a acciones conjuntas de cooperación, intercambio y desarrollo, para el fortalecimiento de la innovación en los agronegocios de los países de A

Physicochemical and Ecotoxicological Assessment of Biochar for Environmental Application

Multiple benefits of biochar conversion and utilization, including soil carbon sequestration and environmental remediation, have been proposed by researchers. Biochar may be produced from a wide array of feedstocks and pyrolytic process conditions. This influences the final biochar composition, which includes the presence of potential pollutants that could ultimately result in detrimental environmental impacts. The major purpose of this research was to improve our understanding of potential unintended effects of biochar addition to the environment either as a potential source of toxicity towards organisms or as a material influencing availabilities of other soil contaminants. Biochars were produced from ten different feedstocks at pyrolysis temperatures from 350 to 650 °C, and characterized for total and bioavailable elemental composition, PAHs as well as other intrinsic properties. Bioassays that included the bacterium Vibrio fischeri, the alga Pseudokirchneriella subcapitata, and the plants Lepidium sativum and Sorghum saccharatum were employed to evaluate biochar ecotoxicity. Despite many samples yielding an acceptable pollutant content based on the International Biochar Initiative standard, 28 % of biochar samples were considered toxic for organisms (≥ 50% inhibition), which emphasized the need to complement the traditional analytical characterization of ecotoxicological criteria. The inhibition effect found on biochars produced from cattle manure, poultry litter, and rice straw was attributed to salinity stress, mostly caused by high potassium concentrations. In addition, greater toxicity was detected in feedstocks pyrolyzed at 350 °C compared to higher temperatures, which was presumed to be associated with some VOCs. Regardless of the hazard classification obtained by cattle manure-based biochar, its addition into an acid soil at 20 g kg-1 was effective in alleviating the soil toxicity caused by exchangeable aluminum, which highlighted the importance of guiding biochar users in management recommendations of salt-rich biochar. Biochar added to soil affected the dissipation parameters and the ecotoxicological properties of herbicides, which resulted in an enhancement of metolachlor dissipation, an increase in the persistence of trifluralin, a greater inhibition of bacterial luminescence, and a toxicity reduction to plants with respect to non-amended soil. The present research provided valuable information about the importance of responsible and sustainable use of biochar

Yield-scaled global warming potential of two irrigation management systems in a highly productive rice system

Water management impacts both methane (CH4) and nitrous oxide (N2O) emissions from rice paddy fields. Although controlled irrigation is one of the most important tools for reducing CH4emission in rice production systems it can also increase N2O emissions and reduce crop yields. Over three years, CH4 and N2O emissions were measured in a rice field in Uruguay under two different irrigation management systems, using static closed chambers: conventional water management (continuous flooding after 30 days of emergence, CF30); and an alternative system (controlled deficit irrigation allowing for wetting and drying, AWDI). AWDI showed mean cumulative CH4 emission values of 98.4 kg CH4 ha−1, 55 % lower compared to CF30, while no differences in nitrous oxide emissions were observed between treatments ( p >; 0.05). No yield differences between irrigation systems were observed in two of the rice seasons ( p >; 0.05) while AWDI promoted yield reduction in one of the seasons ( p< 0.05). When rice yield and greenhouse gases (GHG) emissions were considered together, the AWDI irrigation system allowed for lower yield-scaled total global warming potential (GWP). Higher irrigation water productivity was achieved under AWDI in two of the three rice seasons. These findings suggest that AWDI could be an option for reducing GHG emissions and increasing irrigation water productivity. However, AWDI may compromise grain yield in certain years, reflecting the importance of the need for fine tuning of this irrigation strategy and an assessment of the overall tradeoff between relationships in order to promote its adoption by farmers

Yield-scaled global warming potential of two irrigation management systems in a highly productive rice system

ABSTRACT Water management impacts both methane (CH4) and nitrous oxide (N2O) emissions from rice paddy fields. Although controlled irrigation is one of the most important tools for reducing CH4emission in rice production systems it can also increase N2O emissions and reduce crop yields. Over three years, CH4 and N2O emissions were measured in a rice field in Uruguay under two different irrigation management systems, using static closed chambers: conventional water management (continuous flooding after 30 days of emergence, CF30); and an alternative system (controlled deficit irrigation allowing for wetting and drying, AWDI). AWDI showed mean cumulative CH4 emission values of 98.4 kg CH4 ha−1, 55 % lower compared to CF30, while no differences in nitrous oxide emissions were observed between treatments ( p > 0.05). No yield differences between irrigation systems were observed in two of the rice seasons ( p > 0.05) while AWDI promoted yield reduction in one of the seasons ( p< 0.05). When rice yield and greenhouse gases (GHG) emissions were considered together, the AWDI irrigation system allowed for lower yield-scaled total global warming potential (GWP). Higher irrigation water productivity was achieved under AWDI in two of the three rice seasons. These findings suggest that AWDI could be an option for reducing GHG emissions and increasing irrigation water productivity. However, AWDI may compromise grain yield in certain years, reflecting the importance of the need for fine tuning of this irrigation strategy and an assessment of the overall tradeoff between relationships in order to promote its adoption by farmers