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La production animale est une source essentielle de revenus et d'émissions de gaz à effet de serre (GES) agricoles en Colombie, au Brésil, en Argentine, au Costa Rica, en Uruguay, au Mexique et au Pérou. Plusieurs options de gestion et technologiques, avec un potentiel d'atténuation du méthane entérique, ont été évaluées et leur mise à l'échelle devrait contribuer à la réalisation des objectifs de réduction des émissions de GES. Pourtant, l'adoption généralisée d'options d'atténuation prometteuses reste limitée, ce qui soulève des questions quant à savoir si les objectifs de réduction des émissions envisagés sont réalisables. À l'aide de données générées localement, nous explorons les potentiels d'atténuation des technologies et des pratiques de gestion actuellement proposées pour atténuer les émissions de méthane entérique, pour les systèmes de production bovine dans les pays d'Amérique latine les plus émetteurs. Nous discutons ensuite des obstacles à l'adoption d'innovations qui réduisent considérablement les émissions de méthane entérique d'origine bovine et des changements majeurs dans les politiques et les pratiques qui sont nécessaires pour relever les ambitions nationales dans les pays à forte émission. En utilisant la science la plus récente et la pensée actuelle, nous fournissons notre point de vue sur une approche inclusive et ré-imaginons comment les secteurs universitaire, de la recherche, des affaires et des politiques publiques peuvent soutenir et encourager les changements nécessaires pour élever le niveau d'ambition et atteindre les objectifs de développement durable en envisageant des actions allant de la ferme à l'échelle nationale. La producción ganadera es una fuente fundamental de ingresos y emisiones de gases de efecto invernadero (GEI) agrícolas en Colombia, Brasil, Argentina, Costa Rica, Uruguay, México y Perú. Se han evaluado varias opciones de gestión y tecnológicas, con potencial de mitigación de metano entérico, y se prevé que su escalado contribuya al logro de los objetivos de reducción de emisiones de GEI. Sin embargo, la adopción generalizada de opciones de mitigación prometedoras sigue siendo limitada, lo que plantea dudas sobre si los objetivos de reducción de emisiones previstos son alcanzables. Utilizando datos generados localmente, exploramos los potenciales de mitigación de las tecnologías y prácticas de manejo actualmente propuestas para mitigar las emisiones de metano entérico, para los sistemas de producción ganadera en los países de mayor emisión de América Latina. Luego discutimos las barreras para adoptar innovaciones que reduzcan significativamente las emisiones de metano entérico en el ganado y los cambios importantes en las políticas y prácticas que se necesitan para aumentar las ambiciones nacionales en los países con altas emisiones. Utilizando la ciencia más reciente y el pensamiento actual, brindamos nuestra perspectiva sobre un enfoque inclusivo y reimaginamos cómo los sectores académico, de investigación, empresarial y de políticas públicas pueden apoyar e incentivar los cambios necesarios para elevar el nivel de ambición y alcanzar los objetivos de desarrollo sostenible considerando acciones desde la granja hasta la escala nacional. Livestock production is a pivotal source of income and agricultural greenhouse gas (GHG) emissions in Colombia, Brazil, Argentina, Costa Rica, Uruguay, Mexico and Peru. Several management and technological options, with enteric methane mitigation potential, have been evaluated and their scaling is anticipated to contribute towards achieving GHG emission reduction targets. Yet, widespread adoption of promising mitigation options remains limited, raising questions as to whether envisaged emission reduction targets are achievable. Using locally generated data, we explore the mitigation potentials of technologies and management practices currently proposed to mitigate enteric methane emissions, for cattle production systems in the higher emitting countries of Latin America. We then discuss barriers for adopting innovations that significantly reduce cattle-based enteric methane emissions and the major shifts in policy and practice that are needed to raise national ambitions in the high emitting countries. Using the latest science and current thinking, we provide our perspective on an inclusive approach and re-imagine how the academic, research, business and public policy sectors can support and incentivize the changes needed to raise the level of ambition and achieve sustainable development goals considering actions all the way from the farm to the national scale. الإنتاج الحيواني هو مصدر محوري للدخل وانبعاثات غازات الدفيئة الزراعية في كولومبيا والبرازيل والأرجنتين وكوستاريكا وأوروغواي والمكسيك وبيرو. تم تقييم العديد من خيارات الإدارة والخيارات التكنولوجية، مع إمكانية تخفيف الميثان المعوي، ومن المتوقع أن يساهم قياسها في تحقيق أهداف خفض انبعاثات غازات الدفيئة. ومع ذلك، لا يزال الاعتماد الواسع النطاق لخيارات التخفيف الواعدة محدودًا، مما يثير تساؤلات حول ما إذا كانت أهداف خفض الانبعاثات المتوخاة قابلة للتحقيق. باستخدام البيانات التي تم إنشاؤها محليًا، نستكشف إمكانات التخفيف من التقنيات وممارسات الإدارة المقترحة حاليًا للتخفيف من انبعاثات الميثان المعوية، لأنظمة إنتاج الماشية في البلدان ذات الانبعاثات الأعلى في أمريكا اللاتينية. ثم نناقش العوائق التي تحول دون اعتماد الابتكارات التي تقلل بشكل كبير من انبعاثات الميثان المعوي القائم على الماشية والتحولات الرئيسية في السياسات والممارسات اللازمة لرفع الطموحات الوطنية في البلدان ذات الانبعاثات العالية. باستخدام أحدث العلوم والتفكير الحالي، نقدم وجهة نظرنا حول نهج شامل ونعيد تصور كيف يمكن للقطاعات الأكاديمية والبحثية وقطاع الأعمال والسياسة العامة دعم وتحفيز التغييرات اللازمة لرفع مستوى الطموح وتحقيق أهداف التنمية المستدامة مع الأخذ في الاعتبار الإجراءات على طول الطريق من المزرعة إلى النطاق الوطني.

Biomass pre-treatment is a key step in achieving the economic competitiveness of biomass conversion. In the present work, an imidazole pre-treatment process was performed and evaluated using wheat straw and eucalyptus residues as model feedstocks for agriculture and forest-origin biomasses, respectively. Results showed that imidazole is an efficient pre-treatment agent; however, better results were obtained for wheat straw due to the recalcitrant behavior of eucalyptus residues. The temperature had a stronger effect than time on wheat straw pre-treatment but at 160 °C and 4 h, similar results were obtained for cellulose and hemicellulose content from both biomasses (ca. 54% and 24%, respectively). Lignin content in the pre-treated solid was higher for eucalyptus residues (16% vs. 4%), as expected. Enzymatic hydrolysis, applied to both biomasses after different pre-treatments, revealed that results improved with increasing temperature/time for wheat straw. However, these conditions had no influence on the results for eucalyptus residues, with very low glucan to glucose enzymatic hydrolysis yield (93% for wheat straw vs. 40% for eucalyptus residues). Imidazole can therefore be considered as a suitable solvent for herbaceous biomass pre-treatment.

Since the 1970s but with greater intensity in the 1980s, strong, social, economic, and cultural transformations have led to the post-Fordist or post-productivist countryside determining what researchers identify as “rural restructuring” [...]

From the comparison of regulations and/or standards for the organic, conventional and/or integrated citrus production method and a voluntary certification, it emerges that farms certified with voluntary non-regulated certification systems, such as the IFA FV GLOBALG.A.P, are obliged to take into account the highest number of aspects, reported in a more complete register, than the organic ones. Moreover, this is also supported by a continuous-time planned process of revision and updating of the applicable versions of the standard. The environmental impact of the food production, the safety aspects of food products, as well as the health, ethics, and safety aspects of workers, are largely considered and inspected in the GLOBALG.A.P., while the organic system, despite the IFOAM suggestions and indications, is only considered partially. This means that, from a practical point of view, the organic product can be considered “clean and safe”, but not more environmentally friendly than the GLOBALG.A.P. products.

Shrub encroachment influences several ecosystem services in drylands worldwide. Yet, commonly used strategies to reduce encroachment show a low medium-term success, calling for a better understanding of its causes. Previous works identified multiple drivers responsible for this phenomenon, including anthropogenic and environmental causes. However, the relative effect of climate, topography and edaphic factors on shrub encroachment is not fully understood nor has been properly quantified in Mediterranean Basin drylands. Also, understanding how these drivers lead to changes in plant communities' functional traits associated to shrub encroachment is crucial, considering traits influence ecosystem processes and associated ecosystem services. Here, we studied the understory of a Mediterranean dryland ecosystem composed of savanna-like Holm-oak woodlands, along a regional climatic gradient. We specifically assessed (i) how climatic, topographic and edaphic factors influence understory relative shrub cover (RSC) and (ii) their direct and indirect effects (via RSC) on plant functional traits. We studied the mean and diversity of 12 functional traits related to plant regeneration, establishment, and dispersal, at the community-level. We found that, under similar low-intensity land use, topographic and edaphic factors, namely slope variations and soil C:N ratio, were the most important predictors of shrub encroachment, determining communities' functional characteristics. Climate, namely summer precipitation, had a much lesser influence. Our model explained 52% of the variation in relative shrub cover. Climate had a stronger effect on a set of functional traits weakly involved in shrub encroachment, related to flowering and dispersal strategies. We show that shrub encroachment is largely predicted by topo-edaphic factors in Mediterranean drylands subject to conventional low-intensity land use. Hence, management strategies to reduce encroachment need to take these drivers into account for efficient forecasting and higher cost-effectiveness. Our results suggest that climate change might not greatly impact shrub encroachment in the Mediterranean Basin, but may affect functional structure and reduce functional diversity of plant communities, thus affecting ecosystem functioning.

Abstract. This paper aims to assess the spatial variability in the response of CO2 exchange to irradiance across the Arctic tundra during peak season using light response curve (LRC) parameters. This investigation allows us to better understand the future response of Arctic tundra under climatic change. Peak season data were collected during different years (between 1998 and 2010) using the micrometeorological eddy covariance technique from 12 circumpolar Arctic tundra sites, in the range of 64–74° N. The LRCs were generated for 14 days with peak net ecosystem exchange (NEE) using an NEE–irradiance model. Parameters from LRCs represent site-specific traits and characteristics describing the following: (a) NEE at light saturation (Fcsat), (b) dark respiration (Rd), (c) light use efficiency (α), (d) NEE when light is at 1000 μmol m−2 s−1 (Fc1000), (e) potential photosynthesis at light saturation (Psat) and (f) the light compensation point (LCP). Parameterization of LRCs was successful in predicting CO2 flux dynamics across the Arctic tundra. We did not find any trends in LRC parameters across the whole Arctic tundra but there were indications for temperature and latitudinal differences within sub-regions like Russia and Greenland. Together, leaf area index (LAI) and July temperature had a high explanatory power of the variance in assimilation parameters (Fcsat, Fc1000 and Psat, thus illustrating the potential for upscaling CO2 exchange for the whole Arctic tundra. Dark respiration was more variable and less correlated to environmental drivers than were assimilation parameters. This indicates the inherent need to include other parameters such as nutrient availability, substrate quantity and quality in flux monitoring activities.