• Energy Research
• agricultural and veterinary science... close
• 2. Zero hunger close
• GB close
• AU close
• IT close

Atmospheric concentrations of the greenhouse gas nitrous oxide (N(2)O) have increased significantly since pre-industrial times owing to anthropogenic perturbation of the global nitrogen cycle, with animal production being one of the main contributors. Grasslands cover about 20 per cent of the temperate land surface of the Earth and are widely used as pasture. It has been suggested that high animal stocking rates and the resulting elevated nitrogen input increase N(2)O emissions. Internationally agreed methods to upscale the effect of increased livestock numbers on N(2)O emissions are based directly on per capita nitrogen inputs. However, measurements of grassland N(2)O fluxes are often performed over short time periods, with low time resolution and mostly during the growing season. In consequence, our understanding of the daily and seasonal dynamics of grassland N(2)O fluxes remains limited. Here we report year-round N(2)O flux measurements with high and low temporal resolution at ten steppe grassland sites in Inner Mongolia, China. We show that short-lived pulses of N(2)O emission during spring thaw dominate the annual N(2)O budget at our study sites. The N(2)O emission pulses are highest in ungrazed steppe and decrease with increasing stocking rate, suggesting that grazing decreases rather than increases N(2)O emissions. Our results show that the stimulatory effect of higher stocking rates on nitrogen cycling and, hence, on N(2)O emission is more than offset by the effects of a parallel reduction in microbial biomass, inorganic nitrogen production and wintertime water retention. By neglecting these freeze-thaw interactions, existing approaches may have systematically overestimated N(2)O emissions over the last century for semi-arid, cool temperate grasslands by up to 72 per cent.

With an approach combining crop modelling and biotechnology to assess the performance of three durum wheat cultivars (Creso, Duilio, Simeto) in a climate change context, weather and agronomic datasets over the period 1973–2004 from two sites, Benatzu and Ussana (Southern Sardinia, Itay), were used and the model responses were interpreted considering the role of DREB genes in the genotype performance with a focus on drought conditions. The CERES-Wheat crop model was calibrated and validated for grain yield, earliness and kernel weight. Forty-eight synthetic scenarios were used: 6 scenarios with increasing maximum air temperature; 6 scenarios with decreasing rainfall; 36 scenarios combining increasing temperature and decreasing rainfall. The simulated effects on yields, anthesis and kernel weights resulted in yield reduction, increasing kernel weight, and shortened growth duration in both sites. Creso (late cultivar) was the most sensitive to simulated climate conditions. Simeto and Duilio (early cultivars) showed lower simulated yield reductions and a larger anticipation of anthesis date. Observed data showed the same responses for the three cultivars in both sites. The CERES-Wheat model proved to be effective in representing reality and can be used in crop breeding programs with a molecular approach aiming at developing molecular markers for the resistance to drought stress.

This study investigated the metabolizable energy (ME) intake, net energy of production (NEp), heat production (HP), efficiencies of ME use for energy, lipid and protein retention as well as the performance of broiler chickens fed diets based on cassava chips or pellets with or without supplementation with an enzyme product containing xylanase, amylase, protease and phytase. The two products, cassava chips and pellets, were analysed for nutrient composition prior to feed formulation. The cassava chips and pellets contained 2.2% and 2.1% crude protein; 1.2% and 1.5% crude fat; and 75.1% and 67.8% starch, respectively. Lysine and methionine were 0.077%, 0.075%, and 0.017%, 0.020% protein material, respectively, while calculated ME was 12.6 and 11.7 MJ/kg, respectively. Feed intake to day 21 was lower (p<0.01) on the diet containing cassava chips compared to diets with cassava pellets. Enzyme supplementation increased (p<0.01) feed intake on all diets. Live weight at day 21 was significantly (p<0.01) reduced on the diet based on cassava chips compared to pellets, but an improvement (p<0.01) was noticed with the enzyme supplementation. Metabolizable energy intake was reduced (p<0.01) by both cassava chips and pellets, but was increased (p<0.01) on all diets by enzyme supplementation. The NEp was higher (p<0.01) in the maize-based diets than the diets containing cassava. Enzyme supplementation improved (p<0.01) NEp in all the diets. Heat production was highest (p<0.01) on diets containing cassava pellets than on cassava chips. It is possible to use cassava pellets in diets for broiler chickens at a level close to 50% of the diet to reduce cost of production, and the nutritive value of such diets can be improved through supplementation of enzyme products containing carbohydrases, protease, and phytase.

Two chickpea genotypes viz. Bhakar-2011 (desi) and Noor-2013 (kabuli) were sown in soil filled pots supplied with low (0.3 mg kg-1) and high (3 mg kg-1 soil) zinc (Zn) under control (70% water holding capacity and 25/20 °C day/night temperature), drought (35% water holding capacity) and heat (35/30 °C day/night temperature) stresses. Drought and heat stresses reduced rate of photosynthesis, photosystem II efficiency, plant growth and Zn uptake in chickpea. Low Zn supply exacerbated adverse effects of drought and heat stresses in chickpea, and caused reduction in plant biomass, carbon assimilation, antioxidant activity, impeded Zn uptake and enhanced oxidative damage. However, adequate Zn supply ameliorated adverse effect of drought and heat stresses in both chickpea types. The improvements were more in desi than kabuli type. Adequate Zn nutrition is crucial to augment growth of chickpea plants under high temperature and arid climatic conditions.

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.

Reducing methane (CH4) emission from paddy rice production is an important target for many Asian countries in order to comply with their climate policy commitments. National greenhouse gas (GHG) inventory approaches like the Tier-2 approach of the Intergovernmental Panel on Climate Change (IPCC) are useful to assess country-scale emissions from the agricultural sector. In paddy rice, alternate wetting and drying (AWD) is a promising and well-studied water management technique which, as shown in experimental studies, can effectively reduce CH4 emissions. However, so far little is known about GHG emission rates under AWD when the technique is fully controlled by farmers. This study assesses CH4 and nitrous oxide (N2O) fluxes under continuous flooded (CF) and AWD treatments for seven subsequent seasons on farmers’ fields in a pumped irrigation system in Central Luzon, Philippines. Under AWD management, CH4 emissions were substantially reduced (73% in dry season (DS), 21% in wet season (WS)). In all treatments, CH4 is the major contributor to the total GHG emission and is, thus, identified as the driving force to the global warming potential (GWP). The contribution of N2O emissions to the GWP was higher in CF than in AWD, however, these only offset 15% of the decrease in CH4 emission and, therefore, did not jeopardize the strong reduction in the GWP. The study proves the feasibility of AWD under farmers’ management as well as the intended mitigation effect. Resulting from this study, it is recommended to incentivize dissemination strategies in order to improve the effectiveness of mitigation initiatives. A comparison of single CH4 emissions to calculated emissions with the IPCC Tier-2 inventory approach identified that, although averaged values showed a sufficient degree of accuracy, fluctuations for single measurement points have high variation which limit the use of the method for field-level assessments.

The first decade of the new millennium saw a boom in rubber prices. This led to rapid and widespread land conversion to monoculture rubber plantations in continental SE Asia, where natural rubber production has increased >50% since 2000. Here, we analyze the subsequent spread of rubber between 2005 and 2010 in combination with environmental data and reports on rubber plantation performance. We show that rubber has been planted into increasingly sub-optimal environments. Currently, 72% of plantation area is in environmentally marginal zones where reduced yields are likely. An estimated 57% of the area is susceptible to insufficient water availability, erosion, frost, or wind damage, all of which may make long-term rubber production unsustainable. In 2013 typhoons destroyed plantations worth US$ >250 million in Vietnam alone, and future climate change is likely to lead to a net exacerbation of environmental marginality for both current and predicted future rubber plantation area. New rubber plantations are also frequently placed on lands that are important for biodiversity conservation and ecological functions. For example, between 2005 and 2010 >2500 km(2) of natural tree cover and 610 km(2) of protected areas were converted to plantations. Overall, expansion into marginal areas creates potential for loss-loss scenarios: clearing of high-biodiversity value land for economically unsustainable plantations that are poorly adapted to local conditions and alter landscape functions (e.g. hydrology, erosion) - ultimately compromising livelihoods, particularly when rubber prices fall. (C) 2015 Elsevier Ltd. All rights reserved.