Increasing beef production won’t reduce emissions

BP is supported by a grant from CAPES (Coordenação de Aperfeiçoamento de Pessoal de Nível Superior) through the Brazilian Science without Borders programme (number 88881.068115/2014-01). He thanks Luciana Leite de Araújo for suggesting the topic of this letter.Peer reviewedPostprin

Long-Term Impacts of Stocking Rate on Soil Carbon Sequestration in Arid Areas of South Africa

Overstocking is one of the most important factors which results in changes of carbon stocks (Reeder and Schuman, 2002) and soil degradation, particularly in sandy soil, vulnerable to degradation through physical erosion. South African (RSA) topsoil is characterized by the low level of organic matter (Du Preez et al. 2011). Like most other African countries, little is known about the level of C sequestration under various grazing strategies in the vast dry grassland areas of RSA. It is well known that long-term studies with various stocking rate would be able to shed light on the level of C sequestration in varying soil types (Peneiro et al. 2010). Although studies have been undertaken concerning impacts of grazing on vegetation dynamics in RSA (Du Toit 2000), only few have focused on soil carbon stocks. Hence, this study was designed to assess impacts of long-term grazing at different stocking rate on carbon sequestration in Grootfontein, South Africa

Ensuring Access to Safe and Nutritious Food for All Through Transformation of Food Systems : A paper on Action Track 1

Action Track 1 of the Food Systems Summit offers an opportunity to bring together the crucial elements of food safety, nutrition, poverty and inequalities in the framework of food systems in the context of climate and environmental change to ensure that all people have access to a safe and nutritious diet. Achieving Action Track 1 goal is essential to the achievement of the goals of the other Action Tracks. With less than a decade left to achieve the Sustainable Development Goals (SGD), most countries are not on target to achieve the World Health Organisation’s nutrition targets and SGD 2 targets. The COVID pandemic has exacerbated malnutrition and highlighted the need for food safety. The pandemic has also exposed the deep inequalities in society and food systems. Yet, future food systems can address many of these failings and ensure safe and nutritious food for all. However, structural change is necessary to address the socio-economic drivers behind malnutrition, inequalities and the climate and environmental impacts of food. Adopting a whole-system approach in policy, research and monitoring and evaluation is crucial to manage trade-off and externalities from farm-level to national scales and across multiple sectors and agencies. Supply chain failures will need to be overcome and technology solutions adopted and adapted to specific contexts. A transformation of food systems requires coordinating changes in supply and demand in differentiated ways across world regions: bridging yield gaps and improving livestock feed conversion, largely through agro-ecological practices, deploying at scale soil carbon sequestration and greenhouse gas mitigation, reducing food losses and wastes, as well as over-nourishment and shifting the diets of wealthy populations. Global food systems sustainability also requires halting the expansion of agriculture into fragile ecosystems, while restoring degraded forests, fisheries, rangelands, peatlands and wetlands. Shifting to more sustainable consumption and production patterns within planetary boundaries will require efforts to influence food demand and diets, diversify food systems, careful land-use planning and management. Integrative policies need to ensure that food prices reflect real costs (including major externalities caused by climate change, land degradation and biodiversity loss, and public health impacts of malnutrition), reduce food waste and, at the same time, ensure safe and healthy food affordability, decent incomes and wages for farmers and food system workers. Harnessing science and technology solutions and sharing actionable knowledge with all players in the food system offers many opportunities. Greater coordination of food system stakeholders is crucial for greater inclusion, greater transparency and more accountability. Sharing lessons and experiences will foster adaptive learning and responsive actions. Careful consideration of the trade-offs, externalities and costs of not acting is needed to ensure that the changes we make benefit to all and especially the most vulnerable in society

Variation in carbon footprint of milk due to management differences between Swedish dairy farms

To identify mitigation options to reduce greenhouse gas (GHG) emissions from milk production (i.e. the carbon footprint (CF) of milk), this study examined the variation in GHG emissions among dairy farms using data from previous CF studies on Swedish milk. Variation between farms in these production data, which were found to have a strong influence on milk CF were obtained from existing databases of e.g. 1051 dairy farms in Sweden in 2005. Monte Carlo analysis was used to analyse the impact of variations in seven important parameters on milk CF concerning milk yield (energy corrected milk (ECM) produced and delivered), feed dry matter intake (DMI), enteric methane emissions, N content in feed DMI, N-fertiliser rate and diesel used on farm. The largest between farm variation among the analysed production data were N-fertiliser rate (kg/ha) and diesel used (l/ha) on farm (coefficient of variation (CV) 31-38%). For the parameters concerning milk yield and feed DMI the CV was approx. 11 and 8%, respectively. The smallest variation in production data was found for N content in feed DMI. According to the Monte Carlo analysis, these variations in production data led to a variation in milk CF of between 0.94 and 1.33 kg CO2 equivalents (CO2e) per kg ECM, with an average value of 1.13 kg/CO2e kg ECM. We consider that this variation of ±17% that was found based on the used farm data would be even greater if all Swedish dairy farms were included, as the sample of farms in this study was not totally unbiased. The variation identified in milk CF indicates that a potential exists to reduce GHG emissions from milk production on both national and farm level through changes in management. As milk yield and feed DMI are two of the most influential parameters for milk CF, feed conversion efficiency (i.e. units ECM produced per unit DMI) can be used as a rough key performance indicator for predicting CF reductions. However, it must be borne in mind that feeds have different CF due to where and how they are produced

Chapter 2. Agricultural management, livestock and food security

Over the centuries, farmers from the countries bordering the Mediterranean have developed a variety of agricultural practices, providing a wide array of commodities that have made the Mediterranean diet world famous. However, climate change projections reveal that some of these practices are at risk because of the expected drier and hotter conditions coupled with soil and water constraints, as well as a higher fire frequency threat. Nevertheless, adapting to climate hazards has long been part of farming practice in this area. The growing of pulses or other drought-tolerant crops (olives, grapes, almonds, etc.), transhumance and the use of rangelands or tree fodder by livestock, as well as water harvesting techniques, are among some of the age-old solutions to erratic rainfall or hot summers. In this chapter, we highlight some of the challenges facing agriculture in the Mediterranean and provide a series of examples of how agricultural and livestock management can be better adapted to climate change.Reliable metrics are necessary to enable the impact of climate change to be assessed and targeted agricultural policies to be designed. Long-term environmental observatories are essential to improve land management in the context of global change. Modelling the projected effects of current climatic trends shows that regional agricultural import dependence will increase as the impacts of climate change become more severe. Small ruminants (sheep, goats) have a good adaptation potential and can play a food security net role under climate change with a view to responding to the local food demand that emerges with new life styles. Local small ruminant breeds are adapted to harsh environments but this unique genetic heritage is now endangered. Perennial forage grasses are an alternative to cereals due to lower input requirement, year-round soil cover and optimal use of water. Mediterranean fruit trees, although well adapted, face increases in temperature and soil salinity as well as decreases in water availability. They will require improvements such as selection of early flowering varieties (olive), assessment of best pollinating conditions (figs) and salt tolerant rootstock (citrus).Depuis des siècles, les agriculteurs de la zone méditerranéenne ont mis au point une large gamme de pratiques agricoles à l’origine de productions qui ont rendu le régime alimentaire méditerranéen célèbre dans le monde entier. Les projections climatiques montrent cependant que des risques de sécheresse et de température élevée, associés à des contraintes concernant le sol, l’eau et les dangers d’incendie, menacent certaines de ces pratiques. L’adaptation à l’aléa climatique est néanmoins une habitude ancienne dans cette zone. La culture de légumes secs ou d’autres cultures tolérantes à la sécheresse (olives, raisin, amandes, etc.), la transhumance, l’utilisation des terrains de parcours et du fourrage arboré par le bétail, ou encore les techniques de capture de l’eau, font partie de ces solutions ancestrales au problème de la pluviométrie irrégulière ou des étés caniculaires. Dans ce chapitre, nous présentons certains des défis auxquels l’agriculture méditerranéenne est confrontée et nous proposons quelques exemples illustrant l’adaptation de l’agriculture et de l’élevage au changement climatique. Pour évaluer l’impact du changement climatique et concevoir des politiques agricoles appropriées, des mesures fiables sont nécessaires. Pour améliorer la gestion des terres dans un contexte de changement climatique, des observatoires environnementaux à long terme sont indispensables. La modélisation des effets attendus du changement climatique montre que la région deviendra progressivement plus dépendante des importations agricoles. Les petits ruminants (moutons, chèvres) ont un fort potentiel d’adaptation et peuvent jouer un rôle de filet de sécurité alimentaire en accord avec les nouvelles exigences alimentaires liées à de nouveaux styles de vie. Les races locales de petits ruminants sont adaptées à des environnements contraignants mais ce patrimoine génétique est désormais menacé. Les graminées fourragères pérennes représentent une alternative aux céréales en raison de leurs exigences modestes en intrants, de leur capacité à couvrir le sol toute l’année et de leur utilisation optimale de l’eau. Bien qu’ils soient bien adaptés, les arbres fruitiers méditerranéens sont confrontés à l’augmentation de la température et de la salinité du sol ainsi qu’à une diminution des réserves en eau. Ils devront faire l’objet d’améliorations comme la sélection de variétés à floraison précoce (oliviers), la prise en compte des conditions de pollinisation (figuiers) ou le greffage sur des porte-greffes tolérants à la salinité (agrumes)

Potential of legume-based grassland-livestock systems in Europe

European grassland-based livestock production systems face the challenge of producing more meat and milk to meet increasing world demands and to achieve this using fewer resources. Legumes offer great potential for achieving these objectives. They have numerous features that can act together at different stages in the soil–plant–animal–atmosphere system, and these are most effective in mixed swards with a legume proportion of 30–50%. The resulting benefits include reduced dependence on fossil energy and industrial N-fertilizer, lower quantities of harmful emissions to the environment (greenhouse gases and nitrate), lower production costs, higher productivity and increased protein self-sufficiency. Some legume species offer opportunities for improving animal health with less medication, due to the presence of bioactive secondary metabolites. In addition, legumes may offer an adaptation option to rising atmospheric CO2 concentrations and climate change. Legumes generate these benefits at the level of the managed land-area unit and also at the level of the final product unit. However, legumes suffer from some limitations, and suggestions are made for future research to exploit more fully the opportunities that legumes can offer. In conclusion, the development of legume-based grassland–livestock systems undoubtedly constitutes one of the pillars for more sustainable and competitive ruminant production systems, and it can be expected that forage legumes will become more important in the future

Impact of droughts on the carbon cycle in European vegetation : a probabilistic risk analysis using six vegetation models

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