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Intensifying pastoralism may not reduce greenhouse gas emissions: Wildlife-dominated landscape scenarios as a baseline in life-cycle analysis

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Abstract

Livestock-related Life Cycle Analyses (LCA) have consistently identified extensive livestock systems as the most emission-intense sources of greenhouse gases, which has triggered calls for a livestock intensification policy, including the promotion of monogastrics in zero-grazing systems. This is in contrast with advocates for pastoralist systems that depict them as biodiversity-friendly and helpful against land degradation. Here we reconcile both perspectives by showing that grazed ecosystems have a certain level of natural baseline emissions, which will be caused either by free ranging livestock or by wild animals able to digest cellulose. Such emissions cannot be considered anthropogenic and policies aimed at intensifying pastoralist production will therefore not have a positive effect on climate change. Future LCA should include baseline emissions from ecosystems.

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... Beef cattle production has increased in the last three decades almost 40% worldwide, with the Americas being one of the regions that led this development [1]. However, beef produced from native grassland ecosystems provides multiple benefits such as biodiversity conservation, low energy and inputs consumption, carbon sequestration in soils, improved animal welfare, and rural development [2,3]. ...
... After the CoP21 meeting in Paris, there was a multinational agreement to act against climate change and that includes interventions in the livestock sector, by reducing methane emissions per unit of product (carbon footprint), in association with the promotion of sustainable grazing practices, so that the associated benefits of pastoralism are not sacrificed [3]. In this sense, using herbage mass efficiently by managing allowance per animal, is a key mitigation option in beef cow-calf grazing systems that can increase beef productivity and reduce carbon footprint [1]. ...
... Means within the same row followed by different letters are significantly different at p < 0.05. Organic matter digestibility, 2 Organic matter intake,3 Dry matter intake,4 Live weight , adjusted for uterine weight. ...
Article
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The aim of this study was to measure methane emissions (CH4) and herbage intake, and, on the basis of these results, obtain the methane yield (MY, methane yield as g CH4/kg dry matter intake (DMI) and Ym, methane yield as a percentage of Gross Energy intake), from beef cows grazing on native grasslands. We used forty pregnant heifers, with two treatments of herbage allowance (HA) adjusted seasonally (8 and 5 kg dry matter (DM)/kg cattle live weight (LW), on average), during autumn, winter and spring. Methane emissions (207 g CH4/d), organic matter intake (OMI, 7.7 kg organic matter (OM)/d), MY (23.6 g CH4/kg DMI) and Ym (7.4%), were similar between treatments. On the other hand, all variables had a marked increase in spring (10.8 kg OM/d and 312 g CH4/d), except for Ym. The methane emission factor from Intergovernmental Panel on Climate Change (IPCC) Tier 2 estimated with these results was 78 kg CH4/head/year. The results show that methane emissions and intake were influenced by the season, but not by the HA analyzed in this study. This information for cow–calf systems in native grasslands in Uruguay can be used in National greenhouse gases (GHG) inventories, representing a relevant contribution to global GHG inventories.
... This claim, however, needs to be scrutinized, as pastoralism not only provides wealth and nourishment to societies, but also provides other valuable ecosystem services, as stated above, and has the potential to obtain a neutral carbon balance (Assouma et al., 2019). Moreover, the opening of pastoral lands to rewilding needs careful consideration (Manzano and White, 2019), as it would ultimately lead to an increase in other methanogenic animals that do not significantly contribute to human nutrition and livelihoods (i.e., wild ruminants and termites). Although current domesticated ruminants produce large amounts of CH 4 , this may be comparable to historical wildlife (Hristov, 2012;Zimov and Zimov, 2014), with wild herbivores being less efficient in feed conversion (Manzano and White, 2019). ...
... Moreover, the opening of pastoral lands to rewilding needs careful consideration (Manzano and White, 2019), as it would ultimately lead to an increase in other methanogenic animals that do not significantly contribute to human nutrition and livelihoods (i.e., wild ruminants and termites). Although current domesticated ruminants produce large amounts of CH 4 , this may be comparable to historical wildlife (Hristov, 2012;Zimov and Zimov, 2014), with wild herbivores being less efficient in feed conversion (Manzano and White, 2019). ...
... Considerable progress can be achieved for monogastrics, by focusing on their potential for recycling food waste and leftovers Van Zanten et al., 2018;Uwizeye et al., 2019), as well as for ruminants, by adjustment of the grazing management and taxonomical and biochemical dietary diversity of ruminants at individual and herd level (Gregorini et al., 2017), improved channeling of waste streams, and better integration in the circular bioeconomy (Fairlie, 2011;Teague et al., 2016;Stanley et al., 2018). Rather than losing grasslands to annual agriculture and biofuel production, this includes working with the carbon storage potential of grasslands and rangelands, the added value of trees, the adoption of improved pasture species, better veterinary care, etc., which are also forms of intensification, in their own right (Manzano and White, 2019). This offers an entirely different mindset than the linear approach of Cartesian, mechanical thinking. ...
Article
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Humanity’s main societal and epistemic transitions also mirror changes in its approach to the food system. This particularly holds true for human–animal interactions and the consumption of animal source foods (red meat especially, and to a lesser degree dairy, eggs, poultry, and fish). Hunter-gathering has been by far the longest prevailing form of human sustenance, followed by a diffuse transition to crop agriculture and animal husbandry. This transition eventually stabilized as a state-controlled model based on the domestication of plants, animals, and humans. A shift to a post-domestic paradigm was initiated during the 19th century in the urbanizing populations of the Anglosphere, which was characterized by the rise of agri-food corporations, an increased meat supply, and a disconnect of most of its population from the food chain. While this has improved undernutrition, various global threats have been emerging in parallel. The latter include, among others, a public health crisis, climate change, pandemics, and societal class anxieties. This state of affairs is an unstable one, setting the conditions of possibility for a new episteme that may evolve beyond mere adjustments within the business-as-usual model. At least two disruptive scenarios have been described in current food discourses, both by scientists and mass media. Brought to its extreme, the first scenario relates to the radical abolishment of livestock, rewilding, a ‘plants-only’ diet, and vegan ideology. A second option consists of a holistic approach to animal husbandry, involving more harmonic and richer types of human–animal–land interactions. We argue that – instead of reactive pleas for less or none – future thoughtscapes should emphasize ‘more of the better.’
... However, since reduction rates in CH 4 intensity have been much larger than CO 2 increases, such trade-off seems to have had limited warming implications for the future in this particular case. This should, nevertheless, be taken cautiously: the reduction in CH 4 emissions by livestock no longer grazing on marginal areas may have been replaced by methane-emitting wild herbivores that would be occupying their former grazing niches in the ecosystem (Manzano and White, 2019). It is known that European wild herbivores are expanding into abandoned marginal grazing areas (Milner et al., 2006), so the net amount of CH 4 arising from the whole wild and domestic grazing system may have stayed around the same values. ...
... Moreover, these countries have abundant natural grazing ecosystems in their territory that can host many wild methane-producing herbivores. Total abandonment of grazing in natural rangelands is likely to be a very ineffective climate change policy (Manzano and White, 2019). ...
Article
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Recent calls advocate that a huge reduction in the consumption of animal products (including dairy) is essential to mitigate climate change and stabilise global warming below the 1.5 and 2°C targets. The Paris Agreement states that to stabilise temperatures we must reach a balance between anthropogenic emissions by sources and removals by sinks of greenhouse gases (GHG) in the second half of this century. Consequently, many countries have adopted overall GHG reduction targets (e.g. EU, at least 40% by 2030 compared to 1990). However, using conventional metric-equivalent emissions (CO 2 -e GWP 100 ) as the basis to account for emissions does not result in capturing the effect on atmospheric warming of changing emission rates from short-lived GHG (e.g. methane: CH 4 ), which are the main source of GHG emissions by small ruminants. This shortcoming could be solved by using warming-equivalent emissions (CO 2 -we, GWP*), which can accurately link annual GHG emission rates to its warming effect in the atmosphere. In our study, using this GWP* methodology and different modelling approaches, we first examined the historical (1990–2018) contribution of European dairy small ruminant systems to additional atmosphere warming levels and then studied different emission target scenarios for 2100. These scenarios allow us to envision the necessary reduction of GHG emissions from Europe's dairy small ruminants to achieve a stable impact on global temperatures, i.e. to be climatically neutral. Our analysis showed that, using this type of approach, the whole European sheep and goat dairy sector seems not to have contributed to additional warming in the period 1990–2018. Considering each subsector separately, increases in dairy goat production has led to some level of additional warming into the atmosphere, but these have been compensated by larger emission reductions in the dairy sheep sector. The estimations of warming for future scenarios suggest that to achieve climate neutrality, understood as not adding additional warming to the atmosphere, modest GHG reductions of sheep and goat GHG would be required (e.g. via feed additives). This reduction would be even lower if potential soil organic carbon (SOC) from associated pastures is considered.
... Species richness (number of species) 32.33 a ± 2.33 25.00 b ± 2.33 Soil microbial metabolic quotient (mg CO 2 m −2 h −1 /mg microbial C kg −1 soil) 0.93 a ± 0.28 1.20 b ± 0.26 Soil compaction (Mpa) 3.31 a ± 0.86 1.28 b ± 0.21 CN ratio 24.51 a ± 0.35 29.06 b ± 0.88 albedo are highly context-dependent (Bond et al. 2019), potentially counterproductive (Nuñez et al. 2021), and subject to large uncertainties as landscapes will be colonized by wild ruminants and other methane emitters (Manzano and White 2019). In terms of biodiversity, our results corroborate that livestock grazing exerts important and direct benefits for plant species richness, which also benefits the diversity of other aboveground and belowground organisms (e.g., insects, worms, microorganisms) (see also Wang et al. 2019). ...
Article
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Pastoral systems face increasing pressure from competing global markets, food sector industrialization, and new policies such as Europe’s post-2020 Common Agriculture Policy. This pressure threatens the use of extensive sheep-grazing systems in mountain areas of low productivity but high natural value. Using information gathered at a long-term research setting in a mountainous area of the Basque Country (northern Spain), we assessed the multiple benefits of extensive dairy sheep grazing systems from multiple perspectives using indicators pertaining to ecological, socio-economic, and food quality domains. In this way, we address the benefits that would be lost if sheep grazing abandonment persists in mountain regions. Our results show that the benefits of extensive dairy sheep grazing in the research area include the production of healthy and high-quality foods and multiple ecological benefits including biodiversity conservation. Extensive dairy sheep grazing also contributes to rural development by generating employment and income in marginal, low-productivity lands that can support few economic alternatives. In particular, we found that sheep farmers who produce high-value products, such as cheese, have enhanced their economic profitability and are less dependent on public subsidies. However, careful attention to sustainable practices, support for new generations of farmers, and streamlined supply chains are required. These would contribute to ensure socio-economic benefits for farmers, avoid the ecological costs associated with grazing abandonment, and enhance ecosystem services for the whole society.
... Sí se usan en ciencia climática en general, en aspectos tan fundamentales como que el vapor de agua es, con mucho, el gas de mayor efecto invernadero -y afortunadamente, porque nuestro planeta de otro modo no sería habitable. Es necesario plantear qué escenarios de niveles de referencia debemos usar también para los impactos de la ganadería (Manzano & White 2019). Aquí África nos dice que el escenario natural contempla paisajes dominados por herbívoros, bien bisontes y cérvidos a la llegada de los europeos (Hristov 2012) o bien antes de que desaparecieran los megaherbívoros, en Norteamérica (Smith et al 2010) o en Siberia (Zimov & Zimov 2014). ...
Poster
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Los pastizales altoandinos cumplen un rol fundamental en el ciclo hidrológico y se constituyen en sumideros de carbono, un pastizal tipo Chilliwar captura 7.1 t C por ha año. Por otro lado, se ha estimado que la producción de metano entérico de las alpacas en pastoreo se aproxima a 8 kg CH4 por animal año. En esta situación aún es escasa la información que existe respecto a la huella de carbono de la producción alpaquera en sistemas de producción tradicionales y condiciones ambientales altoandinas. En el presente estudio se ha realizado un balance de CO2 para un sistema de producción de alpacas en pastoreo extensivo. Para ello se ha utilizado un caso de estudio en un pastizal altoandino “Chilliwar” de 50 has, con un hato de 100 alpacas madres con sus unidades acompañantes (machos reproductores, crías de 1 año, crías de 2 años y animales de reposición), manejado por una familia campesina. Los productos finales de este sistema son la fibra y la carne de alpaca. Se ha calculado la huella de carbono para los productos fibra y carne de alpaca. La única fuente de alimento para las alpacas es el propio pastizal, no existiendo insumos externos. Se ha estimado que, el pastizal altoandino captura 355 t de CO2 año, las alpacas consumen en forma de forraje 224 t de CO2 año. De otra parte, la población de alpacas, considerando las emisiones de CH4, emite 41.4 t de CO2-eq al año y la familia de pastores, por sus condiciones de vida y manejo tecnológico, conlleva una emisión 29.49 t de CO2-eq (mano de obra para actividades de pastoreo, esquila y otras actividades de sanidad y manejo ganadero). El balance anual del sistema estudiado es negativo (-60 t de CO2), resultando, la huella de carbono para los productos del sistema en -61.5 kg CO2-eq/kg de fibra y -22.3 kg CO2-eq/kg de carne. Por lo tanto, según los resultados de este caso de estudio, la crianza de alpacas en sistemas de producción tradicional en los andes puede considerarse un sumidero de carbono a corto y medio plazo. Este resultado presenta la posibilidad para mejorar el valor económico de la fibra y carne de alpaca en beneficio de las familias rurales alpaqueras.
... Sin embargo, también pueden ser empleados para calcular de manera más precisas las emisiones asociadas a la producción de materias primas para alimentación animal, que no ha sido posible incorporar al presente trabajo debido a que estos documentos se han terminado de publicar cuando el proyecto había finalizado. Este estudio más detallado de la producción ganadera también podría incluir análisis de niveles de base de emisiones 229,230 en ausencia de animales domésticos, para calcular emisiones de sistemas ganaderos vinculados al territorio en comparación con otros más intensivos. ...
Technical Report
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La “huella de carbono” expresa, en términos de CO2 equivalentes (CO2e), la cantidad de GEI emitida y carbono capturado en la elaboración de un producto o servicio. En este trabajo se ha estimado la huella de carbono del sistema agroalimentario y de la alimentación de la población residente en España, contabilizando de manera pormenorizada las emisiones de GEI que se generan no solo en campos de cultivo y granjas, sino también las que ocurren “aguas arriba” de la explotación, por ejemplo, durante la fabricación de los insumos agrícolas como fertilizantes y la producción de electricidad, o la producción de materias primas importadas para la producción de piensos (y deforestación asociada), así como de la gestión de residuos alimentarios. Para ello se ha empleado el Análisis de Ciclo de Vida (ACV), una metodología que, desde hace años, cuenta con un amplio respaldo dentro de la comunidad científica. Se consideran además 3 cortes temporales para el análisis de la evolución temporal de las emisiones del sistema agroalimentario en su conjunto: 1960, 1985 y 2010, mientras que en el caso de la producción de cultivos se estudian 4 cortes: 1900, 1960, 1990 y 2016.
... Other research has considered the effects of rewilding, the effect of moving away from pastoralism toward more dense production using concentrates and grain. When nonlivestock animals, such as nondomesticated ruminants and termites, move into areas previously used by livestock, there is a significant effect on GHGE (Manzano and White, 2019). As such, understanding what role dairy products, specifically, play in the US agricultural system and the nutritional and environmental impacts associated with removing dairy production would be of use in assessing dairy production's utility in the US food production system. ...
Article
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Questions regarding the balance between the contribution to human nutrition and the environmental impact of livestock food products rarely evaluate specific species or how to accomplish the recommended depopulation. The objective of this study was to assess current contributions of the US dairy industry to the supply of nutrients and environmental impact, characterize potential impacts of alternative land use for land previously used for crops for dairy cattle, and evaluate the impacts of these approaches on US dairy herd depopulation. We modeled 3 scenarios to reflect different sets of assumptions for how and why to remove dairy cattle from the US food production system coupled with 4 land-use strategies for the potential newly available land previously cropped for dairy feed. Scenarios also differed in assumptions of how to repurpose land previously used to grow grain for dairy cows. The current system provides sufficient fluid milk to meet the annual energy, protein, and calcium requirements of 71.2, 169, and 254 million people, respectively. Vitamins supplied by dairy products also make up a high proportion of total domestic supplies from foods, with dairy providing 39% of the vitamin A, 54% of the vitamin D, 47% of the riboflavin, 57% of the vitamin B12, and 29% of the choline available for human consumption in the United States. Retiring (maintaining animals without milk harvesting) dairy cattle under their current management resulted in no change in absolute greenhouse gas emissions (GHGE) relative to the current production system. Both depopulation and retirement to pasture resulted in modest reductions (6.8–12.0%) in GHGE relative to the current agricultural system. Most dairy cow removal scenarios reduced availability of essential micronutrients such as α-linolenic acid, Ca, and vitamins A, D, B12, and choline. Those removal scenarios that did not reduce micronutrient availability also did not improve GHGE relative to the current production system. These results suggest that removal of dairy cattle to reduce GHGE without reducing the supply of the most limiting nutrients to the population would be difficult.
... Sí se usan en ciencia climática en general, en aspectos tan fundamentales como que el vapor de agua es, con mucho, el gas de mayor efecto invernadero -y afortunadamente, porque nuestro planeta de otro modo no sería habitable. Es necesario plantear qué escenarios de niveles de referencia debemos usar también para los impactos de la ganadería (Manzano & White 2019). Aquí África nos dice que el escenario natural contempla paisajes dominados por herbívoros, bien bisontes y cérvidos a la llegada de los europeos (Hristov 2012) o bien antes de que desaparecieran los megaherbívoros, en Norteamérica (Smith et al 2010) o en Siberia (Zimov & Zimov 2014). ...
Conference Paper
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La alpaca (Vicugna pacos) es un mamífero artiodáctilo de la familia Camelidae. Digestivamente es considerado un pseudo-rumiante, produciendo metano durante el proceso digestivo. En el mundo existen alrededor de 4.1 millones de alpacas que son criadas para producir fibra la cual se considera de alta calidad. En el Perú se cría el 87% de la población mundial de alpacas. Su crianza se desarrolla en sistemas extensivos de pastoreo en pastizales altoandinos (>4000 msnm) a cargo de 82 mil familias rurales. La crianza de alpacas enfrenta bajos niveles de productividad y escaso desarrollo de capital y tecnología, como tal sus criadores se encuentran en condiciones de pobreza y pobreza extrema por los bajos precios de su fibra y carne. Los pastizales altoandinos cumplen un rol fundamental en el ciclo hidrológico y se constituyen en sumideros de carbono, un pastizal tipo Chilliwar captura 7.1 t C por ha año. Por otro lado, se ha estimado que la producción de metano entérico de las alpacas en pastoreo se aproxima a 8 kg CH4 por animal año. En esta situación aún es escasa la información que existe respecto a la huella de carbono de la producción alpaquera en sistemas de producción tradicionales y condiciones ambientales altoandinas. En el presente estudio se ha realizado un balance de CO2 para un sistema de producción de alpacas en pastoreo extensivo. Para ello se ha utilizado un caso de estudio en un pastizal altoandino “Chilliwar” de 50 has, con un hato de 100 alpacas madres con sus unidades acompañantes (machos reproductores, crías de 1 año, crías de 2 años y animales de reposición), manejado por una familia campesina. Los productos finales de este sistema son la fibra y la carne de alpaca. Se ha calculado la huella de carbono para los productos fibra y carne de alpaca. La única fuente de alimento para las alpacas es el propio pastizal, no existiendo insumos externos. Se ha estimado que, el pastizal altoandino captura 355 t de CO2 año, las alpacas consumen en forma de forraje 224 t de CO2 año. De otra parte, la población de alpacas, considerando las emisiones de CH4, emite 41.4 t de CO2-eq al año y la familia de pastores, por sus condiciones de vida y manejo tecnológico, conlleva una emisión 29.49 t de CO2-eq (mano de obra para actividades de pastoreo, esquila y otras actividades de sanidad y manejo ganadero). El balance anual del sistema estudiado es negativo (-60 t de CO2), resultando, la huella de carbono para los productos del sistema en -61.5 kg CO2-eq/kg de fibra y -22.3 kg CO2-eq/kg de carne. Por lo tanto, según los resultados de este caso de estudio, la crianza de alpacas en sistemas de producción tradicional en los andes puede considerarse un sumidero de carbono a corto y medio plazo. Este resultado presenta la posibilidad para mejorar el valor económico de la fibra y carne de alpaca en beneficio de las familias rurales alpaqueras.
... All ruminants produce methane and so have impacts on global warming, but in global assessments for climate change mitigation we are interested in those that are "additional." This means thinking about what the appropriate baseline is (Manzano & White, 2019). Emissions from industrial systems are clearly additional to a natural baseline. ...
Article
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The relationship between livestock production and climate change is the subject of hot debate, with arguments for major shifts in diets and a reduction in livestock production. This Perspective examines how global assessments of livestock‐derived methane emissions are framed, identifying assumptions and data gaps that influence standard life‐cycle analysis approaches. These include inadequate data due to a focus on industrial not extensive systems; errors arising due to inappropriate emission factors being applied; questions of how global warming potentials are derived for different greenhouse gases and debates about what baselines are appropriate. The article argues for a holistic systems approach that takes account of diverse livestock systems—both intensive and extensive—including both positive and negative impacts. In particular, the potential benefits of extensive livestock systems are highlighted, including supporting livelihoods, providing high‐quality nutrition, enhancing biodiversity, protecting landscapes, and sequestering carbon. By failing to differentiate between livestock systems, global assessments may mislead. Inappropriate measurement, verification and reporting processes linked to global climate change policy may in turn result in interventions that can undermine the livelihoods of extensive livestock‐keepers in marginal areas, including mobile pastoralists. In the politics of global assessments, certain interests promote framings of the livestock‐climate challenge in favour of contained, intensive systems, and the conversion of extensive rangelands into conservation investments. Emerging from a narrow, aggregated scientific framing, global assessments therefore can have political consequences. A more disaggregated, nuanced approach is required if the future of food and climate change is to be effectively addressed. This article is categorized under: Integrated Assessment of Climate Change > Assessing Climate Change in the Context of Other Issues Climate and Development > Social Justice and the Politics of Development
... Ces niveaux de référence sont utilisés en climatologie en général, dans des aspects si fondamentaux comme le niveau de vapeur d'eau (qui est de loin le gaz à effet de serre le plus important -et heureusement, car notre planète ne serait autrement pas habitable). Il est nécessaire d'examiner quelles options de niveaux de référence nous devrions utiliser également pour les impacts de l'élevage, et c'est ce que j'ai évoqué dans une publication récente (Manzano & White 2019). Ici, notre connaissance de l'Afrique nous explique que le modèle de paysage naturel est basé sur des paysages dominés par des herbivores, soit des bisons et des cervidés avant l'arrivée des Européens (Hristov 2012), soit des mégaherbivores, en Amérique du Nord (Smith et al 2010) ou en Sibérie (Zimov & Zimov 2014) avant leur disparition. ...
Article
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L'utilisation de niveaux de référence est courante dans les études scientifiques de disciplines diverses, y compris l'environnement, mais elles dépendent de la référence géographique ou historique considérée. La mesure des effets de l'élevage sur le changement climatique a toutefois négligé cet aspect. En effet, les émissions de gaz à effet de serre sont rarement considérées dans un contexte écologique. Les systèmes de ruminants nourris à l'herbe sont perçus comme de forts émetteurs de méthane, et, pour cette raison uniquement, il est peut-être recommandé de les convertir en systèmes intensifs de poulet et de porc nourris au grain. Nous avons examiné la littérature existante sur les émissions de gaz à effet de serre des ruminants sauvages, en tenant également compte du rôle potentiel des termites, susceptibles de remplacer les niches d'herbivores dans un scénario sans ongulés. Les scénarios de référence naturels seraient du même ordre de grandeur que les scénarios actuels d’élevage. Les recommandations politiques actuelles sur le changement dans le secteur de l'élevage risquent donc d'être beaucoup moins efficaces qu'on ne le pense actuellement. Des considérations similaires peuvent être appliquées sur les impacts de l'élevage sur l'eau ou la biodiversité. Les recommandations politiques devraient prendre en compte les niveaux de référence, se concentrer sur la réduction de l'utilisation intensive de combustibles fossiles et sur des stratégies de réduction du méthane ayant des bénéfices sociales, telles que l'utilisation de fourneaux de cuisson au biogaz alimentés au fumier.
... Arguments against red meat production rest on the assumption that if grazing ruminants are removed and the meat required is provided through intensive livestock systems (nonred meat), greenhouse gas (GHG) emissions will be reduced. However, the current paradigm for mitigating the effects of climate change by promoting intensive meat production from monogastric animals may be misleading [5]. In fact, in the absence of grazing by farmed ruminants, rangeland habitats may be dominated by other methane-producing herbivores including roe deer, elk, and reindeer. ...
Article
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Norway has vast rangeland resources (292,361 km2) with an estimated carrying capacity of nearly four million sheep and lambs, twice the current number. However, the intensive production system currently applied has led to more concentrate dependency, resulting in heavier animals in addition to poorer utilization of rangelands and homegrown feed. Intensive feeding systems indirectly influence the sustainability of ecosystems by promoting intensive cropping that can deplete soil fertility and threaten landscape preservation and biodiversity. By contrast, extensive grazing systems can produce environmentally and animal-friendly food products and contribute to regulating soil health, water and nutrient cycling, soil carbon sequestration, and recreational environments. In this paper, the economics of current sheep feeding practices in Norway, using a linear programming model, were compared with more extensive systems which allow for higher usage of on-farm feed resources. Changes in current sheep farming practices have the potential to increase lamb meat production relative to mutton production, in addition to improving the year-round supply of fresh meat. The investigated alternatives, using the Norwegian White Sheep (NWS) breed, suggest that delayed lambing is useful only on farms with abundant pastures available for autumn feeding. Lambs achieve a better market price than hoggets and mature sheep. Therefore, based on the current Norwegian meat market and price offered per kilogram of meat for lamb, an increase in NWS lamb production improves farm profits. On the other hand, when the aim is on greater use of homegrown feed and rangelands, this can be achieved through hogget production, and the quantity of concentrates required can be reduced substantially.
... Es cierto que la ganadería extensiva utiliza ciclos de vida más largos y que los animales, al moverse y estar en el exterior utilizan El argumento de la línea base de emisiones es muy interesante para la ganadería extensiva. Hay dos referencias clave para desarrollarlo, el artículo científico en el que Manzano y White exponen el fundamento de esta argumentación: Manzano & White (2019). Intensifying pastoralism may not reduce greenhouse gas emissions: wildlife-dominated landscape scenarios as a baseline in life-cycle analysis. ...
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Este cuaderno, coeditado por la Fundación Entretantos y la Plataforma por la Ganadería Extensiva y el Pastoralismo, recopila y organiza un intenso trabajo colectivo desarrollado en el seno de la Plataforma para abordar la adaptación y la lucha contra el cambio climático desde la perspectiva de la ganadería extensiva. El proceso se inició con una serie de debates en el seno de la Plataforma sobre el papel climático de la ganadería extensiva, sus emisiones, sus necesidades de adaptación y su potencial de mitigación. Estos debates fueron incorporando experiencias, artículos científicos (varios de ellos firmados por las mismas personas que debatían), prácticas innovadoras (planteadas desde la realidad de ganaderos y ganaderas en activo) y propuestas políticas que comparten una idea global: la necesidad de cambiar radicalmente, tanto a nivel técnico como científico y político, la visión actual de la relación entre cambio climático y ganadería extensiva. La riqueza de este debate y de las ideas aportadas nos animaron a presentarlas en la pasada reunión de la COP25, en Madrid. Esta presentación se organizó, de forma colaborativa, en torno a una mesa redonda en la que participaban, simultáneamente, personas vinculadas al mundo científico, investigadoras, activistas y, por supuesto, ganaderos y ganaderas. La fotografía de esta mesa redonda describe igualmente la forma de trabajo y el espíritu colectivo que constituyen la principal seña de identidad de la Plataforma. El paso siguiente consistía en transmitir estas ideas al resto de la sociedad, de forma que el cambio de perspectiva pudiera adoptarse de forma mucho más amplia, sobre todo entre las personas y organizaciones que trabajan alrededor de la ganadería, la agricultura y la alimentación. Así surge la iniciativa de editar y distribuir este cuaderno. El cuaderno organiza nuevas y viejas ideas, todas ellas con un sólido fundamento científico detrás. Se trata de un documento técnico, pero que se ha intentado hacer más comprensible y accesible a cualquier persona interesada, separando las ideas principales de una serie de materiales complementarios. Así, aunque el texto principal está escrito en tono divulgativo y accesible, el cuaderno incluye numerosos recuadros en los que se describen y enlazan artículos científicos, informes y documentos técnicos, en castellano o en inglés, que permiten fundamentar los contenidos y elaborar discursos propios. Sintetizando, se trata de desplegar la enorme capacidad que la ganadería extensiva tiene de cara a hacer más sostenible y segura nuestra producción de alimentos en el contexto actual de cambio climático, y también su aportación insustituible para adaptarnos y reducir los efectos de dicho cambio.
... For this reason, improving the efficiency in the use of this nutrient by ruminants may be a viable alternative not only to increase animal productivity but also to reduce GHG emissions by reducing N excretion. It must be noted however that in extensive grazing and pastoralist systems cattle can be undernourished, and the scarce nutrients can be used more effectively by animals (Manzano and White, 2019). ...
Article
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Cattle production systems are an important source of greenhouse gases (GHG) emitted to the atmosphere. Animal manure and managed soils are the most important sources of emissions from livestock after enteric methane. It is estimated that the N2O and CH4 produced in grasslands and manure management systems can contribute up to 25% of the emissions generated at the farm level, and therefore it is important to identify strategies to reduce the fluxes of these gases, especially in grazing systems where mitigation strategies have received less attention. This review describes the main factors that affect the emission of GHG from manure in bovine systems and the main strategies for their mitigation with emphasis on grazing production systems. The emissions of N2O and CH4 are highly variable and depend onmultiple factors, whichmakes it difficult to use strategies that mitigate both gases simultaneously. We found that strategies such as the optimization of the diet, the implementation of silvopastoral systems and other practices with the capacity to improve soil quality and cover, and the use of nitrogen fixing plants are among the practices with more potential to reduce emissions from manure and at the same time contribute to increase carbon capture and improve food production. These strategies can be implemented to reduce the emissions of both gases and, depending on the method used and the production system, the reductions can reach up to 50% of CH4 or N2O emissions from manure according to different studies. However, many research gaps should be addressed in order to obtain such reductions at a larger scale.
... Dans le contexte des changements globaux et d'incertitudes (catastrophes naturelles, zoonoses), le pastoralisme se positionne comme un système de production résilient et durable dans les systèmes socio-écologiques semi-arides (Leclerc et Sy, 2011 ;Manzano et White, 2019). Ce mode d'utilisation de l'espace est néanmoins sujet à plusieurs pressions et menaces, comme les changements climatiques (Simel, 2008 ;Hiernaux et al., 2014), la raréfaction des ressources fourragères (Traoré, 1997), le manque d'investissements publics dans l'accompagnement des systèmes pastoraux ou les politiques de gestion de l'espace minimisant la capacité de mouvement des troupeaux (Birch et Grahn, 2007), et les conflits avec d'autres modes d'utilisation de l'espace (Abbass, 2012 ;Butt et Turner, 2012 ;Butt, 2014). ...
Article
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In the context of global changes, pastoralism is positioned as a relevant production system in semi-arid areas. However, those ecosystems are particularly vulnerable face to global warming. It is now necessary to preserve them and think up flexible planning and management rules rooted in local socio-ecological realities. This article presents work carried out in the Ferlo (Sylvopastoral Zone), inhabited mainly by Fulani pastoralists. For more than half a century, the Ferlo has been the scene of constant development policies and projects accumulated around the management of pastoral resources and the fight against desertification. We defend the idea that difficulties in solving the socio-ecological challenges of the Ferlo come from project development implemented in this area are based on an obsolete narrative. Based on fieldwork and document analysis, we propose an update of this narrative, describing the socio-ecological transition of the Ferlo from the historical system of the hurum to a contemporary system characterized by great complexity. Throughout the article, we draw attention to the potential consequences of the discrepancy between the Ferlo as perceived by public authorities and development agents on the one hand and how Fulani pastoralists de facto use it.
... Dans le contexte des changements globaux et d'incertitudes (catastrophes naturelles, zoonoses), le pastoralisme se positionne comme un système de production résilient et durable dans les systèmes socio-écologiques semi-arides (Leclerc et Sy, 2011 ;Manzano et White, 2019). Ce mode d'utilisation de l'espace est néanmoins sujet à plusieurs pressions et menaces, comme les changements climatiques (Simel, 2008 ;Hiernaux et al., 2014), la raréfaction des ressources fourragères (Traoré, 1997), le manque d'investissements publics dans l'accompagnement des systèmes pastoraux ou les politiques de gestion de l'espace minimisant la capacité de mouvement des troupeaux (Birch et Grahn, 2007), et les conflits avec d'autres modes d'utilisation de l'espace (Abbass, 2012 ;Butt et Turner, 2012 ;Butt, 2014). ...
Article
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In the context of global changes, pastoralism is positioned as a relevant production system in semi-arid areas. However, those ecosystems are particularly vulnerable face to global warming. It is now necessary to preserve them and think up flexible planning and management rules rooted in local socio-ecological realities. This article presents work carried out in the Ferlo (Sylvopastoral Zone), inhabited mainly by Fulani pastoralists. For more than half a century, the Ferlo has been the scene of constant development policies and projects accumulated around the management of pastoral resources and the fight against desertification. We defend the idea that difficulties in solving the socio-ecological challenges of the Ferlo come from project development implemented in this area are based on an obsolete narrative. Based on fieldwork and document analysis, we propose an update of this narrative, describing the socio-ecological transition of the Ferlo from the historical system of the hurum to a contemporary system characterized by great complexity. Throughout the article, we draw attention to the potential consequences of the discrepancy between the Ferlo as perceived by public authorities and development agents on the one hand and how Fulani pastoralists de facto use it.
... It is important to generate truthful and objective information on the contribution of ruminant livestock systems to climate change. Although it is true that ruminants produce large amounts of methane from enteric fermentation -ruminants are blamed for 80% of the greenhouse gases emissions (GHG) in livestock systems-it is likewise true that grazing can increase carbon sequestration and compensate for emissions (Manzano & White, 2019). On the other hand, most publications related to GHG emissions from ruminants refer to feedlots where animals feed on cultivated grasslands, which is very different from the use of natural grazable resources produced in Mediterranean ecosystems with low use of non-renewable energy. ...
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Aim of study: To characterize and analyse the extensive livestock farming systems in environmental protected area and propose strategies for their sustainable improvement. Area of study: Sierra Nevada Protected Area (Spain) Material and methods: Data were collected from a sample of 85 farmers and 48 experts. The information from farmers was expressed in 35 variables, 23 of which were qualitative and 12 quantitative. A multivariate analysis was conducted. Main results: The principal components explained 71.2% of the total variance and the k-means cluster analysis identified three groups: C1 (38 farms), medium-size farms with a predominance of goats and relative dairy specialization; C2 (12 farms), large-size farms with extensive grazing lands, a high proportion of meat purpose animals and managed by young and dynamic farmers and C3 (35 farms), medium-size farms with a high proportion of meat purpose animals and undeveloped business management. The main problems reported were: insufficient pastures for livestock, stagnation of product prices, lack of generational renewal and need for social recognition of livestock farming. These obstacles could be overcome by implementing measures aimed at improving feed self-sufficiency -and thus reduce production costs- increasing income through social recognition of farming, achieving product differentiation, and strengthening short marketing channels. This would be favoured by an increase in associationism and specialized training. Research highlights: Farm management and marketing are important for improve these farming systems. The extensive livestock farming continues to be an important activity in European protected mountain areas.
... The most characteristic systems are the pastoral and agropastoral systems in arid and semiarid areas based on feed grazing accompanied by herd mobility (Neely et al., 2009). Several recent research studies have established the comparative advantage of these grazing livestock systems, notably in facing global environmental challenges related to methane emission and other greenhouse gas emissions (Vigne et al., 2013;Manzano and White, 2019) and carbon sequestration (Reid et al., 2004). Overall these systems are considered the most sustainable systems in these constrained and fragile environments, as shown by Behnke (1994), Th� ebaud and Batterbury (2001), and recently by Nori and Farinella (2021). ...
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Analyzing the sustainability of grazing livestock farming systems in the drylands at the farm and household or territorial levels (in terms of food security, well-being, value chain performance, feed supply, and maintenance of common grazing resources) constitutes a major challenge in the context of global changes. In particular, social–natural interdependency in an entanglement of spatial and temporal scales complicates the development of a common and systematic framework for assessing the sustainability of these grazing livestock systems. Our objective is to give an overview of some fundamental sets of indicators usually used and elaborate on some principles to guide the sustainable assessment of grazing livestock systems in drylands. To do so, this paper reviews a set of empirical, theoretical, and methodological studies related to the analysis of risk, adaptability, vulnerability, resilience, and sustainability of livestock systems in drylands based on grazing (mostly pastoral systems, but also some integrated crop-livestock systems). More concretely, this review seeks to compile a set of indicators to inform the processes of assessing the sustainability of livestock socio-ecosystems. It points to the wide range of approaches that have been used to address the sustainability of grazing livestock systems, ranging from those that focus on ecological or social approaches to more integrated and systemic approaches; from indicator-based approaches to those focusing on processes; from quantitative approaches to those that point out the need to take qualitative aspects into consideration; and from research-based assessments to participatory approaches. Based on this review, we propose a multi-scale indicators framework combining scales of space, time, and coordination to address the sustainability of these livestock systems. This framework aims to constitute a sound basis for elaborating a system of information that will contribute to and support policymakers and development agencies in developing their policies and measurements in order to ensure the sustainable development of pastoral and agropastoral systems in the short and medium-term. However, this study also warns about the multiple contextual scopes of the indicators and their implications, which reveal differing dynamics (and therefore adaptive capacities) of these systems.
... Similarly, the disagreement among experts on the contribution of grazing practices to carbon sequestration is consistent with previous studies that observed lower expert knowledge on carbon sequestration dynamics (Rodríguez-Ortega et al., 2018). Recent studies signal the potential of well-managed livestock systems to increase soil carbon storage capacity, but the effects of grazing intensity, regimes, season and species are still understudied (Stanley et al., 2018;Manzano and White, 2019). Likewise, the mismatches in the scoring according to the expert category and specialization claims for a broader transdisciplinary approach. ...
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Silvopastoral systems (SPS) emerge with a renewal interest in the Mediterranean for their promotion of multifunctionality through a variety of ecosystem services (ES). However, the understanding of how combined forestry and pastoral practices affect the ES delivery as well as the synergies and trade-off dynamics amongst them is still very limited. We applied the structured expert consultation Delphi method to assess the medium-term effect of relevant silvopastoral management practices (SMP) on the delivery of provision, regulation and maintenance and cultural ES in Mediterranean mid-mountain SPS in Spain. The deliberation process entailed two rounds and the Delphi panel was finally formed by 69 experts covering a broad spectrum of background and expertise. Results show that some practices, such as silvicultural treatments (e.g., thinning or coppice selection), play a multifunctional role contributing to ES delivery in bundles while some trade-offs are also identified between SMP, such as free animal grazing, and the provision of some ES. Synergies are also found between ES, such as livestock production and recreational hunting and between timber production and carbon sequestration, whereas possible trade-offs were particularly relevant between wildfire prevention and carbon sequestration. These findings can support decision-making processes towards sustainable and multifunctional silvopastoral management in the northern Mediterranean basin.
... Arguments against red meat production rest on the assumption that if grazing ruminants are removed and the meat required is provided through intensive livestock systems (nonred meat), greenhouse gas (GHG) emissions will be reduced. However, the current paradigm for mitigating the effects of climate change by promoting intensive meat production from monogastric animals may be misleading [5]. In fact, in the absence of grazing by farmed ruminants, rangeland habitats may be dominated by other methane-producing herbivores including roe deer, elk, and reindeer. ...
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Norway has vast rangeland resources (292,361 km2) with an estimated carrying capacity of nearly four million sheep and lambs, twice the current number. However, the intensive production system currently applied has led to more concentrate dependency, resulting in heavier animals in addition to poorer utilization of rangelands and homegrown feed. Intensive feeding systems indirectly influence the sustainability of ecosystems by promoting intensive cropping that can deplete soil fertility and threaten landscape preservation and biodiversity. By contrast, extensive grazing systems can produce environmentally and animal-friendly food products and contribute to regulating soil health, water and nutrient cycling, soil carbon sequestration, and recreational environments. In this paper, the economics of current sheep feeding practices in Norway, using a linear programming model, were compared with more extensive systems which allow for higher usage of on-farm feed resources. Changes in current sheep farming practices have the potential to increase lamb meat production relative to mutton production, in addition to improving the year-round supply of fresh meat. The investigated alternatives, using the Norwegian White Sheep (NWS) breed, suggest that delayed lambing is useful only on farms with abundant pastures available for autumn feeding. Lambs achieve a better market price than hoggets and mature sheep. Therefore, based on the current Norwegian meat market and price offered per kilogram of meat for lamb, an increase in NWS lamb production improves farm profits. On the other hand, when the aim is on greater use of homegrown feed and rangelands, this can be achieved through hogget production, and the quantity of concentrates required can be reduced substantially.
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Alternative systems for Norwegian sheep production: extending fresh meat season and meeting niche market demands Alternative system for norsk saueproduksjon: Utviding av fersk-kjøt-sesongen og fylling av marknadsnisjer Alternative systems for Norwegian sheep production: extending fresh meat season and meeting niche market demands Alternative system for norsk saueproduksjon: Utviding av fersk-kjøt-sesongen og fylling av marknadsnisjer Philosophiae Doctor (PhD) Thesis
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Livestock production systems in West Africa are fundamental for food security and for sustaining rural economies. A review of the environment, its distribution, genetics, production systems, inputs, animal health, outputs, trade, policies, roles and constraints drives to a series of recommendations for the future
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This report intends to address the role that extensive farming can play in the context of climate change, both in connection with improving the assessment of its emissions and their derived effects, as well as contributing to its adaptation, and above all, harnessing all its potential to fight climate change. This report is conceived as a technical guide to raise awareness on the main arguments that connect extensive farming to climate change, while providing access to abundant sources and reports. To this end, highlighted boxes appear interspersed in the text, referring to relevant technical or scientific publications related to the aspects addressed in each section.
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Exploring and developing new tools for the accounting and management of natural C sinks will provide a closer, more accurate option to remark the importance of such sinks in relation to livestock production, helping to support the persistence of some seriously endangered traditional, environmentally sustainable livestock farming. Following both precision and usability criteria, two main C sink databases covering the Andalusian region (S Spain) were developed from the Spanish Land Parcel Identification System (SIGPAC, coarse resolution) and the Spanish Information System on Land Cover (SIOSE, finer resolution) land use classes. Particular C sink factors based on growth rates for individual plant species were associated with detailed vegetation maps and, further, were linked to Land Use and Covers cartography across the region. In addition, eight ruminant farms were exhaustively studied in situ and used as a control. Results were compared with the obtained through the application of the developed C sink databases, and with the commonly used Petersen methodology. The sink capacity of vegetation associated with farms varied from 0.25 to 1.37 t CO2 ha−1 year−1, depending on the plant species composition and abundance. All the approaches showed significant differences from the control. C sink values were significantly higher when applying SIGPAC-based C sink database to farms, while values from the SIOSE and Petersen methodology approaches provided more moderate values, closer to the control. SIGPAC and Petersen approaches showed higher usability but presented lower precision due to a poor definition of plant cover. SIOSE-based C sink database provided suitable values able to be adapted to reality and used by farmers. In this regard, further research efforts to improve the adjustment of results and ease of use are required. The present approach means a methodological advance in the estimation of the C sink capacity associated with pastoral livestock farms, able to be incorporated into the CF calculation in contrasted areas worldwide, in the frame of the ‘eco-schemes’ being recently under development through the EU CAP.
Article
Sustainability discussions bring in multiple competing goals, and the outcomes are often conflicting depending upon which goal is being given credence. The role of livestock in supporting human well-being is especially contentious in discourses around sustainable diets. There is considerable variation in which environmental metrics are measured when describing sustainable diets, although some estimate of the greenhouse gas (GHG) emissions of different diets based on varying assumptions is commonplace. A market for animal-free and manufactured food items to substitute for animal source food (ASF) has emerged, driven by the high GHG emissions of ASF. Ingredients sourced from plants, and animal cells grown in culture are two approaches employed to produce alternative meats. These can be complemented with ingredients produced using synthetic biology. Alternative meat companies promise to reduce GHG, the land and water used for food production, and reduce or eliminate animal agriculture. Some CEOs have even claimed alternative meats will 'end world hunger'. Rarely do such self-proclamations emanate from scientists, but rather from companies in their efforts to attract venture capital investment and market share. Such declarations are reminiscent of the early days of the biotechnology industry. At that time, special interest groups employed fear-based tactics to effectively turn public opinion against the use of genetic engineering to introduce sustainability traits, like disease resistance and nutrient fortification, into global genetic improvement programs. These same groups have recently turned their sights on the 'unnaturalness' and use of synthetic biology in the production of meat alternatives, leaving agriculturists in a quandary. Much of the rationale behind alternative meats invokes a simplistic narrative, with a primary focus on GHG emissions, ignoring the nutritional attributes and dietary importance of ASF, and livelihoods that are supported by grazing ruminant production systems. Diets with low GHG emissions are often described as sustainable, even though the nutritional, social and economic pillars of sustainability are not considered. Nutritionists, geneticists, and veterinarians have been extremely successful at developing new technologies to reduce the environmental footprint of ASF. Further technological developments are going to be requisite to continuously improve the efficiency of animal source, plant source, and cultured meat production. Perhaps there is an opportunity to collectively communicate how innovations are enabling both alternative- and conventional-meat producers to more sustainably meet future demand. This could counteract the possibility that special interest groups who promulgate misinformation, fear and uncertainty, will hinder the adoption of technological innovations to the ultimate detriment of global food security.
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Animal source foods are evolutionarily appropriate foods for humans. It is therefore remarkable that they are now presented by some as unhealthy, unsustainable, and unethical, particularly in the urban West. The benefits of consuming them are nonetheless substantial, as they offer a wide spectrum of nutrients that are needed for cell and tissue development, function, and survival. They play a role in proper physical and cognitive development of infants, children, and adolescents, and help promote maintenance of physical function with ageing. While high-red meat consumption in the West is associated with several forms of chronic disease, these associations remain uncertain in other cultural contexts or when consumption is part of wholesome diets. Besides health concerns, there is also widespread anxiety about the environmental impacts of animal source foods. Although several production methods are detrimental (intensive cropping for feed, overgrazing, deforestation, water pollution, etc.) and require substantial mitigation, damaging impacts are not intrinsic to animal husbandry. When well-managed, livestock farming contributes to ecosystem management and soil health, while delivering high-quality foodstuffs through the upcycling of resources that are otherwise non-suitable for food production, making use of marginal land and inedible materials (forage, by-products, etc.), integrating livestock and crop farming where possible has the potential to benefit plant food production through enhanced nutrient recycling, while minimising external input needs such as fertilisers and pesticides. Moreover, the impacts on land use, water wastage, and greenhouse gas emissions are highly contextual, and their estimation is often erroneous due to a reductionist use of metrics. Similarly, whether animal husbandry is ethical or not depends on practical specificities, not on the fact that animals are involved. Such discussions also need to factor in that animal husbandry plays an important role in culture, societal well-being, food security, and the provision of livelihoods. We seize this opportunity to argue for less preconceived assumptions about alleged effects of animal source foods on the health of the planet and the humans and animals involved, for less top-down planning based on isolated metrics or (Western) technocratic perspectives, and for more holistic and circumstantial approaches to the food system.
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El pastoreo es un modelo de producción ganadera así como una forma de vida con importantes implicaciones sobre los territorios rurales a escala global. Sin embargo, el declive de los sistemas de explotación tradicionales y su conversión en formatos intensivos e industrializados ha abierto el debate sobre la sostenibilidad del sector ganadero. Por este motivo, las políticas públicas se han visto obligadas a elaborar estrategias y normativas que reconozcan los servicios prestados por el pastoreo extensivo, con medidas que apuestan por su protección y recuperación. En el presente texto se analiza el reconocimiento público del pastoreo en la Comunitat Valenciana, región admirativa que durante más de tres décadas ha reivindicado, en apariencia, la importancia de la ganadería extensiva en su acción política. Sin embargo, ante las limitaciones institucionales y burocráticas, en los últimos años emergen iniciativas que promueven enfoques nuevos y desconocidos en torno a la actividad pastoril, recuperando el anclaje territorial de los sistemas extensivos y tradicionales.
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Food's environmental impacts are created by millions of diverse producers. To identify solutions that are effective under this heterogeneity, we consolidated data covering five environmental indicators; 38,700 farms; and 1600 processors, packaging types, and retailers. Impact can vary 50-fold among producers of the same product, creating substantial mitigation opportunities. However, mitigation is complicated by trade-offs, multiple ways for producers to achieve low impacts, and interactions throughout the supply chain. Producers have limits on how far they can reduce impacts. Most strikingly, impacts of the lowest-impact animal products typically exceed those of vegetable substitutes, providing new evidence for the importance of dietary change. Cumulatively, our findings support an approach where producers monitor their own impacts, flexibly meet environmental targets by choosing from multiple practices, and communicate their impacts to consumers.
Technical Report
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In spite of negative perceptions, mobile pastoralism is a highly sustainable production system with clear environmental, social and economic benefits. This document makes the case for mobile pastoralism – a beneficial practice that is seriously threatened today, not just in the Mediterranean, but all over the world - through the revision of more than 100 scientific references.
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The extirpation of native wildlife species and widespread establishment of livestock farming has dramatically distorted large mammal herbivore communities across the globe. Ecological theory suggests that these shifts in the form and the intensity of herbivory have had substantial impacts on a range of ecosystem processes, but for most ecosystems it is impossible to quantify these changes accurately. We address these challenges using species-level biomass data from sub-Saharan Africa for both present day and reconstructed historical herbivore communities. Our analyses reveal pronounced herbivore biomass losses in wetter areas and substantial biomass increases and functional type turnover in arid regions. Fire prevalence is likely to have been altered over vast areas where grazer biomass has transitioned to above or below the threshold at which grass fuel reduction can suppress fire. Overall, shifts in the functional composition of herbivore communities promote an expansion of woody cover. Total herbivore methane emissions have more than doubled, but lateral nutrient diffusion capacity is below 5% of past levels. The release of fundamental ecological constraints on herbivore communities in arid regions appears to pose greater threats to ecosystem function than do biomass losses in mesic regions, where fire remains the major consumer.
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Organic agriculture is proposed as a promising approach to achieving sustainable food systems, but its feasibility is also contested. We use a food systems model that addresses agronomic characteristics of organic agriculture to analyze the role that organic agriculture could play in sustainable food systems. Here we show that a 100% conversion to organic agriculture needs more land than conventional agriculture but reduces N-surplus and pesticide use. However, in combination with reductions of food wastage and food-competing feed from arable land, with correspondingly reduced production and consumption of animal products, land use under organic agriculture remains below the reference scenario. Other indicators such as greenhouse gas emissions also improve, but adequate nitrogen supply is challenging. Besides focusing on production, sustainable food systems need to address waste, crop–grass–livestock interdependencies and human consumption. None of the corresponding strategies needs full implementation and their combined partial implementation delivers a more sustainable food future.
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The report dissects claims made by different stakeholders in the debate about so called ‘grass-fed’ beef, the greenhouse gases the animals emit, and the possibility that, through their grazing actions, they can help remove carbon dioxide from the atmosphere. It evaluates these claims and counterclaims against the best available science, providing an authoritative and evidence-based answer to the question: Is grass-fed beef good or bad for the climate?
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Background: Livestock play an important role in carbon cycling through consumption of biomass and emissions of methane. Recent research suggests that existing bottom-up inventories of livestock methane emissions in the US, such as those made using 2006 IPCC Tier 1 livestock emissions factors, are too low. This may be due to outdated information used to develop these emissions factors. In this study, we update information for cattle and swine by region, based on reported recent changes in animal body mass, feed quality and quantity, milk productivity, and management of animals and manure. We then use this updated information to calculate new livestock methane emissions factors for enteric fermentation in cattle, and for manure management in cattle and swine. Results: Using the new emissions factors, we estimate global livestock emissions of 119.1 ± 18.2 Tg methane in 2011; this quantity is 11% greater than that obtained using the IPCC 2006 emissions factors, encompassing an 8.4% increase in enteric fermentation methane, a 36.7% increase in manure management methane, and notable variability among regions and sources. For example, revised manure management methane emissions for 2011 in the US increased by 71.8%. For years through 2013, we present (a) annual livestock methane emissions, (b) complete annual livestock carbon budgets, including carbon dioxide emissions, and (c) spatial distributions of livestock methane and other carbon fluxes, downscaled to 0.05 × 0.05 degree resolution. Conclusions: Our revised bottom-up estimates of global livestock methane emissions are comparable to recently reported top-down global estimates for recent years, and account for a significant part of the increase in annual methane emissions since 2007. Our results suggest that livestock methane emissions, while not the dominant overall source of global methane emissions, may be a major contributor to the observed annual emissions increases over the 2000s to 2010s. Differences at regional and local scales may help distinguish livestock methane emissions from those of other sectors in future top-down studies. The revised estimates allow improved reconciliation of top-down and bottom-up estimates of methane emissions, will facilitate the development and evaluation of Earth system models, and provide consistent regional and global Tier 1 estimates for environmental assessments.
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Defining rangelands as anthromes enabled Ellis and Ramankutty (2008) to conclude that more than three-quarters of Earth's land is anthropogenic; without rangelands, this figure would have been less than half. They classified all lands grazed by domestic livestock as rangelands, provided that human population densities were low; similar areas without livestock were excluded and classified instead as 'wildlands'. This paper examines the empirical basis and conceptual assumptions of defining and categorizing rangelands in this fashion. Empirically, we conclude that a large proportion of rangelands, although used to varying degrees by domesticated livestock, are not altered significantly by this use, especially in arid, highly variable environments and in settings with long evolutionary histories of herbivory by wild animals. Even where changes have occurred, the dynamics and components of many rangelands remain structurally and functionally equivalent to those that preceded domestic livestock grazing or would be found in its absence. In much of Africa and Asia, grazing is so longstanding as to be inextricable from 'natural' or reference conditions for those sites. Thus, the extent of anthropogenic biomes is significantly overstated. Conceptually, rangelands reveal the dependence of the anthromes thesis on outdated assumptions of ecological climax and equilibrium. Coming to terms with rangelands-how they can be classified, understood, and managed sustainably-thus offers important lessons for understanding anthromes and the Anthropocene as a whole. At the root of these lessons, we argue, is not the question of human impacts on ecosystems but property relations among humans.
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Open-burning of rice straw residues pollutes the air and contributes to global warming through emissions of greenhouse gases (GHGs). Although burning of straw residues emits large amounts of CO2 , this component of the smoke is not considered as net GHG emissions and only concludes the annual carbon cycle that has started with photosynthesis. Hence, we focused on emissions of CH4 and N2O from open-field burning against a baseline of straw incorporation. The experimental approach combined a newly designed combustion chamber for the collection of smoke followed by chemical analysis (Exp. A) as well as field observations of soil-borne emissions for different straw treatments (Exp. B). At constant straw moisture of 10%, the mass-scaled Emission Factors (EF m) were 4.51 g CH 4 and 0.069 g N2O per kg dry weight (kg-1 dw) of straw. In Exp. B, we conducted field trials over two seasons with the following straw management practices: SRt - straw retained including stubbles and incorporated, PSRm - partial straw removal only stubbles incorporated, CSRm - complete straw removal including removal of stubbles, and SB - straw burned followed by incorporation of ash and unburned residues. Soil-borne emissions were recorded with a closed chamber approach whereas straw burning was computed indirectly using the EF from Exp. A. As metrics for comparison, we have used the GWP contributions of CH 4 and N 2 O for the different straw management practices over two cropping seasons in the field. On an annual basis, SRt had the highest total GWP (8023 kg CO2eq ha-1). SB entailed a GWP of 4913 kg CO2eq ha-1 that was almost identical to the GWP of PSRm (4531 kg CO2eq ha-1). CSRm had the lowest GWP (3470 kg CO2eq ha-1) that was significantly lower than that of SRt. However, full GHG accounting of straw removed from the field will depend on the ensuing utilization of straw and the off-field emissions involved - which was outside of the boundaries of this study. The quantification of open field burning in this study can be instrumental for diverse purposes by providing data of an important component in emission inventories and carbon footprint analysis of rice.
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Wood-pastures are archetypes of High Nature Value Farmlands in Europe and hold exceptional ecological, social, and cultural values. Yet, wood-pastures have been through a sharp decline all over Europe, mainly due to processes of agricultural intensification and abandonment. Recently, wood-pastures have found increasing attention from conservation science and policy across Europe. In this paper we (i) perform the first pan-European assessment of wood-pastures, considering individual countries and biogeographic regions, (ii) present the ecological and social–cultural values of a wide diversity of wood-pasture systems in Europe, (iii) outline management challenges around wood-pastures, and (iv) provide insights for the policy agenda targeting wood-pastures in Europe. We estimate that wood-pastures cover an area of approximately 203,000 km2 in the European Union (EU). They are distributed across all biogeographical regions, but more abundantly in the Mediterranean and Eastern European countries. Substantial ecological values are revealed in terms of landscape level biodiversity, ecosystem dynamics, and genetic resources. Social–cultural values are related to aesthetic values, cultural heritage, and rich traditional ecological knowledge. We discuss the anthropogenic character of wood-pastures, requiring multifunctional land management, which is a major conservation challenge. Despite increasing societal appreciation of wood-pastures, their integration into effective agricultural and conservation policies has proved to be complicated, because institutional structures are traditionally organized within mono-functional sectors. We offer suggestions as to how these shortcomings might be overcome in the Common Agricultural Policy, including Rural Development policy, and the Habitats Directive of the EU. We conclude that research should be guided by a holistic vision of wood-pastures, which integrates information about ecology, societal values, and institutional arrangements.
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Methane is an important greenhouse gas but characterizing production by source sector has proven difficult. Current estimates suggest herbivores produce ~20% (~76-189 Tg yr(-1) ) of methane globally, with wildlife contributions uncertain. We develop a simple and accurate method to estimate methane emissions and reevaluate production by wildlife. We find a strikingly robust relationship between body mass and methane output exceeding the scaling expected by differences in metabolic rate. Our allometric model gives a significantly better fit to empirical data than IPCC Tier 1 and 2 calculations. Our analysis suggests that: a) the allometric model provides an easier and more robust estimate of methane production than IPCC models currently in use, b) output from wildlife is much higher than previously considered, and c) because of the sublinear allometric scaling of methane output with body mass, national emissions could be reduced if countries favored more, smaller livestock, over fewer, larger ones. This article is protected by copyright. All rights reserved. This article is protected by copyright. All rights reserved.
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The ‘sustainable intensification’ (SI) approach and ‘climate-smart agriculture’ (CSA) are highly complementary. SI is an essential means of adapting to climate change, also resulting in lower emissions per unit of output. With its emphasis on improving risk management, information flows and local institutions to support adaptive capacity, CSA provides the foundations for incentivizing and enabling intensification. But adaptation requires going beyond a narrow intensification lens to include diversified farming systems, local adaptation planning, building responsive governance systems, enhancing leadership skills, and building asset diversity. While SI and CSA are crucial for global food and nutritional security, they are only part of a multi-pronged approach, that includes reducing consumption and waste, building social safety nets, facilitating trade, and enhancing diets.
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Modern wetlands are the world's strongest methane source. But what was the role of this source in the past? An analysis of global 14C data for basal peat combined with modelling of wetland succession allowed us to reconstruct the dynamics of global wetland methane emission through time. These data show that the rise of atmospheric methane concentrations during the Pleistocene-Holocene transition was not connected with wetland expansion, but rather started substantially later, only 9 thousand years ago. Additionally, wetland expansion took place against the background of a decline in atmospheric methane concentration. The isotopic composition of methane varies according to source. Owing to ice sheet drilling programs past dynamics of atmospheric methane isotopic composition is now known. For example over the course of Pleistocene-Holocene transition atmospheric methane became depleted in the deuterium isotope, which indicated that the rise in methane concentrations was not connected with activation of the deuterium-rich gas clathrates. Modelling of the budget of the atmospheric methane and its isotopic composition allowed us to reconstruct the dynamics of all main methane sources. For the late Pleistocene, the largest methane source was megaherbivores, whose total biomass is estimated to have exceeded that of present-day humans and domestic animals. This corresponds with our independent estimates of herbivore density on the pastures of the late Pleistocene based on herbivore skeleton density in the permafrost. During deglaciation, the largest methane emissions originated from degrading frozen soils of the mammoth steppe biome. Methane from this source is unique, as it is depleted of all isotopes. We estimated that over the entire course of deglaciation (15,000 to 6,000 year before present), soils of the mammoth steppe released 300-550 Pg (1015 g) of methane. From current study we conclude that the Late Quaternary Extinction significantly affected the global methane cycle.
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Livestock are responsible for 12% of anthropogenic greenhouse gas emissions. Sustainable intensification of livestock production systems might become a key climate mitigation technology. However, livestock production systems vary substantially, making the implementation of climate mitigation policies a formidable challenge. Here, we provide results from an economic model using a detailed and high-resolution representation of livestock production systems. We project that by 2030 autonomous transitions toward more efficient systems would decrease emissions by 736 million metric tons of carbon dioxide equivalent per year (MtCO2e⋅y(-1)), mainly through avoided emissions from the conversion of 162 Mha of natural land. A moderate mitigation policy targeting emissions from both the agricultural and land-use change sectors with a carbon price of US$10 per tCO2e could lead to an abatement of 3,223 MtCO2e⋅y(-1). Livestock system transitions would contribute 21% of the total abatement, intra- and interregional relocation of livestock production another 40%, and all other mechanisms would add 39%. A comparable abatement of 3,068 MtCO2e⋅y(-1) could be achieved also with a policy targeting only emissions from land-use change. Stringent climate policies might lead to reductions in food availability of up to 200 kcal per capita per day globally. We find that mitigation policies targeting emissions from land-use change are 5 to 10 times more efficient-measured in "total abatement calorie cost"-than policies targeting emissions from livestock only. Thus, fostering transitions toward more productive livestock production systems in combination with climate policies targeting the land-use change appears to be the most efficient lever to deliver desirable climate and food availability outcomes.
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Fodder trees are important feed sources for livestock in a wide range of farming systems in Africa. Researchers, extension services and farmers have developed and promoted fodder tree practices in many different countries and contexts. Fodder trees are particularly important in the highlands of Eastern Africa, where over 200 000 smallholders plant them, mainly to feed dairy cows. They can meet production shortages in times of extreme climatic conditions such as droughts. Fodder trees are easy to grow, require little land, labor or capital, have numerous by-products and often supply feed within a year after planting. Key challenges constraining the uptake of fodder trees include limited species appropriate to different agro-ecological zones, shortages in seed and that farmers lack knowledge and skills needed to grow them.
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Estimates of global greenhouse gases (GHG) emissions attributable to livestock range from 8 to 51%. This variability creates confusion among policy makers and the public as it suggests that there is a lack of consensus among scientists with regard to the contribution of livestock to global GHG emissions. In reality, estimates of international scientific organizations such as the International Governmental Panel on Climate Change (IPCC) and the Food and Agriculture Organization (FAO) are in close agreement, with variation mainly arising on how GHG emissions are allocated to land use and land use change. Other estimates involve major deviations from international protocols, such as estimated global warming potential of CH4 or including respired CO2 in GHG emissions. These approaches also fail to differentiate short-term CO2 arising from oxidation of plant C by ruminants from CO2 released from fixed fossil C through combustion. These deviances from internationally accepted protocols create confusion and direct attention from anthropomorphic practices which have the most important contribution to global GHG emissions. Global estimates of livestock GHG emissions are most reliable when they are generated by internationally recognized scientific panels with expertise across a range of disciplines, and with no preconceived bias to particular outcomes.This paper is part of the special issue entitled: Greenhouse Gases in Animal Agriculture – Finding a Balance between Food and Emissions, Guest Edited by T.A. McAllister, Section Guest Editors; K.A. Beauchemin, X. Hao, S. McGinn and Editor for Animal Feed Science and Technology, P.H. Robinson.
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In this chapter we argue that in order to substantially reduce greenhouse gas (GHG) emissions from food production and to preserve natural and agricultural biodiversity, policies that separately address the demand and the supply sides of the food system will be required. Taxes on animal food, and other policies that shift consumption patterns towards less GHG intensive and land-demanding food, will be crucial for reducing agricultural GHG emissions as well as for mitigating biodiversity losses related to the expansion of agriculture into natural ecosystems. Demand-moderating policies are vital because of the overall low potential for reducing agricultural GHG emissions by technological means, and because of the inherently large land requirements of ruminant meat (beef and lamb) production. However, demand-side policies alone are far from enough. Comprehensive supply-side policies will also be required, especially for containing agricultural land expansion in order to protect biodiversity in tropical regions. Supply-side policies, such as direct subsidies, will also be fundamental for preserving agricultural-related biodiversity in Europe and other regions holding biodiversity-rich permanent pastures. The latter holds for Europe even if no policies that moderate the demand for ruminant meat are put in place, since the low-intensive land use characteristic of these areas in either case is not economically viable in the long run. Furthermore, the biodiversity rich areas represent a minor share of the total agricultural land in Europe. Therefore, the goal to preserve agricultural biodiversity in Europe should not be taken as a counter-argument against reducing global ruminant meat production by the implementation of demand-moderating policies.
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Termites may emit large quantities of methane, carbon dioxide, and molecular hydrogen into the atmosphere. Global annual emissions calculated from laboratory measurements could reach 1.5 x 10(14) grams of methane and 5 x 10(16) grams of carbon dioxide. As much as 2 x 10(14) grams of molecular hydrogen may also be produced. Field measurements of methane emissions from two termite nests in Guatemala corroborated the laboratory results. The largest emissions should occur in tropical areas disturbed by human activities.
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The loss of megafauna at the terminal Pleistocene has been linked to a wide range of Earth-system-level changes, such as altered greenhouse gas budgets, fire regimes and biome-level vegetation changes. Given these influences and feedbacks, might part of the solution for mitigating anthropogenic climate change lie in the restoration of extant megafauna to ecosystems? Here, we explore the potential role of trophic rewilding on Earth's climate system. We first provide a novel synthesis of the various ways that megafauna interact with the major drivers of anthropogenic climate change, including greenhouse gas storage and emission, aerosols and albedo. We then explore the role of rewilding as a mitigation tool at two scales: (i) current and near-future opportunities for national or regional climate change mitigation portfolios, and (ii) more radical opportunities at the global scale. Finally, we identify major knowledge gaps that complicate the complete characterization of rewilding as a climate change mitigation strategy. Our perspective is urgent since we are losing the Earth's last remaining megafauna, and with it a potential option to address climate change. This article is part of the theme issue ‘Trophic rewilding: consequences for ecosystems under global change’.
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This chapter “Wildlife in the Exclusion Zone in Chernobyl” explores the state of wildlife in Chernobyl three decades after the nuclear disaster, as a comparative reference for the wildlife in Fukushima in the near future. Wildlife appears to be thriving in Chernobyl, which is evidenced by the rebound of the population of gray wolves that are the top predators in the area. However, scientific studies of the population thus far are inconclusive regarding the effects of low-level, long-term radiation on their health. The wildlife in Chernobyl also gives insight into the possibility of rewilding projects in Fukushima and elsewhere.
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As a major contributor to agricultural greenhouse gas (GHG) emissions, it has been suggested that reducing animal agriculture or consumption of animal-derived foods may reduce GHGs and enhance food security. Because the total removal of animals provides the extreme boundary to potential mitigation options and requires the fewest assumptions to model, the yearly nutritional and GHG impacts of eliminating animals from US agriculture were quantified. Animal-derived foods currently provide energy (24% of total), protein (48%), essential fatty acids (23-100%), and essential amino acids (34-67%) available for human consumption in the United States. The US livestock industry employs 1.6 × 10(6) people and accounts for $31.8 billion in exports. Livestock recycle more than 43.2 × 10(9) kg of human-inedible food and fiber processing byproducts, converting them into human-edible food, pet food, industrial products, and 4 × 10(9) kg of N fertilizer. Although modeled plants-only agriculture produced 23% more food, it met fewer of the US population's requirements for essential nutrients. When nutritional adequacy was evaluated by using least-cost diets produced from foods available, more nutrient deficiencies, a greater excess of energy, and a need to consume a greater amount of food solids were encountered in plants-only diets. In the simulated system with no animals, estimated agricultural GHG decreased (28%), but did not fully counterbalance the animal contribution of GHG (49% in this model). This assessment suggests that removing animals from US agriculture would reduce agricultural GHG emissions, but would also create a food supply incapable of supporting the US population's nutritional requirements.
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Despite growing popularity rewilding has yet to make significant inroads within the conservation mainstream which currently embraces the biodiversity and economic narratives; some ecologists dismiss it as being little more than a rebranding of ecosystem rehabilitation. If it is to gain greater influence over policy and planning, rewilding will need to showcase the unique contribution of wild values to society and demonstrate how they may be integrated with other conservation narratives. In this perspective, I frame a wild revival strategy in four interrelated questions: What do we mean by the wild? Why should humans pursue wild-life conservation? If they do, what pathways to the wild may be pursued? What kinds of outcomes result from different conservation strategies? In answering these questions, eight strategic pathways are presented which elucidate both the wild values of nature and different ways in which the wild can be enhanced, ranging from rehabilitation of vermin to ecosystem restoration. Wild ecosystems are more dynamic with greater biological expression; dewilded ones are either degraded or, paradoxically, more highly managed. The pathways provide a framework for resolving conflicts between multiple conservation narratives by facilitating agreement at the level of specific conservation actions.
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As the burger hits the pan, it sizzles. A familiar smoky aroma fills the air. The first bite reveals a juicy pink centre. But this is no ordinary hamburger. It's formed entirely from plants and was made to mimic a burger in every way by scientists in California's Silicon Valley. "Meat is really delicious stuff, but it's created by a very inefficient process," says Chris Davis, the biotechnologist who leads research and development at Impossible Foods in Redwood City-the company behind the Impossible Burger. "And in the last 40-50 years it's gone from something that's eaten on special occasions to something that's eaten all tha time. © 2017 Macmillan Publishers Limited, part of Springer Nature. All rights reserved.
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Pastoralist systems are complex production systems able to thrive in areas with scarce and unpredictable plant productivity. However, they have been negatively impacted by poorly designed development interventions and negative media portrayals. Investment guided by careful understanding and consultation with local communities can take advantage of improvement in technologies and markets to achieve a fairer and balanced improvement in pastoralist livelihoods. Read-only version available at http://rdcu.be/pAqc
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Cattle production is characterized by high land requirements, and greenhouse gas (GHG) emissions associated with the resulting land use change (LUC) and cradle to farm gate processes. Intensification of cattle production systems is considered an important strategy for mitigating anthropogenic GHG emissions. When categorizing production practices into three systems, i.e. pasture-based, mixed and industrial systems, intensification can either take place within one system or through the transition to another more productive system. This study investigates the impacts of these two pathways on farm gate emissions and LUC-related emissions (expressed in kg CO2-eq per kg of milk or beef) in nine world regions. First, a review is conducted of bottom-up studies on farm gate emissions (without LUC) from dairy production in Europe and beef production in North America and Brazil. Then, a global data set on GHG emissions from cattle production is used to discuss the GHG emission impacts of the two development pathways in other regions. Finally, the GLOBIOM model is applied to perform a global assessment of land occupation and LUC-related emissions. For dairy in Europe, farm gate emission reductions of 1%–14% are found for intensification within one system and 2%–26% for system transitions. In Europe as well as other developed regions, the comparative influence of both pathways on the GHG balance largely depends on the specific design of the initial and final production systems. In developing countries especially, there is a greater potential for emission reductions through intensification within the pasture-based system. The additional reduction potential of moving from pasture-based to mixed and industrial production is limited. Also, emission reductions of intensification within the mixed system are smaller compared to the pasture-based system. For beef production in Brazil, intensification within pasture-based systems can attain significant farm gate emission reductions (>50%). The same is true for pasture-based systems in other developing regions and also some developed regions. Furthermore, the additional GHG reduction potentials of moving from pasture-based to mixed systems, and of intensification within mixed systems are larger for beef than for dairy. Although both the dairy and beef sector can often attain significant farm gate emission reductions through intensification within pasture-based systems, the transition to mixed systems is important to reduce land occupation and LUC-related emissions. LUC mitigation is considered to be the most important GHG mitigation strategy for cattle production in Sub-Saharan Africa and Latin America. Important, but technically and economically constrained strategies to reduce both farm gate and LUC-related emissions include increasing the productivity of grassland and cropland, and increasing the animal productivity through improved feed quality.
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Greenhouse gas (GHG) emission measurements from livestock excreta in Africa are limited. We measured CH4 and N2O emissions from excreta of six Boran (Bos indicus) and six Friesian (Bos taurus) steers near Nairobi, Kenya. The steers were fed one of three diets (T1 [chaffed wheat straw], T2 [T1 + Calliandra calothyrsus Meissner - 0.2% live weight per day], and T3 [T1 + calliandra - 0.4% live weight every 2 d]). The T1 diet is similar in quality to typical diets in the region. Calliandra is a leguminous fodder tree promoted as a feed supplement. Fresh feces and urine were applied to grasslands and emissions measured using static chambers. Cumulative 28-d fecal emissions were 302 ± 52.4 and 95 ± 13.8 mg CH4-C kg⁻¹ dry matter for Friesen and Boran steers, respectively, and 11.5 ± 4.26 and 24.7 ± 8.32 mg N2O-N kg⁻¹ dry matter for Friesian and Boran steers, respectively. For urine from Friesian steers, the N2O emissions were 2.8 ± 0.64 mg N2O-N 100 mL urine⁻¹. The CH4 emission factors (EFs) (246 ± 49.5 and 87 ± 12.7 g CH4-C yr⁻¹ animal⁻¹ for Friesan and Boran, respectively) were lower than the International Panel on Climate Change EFs (750 g CH4-C animal⁻¹ yr⁻¹), whereas the N2O EFs (0.1 and 0.2% for the Friesian and Boran feces, respectively, and 1.2% for urine) were also lower than International Panel on Climate Change estimates. The low N content of the excreta likely caused the low emissions and indicates that current models probably overestimate CH4 and N2O emissions from African livestock manure. © American Society of Agronomy, Crop Science Society of America, and Soil Science Society of America. 5585 Guilford Rd., Madison, WI 53711 USA. All rights reserved.
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The livestock sector supports about 1.3 billion producers and retailers, and contributes 40-50% of agricultural GDP. We estimated that between 1995 and 2005, the livestock sector was responsible for greenhouse gas emissions of 5.6-7.5 GtCO2 e yr â'1. Livestock accounts for up to half of the technical mitigation potential of the agriculture, forestry and land-use sectors, through management options that sustainably intensify livestock production, promote carbon sequestration in rangelands and reduce emissions from manures, and through reductions in the demand for livestock products. The economic potential of these management alternatives is less than 10% of what is technically possible because of adoption constraints, costs and numerous trade-offs. The mitigation potential of reductions in livestock product consumption is large, but their economic potential is unknown at present. More research and investment are needed to increase the affordability and adoption of mitigation practices, to moderate consumption of livestock products where appropriate, and to avoid negative impacts on livelihoods, economic activities and the environment.
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The increasing abandonment of marginal land creates new opportunities for restoration, reintroduction, and rewilding, but what do these terms mean in a rapidly and irreversibly changing world? The ‘re’ prefix means ‘back’, but it is becoming clear that the traditional use of past ecosystems as targets and criteria for success must be replaced by an orientation towards an uncertain future. Current opinions in restoration and reintroduction biology range from a defense of traditional definitions, with some modifications, to acceptance of more radical responses, including assisted migration, taxon substitution, de-extinction, and genetic modification. Rewilding attempts to minimize sustained intervention, but this hands-off approach is also threatened by rapid environmental change.
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Excerpt Climate change negotiations at the 21st Conference of the Parties to the United Nations (UN) Framework Convention on Climate Change (COP21) in Paris (November 30 to December 11, 2015) were unique because soil carbon (C) and agriculture were on the agenda for the first time ever since COP meetings started 21 years ago. The “4 per Thousand” proposal calls for a voluntary action plan to enhance soil organic carbon (SOC) content of world soils to a 40 cm (16 in) depth at the rate of 0.4% per year. The strategy is to promote SOC sequestration through adoption of recommended management practices (RMPs) of C farming including conservation agriculture (CA), mulch farming, cover cropping, agroforestry, biochar, improved grazing, and restoration of degraded soils through soil-landscape restoration, etc. Theoretically, the world's cropland soils could sequester as much as 62 t ha⁻¹ (25 tn ac⁻¹) over the next 50 to 75 years (0.8 to 1.2 t ha⁻¹ y⁻¹ [0.3 to 0.5 tn ac⁻¹ yr⁻¹]) with a total C sink capacity of ~88 Gt (~97 billion tn) on 1,400 Mha (3,500 million ac). In addition, there is also SOC sequestration potential of grazing lands, forest lands, and degraded and desertified lands. With global implementation,…
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Sustainability as dietary guidance created political debate.
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The purpose of this study was to conduct a comprehensive systematic review to identify feed additives, listed on Annex 1 of the European Union Register of Feed Additives, that have potential to reduce polluting emissions from livestock and to conduct a very simple meta-analysis of the collated data in order to identity the potential efficacy of these substances and agents. This study differs from the many other meta-analyses published in this general area in that it encompasses a broader range of environmental impacts and animal species within a single study than has occurred heretofore. The review identified 37 substances and agents offering benefits for 6 different potentially polluting emissions: gaseous releases of ammonia, methane, carbon dioxide, odours, and excretion of nitrogen and phosphorus for four animal groups: cattle, sheep, pigs and poultry. The meta-analysis showed that very considerable reductions in these emissions may be achievable, particularly in respect to ammonia and greenhouse gases. Estimates based on modest levels of usage in the European Union suggest that a reduction greater than 168 kt ammonia and 7100 kt methane could be achievable. However, in order to maximize these benefits regulators and the wider industry need to implement policies, processes and incentives to encourage greater uptake.
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Achieving food system sustainability is a global priority but there are different views on how it might be achieved. Broadly three perspectives are emerging, defined here as: efficiency oriented, demand restraint and food system transformation. These reflect different conceptualisations on what is practically achievable, and what is desirable, underpinned by different values and ideologies about the role of technology, our relationship with nature and fundamentally what is meant by a ‘good life.’ This paper describes these emerging perspectives and explores their underlying values; highlights LCA's role in shaping these perspectives; and considers how LCA could be oriented to clarify thinking and advance policy-relevant knowledge. It argues that more work is needed to understand the values underlying different approaches to the food sustainability problem. This can shed light on why stakeholders disagree, where there are genuine misunderstandings, and where common ground is possible and ways forward agreed.
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Agricultural land and food security are under pressure from climate change, population growth, urbanisation, and demand for biofuels and animal protein. We have re-assessed the role of ruminant livestock in meeting food requirements in the context of mixed agricultural systems, and focussed on seven major challenges: • Poor animal health and welfare. • Consumption of human food by livestock. • Environmental footprint. • Livestock species and genotypes adapted to the local environment. • Focus on healthy food. • Feed the animals correctly. • Livestock husbandry and management. Theses issues are intended to guide research, and stimulate discussion and international collaboration. The challenges are multidisciplinary, so solutions can only be identified and demonstrated in real-world production systems. We propose the establishment of a network of ‘farm platforms', across different climatic and eco-regions, such as the University of Western Australia Future Farm, Thiruvazhankunnu Livestock Research Station, and the Rothamsted Research North Wyke Farm Platform.
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Different tillage systems result in different resource uses and environmental impacts. Reduced tillage generates savings in direct energy input and the amount of machinery items needed. As the basics for holistic Life Cycle Assessments, both the influencing direct and indirect energy as sources of greenhouse gas emissions are required. Life Cycle inventories (LCI) were aggregated for a number of optimised machinery systems and tillage scenarios integrating a four crop rotation consisting of spring barley, winter barley, winter wheat and winter rape seed. By applying Life Cycle Assessments to a number of tillage scenarios and whole field operations sequences, the energy efficiency and environmental impact in terms of greenhouse gas emissions (GHG) were evaluated. Results showed that the total energy input was reduced by 26% for the reduced tillage system and by 41% for the no-tillage system. Energy used for traction and machine construction contributed between 6 and 8% of the total GHG emission per kg product. The total emission of GHG was 915 g CO2 equivalents per kg product by using the conventional tillage system, 817 g CO2 equivalents for the reduced tillage system and 855 g CO2 equivalents for the no tillage system. The no tillage system was expected to yield 10% less. The mineralisation in the soil contributed the most (50–60%) to this emission, while the fertiliser production contributed with 28–33%. The results stress the importance of applying a systems approach to capture the implications of, for example, sustained yields as otherwise the environmental benefits can be compromised.
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Climate sets the limits to plant growth but does climate determine the global distribution of major biomes? I suggest methods for evaluating whether vegetation is largely climate or consumer-controlled, focusing on large mammal herbivores and fire as influential consumers. Large parts of the world appear not to be at equilibrium with climate. Consumer-controlled ecosystems are ancient and diverse. Their distinctive ecology warrants special attention. Abbreviations: DGVM = Dynamic Global Vegetation Model; HSS = Hanston et al. (1960).
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The objectives of this analysis were to estimate historic (pre-European settlement) enteric CH(4) emissions from wild ruminants in the contiguous United States and compare these with present-day CH(4) emissions from farmed ruminants. The analysis included bison, elk (wapiti), and deer (white-tailed and mule). Wild ruminants such as moose, antelope (pronghorn), caribou, and mountain sheep and goat were not included in the analysis because their natural range is mostly outside the contiguous United States or because they have relatively small population sizes. Data for presettlement and present-day population sizes, animal BW, feed intake, and CH(4) emission factors were adopted from various sources. Present-day CH(4) emissions from livestock were from recent United States Environmental Protection Agency estimates. The most important factor determining CH(4) emissions from wild ruminants in the presettlement period was the size of the bison population. Overall, enteric CH(4) emissions from bison, elk, and deer in the presettlement period were about 86% (assuming bison population size of 50 million) of the current CH(4) emissions from farmed ruminants in the United States. Present-day CH(4) emissions from wild ruminants (bison, elk, and deer) were estimated at 0.28 Tg/yr, or 4.3% of the emissions from domestic ruminants. Due to its population size (estimated at 25 million), the white-tailed deer is the most significant present-day wild ruminant contributor to enteric CH(4) emissions in the contiguous United States.
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1. A traditional approach to the nutritional ecology of herbivores is that larger animals can tolerate a diet of lesser quality due to a higher digestive efficiency bestowed on them by comparatively long ingesta retention times and lower relative energy requirements. 2. There are important physiological disadvantages that larger animals must compensate for, namely a lower gut surface : gut volume ratio, larger ingesta particle size and greater losses of faecal bacterial material due to more fermentation. Compensating adaptations could include an increased surface enlargement in larger animals, increased absorption rates per unit of gut surface, and increased gut motility to enhance mixing of ingesta. 3. A lower surface : volume ratio, particularly in sacciform forestomach structures, could be a reason for the fact that methane production is of significant scope mainly in large herbivores and not in small herbivores with comparably long retention times; in the latter, the substrate for methanogenesis – the volatile fatty acids – could be absorbed faster due to a more favourable gut surface : volume ratio. 4. Existing data suggest that in herbivores, an increase in fibre digestibility is not necessarily accompanied by an increase in overall apparent dry matter digestibility. This indicates a comparative decrease of the apparent digestibility of non-fibre material, either due to a lesser utilization of non-fibre substrate or an increased loss of endogenous/bacterial substance. Quantitative research on these mechanisms is warranted in order to evaluate whether an increase in body size represents a net increase of digestive efficiency or just a shift of digestive focus.
The meat crisis: developing more sustainable and ethical production and consumption, 2 nd edn
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