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Abstract

Livestock contribute to food security by supplying essential macro- and micro-nutrients, providing manure and draught power, and generating income. But they also consume food edible by humans and graze on pastures that could be used for crop production. Livestock, especially ruminants, are often seen as poor converters of feed into food products. This paper analyses global livestock feed rations and feed conversion ratios, with specific insight on the diversity in production systems and feed materials. Results estimate that livestock consume 6 billion tonnes of feed (dry matter) annually – including one third of global cereal production – of which 86% is made of materials that are currently not eaten by humans. In addition, soybean cakes, which production can be considered as main driver or land-use, represent 4% of the global livestock feed intake. Producing 1 kg of boneless meat requires an average of 2.8 kg human-edible feed in ruminant systems and 3.2 kg in monogastric systems. While livestock is estimated to use 2.5 billion ha of land, modest improvements in feed use efficiency can reduce further expansion.
... This is proved by cereal grains which, due to low amounts ingested by ruminants, cover only 13% of the world's feed demand in 2010 while they make up 60%-70% of the pig feed demand. Although 2% of livestock was made up of pigs in 2010, cereals used for pig feed accounted for around one-quarter of the entire cereal feed production and, consequently, one-fifth of the agricultural land used for cereals feed crops (Steinfeld 2006, FAO 2011, Mottet et al 2017. In addition, to complement the diet with proteins, in 2010, pigs required more than one-third of oilseed demand in the livestock sector and 40% of that of soybeans (Mottet et al 2017, FAOSTAT 2018. ...
... Although 2% of livestock was made up of pigs in 2010, cereals used for pig feed accounted for around one-quarter of the entire cereal feed production and, consequently, one-fifth of the agricultural land used for cereals feed crops (Steinfeld 2006, FAO 2011, Mottet et al 2017. In addition, to complement the diet with proteins, in 2010, pigs required more than one-third of oilseed demand in the livestock sector and 40% of that of soybeans (Mottet et al 2017, FAOSTAT 2018. Added to this, one-third of the global agricultural water demand is devoted to the livestock sector (Mekonnen and Hoekstra 2012, Ran et al 2016). ...
... Several authors have, therefore, studied the link between resource use and livestock production (Hoekstra 2012, Gerbens-Leenes et al 2013, Bajželj et al 2014, Ran et al 2016, van Zanten et al 2016, Röös et al 2017, Conijn et al 2018, Heinke et al 2020, with global estimates of food-feed competition (Mottet et al 2017). Some other authors have estimated water and/or land resources associated with pig production in specific regions or countries (Thoma et al 2015, Sporchia et al 2021, but often failing to assess the diversity of animal diets between countries and production systems. ...
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Growing population and rising incomes are leading to an ever-increasing demand for animal-based foods. Pigmeat is currently the most consumed meat globally, even exceeding the consumption of poultry meat. Despite the disproportionate environmental burden of animal production – mostly attributable to associated feed demand, up-to-date country-scale quantifications of the land and water impacts of the concentrate feed (mainly cereals and soybean) and co-products required to support pig production are still missing. In addition, the specific role that international feed trade plays in separating resource use from consumption and in altering resource use efficiencies remains unclear. This paper analyses at a country-scale the internal and external consumption of natural resources (i.e., land and water) to support pig feed production in 2018. Combining data on the country- and production system-specific diets and crop-specific yields with an agro-hydrological model, we find that 64.1 Mha of agricultural land (5% of all croplands) and 332.6 km3 of water (both green and blue) (6% of all agricultural water use) were utilized by China, EU-27 and the United States (accounting for 70% of pigmeat production) to produce pig feed alone. Comparing domestic feed production scenarios with those that also consider the feed trade, we show that global resource consumption tends to be more efficient when considering international feed trade, especially in China and EU-27, while sometimes causing significant environmental impacts. This demonstrates the need to investigate the environmental effects of pig feed associated both with the domestic use of natural resources, but also to the ones displaced by international trade.
... A rapid global growth of population and rising incomes have led to an increasing demand for food, meat, and milk, which are projected to increase by 60, 57, and 48%, respectively between 2005 and 2050 [1]. As animal source food contributed 18% of word's calorie and 25% of protein intake [2], livestock production has been estimated to expand by 21% between 2010 and 2025 [3]. This expected expansion will require an increase in world feed supply from 6.0 to 7.3 billion tons of dry matters [4]. ...
... Various feed grains such as corn, wheat and barley are currently the main ingredients used in animal feeds. However, feeding animals with proteins from human-edible crops may be regarded as a direct competition against human food and may not be sustainable [3]. Thus, it is critical to find new feed resources other than food crops such as soybeans and corn, as well as innovation of feed processing technologies [5]. ...
... In terms of China, the United States, Canada, Spain, Germany etc., over 12 million swine were produced each year which has become the support of the national economy and the main food source of the residents. Therefore, the demand for swine feed is huge, accounting for more than 20% of all animal feed [3]. The development of nutritious and efficient swine feeds to increase swine growth and production is of strategic importance in addressing global food shortages. ...
Article
To meet the sustainable development of the swine feed industry, it is essential to find alternative feed resources and develop new feed processing technologies. Distillers dried grains with solubles (DDGS) is a by-product from the ethanol industry consisting of adequate nutrients for swine and is an excellent choice for the swine farming industry. Here, a strategy of co-fermentation of DDGS and lignocellulosic feedstocks for production of swine feed was discussed. The potential of the DDGS and lignocellulosic feedstocks as feedstock for fermented pig feed and the complementary relationship between them were described. In order to facilitate the swine feed research in co-fermentation of DDGS and lignocellulosic feedstocks, the relevant studies on strain selection, fermentation conditions, targeted metabolism, product nutrition, as well as the growth and health of swine were collected and critically reviewed. This review proposed an approach for the production of easily digestible and highly nutritious swine feed via co-fermentation of DDGS and lignocellulosic feedstocks, which could provide a guide for cleaner swine farming, relieve stress on the increasing demand of high-value swine feed, and finally support the ever-increasing demand of the pork market.
... Similarly, the feedlot sector has been reported to produce less heP than that consumed in North American production systems (hePCE of 0.23, on average; Baber et al., 2018) and Austrian (hePCE of 0.45, for growingfattening bulls' systems; Ertl et al., 2016b). Moreover, a previous study estimated an hePCE of 0.24 and 0.28 in feedlots from Organisation for Economic Co-operation and Development countries and non-Organisation for Economic Co-operation and Development countries, respectively (Mottet et al., 2017). ...
... Nonetheless, the replacement of corn with by-products from the food industry, such as dried distillers' grains, has been demonstrated to increase the NPC in intensive beef systems (Baber et al., 2018). Indeed, irrespective of animal species or production system, decreasing the amount of potentially human-edible feeds in livestock diets is imperative for improving the net contribution of livestock to the human food supply (Ertl et al., 2015;Mottet et al., 2017;. Otherwise, Ertl et al. (2016a) stated that the inclusion of potentially human-edible feed in ruminant rations depends strongly on regional preconditions and the availability and price of concentrate (grains) versus quality, availability, and price of forage feedstuffs. ...
Article
Sustainable intensification of tropical grasslands has been identified by researchers and stakeholders as a solution to decrease greenhouse gas emissions and deforestation. However, there are concerns about food security and the role of livestock in feed-food competition between animals and humans involving land and other resources. We aimed to determine the net protein contribution (NPC), a feed-food competitiveness index, of tropical beef cattle raised on extensive systems or finished in pastures or conventional feedlots, under different levels of intensification. We modelled five scenarios, from cow-calf to slaughter, based on common beef cattle practices in Brazil, whose main production system is grazing. Scenario 1 represented the lowest level of intensification and the most extensive system. Scenario 2 represented a moderately extensive system. Scenarios 3, 4, and 5 represented different degrees and practices of intensification, with animals in cow-calf and stocker phases raised solely on well-managed permanent pastures. In Scenario 3, the animals were finished in a feedlot. In Scenarios 4 and 5, all animals in the stocker phase received a protein-energy supplement, but in Scenario 4, animals were finished in a permanent pasture with high-concentrate intake. In Scenario 5, animals were finished in a feedlot. The human-edible protein (heP) conversion efficiency (hePCE) was calculated as the ratio of heP produced (meat) to heP consumed as feed, and the NPC was the product of hePCE using the protein quality ratio, accounting for the digestible indispensable amino acid score content. An hePCE > 1 indicated that meat production did not compete with humans for food, and an NPC > 1 indicated that it contributed positively to meet human requirements. Meat production and heP intake consistently increased with intensification. The greatest hePCE values were from Scenarios 1 (9.2), 2 (2.2), and 3 (1.2), which were essentially pasture-fed systems, compared to Scenarios 4 and 5 (average of 1.0). The NPC varied from 24.1 (Scenario 1) to 2.6 (Scenario 5). The area required to produce 1 kg of carcass decreased from 147 to 45 m², and the slaughter age decreased from 36 to 21 months from the most extensive to intensive systems. Brazilian beef cattle production contributes positively to the protein requirements of humans without limiting human food supplies. The intensification of tropical grazing beef systems is a key strategy to save land and produce more meat without limiting food for humans, playing an important role in the food security agenda.
... Agriculture currently occupies 38 percent of the world's terrestrial land surface, with about 12 percent devoted to crops and about 25 percent to livestock rearing and grazing (Foley et al., 2011). Of the area used for cereal production, 31 percent is devoted to animal feed (Mottet et al., 2017). Although land clearing has slowed since the 1950s relative to the previous century in temperate latitudes, it has shifted to tropical highly biodiverse forests in Latin America, Southeast Asia and Africa (IPBES, Ramankutty et al., 2018). ...
Chapter
Over fifty years of global conservation has failed to bend the curve of biodiversity loss, so we need to transform the ways we govern biodiversity. The UN Convention on Biological Diversity aims to develop and implement a transformative framework for the coming decades. However, the question of what transformative biodiversity governance entails and how it can be implemented is complex. This book argues that transformative biodiversity governance means prioritizing ecocentric, compassionate and just sustainable development. This involves implementing five governance approaches - integrative, inclusive, adaptive, transdisciplinary and anticipatory governance - in conjunction and focused on the underlying causes of biodiversity loss and unsustainability. Transforming Biodiversity Governance is an invaluable source for academics, policy makers and practitioners working in biodiversity and sustainability governance. This is one of a series of publications associated with the Earth System Governance Project. For more publications, see www.cambridge.org/earth-system-governance. This title is also available as Open Access on Cambridge Core.
... Because of the increasing world demand for meat products, and the current economic and environmental context, there is a need to improve feed efficiency in livestock farming systems (MacLeod et al., 2018). This is particularly true for beef cattle which have a conversion rate of feeds into animal products that is considerably lower than that of other species (Mottet et al., 2017). Residual feed intake (RFI) is one of the preferred feed efficiency criteria for genetic selection because of its moderate heritability and uncorrelated response with animal BW and gain (Cantalapiedra-Hijar et al., 2018). ...
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Protein metabolism and body composition have been identified as major determinants of residual feed intake (RFI) in beef cattle fed high-starch fattening diets. This study aimed to evaluate if these two identified RFI determinants in beef cattle are the same across two contrasting silage-based diets. During two consecutive years, an 84-day feed efficiency test (Test A) immediately followed by a second 112-day feed efficiency test (Test B) was carried out using a total of 100 animals offered either one of two diets (either corn silage- or grass silage-based) over 196 days. At the end of Test A, the 32 animals most divergent for RFI (16 extreme RFI animals per diet, eight low RFI and eight high RFI) were identified and evaluated during Test B for their i) N use efficiency (NUE; N retention/N intake) calculated either from a 10-d nitrogen balance trial or from estimations based on body composition changes occurring during the whole experiment (Test A and Test B; 196 days), ii) carcass and whole-body protein turnover rates analysed through the 3-methyl-histidine urinary excretion and the N isotopic turnover rates of urine, respectively, and iii) body composition measured at the slaughterhouse at the end of Test B. Oxygen consumption was measured during Test B for the 100 animals by two GreenFeed systems. Irrespective of the diet, efficient RFI animals tended (P = 0.08) to improve their NUE when N retention was estimated for 196 days or when considering their lower urinary urea-N to total N ratio (P = 0.03). In contrast, NUE calculated during the 10-d N balance showed no differences (P = 0.65) across RFI groups suggesting that this method may not be suitable to capture small NUE differences. Efficient RFI individuals presented higher dressing percentage and muscle deposition in the carcass (P = 0.003) but lighter rumen (P = 0.001), and a trend for lower oxygen consumption (P = 0.08) than inefficient RFI animals irrespective of the diet. Lower protein degradation rates of skeletal muscle and lower protein synthesis rates of plasma proteins were found in efficient RFI cattle but only with the corn silage-based diet (RFI × Diet; P = 0.02). The higher insulinaemia associated with the corn silage-based diet (P = 0.001) seemed to be a key metabolic feature explaining the positive association between protein turnover and RFI only in this diet. Feed N was more efficiently used for growth by efficient RFI animals regardless of the diet but lower protein turnover rates in efficient RFI animals were only observed with corn silage-based diets.
... Bien qu'efficients pour valoriser des ressources non consommables par l'homme, les ruminants laitiers sont en compétition sur l'occupation des surfaces. A l'échelle mondiale, l'élevage consomme 32 % des grains, 40 % des terres arables et 700 millions d'hectares de prairies potentiellement cultivables (Mottet et al., 2017). En France, cela concerne surtout les systèmes bovins laitiers de plaine où des surfaces cultivables sont destinées au maïs ensilage, au méteil ou aux prairies temporaires. ...
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Les systèmes laitiers français (vache, chèvre et brebis) présentent une richesse de par leur diversité, notamment selon leurs systèmes alimentaires. Les aliments consommés peuvent être en concurrence avec l'alimentation humaine (céréales, légumineuses à graines, maïs ensilage) ou non (prairies, parcours). Les efficiences énergétiques et protéiques, en brut et en net ont été évaluées. L'approche nette permet de mieux prendre en compte la compétition « feed-food ». Les systèmes laitiers sont consommateurs nets d'énergie et producteurs nets de protéines pour l'homme, avec de meilleurs résultats en systèmes herbagers. A l'échelle nationale, l'efficience protéique nette est de 1,16 pour les brebis, 1,12 pour les chèvres et 1,88 pour les vaches. Il existe des marges d'amélioration technique dans les trois filières. French dairy systems (cow, goat, ewe) present an important diversity, due to different feeding systems. Feeds consumed by the herds can be human edible (cereals, legumes, maize silage) or not (grasslands, wild grass areas). Energy and protein conversion efficiencies have been evaluated. The net efficiency approach allows to better take into account the "feed-food" competition. Dairy systems are net consumers of energy and net producers of proteins, with better efficiencies for systems based on grass. At national scale, net protein efficiencies are respectively 1.16 for ewes, 1.12 for goats and 1.88 for cows. Technical improvement have been identified for all these dairy sectors.
... 1,12 In both narratives, land suitability and therefore competition between resources for feed and for food production is mostly not addressed. 13,14 Naturally, when resources are suitable to be allocated for feed and for food production, choices need to be made that have consequences for the sustainability of the food system. In circular food systems, resources are prioritised for human food first, and animal feed is allocated as a second priority. ...
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Background National food-based dietary guidelines (FBDGs) are generally designed from a human health perspective and often disregard sustainability aspects. Circular food production systems are a promising solution to achieve sustainable healthy diets. In such systems, closing nutrient cycles where possible and minimising external inputs contribute to reducing environmental impacts. This change could be made by limiting livestock feed to available low-opportunity-cost biomass (LOCB). We examined the compatibility of national dietary guidelines for animal products with livestock production on the basis of the feed supplied by available LOCB. Methods We investigated whether the national dietary recommendations for animal products for Bulgaria, Malta, the Netherlands, Sweden, and Switzerland could be met with domestically available LOCB. We used an optimisation model that allocates feed resources to different species of farm animals. Of the resulting scenarios, we assessed the nutritional feasibility, climate impact, and land use. Findings Our results showed the environmental benefits of reducing the recommended animal products in the FBDGs, and that animal products from LOCB could provide between 22% (Netherlands) and 47% (Switzerland) of total protein contributions of the FBDGs. This range covers a substantial part of the nutritional needs of the studied populations. To fully meet these needs, consumption of plant-based food could be increased. Interpretation Our results contribute to the discussion of what quantities of animal products in dietary guidelines are compatible with circular food systems. Thus, national dietary recommendations for animal products should be revised and recommended quantities lowered. This finding is consistent with recent efforts to include sustainability criteria in dietary guidelines. Funding Swiss National Science Foundation and the Dutch Research Council.
... Climate change is an increasing threat to mountain ecosystems (Schmeller et al. 2018;Vicente-Serrano et al. 2021;Lemus-Canovas and Lopez-Bustins 2021), and hence also a threat to grazing livestock farmers in mountainous regions (Fuhrer et al. 2014). Farmers need to hedge against these impacts, e.g., through insurance (Vroege et al. 2019), adding cropland feed to ruminant livestock diets (Thornton and Herrero 2014;Mottet et al. 2017), or decreasing stocking densities (Stolze et al. 2019). All measures are prone to invoke additional or opportunity costs. ...
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Mountain pastures are embedded in highly sensitive mountain ecosystems and provide forage for livestock during summer. In years when forage in the lowlands becomes scarce due to over-grazing and land degradation, or climate-related extreme events such as droughts, increasing stocking densities or expanding grazed areas in mountain pastures provide an additional and cost-efficient forage source. Their utilization highly depends on the management decisions of farmers and practices on their own agricultural land. To predict future land use and concomitant ecological impacts, it is crucial to understand the complex interplay between the decisions of farmers as well as the socio-economic and climatic environment. To understand these interactions, we use the agent-based part of the SECLAND model to analyze the future systemic feedback between climate change, land owner’s decisions on land use, and land use change on agricultural land and mountain pastures in the department of Ariège, France. We develop three land use scenarios for a sustainability-driven, a business-as-usual, and a scenario driven by fossil-fueled economic growth. In all scenarios, 32–46% of farms cease to exist, while active farms intensify their land use. On mountain pastures, results show increasing stocking densities up to the maximum carrying capacity of 0.3 livestock units per hectare, especially under the scenario with strong climate change effects and increased extreme events. Additionally, these patterns are strongly shaped by farm succession, vegetation regrowth on unused mountain pastures, and the search for cost-efficient forage resources. Such high stocking densities on mountain pastures increase the pressure on the ecosystem through manure droppings and the introduction of alien microbes, calling for considerate management to avoid conflicting situations. Agent-based models such as that used in this study enable researchers to untangle the described complex interactions between grazing livestock, and the utilization of lowland and mountain pastures in European mountain agroecosystems.
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Produced from proliferating cells in bioreactors with a controlled culture medium, “cultured meat” has been presented by its supporters, who are mainly private actors (start-ups), as a sustainable solution to meet the growing demand for animal proteins without weaknesses of animal husbandry in terms of environmental impact, animal welfare or even health. The aim of this chapter is to take stock of current knowledge on the potential benefits and pitfalls of this novel product. Since robust scientific arguments are lacking on these aspects, there is no consensus on the health and nutritional qualities of “cultured meat” for human consumption and on its potential low environmental impact. In addition, many issues related to the market, legislation, ethics and consumer perception remain to be addressed. The way in which this new product is regarded appears to be influenced by many factors related mainly to its price, as well as to the perception of safety, sensory traits but also environmental and nutritional issues. Therefore, research by universities and public research institutes indicates that “cultured meat” production does not present any major advantages in economic, nutritional, sensory, environmental, ethical or social terms compared to conventional meat. Thus, a more balanced diet by diversifying our sources of plant and animal proteins, consuming other meat substitutes, and reducing food losses and waste appear to be more effective short-term solutions to the urgent need of producing enough food for the growing human population (while reducing environmental degradation and animal suffering).
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This chapter introduces topics, concepts, relationships, and tools that are essential to understanding the effects of agriculture on water quality, the significance of these effects, and economic and technological drivers of water pollution from agriculture. The chapter also introduces a systematic watershed-based paradigm for understanding and addressing agriculture and tools used for watershed planning. The chapter begins with a description of the types of water quality problems that result from agricultural production and their economic and ecological significance. The evolution of agriculture as a significant source of water quality problems is connected to economic and technological developments in agricultural production. The chapter turns from causes and consequences to introducing physical processes and relationships at multiple spatial scales, from field to watershed, that must be understood to design effective and efficient solutions. The chapter concludes with the introduction to the watershed-based management and various types of modeling tools used in planning and policy design.
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In 2000, the Food and Agricultural Organisation (FAO) projected that global demand for animal source food (ASF) would double by 2050 (Alexandratos and Bruinsma, 2012). Although these projections were revised slightly during recent years, they form the basis of many scientific and policy documents related to livestock production. Those projections, however, are based on global trends for a growing population and increasing incomes and urbanization, but not based on ensuring global nutrition security in a sustainable way. Currently, the world’s livestock sector adds to the total anthropogenic emissions of greenhouse gases and competes for scarce resources, such as land, water, and fossil-energy. Without changes to reduce the environmental impact, concerns about the environment will only increase further. We asked ourselves, how and why livestock production is essential and what would be the proportion of ASF in human diets to ensure nutrition security in a sustainable way? As land is a strict limitation of nutrition security, we took a land-use perspective, irrespective of socio- economic or technical constraints.
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Livestock contributes directly to the livelihoods and food security of almost a billion people and affects the diet and health of many more. With estimated standing populations of 1.43 billion cattle, 1.87 billion sheep and goats, 0.98 billion pigs, and 19.60 billion chickens, reliable and accessible information on the distribution and abundance of livestock is needed for a many reasons. These include analyses of the social and economic aspects of the livestock sector; the environmental impacts of livestock such as the production and management of waste, greenhouse gas emissions and livestock-related land-use change; and large-scale public health and epidemiological investigations. The Gridded Livestock of the World (GLW) database, produced in 2007, provided modelled livestock densities of the world, adjusted to match official (FAOSTAT) national estimates for the reference year 2005, at a spatial resolution of 3 minutes of arc (about 5×5 km at the equator). Recent methodological improvements have significantly enhanced these distributions: more up-to date and detailed sub-national livestock statistics have been collected; a new, higher resolution set of predictor variables is used; and the analytical procedure has been revised and extended to include a more systematic assessment of model accuracy and the representation of uncertainties associated with the predictions. This paper describes the current approach in detail and presents new global distribution maps at 1 km resolution for cattle, pigs and chickens, and a partial distribution map for ducks. These digital layers are made publically available via the Livestock Geo-Wiki (http://www.livestock.geo-wiki.org), as will be the maps of other livestock types as they are produced.
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We present a unique, biologically consistent, spatially disaggregated global livestock dataset containing information on biomass use, production, feed efficiency, excretion, and greenhouse gas emissions for 28 regions, 8 livestock production systems, 4 animal species (cattle, small ruminants, pigs, and poultry), and 3 livestock products (milk, meat, and eggs). The dataset contains over 50 new global maps containing high-resolution information for understanding the multiple roles (biophysical, economic, social) that livestock can play in different parts of the world. The dataset highlights: (i) feed efficiency as a key driver of productivity, resource use, and greenhouse gas emission intensities, with vast differences between production systems and animal products; (ii) the importance of grasslands as a global resource, supplying almost 50% of biomass for animals while continuing to be at the epicentre of land conversion processes; and (iii) the importance of mixed crop-livestock systems, producing the greater part of animal production (over 60%) in both the developed and the developing world. These data provide critical information for developing targeted, sustainable solutions for the livestock sector and its widely ranging contribution to the global food system.
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Eating meat has been an important component of human evolution and rising meat consumption has made a major contribution to improved nutrition. Expanding the current practices of meat production would worsen its already considerable environmental consequences but more environmentally sensitive ways of meat production are possible. Although they could not match the current levels of meat supply, they could provide nutritionally adequate levels worldwide. This would mean a break with historical trends but such a shift is already underway in many affluent countries and demographic and economic factors are likely to strengthen it in decades ahead.
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Growing global population figures and per-capita incomes imply an increase in food demand and pressure to expand agricultural land. Agricultural expansion into natural ecosystems affects biodiversity and leads to substantial carbon dioxide emissions. Considerable attention has been paid to prospects for increasing food availability, and limiting agricultural expansion, through higher yields on cropland. In contrast, prospects for efficiency improvements in the entire food-chain and dietary changes toward less land-demanding food have not been explored as extensively. In this study, we present model-based scenarios of global agricultural land use in 2030, as a basis for investigating the potential for land-minimized growth of world food supply through: (i) faster growth in feed-to-food efficiency in animal food production; (ii) decreased food wastage; and (iii) dietary changes in favor of vegetable food and less land-demanding meat. The scenarios are based in part on projections of global food agriculture for 2030 by the Food and Agriculture Organization of the United Nations, FAO. The scenario calculations were carried out by means of a physical model of the global food and agriculture system that calculates the land area and crops/pasture production necessary to provide for a given level of food consumption. In the reference scenario - developed to represent the FAO projections - global agricultural area expands from the current 5.1 billion ha to 5.4 billion ha in 2030. In the faster-yet-feasible livestock productivity growth scenario, global agricultural land use decreases to 4.8 billion ha. In a third scenario, combining the higher productivity growth with a substitution of pork and/or poultry for 20% of ruminant meat, land use drops further, to 4.4 billion ha. In a fourth scenario, applied mainly to high-income regions, that assumes a minor transition towards vegetarian food (25% decrease in meat consumption) and a somewhat lower food wastage rate, land use in these regions decreases further, by about 15%.