There has been rapid global expansion of production and consumption of animal products which is expected to continue to grow. The emerging large-scale operations increasingly cater for the rapidly growing markets for meat, milk and eggs. Nonetheless, smallholder production remains predominant in global agriculture and livestock production. Domesticated mammals and birds contribute directly to the livelihoods of hundreds of millions of people, including an estimated 70% of the world’s rural poor. They provide a wide range of products and services including food, transport, fiber, fuel and fertilizer.
The increasing production and consumption of animal products has made the livestock production the largest user of agricultural land, leaving a significant imprint on the environment and natural resources. Additionally, the production of meat and dairy products is a major driver of climate change (CC) with high greenhouse gas (GHG) emissions, but it can also significantly contribute to the necessary mitigation effort. (FAO, 2015)
The livestock sector is heterogeneous in nature, with practices and approaches influenced by contextual factors like climatic and biophysical conditions as well as levels of economic and infrastructural development, and institutional factors. This makes identifying appropriate, context-specific strategies complicated, particularly where there may be distinct or competing objectives like economic development, biodiversity, food security and water management alongside emissions reductions. (Bailey et al., 2014)
According to actual findings, livestock increasingly plays an ambiguous role in climate change and food security (FAO, 2016c):
- Global demand for livestock products will increase by 70% by 2050
- An estimated 1 billion poor depend on livestock for food and income
- The livestock sector contributes to human-induced GHG emissions for 14.5% and is a large user of natural resources
- CC has its impact on animal genetic resources and the multitude of livestock production systems (FAO, 2015)
- Increased complexity by increased interdependency of the factors above
Livestock and livelihoods
The agricultural sector plays a highly important role in many countries’ economies. In Chad and Somalia for example, it still accounts for 52.4% and 68.3% of the GDP, respectively, while in Germany this number is only 0.6%. (World Bank, 2015) The livestock sector, supporting about 1.3 billion producers and retailers, contributes 40–50% of agricultural GDP. (Herrero et al., 2016) These numbers demonstrate the great economic importance in developing countries as well as for smallholder farmers with low financial resources. Most poor livestock keepers live in South Asia and sub-Saharan Africa and their absolute numbers are increasing. (Robinson et al., 2011)
About 50-75% of the world’s extreme poor depend on agriculture as part of their livelihood. Livestock provides them with a wide range of products and services including food, transportation, fiber, fuel and fertilizer. A variety of characteristics makes livestock a crucial contributor to sustainable rural development. Livestock products provide an example of high-value marketable agricultural produce that can be produced at small-scale and are therefore important for poverty reduction. The products’ relatively high income elasticity makes livestock particularly attractive as a means for rural households to participate in urban-based economic growth. Livestock is also a productive asset and it directly contributes to farm output through animal traction as well as indirectly as a store of wealth for future investment. Furthermore, they contribute to soil fertility and recycling of agricultural waste. (FAO, 2016b)
Many livestock keepers directly benefit from the increasing demand for livestock products which lies at 6-8% annually. Also increasing labor demand, linkages with the feed and processing industry as well as food security through stronger supply consequent lower prices for animal products can benefit smallholder farmers. The potential contribution of the livestock sector development to the livelihood of the poor is thus very significant. (FAO, 2016b) Finally, many grazing systems make use of land that is unsuitable for crop production and therefore provide animal products without competing with the production of crops for direct human consumption. (FAO, 2015)
Risk and vulnerability are major challenges for smallholders. Livestock can contribute to risk and vulnerability management in many ways. It complements for labor and capital, and can offset variations in labor/capital availability. Selling livestock can be a more flexible income generation than other agricultural products and livestock is generally more adaptable to environmental shocks than crops. Their mobility and relative omnivorousness increases survivability; adapted animal varieties are able to cope with harsh local environments and environmental risks, finally, also provides food, like milk and eggsand increases food and nutrition security for households. (FAO, 2016a)
Increasing productivity, especially in the small- to medium-scale production systems, is currently constrained by lack of skills, knowledge and appropriate technologies compounded by insufficient access to markets, goods and services, and weak institutions. The result is that both production and productivity remain below potential, and losses and wastage can be high. However, adapted breeds, local feed resources and animal health interventions are available, along with improved and adapted technologies that include sound animal husbandry, on- and off-farm product preservation and value-adding product processing. Together with supportive policies and institutions, they have the potential to substantially improve productivity, income generation and to make a major contribution to poverty reduction in addition to reducing the environmental impact of livestock keeping. (FAO, 2014a)
Livestock’s impact on the global climate
In recent decades, livestock production has increased rapidly, particularly in developing countries. This expansion of the livestock sector is exerting mounting pressure on the world’s natural resources. Land-use changes and land degradation as well as deforestation release enormous amounts of GHG into the atmosphere. The entire agricultural sector is responsible for around 5.3 billion tons of GHG emissions and livestock farming accounts for around 14.5% of this number. (FAO, 2015) The strong projected growth of this sector will result in higher emission shares and volumes over time.
Nitrous oxide (N2O), methane (CH4) and carbon dioxide (CO2) are the three main GHG emitted by the livestock sector (Hristov et al., 2013). Methane emissions mostly originate from enteric fermentation of ruminants (cattle, buffalo, sheep, goat and camels); Methane and NO2 emissions from manure management; Carbon Dioxide and NO2 emissions from feed production, processing and transport. Further emissions arise from land-use change like the conversion of forest into agricultural land or pastures. (Gerber et al., 2013)
Beef and cow milk production account for the majority of emissions, respectively contributing 41% (2,495 million t CO2-eq) and 20% (2,128 million t CO2-eq) of livestock emissions. Pig meat as well as poultry meat and eggs contribute 9% (668 million t CO2-eq) and 8% respectively. Beef and milk production have higher emission intensities (emissions per kg/l of product) in extensive production systems due to low feed digestivity, less efficient herd management practices and low reproduction performance. This relationship between emission intensity and productivity is not clearly observed in monogastric species, as highly productive systems rely on high emission intensity feed. (Gerber et al, 2013)
As the livestock sector is so diverse and context specific, GHG emission sources also vary significantly. In Latin America and the Caribbean for example, one third of the emissions are related to pasture extension into forested areas. In pork and poultry supply chains, emissions mainly derive from feed production due to the use of high emission intensity feed. For pork and chicken egg production, manure storage and processing are also an important source for emissions. In pork production, lowest emission intensities are backyard systems, which rely on feed with low emissions, and among industrial systems which are the most efficient at converting feed into animal products. Chicken meat and eggs have low emission intensities compared with other livestock products. (Gerber et al, 2013)
Dividing GHG emissions by activity, feed production and processing as well as enteric fermentation from ruminants are the two main sources of emissions, representing 45% and 39% of sector emissions, respectively. Manure storage and processing accounts for 10%. The remainder is attributable to the processing and transportation of animal products. Included in feed production, the expansion of pasture and feed crops into forests accounts for about 9% of the sector’s emissions. Cutting across categories, the use of fossil fuel along all supply chains accounts for about 20% of emissions. (Gerber et al, 2013)
Climate change impact on the livestock sector
The livestock sector is not only a major contributor to GHG emissions; it also highly suffers from the consequences of CC, which comes as an additional driver of change in a global livestock sector that is already highly dynamic. Changes in climate over the last 30 years have already reduced global agricultural production in the range 1-5 % per decade. (Thornton et al., 2015) The negative impacts of climate variability, changing precipitation patterns and temperatures as well as increasing meteorological extremes on livestock farming are manifold. Each livestock production system however is affected differently by CC. Land-based systems (livestock graze pastures and rangelands or are kept on mixed crop–livestock farms) rely largely on local resources and are relatively exposed to local-scale environmental changes. Large-scale “landless” or “industrial” production systems are more able to isolate animals from changes in the local environment. However, they heavily rely on external inputs, the supply and affordability of which are potentially affected by CC. (FAO, 2015)
Heat stress, for example, reduces animals’ appetites, production and fertility, and increases mortality rates. In general, high-output breeds from temperate regions are not well adapted to high temperatures. If they are introduced into areas with hot climate, particularly if humidity is also high and their diets are based on poor-quality forage, the animals suffer from heat stress and do not produce to their full potential. (FAO, 2015) Projections indicate substantial reductions in forage availability in some regions, and widespread negative impacts on forage quality and thus on livestock productivity. These will have consequent impacts on incomes and food security of the many millions farmers who depend on livestock-based systems. (Thornton et al., 2015) Feed supplies may be affected both locally (e.g. loss of grazing land because of drought) and globally (e.g. rising grain prices). Animals’ water requirements increase with temperatures, but in many areas, CC is likely to decrease water availability and supplies become more unpredictable. Finally, also genetic resources in agriculture are increasingly lost due to CC, which makes a future adaptation to changing environments more difficult, especially for small-scale farmers that depend on local breeds. (FAO, 2015)
How the livestock sector could adapt to a changing climate
The necessity for CC-adaptation in the livestock sector to reduce the vulnerability of people and supporting them in dealing with the impacts is immense. Traditional coping mechanisms might not be enough any longer and expected changes might exceed human and animal capacity to adapt. There is no blueprint solution for adaptation and measures need to be tailored to specific contexts. Many options exist that can help livestock keepers adapt to CC, but there appear to be no options that are widely applicable and do not have constraints to their adoption. (Thornton et al., 2015)
Changes in livestock practices could include the diversification, intensification and/or integration of pasture management, livestock and crop production; altering the timing of operations; conserving nature and ecosystems; modifying stock routings and distances; introducing mixed livestock farming systems, such as stall-fed systems and pasture grazing. But also market-based solutions should be included, like the promotion of interregional trade and credit schemes. Institutional and policy interventions could also assist adaptation, for example by removing or introducing subsidies, insurance systems, income diversification practices, establishing livestock early warning systems and improved soil and water management. Reaching livestock keepers for capacity building regarding adaptation to CC and innovation technologies and practices is crucial to improve fodder supply and consequently nutrition and health of herds. Finally, also affordable changes to livestock management systems need to be developed. These could include the provision of (natural) shade and water to reduce heat stress from increased temperature; the reduction of livestock numbers to increase animal productivity and efficiency or infrastructure to harvest and store rainwater. (IFAD, 2009)
Scientific research and technology development could increase the understanding of the impacts of CC on livestock, improving animal health and developing new breeds and genetic types. (IFAD, 2009)
The role of livestock diversity and genetic resources
Genetic diversity is a vital resource for the livestock sector. Most livestock diversity is maintained in situ by farmers and pastoralists. Many local breeds are already adapted to harsh living conditions. Measures to promote the sustainable use and development of these breeds, and where necessary in situ and ex situ conservation measures to prevent their loss, are urgently needed. However, developing countries are usually characterized by a lack of technology in livestock breeding and agricultural programs that might otherwise help to speed adaptation. Adaptation strategies address not only the tolerance of livestock to heat, but also their ability to survive, grow and reproduce in conditions of poor nutrition, parasites and diseases. Such measures could include the identification and strengthening of local breeds that have adapted to local climatic stress and feed sources and the improvement of local genetics through cross-breeding with (introduced) heat and disease tolerant breeds. If climate change is faster than natural selection, the risk to the survival and adaptation of the new breed is greater. (IFAD, 2009) At present, however, gene flow on a global scale mainly remains focused largely on the movement of high-output breeds that need highly controlled production environments in the global North rather than on the movement of locally adapted breeds into equivalent agro-ecological zones into or within the global South. Within species, certain breeds and lines have been intensively bred for high output and good feed-conversion ratios in high external input production environments. If mitigation policies were to promote the use of a narrow range of species and breeds within a narrow range of production systems, genetic diversity might be put at risk. (FAO, 2015)
Mitigation potential in the livestock sector
The livestock sector should be an integer part of any solution to CC, as its GHG emissions are substantial but have great potential to be reduced by mitigation interventions. As a large user of natural resources and contributor to CC, the livestock sector needs to address its environmental footprint. (Gerber et al., 2013)
Emission intensities (emissions per kg/l of animal product) vary greatly between production systems. The gap between the production units with the lowest emission intensities and those with the highest emission intensities represents the potential for mitigation. Emission reductions of 18 – 30% (or 1.8 to 1.1 Gt CO2 eq) are possible if producers in a given region, production system and climate adopted those practices currently applied by the 10 – 25% of producers with the lowest emission intensity. (Gerber et al, 2013)
The mitigation potential can be achieved within existing systems of all climates, regions and production systems, rather by improving practices than by changing the systems. Possible emission reduction interventions are thus, to a large extent, based on technologies and practices that improve production efficiency at animal and herd levels. Most technologies and practices that mitigate emissions also improve productivity and can therefore contribute to food security and poverty alleviation. (Gerber et al, 2013)
The major mitigation potential lies within low-productive ruminant systems in Latin America and the Caribbean, South Asia and Sub Sahara Africa. Part of the mitigation potential can be achieved through better animal and herd efficiency as well as the use of better quality feed and feed balancing to lower enteric and manure emissions. Manure management practices that ensure the recovery and recycling of nutrients and energy contained in manure and improvements in energy use efficiency along supply chains can further contribute to mitigation. Improved breeding and animal health help to shrink the herd overhead (i.e. unproductive part of the herd) and related emissions. A range of promising technologies like feeding additives, vaccines and genetic selection methods have a strong potential to reduce emissions but require further development and/or longer time frames to be viable mitigation options. Sourcing low emission intensity inputs (feed and energy in particular) is a further option. (Gerber et al, 2013) Better grazing land management holds additional promises for mitigation. Overgrazing increases the loss of soil carbon, but well-managed grazing can increase soil carbon sequestration, and depending on the circumstances even exceed the levels of ungrazed land. (Smith et al., 2008 in FAO, 2015)
New technologies and changes in livestock production practices offer important means to reduce livestock emissions; however are by far not enough. Individual and societal behavior changes are essential to moderate consumption of meat and dairy products. (Bailey et al., 2014) In its latest review of the scientific literature on mitigation in the agriculture sector, the International Panel on Climate Change (IPCC) found that the greatest potential for emissions reduction (up to 8.55 Gt CO2 eq in 2050) exists on the demand side through dietary change and reduction of food waste. This is almost double the maximum emission reduction from supply-side interventions in agriculture as a whole (4.6 Gt CO2 eq). For example, one recent assessment of mitigation opportunities in agriculture estimated that shifting dietary trends to average worldwide per capita meat consumption of 90 g per day, as recommended in Harvard healthy diet, could avoid 2.15 Gt CO2 eq of emissions per year by 2030. (Slingenberg et al., 2014; Bajželj et al., 2014 in Baileys et al., 2014).
Affordable methods for quantifying sequestration, as well as a better understanding of institutional needs and economic viability of this option, are required before implementation at scale. Most mitigations interventions of the livestock sector will result in increased resource use efficiency along the sectors supply chain. Supportive policies, adequate institutional frameworks and more proactive governance are needed to fulfill the sectors mitigation potential and promote its sustainable development. Extension and capacity building can facilitate the knowledge transfer and use of more efficient practices/technologies that are readily available. Financial incentives are important complementary policy tools, particularly for mitigation strategies that increase risks and costs for the farmers. Research and development is vital for increasing the availability and affordability of effective mitigation options. Due to the size and complexity of the livestock sector, concerted and global action by all stakeholder groups is needed to design and implement cost effective and equitable mitigation strategies and policies. (Herrero et al., 2016; Gerber et al., 2013)
International Efforts for Mitigation and Adaptation
The effects of the increased livestock production on environment and climate was already described by FAO in 2006 and later confirmed by different other reports and studies. Negotiations under the United Nations Framework Convention on Climate Change (UNFCCC) have overlooked livestock and mostly focused on forest degradation and deforestation. Of potentially more immediate relevance to livestock, the Global Alliance for Climate-Smart Agriculture (GACSA) – comprising 16 countries and 37 organizations and companies – was launched at the UN Climate Summit in 2014. The objectives include the ‘reduction and/or removal’ of agricultural emissions (UN, 2014 in Bailey et al., 2014). In how far this will address livestock remains to be seen. International finance for agricultural mitigation is also limited. Only few projects under the UN-Clean Development Mechanism (CDM) address agriculture and the sector receives only 4% of the total mitigation finance provided by multilateral development banks. (IPCC, 2014)
The marginalization of livestock within international negotiations is reflected in national emission-reduction targets and plans, where only few targets consider livestock or agriculture. Of the 40 Annex I countries of the UNFCCC (2014), only two have established a quantitative reduction target for livestock-related emissions (FAO, 2014). Internationally binding, non-sector-specific targets under the Kyoto Protocol cover just 1% of global direct emissions from livestock and only two out of 10 countries with the largest livestock populations remain subject to binding emissions reduction commitments. Developing countries’ mitigation plans submitted to the UNFCCC show similar trends. Only eight of the 55 developing countries to submit Nationally Appropriate Mitigation Actions (NAMAs) made mention of the livestock sector and only one country established a quantitative reduction target for livestock emissions. (Bailey et al. 2014) The Intended Nationally Determined Contributions INDCs of 41 African countries specifically mention the livestock sector. While this mostly addresses CC-adaptation, some also include mitigation efforts. It is striking that climate smart agriculture (CSA) – an approach that combines adaptation with mitigation efforts for increased productivity – is named frequently.
Despite the necessity of addressing global meat and dairy consumption to meet climate objectives, no government seems prepared to do so and efforts to moderate meat and dairy consumption are absent from mitigation strategies. The extent of government action is seemingly limited to the inclusion of CC considerations in the dietary recommendations of few countries. Campaigns by major environmental groups to raise awareness of meat and dairy’s climate footprint or encourage dietary change are scarce and have partly been muted. Governments and campaign groups fear that trying to reduce consumer demand for meat and dairy products could lead to possible public intolerance of any attempt to interfere in lifestyle decisions, invites accusations of paternalism and preaching, and risks alienating voters or supporters. These concerns may be greatest in developed, market-based economies where notions of free choice and individual rights predominate. (Laestadius et al. 2014) Many consumers however are not aware of the links between meat and dairy production and consumption and CC, an awareness gap that inhibits a demand-side response. Understanding the livestock sector’s contribution to CC is a precondition for voluntary consumer action to reduce emissions from meat and dairy consumption. But also in other countries, promoting dietary change would necessarily challenge the cultural significance of meat in many societies, and its aspirational status in many developing countries. Finally, attempts to reduce meat and dairy consumption would be likely to mobilize resistance from powerful interest groups of the meat and dairy industry. The continuing trend of increasing global consumption of meat is not compatible with reducing GHG emissions from agriculture. There is a need for research to understand what types of knowledge or interventions could limit the global growth in livestock consumption without threatening the food security or nutritional outcomes of people in developing countries (Herero et al.,2016).
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