Resource Consumption of Current Global Livestock ProductionProduction

3.2.1 Terrestrial Livestock Production

About 45 % of the protein feed share in the global livestock sector comes from grass and leaves, mainly fed to ruminants and 14 % comes from oilcrops (rapeseed, sunflower, cotton etc.), 10 % from soy, 10 % from cereals, 10 % from crop residues and 9 % from by-products and other sources. The proportion of feed production area of cropland has increased from 1970 to 1983 peaking at 46 % and 51 % respectively. Due to substantial yield increases by a factor of 2.7 for global cropland, this proportion decreased to about 37 % nowadays, even though feed production quantity increased tremendously.

Berners-Lee et al. (2018) estimated that 34 % human-edible crop calories are being fed to livestock.

In the last decades, livestock production has undergone dramatic changes, as illustrated in figure 3.8. Between 1961 and 2013, the pasture land area increased by only 5 %, while the crop area increased by 13 %. All livestock production quantities increased tremendously due to population increase and increased demand for animal products.

However, there has been a substantial change in the ratio of herbivore to omnivore derived products. The increase in omnivore products from monogastric animals including pigs, poultry and fish was much higher than the increase in herbivore animal products from polygastrics or ruminants including cattle, mutton (sheep) and goats. The latter are primarily adapted to rely on grass, herbs and leaves, while monogastrics require more energy dense feed and naturally feed on animal protein as well.

Research on intensive livestock production has doubled the efficiency of pigs and chicken converting grain into meat in the last 30 years. As a consequence, prices for meat have been dropping, while cereals for human consumption have increased in prices [Tester and Langridge, 2010].

3.2.2 Aquaculture

Aquaculture is the fastest growing food production industry since 1980, with produc-tion quantities growing faster than the global populaproduc-tion. In 2014 for the first time ever, more fish for human consumption was produced in aquaculture than was caught in fisheries. For 2030 aquaculture is expected to provide 60 % of all fish for human consumption [FAO, 2018].

Aquaculture relies on fishmeal as part of the diet of fish and crustaceans. Of the global fishmeal production, 2 % were used in aquaculture in 1960, 10 % in 1980 and 73 % in 2010, while pigs received 20 % and chicken 5 % in the same year [Shepherd and Jackson, 2013]. Of the world fishery stocks, 30 % are overfished, 60 % are fully fished and less than 10 % have remaining capacity [Little et al., 2016]. Global average fish consumption per capita grew from 9.0 kg in 1961 to 20.2 kg in 2015 [FAO, 2018].

The percentage of fishmeal in aquaculture feed formulations lies between 0 to 50 %, while the percentage of fish oil is between 0 - 25 %. Species like molluscs or filter feeding carps can be farmed without wild caught fish, while farmed marine finfish, eel, salmon and trout require a high input of wild fish in their feed [Naylor et al., 2000]. In 2016, aquaculture produced 80.0 gt of fish, while 90.9 gt were caught in fisheries, of which 19.7 gt were used as feed ingredient [FAO, 2018]. Most fishmeal in aquaculture is used for crustaceans (29 %), followed by salmonids (24 %) and marine fishes (23 %) [Shepherd and Jackson, 2013].

While aquaculture production is rapidly expanding, global wild catches are stagnating

Figure 3.8: Global change in livestock production and agricultural land use in 1961 vs.

2013, after FAO statistics.

and are also expected to remain near current levels. Forage fish, mainly anchovies, her-ring and sardines are required as a source of micronutrients, especially long-chain ω-3 fatty acids (FAs) EPA (eicosapentaenoic acid) and DHA (docosahexaenoic acid). Con-cerns over sustainability issues involving the use of fishmeal and fish oil in aquaculture are increasing as ecological limits of forage fish production are becoming apparent.

However, only in the 2000s did aquaculture become the main consumer of forage fish.

Before that they were mainly used for pig and poultry production. Through the rapid growth of aquaculture, the use of fishmeal for pigs and poultry has declined, while de-mand for fishmeal and fish oil alternatives for aquaculture are rising. Some alternative inputs include algae, insects, yeasts and bacteria [Froehlich et al., 2018]. Over the last decades the percentage of fishmeal and fish oil in aquaculture feed formulations has steadily declined, while it has been replaced with alternative proteins and starch and vegetable oils, mainly from soybeans, other oil crops and grains [Shepherd and Jackson, 2013].

3.2.3 Land Use of Animal Protein Production

While livestock occupies the permanent meadows and pastures that make up about two thirds of the global agricultural area, there is also about 35 - 39 % of the temporary cropping area dedicated to livestock fodder production, according to estimates [Manceron et al., 2014]. Precise data on the total land share for fodder production is not available, as many crops that are used as fodder, are grown for multiple products. For example oil-cakes that are fed to livestock are a by-product of vegetable oil production, for human consumption as well as for biodiesel production. Another example would be bran, which is also used as fodder, a by-product of grain processing [Manceron et al., 2014].

Therefore, the total area percentage of agricultural land used for livestock lies at around 78.8 %, composed of 67.3 % of permanent meadows and pastures and about 37 % of the residual crop land (32.7 %) for feed production. The global area of land dedicated to livestock production is almost the same area as of global forests. However, concerning the global diet, animal products account for 39.6 % of dietary protein and only for 17.8

% of dietary calories (figure 3.5 and 3.4).

The global amount of animal protein produced per year is at around 91 gt (calcu-lation attached in the Appendix A, table A.2), consisting of meat, milk, fish, seafood, eggs, offals, other aquatic products and animal fats. Hence, the global animal protein productivity equals around 23.8 kg/ha/y. This figure also includes fish and seafood from the ocean, lakes and rivers, not included in the agricultural area.

The current protein productivity in kg protein/ha/y for different agricultural products can be seen in two different data sets in figure 3.9 [Clark and Tilman, 2017] and figure 3.10 [Poore and Nemecek, 2018]. In general, plant protein crops are more area-efficient, with legumes at the top, especially soybeans. Herbivore systems generally have the lowest protein production per area [Poore and Nemecek, 2018]. In aquaculture, the

Figure 3.9: Average protein productivity of some livestock and crop production systems, after Clark and Tilman (2017).

farming of most fish and crustaceans requires a certain proportion of fishmeal in the feed formulations, which has no associated land use, as they are produced on land area.

Hence, in these graphics, aquaculture operations look much more efficient than they

Figure 3.10: Average protein productivity of some livestock and crop production systems, after Poore and Nemecek (2018).

truly are, when just land use is considered. The same effect has to be considered for pigs and poultry, as they also receive fishmeal in their diet, but to a lesser extent [Shepherd and Jackson, 2013].

3.3 Food Production in the Context of Sustainable Plane-tary Boundaries

The EAT-Lancet Commission outlined a reference diet in a paper from 2019, which is based on both planetary boundaries and dietary recommendations on a global level.

As planetary boundaries they are taking into account climate change, nitrogen cycling, phosphorus cycling, freshwater use, biodiversity loss and land-system change. Their proposed diet in relation to the current global diet can be seen in figure 3.11. They suggest substantial reductions for red meat and starchy vegetables and increased intake of dairy, fruit, legumes, whole grains and nuts. It is argued that the way the global population has been eating for the past 50 years is the main driver of climate change and biodiversity loss [Willett et al., 2019].

Berners-Lee et al. (2018) argues that current agricultural production is sufficient to feed the world population in 2050, however only if animal product consumption is dras-tically restricted and less human-edible crops are fed to livestock and are directly used for human consumption. Considering a business as usual scenario, crop yields would have to be increased by 119 % until 2050 to feed an expected population of 9.7 billion.

Tilman et al. (2015) states that 60 % of the global grain production is directly con-sumed, while 35 % is used as animal feed and 5 % for biofuels. In wealthy countries, 8,000 kcal of crops are necessary to produce a typical diet containing 3,500 kcal per day, as most calories are needed as animal feed. A population increase of 30 % in 2050 would require a 100 % production increase in agriculture, as demand for animal products is ex-pected to greatly increase, especially in developing countries. Adopting a Mediterranean

Figure 3.11: Diet gap between dietary patterns in 2016 and reference diet intakes of food. The dotted line represents intakes in reference diet, after Willett et al. (2019).

or vegetarian diet is proposed as a means of reducing environmental burden in future agricultural scenarios, due to lower animal product consumption.

Alexandratos et al. (2012) estimate the global production increase for total agricultural production and meat production from 2005/2007 to 2050 at 60 % and 76 %, respectively.

These production increases over this time period are projected to be by 90 % the result of agricultural intensification.

In order to achieve the needed doubling of agricultural production in 2050, 170 % in-creases in nitrogen fertilizer, 140 % increase in phosphate fertilizer, 190 % increase in irrigation and 170 % increase in pesticide usage is expected to be necessary for in-tensification purposes. Only 23 % increase in cropland and 16 % increase in pastures are predicted, as the main driver for production increases is clearly seen in intensifica-tion [Tilman and Clark, 2015].

A review on the sustainability of the omnivorous diet, vegetarian diet and vegan diet was evaluating 16 studies and 18 reviews. The paper used the Life Cycle Impact Assess-ment technique taking into account "environAssess-mental impacts of production, transport, processing, storage, waste disposal and other life stages of food production" in order to analyse the three different diets according to greenhouse gas emissions, land use and water consumption. It was concluded that the vegan diet had the least environmental impact, while the omnivorous diet had the greatest. This is in accordance with a mul-titude of studies showing a clear difference in the respective diets. Animal products are

associated with higher greenhouse gas emissions, land use and water consumption [Chai et al., 2019].

The feeding of human-edible food to livestock results in a loss of available protein of 51 g per capita per day, globally. This is more than the daily requirement for pro-tein [Berners-Lee et al., 2018].