It is extremely difficult to separate the different impacts of different models and types of agriculture. Many measures analyze agricultural impact without making a distinction between arable livestock and small industrial farms. However, the following information begins to indicate the scale of the problem.
Eutrophication of a river during the summer in France as a result of nutrient-rich agricultural runoff.
An influential study in 2010 on the water footprints of meat estimated that while vegetables had a footprint of approximately 322 liters per kg and fruits drank up to 962 liters, meat was much thirstier: chicken reached 4,325l / kg, pork at 5,988l / kg, sheep / goat meat at 8,763 l / kg and beef at a stupendous amount of 15,415l / kg. Some non-meat products were also very appetizing: walnuts reached 9,063l / kg.
To put these figures in context: the planet faces increasing water restrictions as our freshwater reservoirs and aquifers dry up. By some estimates, agriculture accounts for about 70% of the water used in the world today, but a 2013 study found that it uses up to 92% of our fresh water, with nearly a third of that related to animal products. .
Farms contribute to water pollution in a number of ways: some of them are more related to agriculture and others to livestock, but it is worth remembering that a third of the world's grain is now fed to animals. FAO believes that the livestock sector, which is growing and intensifying faster than agricultural production, has "serious implications" for water quality.
Types of water pollution include: nutrients (nitrogen and phosphorus from fertilizers and animal excrement); pesticides; sediment; organic matter (substances that require oxygen, such as plant matter and livestock excrement); pathogens (E. coli, etc.); metals (selenium, etc.) and emerging contaminants (drug residues, hormones and feed additives).
The impacts are powerful. Eutrophication is caused by excess nutrients and organic matter (animal feces, food scraps, and crop residues) that cause algae and plants to overgrow and consume all the oxygen in the water body at the expense of other species. A review in 2015 identified 415 coastal bodies that already suffer from these problems. Pesticide contamination can kill weeds and insects outside the agricultural area, with impacts that can be felt throughout the food chain. And although scientists do not yet have complete data on the connection between antibiotic use in animals and increasing levels of antibiotic resistance in the human population, water contamination by antibiotics (which continue to live an active life even after going through the animal and enter the water) is definitely in frame.
Land use and deforestation
Livestock is the world's largest user of land resources, FAO says, “with grazing land and cropland dedicated to food production accounting for nearly 80% of all agricultural land. Food crops are grown on a third of the total farmland, while the total area of land occupied by grass is equivalent to 26% of the ice-free land area.
It is difficult to calculate exactly how much greenhouse gases (GHG) is emitted by the meat industry from farm to fork; Carbon emissions are not officially counted across entire chains in that way, so a series of complicated studies and calculations have attempted to fill the gap.
According to the United Nations Intergovernmental Panel on Climate Change, agriculture, forestry and other land uses account for 24% of greenhouse gases. Attempts to choose the role of animal husbandry have resulted in a large number of numbers, from 6 to 32%: the difference, according to the Meat Atlas, "depends on the basis of the measurement." Should it just be earned, or should it include many other factors? Different models of agriculture have different levels of emissions: this has generated a spirited discussion about extensive versus intensive agriculture and regenerative agriculture, a model that seeks to combine technologies and techniques to regenerate soils and levels of biodiversity while also capturing the carbon.
And the giant companies that dominate the sector? A flagship study from 2017 found that the top three meat companies (JBS, Cargill and Tyson) emitted more greenhouse gases in 2016 than all of France.
Some argue that veganism is the only healthy way forward. A study last year showed, for example, that if all Americans substituted beans for beef, the country would be close to meeting the greenhouse gas targets agreed upon by Barack Obama.
But there are some alternatives. Many environmental groups advocate reducing the amount of meat you eat while improving its quality. But where do you find this meat? The organic movement was founded on the pioneering work of Sir Alfred Howard. It is still relatively small: in Europe, 5.7% of agricultural land is managed organically, but it is influential. There are other agricultural models, such as biodynamic agriculture and permaculture. More recently, some innovators have been fusing technology with environmental principles in the form of agroforestry, silvopastoralism, conservation agriculture, or regenerative agriculture to create farming methods that encompass carbon sequestration, high biodiversity, and good animal welfare. A recent study showed that controlled grazing (a technique that involves moving cows to graze) is an effective way to sequester carbon. However, although organic and biodynamic meats are labeled, regenerative agriculture, at the moment, does not, so you should do your own research from your farmer.
Full original article (in English)
The Food and Agriculture Organization of the United Nations has a huge collection of data and has also published some crucial reports on this topic, including the long shadow of Livestock.
The Atlas of Meat.
Some institutions that do interesting research include Sustain; The Institute for Agriculture and Trade Policy; Brighter Green; Sustainable Food Trust; IPES-food.