Changing our diet for a wilder world

Status: early draft

This short essay explores how a plant-based or vegan diet could drastically transform our land use to improve and protect biodiversity by allowing the creation of new wilderness areas.

It focuses on Western Europe (Austria, Belgium, France, Germany, Liechtenstein, Luxembourg, Monaco, Netherlands, Switzerland) using data from the Food and Agriculture Organization (FAO) of the United Nations, but it could be transposed to other industrialized regions with the same conclusions. All tables were generated by a script published on GitHub.

Population

Western Europe Human density in Western Europe (GPW v4.10)

Western Europe was home to 191 million humans in 2013 and the population should stabilize around 200 million by the year 2040. At the same time 573 million chickens, 65 million pigs, and 42 million cattle, among other animals, were raised in farms to feed the human population.

Item Population
Humans 190.51
Livestock 765.51
.. Pigs 64.54
.. Cattle 41.85
.. Sheep 11.07
.. Goats 2.04
.. Chickens 572.72
.. Turkeys 35.14
.. Ducks 30.08
.. Other 8.08

Over the past half a century the total number of poultry has been increasing steadily whereas the number of cattle and sheep peaked 30 years ago.

During the same period the human population of Western Europe has become more and more urban, with 78% of the people living in cities in 2013 compared to 69% in 1963. In other words the rural population decreased by 9 million while the urban population increased by 42 million.

Paris Paris, France (Google Maps)

Land Use

Western Europe Human footprint on Western Europe (LWP v3)

Western Europe has a land area of 109 million hectares. Most of it was covered by deciduous trees before human settlement and the beginning of agriculture, but nowadays the forests are reduced to 34 million hectares while crops and pastures use 28 and 25 million hectares respectively.

Item Area
Land 108.52
.. Crops 28.48
..... Permanent crops 1.35
..... Temporary crops 26.40
..... Fallow land 0.74
.. Pastures 24.55
..... Permanent meadows and pastures 17.83
..... Temporary meadows and pastures 6.72
.. Forests 34.44
..... Primary forests 0.16
..... Planted forests 9.97
..... Naturally regenerated forests 24.31
.. Other 21.05

The pastures are grazed by cattle, sheep, and goats, while most chickens and pigs are kept indoors. Crops produce food for both humans and their livestock.

A closer look at the current forests shows that there is virtually no wilderness left in Western Europe, it is one of the most endangered ecosystem in the world. The vast majority of the remaining forests are heavily exploited and about a third of them are reduced to monoculture tree plantations.

Pine Plantations Pine plantations, Landes, France (Google Maps)

Crops

The majority of the area used for crops is dedicated to the cultivation of cereals. In 2013 more than 126 million tonnes of grain were harvested on less than 18 million hectares. With 4 million more hectares dedicated to oils production and less than 3 million for the remaining plants (fruits, roots, vegetables).

Item Prod Area
Crops 269.31 25.38
.. Cereals 125.79 17.56
.. Oils 12.60 4.03
.. Fruits 13.12 1.18
.. Sugars 71.84 0.95
.. Roots 27.65 0.67
.. Vegetables 16.13 0.51
.. Pulses 1.10 0.32
.. Fibres 0.55 0.08
.. Nuts 0.08 0.04
.. Spices 0.03 0.02
.. Drinks 0.41 0.01
.. Other 0.02 0.01

NOTE: The area of crops on this table (25M hectares) differs from the previous table (28M hectares), see: QC Methodology (FAOSTAT)

The next table details the allocation of each type of crops to human food (processed or directly) and to livestock feed. As before, the numbers are expressed in million of tonnes.

Item Prod Supply Proc Food Feed Other
Crops 303.17 315.21 111.00 100.82 65.44 38.23
.. Cereals 125.96 104.03 9.70 22.05 60.52 11.76
.. Sugars 71.82 72.15 66.43 0.00 0.00 5.72
.. Roots 27.61 20.32 0.92 11.99 1.77 5.64
.. Drinks 24.57 24.24 0.85 21.36 0.00 2.04
.. Oils 21.78 40.55 24.87 4.27 1.99 9.58
.. Vegetables 17.02 21.42 0.00 18.72 0.40 2.36
.. Fruits 13.25 29.92 8.24 20.66 0.00 1.05
.. Pulses 1.09 1.21 0.00 0.40 0.76 0.06
.. Nuts 0.07 1.16 0.00 1.15 0.00 0.02
.. Spices 0.00 0.20 0.00 0.22 0.00 0.00

NOTE: Some items on this table differ from the previous table. For example beers and wines are now excluded from cereals and fruits respectively and counted in drinks.

Most of the crops used to feed livestock are cereals. Of the 104 million tonnes available in the domestic supply, about 1/3 goes to human food and 2/3 to livestock feed.

Furthermore, as supply is defined by production and import subtracted by export and changes in stocks, assuming the same balance for the 126 million tonnes of cereals produced, we can estimate that about 11 million hectares of cereal crops out of 18 according to the previous table were used to feed livestock.

Cereal fields Cereal fields, Beauce, France (Google Maps)

Diet

When we look at the food supply (in kcal/capita/day) we see that animal and vegetal products represent respectively 1/3 and 2/3 of the current diet in Western Europe:

Item Calories
Animal Products 1109
.. Meat 514
.. Dairy 492
.. Eggs 49
.. Seafood 54
Vegetal Products 2387
.. Cereals 882
.. Oil 483
.. Sugar 431
.. Drinks 219
.. Fruits 117
.. Roots 114
.. Vegetables 74
.. Nuts 40
.. Pulses 19
.. Other 8

In terms of calories available to humans, converting pastures and crops to animal products is much less efficient than directly consuming those crops in the first place.

It should be noted that some of the land used for pastures is not suitable for growing crops, but with 2/3 of the crops in Western Europe used to feed livestock, and the 1/3 remaining providing 2/3 of the calories consumed by the human population, more than enough crops area is available to replace all animal products with vegetable products.

Plant-based diets have a long history around the world and the modern widespread availability of dietary supplements (vitamins B12 and D most notably) means that a strict vegan diet, properly planned, can be as healthy as any omnivore diets.

Cattle in a pasture Cattle in a pasture, Alps, France (Google Maps)

Conclusion

If all the human population of Western Europe shifted to a plant-based diet, most of the 25 million hectares of pasture and at least a third of the 28 million hectares of crops that are used to feed the livestock could be freed from agriculture while the remaining cropland would be reorganized to prioritize direct human consumption.

The result of this change, after rewilding the land, could double the amount of forests and provide a lot of the space required to protect biodiversity.

A full conversion of the population to a plant-based diet may seems utopian at the moment, but even a moderate shift toward less meat consumption would progressively allow the creation of more natural reserves.

Bavarian Forest Bavarian Forest, Germany (Google Maps)

Annexes

Below are the same tables generated for the whole world (FAOSTAT 2013), mostly equivalent to this great data visualization from Our World In Data.

In less industrialized areas there are more remaining forests, crops take less space than pastures and are less used to feed the livestock, and humans eat less animal products. But the population is still growing and adopting more and more a lifestyle similar to Western Europe.

World populations (in million):

Item Population
Humans 7,213.43
Livestock 28,156.90
.. Cattle 1,434.40
.. Pigs 976.34
.. Sheep 1,132.72
.. Goats 954.72
.. Chickens 20,955.42
.. Ducks 1,111.52
.. Turkeys 450.87
.. Other 1,140.92

World land use (in million hectares):

Item Area
Land 13,021.25
.. Arable land and permanent crops 1,571.97
.. Permanent meadows and pastures 3,309.64
.. Forests 4,005.75
..... Naturally regenerated forests 2,437.26
..... Planted forests 286.93
..... Primary forests 1,281.56
.. Other 4,133.88

World crops areas (in million tonnes and hectares):

Item Prod Area
Crops 8,665.04 1,400.50
.. Cereals 2,768.02 722.32
.. Oils 809.58 261.92
.. Pulses 77.97 80.01
.. Fruits 823.66 63.56
.. Roots 817.52 61.46
.. Vegetables 997.84 54.52
.. Other 97.05 48.77
.. Fibres 78.59 35.32
.. Sugars 2,150.31 31.39
.. Drinks 19.18 24.34
.. Nuts 14.93 11.13
.. Spices 10.37 5.77

World crops balance (in million tonnes):

Item Prod Supply Proc Food Feed Other
Crops 8,436.27 8,289.18 2,191.64 3,532.90 1,196.12 1,376.78
.. Cereals 2,523.35 2,407.01 94.58 1,029.02 873.55 410.48
.. Sugars 2,126.84 2,128.23 1,593.75 32.25 39.74 462.50
.. Vegetables 1,129.61 1,124.93 0.24 982.97 51.71 90.41
.. Roots 811.32 815.70 15.44 443.35 175.29 181.80
.. Oils 753.37 726.49 431.79 131.50 40.20 128.35
.. Fruits 662.13 661.60 53.30 544.88 2.45 62.08
.. Drinks 315.13 312.24 2.53 279.48 0.00 30.49
.. Pulses 82.67 81.50 0.00 59.20 13.19 9.22
.. Nuts 16.93 16.80 0.00 16.41 0.00 0.57
.. Spices 14.94 14.68 0.00 13.85 0.00 0.89

World diet:

Item Calories
Animal Products 514
.. Meat 273
.. Dairy 170
.. Eggs 36
.. Seafood 35
Vegetal Products 2371
.. Cereals 1292
.. Oils 331
.. Sugars 237
.. Roots 142
.. Fruits 98
.. Vegetables 96
.. Pulses 79
.. Drinks 75
.. Nuts 16
.. Other 5

References