The serious environmental problems that the world is currently facing are mainly caused by meat eating habit and over-farmed animals. Therefore, the transformation of livestock industry should be a priority for all countries. As long as we stop livestock farming and transform into growing vegetables, fruits and grains, most of the environmental problems will be solved easily. The content and data in this section are mainly quoted from the 2006 FAO report, Livestock’s Long Shadow. The main impacts of livestock are as follows:

Land Use
Livestock production accounts for 70% of global agricultural land, equivalent to 30% of the land surface of this planet. The total area occupied by grazing is equivalent to 26% of the ice-free terrestrial surface worldwide. To farm animals, 33% of total arable land is dedicated to feed-crop production. Livestock is also a key factor in deforestation, especially in Latin America. 70% of the Amazon’s forested land is occupied by pastures, and a large part of the rest is covered by feed-crops.
The land with a large number of animals will be compacted by the constant trampling of animals. This make the infiltrating capability of soil reduced and the groundwater level lower. The land will eventually degrade into a desert.
Water Pollution and Shortage
Livestock is also the main cause of water pollution and shortage. Freshwater resources are scarce on Earth, only 2.5%, because oceans accounts for 96.5% of water. Furthermore, the 2.5% freshwater resources have 70% locked up in glaciers, permafrost layer, and atmosphere. Most water reserves in the ocean (96.5%). Hence, more than 2.3 billion people live in water-stressed environments. Nevertheless, the livestock sector accounts for over 8% of global human water use, mostly for the irrigation of feed-crops.
In addition to using precious freshwater, livestock and related products (such as leather) produce wastes, chemical residue and manure. They also pollute water resources. Excessive nitrogen and phosphorus enter rivers and oceans, allowing algae and plankton to multiply rapidly. This reduces oxygen in water bodies (eutrophication) and forms coastal dead zones. The coral degrades and none of fish inhabits in these dead zones.
Biodiversity
Nature environment has variety of genes, species and ecosystems, which is biodiversity. It contributes a lot to human well being, such as providing healthy and safe space and basic materials for us to have a good life. However, the large number of livestock changes the nature ecosystem and climate. Habitats of species are destroyed in a great scale, and many species are on the verge of extinction.
The Millennium Ecosystem Assessment (MEA, 2005a) gauged that 1/3 of all amphibians, 1/5 of mammals and 1/8 of all birds are threatened by extinction based on known species. There are 90% or more of all existing species have not been cataloged yet excluded in the statistics. The number of extinct species in this range is unable to estimate.
Food Security
Livestock actually detract from the total food supply. They consume more human edible protein than produce. In fact, livestock worldwide consume 77 million tonnes of human edible protein contained in feedstuff. Whereas only 58 million tonnes of protein are contained in livestock meat products (FAO 2006). According to the latest statistics by Food and Agriculture Organization of United Nations (FAOSTAT 2020), almost 690 million people in the world were still undernourished because of hunger in 2019. Mainly in Asia and Africa.
Therefore, meat production cannot solve the food problem, but will only make the uneven distribution of food worse. The World Food Programme (WFP) warned in late 2020 that a major famine could break out in 2021 due to the epidemic lockdown. Famine would bring serious conflicts.
Climate and Atmosphere Pollution
The livestock sector is a major player that emits greenhouse gases, increases the temperature of Earth and causes climate change. This is one of the most serious environmental problems. The data in this book (Table 1-1) are cited from the United Nations Intergovernmental Panel on Climate Change (IPCC). And they differ slightly from the data in Livestock’s Long Shadow. This will be explained in detail in 1-3 to 1-4. In the non-greenhouse gas emission, livestock are also responsible for almost two-thirds (64%) of anthropogenic ammonia emissions. That acidifies the ecosystem and contributes significantly to acid rain.
Epidemics
Livestock products are more susceptible to pathogens than other food products. They transmit diseases from animals to humans, because many diseases are zoonotic. The World Organization for Animal Health (OIE) estimates that no less than 60% of human pathogens and 75% of recent emerging diseases are zoonotic. A series of human diseases have their known origins in animals, such as common influenza and small pox.
The process of livestock farming uses all kinds of veterinary medicines, like antibiotics, vaccines and growth promoters (hormones). Many microorganisms, parasites and drug residues are also contained in animal excrement. These stuff move into and pollute Earth’s ecosystems through water. Then they can be transmitted to human beings through drinking water and food. The dense animal population is also a hotbed for disease to transmit and mutate. Internal parasites are also mostly transmitted through consuming animal products.
The 7th annual meeting of Shanghai Science Association in 2009, director of the Immunobiology Institute in Fudan University, professor Xiong Sidong, straight talked that 100% of new diseases in recent years come from animals (Xinmin Evening News).
Conclusion
Countries are spending unbelievable amounts of money to deal with countless environmental problems and disasters. Nevertheless, the situation is not getting better but worse. The solution is actually very simple: just adopt a vegan diet policy and ban animal farming. The impacts of human meat eating choice and animal farming on the environment can be broadly categorized into the following 8 points:
1. Destroying Ecology of Environment
2. Desertification
3. Water Pollution and Shortage
4. Species Extinction
5. Foozd Shortage and Famine
6. Climate Warming
7. Epidemic Ravage
8. Huge Cost of Treasury

Further Reading: 1-3 Greenhouse Effect and Greenhouse Gases | 1-4 How Many Animals Are Slaughtered Worldwide Every Year?
Cited Reports: Livestock’s Long Shadow
Relative Download: Diet and Environment Relative Download