Agriculture as Conservation
Agriculture operates within a dichotomy – on one hand, it stands as among the most impactful and destructive practices undertaken by humans; on the other, it presents some of the most effective solutions for reversing climate change and biodiversity loss.
Out of Bounds
Scientists have identified 9 planetary boundaries which regulate the stability and resilience of the Earth’s ecological systems. Within each of these boundaries are a ‘safe operating space’ where life can thrive. Assessments show that six out of nine of these boundaries have been crossed to varying degrees. As we cross these boundaries, complex systems regulating Earth’s climatic and ecological conditions erode. Agriculture, and more specifically livestock production, is a leading cause in 7 out of 9 in surpassing these boundaries.
Image from Azote for Stockholm Resilience Centre, based on analysis in Richardson et al 2023
Climate Change
Agriculture is a leading cause of climate change worldwide. The majority of agricultural emissions are caused by livestock production. Numerous attempts have been made to estimate total global emissions from livestock alone, ranging from 12% estimations from the UN to 51% estimations from the Worldwatch Institute. While there is much debate about the contributions of agriculture and livestock to climate change, it is certain that addressing their outsized impacts will be critical.
Biosphere Integrity
Scientists have concluded that the boundary for biosphere integrity began faltering during the late 19th century. Today agriculture causes 70% of biodiversity loss around the world, largely due to habitat loss. Since 1970 there has been a 69% decrease in wildlife populations. Today only 2% of terrestrial mammals are wild, and livestock are so prevalent that they outweigh all wild mammals on Earth by a ratio of 15 to 1.
Land System Change
Large scale land system changes are extensively fueled by agricultural activity. Today agriculture occupies roughly half of all arable land globally and causes nearly 90% of global deforestation. Further broken down, livestock occupies 77% of all agricultural land while only providing 18% of global calories. Shifting from livestock production to plant-based agriculture alone could result in a reduction of 75% of agricultural land needs, or over a third of arable land around the world.
Freshwater Use
The planetary boundary for freshwater usage is 4,000 km³, a limit that was passed with a limit that was passed with a recent assessment of ‘green’ and ‘blue’ water usage worldwide. On average, agriculture accounts for 70% of global freshwater withdrawals. In the United States, 56% of freshwater usage is used just to grow feed for livestock production alone.
Novel Entities
Scientists found that “the safe operating space of the planetary boundary of novel entities is exceeded since annual production and releases are increasing at a pace that outstrips the global capacity for assessment and monitoring.” These entities include a range common agricultural products including novel pesticides, antibiotics, and genetically modified organisms.
Ocean Acidification
Ocean acidification, also known as climate change’s evil twin, is caused by increasing acidity in oceans due to changes in the carbon cycle. With roughly half of all greenhouse gasses absorbed into ocean systems, the pH of oceans is shifting towards unlivable levels for calcifying organisms such as corals and mussels, leading to many knock-on effects.
Biogeochemical Flows
Levels of phosphorus and nitrogen in the environment have increased dramatically due to agricultural practices. 75 of the 115 million tons of nitrogen and 14 of the 25 million tons of phosphorus applied worldwide are not utilized by crops and end up running into rivers, lakes, and natural environments. Excess nitrogen and phosphorus from fertilizers cause explosive growth of algae and large aquatic plants leading to decreased oxygen conditions called ‘dead zones’ where oxygen levels are so low no life can survive. The largest dead zone is in the Gulf of Mexico fed by the Mississippi River and ranges seasonally between 5,000km² to 22,000km².
Free Range Livestock?
Many around the world tout free range livestock as a solution to the environmental impacts of concentrated industrialized livestock production. A movement has manifested to label free range livestock production as regenerative and holistic. While this labeling has led many organizations and individuals towards free range products, the framing of free range livestock as regenerative requires closer examination.
Scientific studies attempting to evaluate the greenhouse emissions of free range vs industrialized livestock production have shown significant reductions of up to 66% – yet these reductions in emissions come with drastically increased land use requirements. The same studies show that to supply current amounts of animal protein from free-range sources would require 2.5 times the current landmass utilized for livestock. These added land use requirements are already driving deforestation around the world devastating already struggling wildlife populations by exacerbating habitat loss and mass extinction.
With added land use requirements, free range livestock is fueling deforestation around the world.
Photos from Dominican Republic.
Alternatively, a total shift to plant-based systems would free a landmass larger than China, Australia, the European Union, and the continental United States combined for conservation while completely eliminating greenhouse gas emissions from livestock production. While there are reductions in emissions relative to industrial livestock production and some increased levels of biodiversity in free range systems relative to the monocropped systems supplying industrial livestock – the opportunity costs of not transitioning completely from livestock to plant-based systems still lead towards mass extinction.
A Thought Experiment
100 Americans transition to plant-based
Agriculture is the perfect place to begin reducing inefficiencies because of its current impact on land usage. Today, agriculture occupies roughly 50% of all arable land around the world. Of the 51 million square kilometers used for agricultural production, 77% is for producing livestock, with the remainder occupied by crops grown for direct human consumption. In turn, the 37 million square kilometers used for meat and dairy production supplies a meager 18% of the global calorie supply, with the remaining 82% coming from plant-based sources.
In other words, less than 12% of habitable land supplies 82% of the global calorie supply. If we transitioned to entirely plant-based diets, we could conserve over 30% of all habitable land without reducing our ability to feed the world.
This transition offers a dual benefit: complete emission reduction from livestock production and additional gains from carbon sequestration through rewilding and reforestation efforts. This strategy could reduce global greenhouse gas emissions by a minimum of 30%, helping avert the ongoing global ecological crisis.
Image and sources from page 12 of the RAÍCES Institute Report
To learn more about the connections between the food system and the environment, we recommend the books Regenesis by George Monbiot and Food Choice and Sustainability: Why Buying Local, Eating Less Meat, and Taking Baby Steps Won't Work by Richard Oppenlander.
