Tragedy of the Commons? Resource Scarcity Caused by Feeding the World by Brenna Broderick

Transitions for Sustainability, Vol. 2, No. 4

Introduction

Growing global populations result in rising global food demand. The past century has seen a rise in industrialization across food production, paralleling globalization and population growth. Agricultural intensification practices have been successful in trying to reduce inefficiencies and improve yields. However, with climate change putting arable land at risk and population growth projections showing steep and constant growth, the challenge of feeding the world is an uphill battle. The future of food systems must not only assess how much crops we grow, but rather what crops we grow, why we are growing those crops, and what we can do to preserve resources needed for agricultural prosperity.

The industrialization of the livestock industry has significantly increased the scale of output or livestock products (Lazarus et al., 2021). However, traditional livestock production methods are resource-intensive, contributing to land use change and deforestation, greenhouse gas emissions, and water scarcity (Md Nasir et al., 2022). As a result, livestock production has put stress on natural resources such as land and water, which are already made vulnerable by climate change and global warming. Meeting the demand for increased livestock production with sustainable practices will require innovative, creative and industry-wide evolutions to animal nutrition. This analysis will seek to outline challenges posed against global livestock production and propose an array of market solutions, taking into account the challenges and opportunities for implementation.

Background

Livestock Production Data

Global meat production has astronomically increased since 1960, from 72 million tons to 356 million tons (MT) (Ritchie et al., 2017). While marginal increases can be seen in other producing countries, including India, the U.K., and Brazil, the most significant increases were in the U.S., which grew from 16 MT to 49 MT, and in China, which grew from 2 MT to 92 MT (Ritchie et al., 2017).

The increase in production since 1960 is in alignment with increases in production scale by livestock type, as seen in Figure 1 (Ritchie et al., 2017) . Poultry increased from 9 MT to 136 MT, swine increased from 26 MT to 124 MT, and beef increased from 30 MT to 79 MT (Ritchie et al., 2017). This increase in beef production occurred dominantly in the US, where production more than doubled since 1960 (Knight, 2023).

Figure 1

Global Meat Production by Livestock Type, 1961 to 2021

Climate Change & Agriculture

Climate change compromises agricultural productivity by negatively impacting both water access and land quality (Richter et al., 2020). Consistently higher temperatures increase evapotranspiration, the loss of water during the process of plant growth due to evaporation, which will result in increased irrigation demands in coming decades (Richter et al., 2020). Crops that had previously been irrigated with less water will require more, causing irrigation inefficiency and higher water loss in agricultural production. As demands from irrigation put stress on surface and groundwater, changes in climate such as heat waves, droughts, and decreased rainfall will reduce precipitative availability and deepen dependance on irrigation water.

Climate change threatens the reliability of water sources, making water preservation critically important. Global warming changes terrains and climates, putting some regions of arable land at risk of becoming too dry or arid to continue supporting agriculture. This will reduce overall available arable land globally and lead to increased deforestation, which releases carbon emissions and accelerates warming through greenhouse gas trapped in the atmosphere (Wirsenius et al., 2010). The result is a positive feedback loop in which global warming and the expansion of livestock production have a causal relationship with each other (Van Zanten et al., 2018).

Population Projection Data

According to the UN, the global population is projected to rise by 2 billion people in the next 30 years, reaching 9.7 billion in 2050. To meet rising demands, global food production will need to double by 2050, thus food production through agricultural industries is expected to increase by approximately 60% and meat production is projected to rise by nearly 70% (Dineshbabu et al., 2019).

Protein Efficiency

Several factors influence the resources used to sustain livestock from birth to production, including life cycle, diet and weight. Disproportionately, beef cattle have the most intensive resource requirements because their size and lifespan require higher amounts of feed for a longer period of time (de Vries & de Boer, 2010).

Land and Feed

The amount of land required for beef cattle production can be measured as 164 square meters per 100 grams of protein produced, or a ratio of 164:100. This compares to a land use ratio for swine of 10:100 and for poultry of 7:100 (Ritchie et al., 2017). As a whole, an average beef cow produces 270 kilograms of beef product, which translates to 440,150 square meters, or just over 10 acres, of land required for feed production for one cow (Hoekstra, 2012).

Livestock land ratio depends upon their feed consumption needs. To produce 1 kilogram of product, beef requires 25 kilograms of feed or a ratio of 25:1. This is significantly higher than swine at a ratio of 6:1, and poultry at a ratio of 3:1 (Ritchie et al., 2017).

Water Footprint

Water used in livestock production can be understood using the consumptive water use ratio (CWU), which accounts for the water consumed by feed grown for production. FOr beef cattle, the CWU ratio is 112 liters of water per gram of protein (112:1), compared to poultry at 34:1 and swine at 57:1 (Hoekstra, 2012).

Protein Conversion Rate

Another important factor to consider is the proportion of protein consumed in feed to protein produced in meat product. Cattle have a protein conversion rate of 4%, meaning the rate of feed protein input that is effectively converted to beef product protein output. The remaining 94% of feed protein is lost (Ritchie et al., 2017). Swine and poultry have a protein conversion rate of 50%. This means that half of the protein that swine and poultry consume is lost, or that they consume two times more feed protein than they produce for human consumption (Van Zanten et al., 2018).

Livestock Production Resource Use

Land Use

Through agricultural feed growth and pasture-grazing, livestock use accounts for about 70% of global agricultural land (Van Zanten et al., 2018). This has not always been the case and a correlation can be seen between land conversion over the past century and the steep increase in livestock production from 1960 through current day.

After 1960, livestock production increased by over 500% in tonnage. During the same timeframe, global land-use change increased by 43 million square kilometers, accounting for nearly one third of the earth’s total land area (Viglione, 2021). While urbanization and spatial population expansions can account for much of this land-use change, nearly a quarter of it was due to deforestation for agricultural expansion (Viglione, 2021).

Livestock agriculture accounts for 70% of global agricultural land, making it a key driver of deforestation in recent decades. (Van Zanten et al., 2018). Land use by livestock agriculture is significantly higher than land use for human consumption crops; furthermore, it’s expected to double by 2050 due to projected population increases (Ran et al., 2017). To meet this demand, competition will increase between feed and food and threaten remaining available arable land, which is not sufficient for increased food projections, causing continued deforestation for agricultural expansion.

Water Use

Agriculture accounts for 90% of humanity’s freshwater use and nearly one third is attributed to livestock agriculture and production (Gerbens-Leenes et al., 2013). Freshwater use is nuanced. It includes green water, water from precipitation, and blue water, irrigation water drawn from groundwater or surface water (Gerbens-Leenes et al., 2013). Green water use has a lower environmental footprint, however can be unpredictable due to risks posed by climate change, droughts, and extreme weather events (Ran et al., 2017). Blue water is the dominant water consumptive use of livestock feed, which uses intensively irrigated animal feed.

Feeding practices vary among leading livestock producers. Brazil uses pasture grazing as its primary practice, which is dependent upon green water and arable land acreage for grazing (Schlink et al., 2010). China and the US both use feed production more than pasture grazing (Schlink et al., 2010). Because highly irrigated feed crops put demand on ground and surface water sources, industrial production systems have a high water footprint of blue water.

Livestock agriculture produces intensively irrigated crops and thus, is the sole largest global consumptive water user (Richter et al., 2020). In the US, western states produce 99% of livestock feed in the country, as well as more than 90% of cattle meat consumed in the US (Richter et al., 2020). In these states, hydrologic modeling shows that livestock agricultural irrigation is the most significant cause of depletion in nearly half of all surface water (Richter et al., 2020).

The distinction between green and blue water consumption is relevant as the hydrological, environmental and social implications, in addition to economic value, of ground and surface water differ from those of precipitation water use (Gerbens-Leenes et al., 2013). Water scarcity is more likely to be caused by excessive withdrawal from surface and groundwater for irrigation than by reduced rainfall or droughts (Lin et al., 2021).

Water is a finite resource. Consumptive water use being dominated by livestock agriculture leaves a fraction for all remaining sectors, including agriculture for human consumption, which might produce more resource-efficient plant-based protein, as well as energy or sanitation use.

Discussion of Solutions

While livestock products are culturally and socially common as a source of dietary protein, the plant protein input to animal protein output rate is highly inefficient. Using irrigated, arable land to produce livestock feed is much more land-intensive and water-intensive than it would be to use the resources to produce plant-based protein agriculture (Van Zanten et al., 2018). The inefficient livestock protein conversion rate is incongruous with the scale of livestock products as a dominant dietary component. Furthermore, it raises doubt about the inclusion of livestock products in a sustainable diet, considering the environmental, economic, and sociological impacts on land and water. Aligning the burden on resources of livestock agriculture with projected population growth, it becomes clear that livestock production cannot continue as business-as-usual if we are to feed a growing world with finite resources.

The most obvious solution feels a bit like the elephant in the room: we need to be eating less meat. This is among an array of behavioral changes that could help move the needle. As the resource footprint for poultry and swine are less than half of that of beef, and with exponentially higher protein conversion rates, one solution would be a social and cultural dietary shift away from red meat (Md Nasir et al., 2022). This solution offers a compromise between asking the world to go plant-based or allowing it to continue as is. Furthermore, the alternate protein market is making encouraging progress integrating into the mainstream (see the Impossible Whopper), creating well-received substitutes for beef protein. While behavioral changes are a key influencer of production changes, these are not the solutions that this analysis will seek to explore and recommend.

In order to instill sustainability practices into the resource footprint of livestock products, changes need to be made to that which requires most land and water: feed. The recognition that traditional feed production methods are resource-intensive, and that those resources would be more efficiently used for the production of human consumption crops, has been a fairly recent one. Research into alternate types of animal feed remains simply that: research, and to date, there has yet to be a mainstream market of large-scale feed alternates. However, the research shows diverse and encouraging potential.

Alternate Livestock Feeds

Algae

Benefits. Algal organisms and plant life are recommended as animal feed ingredients or supplements due to their high protein and nutrient-rich compounds. As feed components, they are useful in mitigating the environmental impact of livestock with minimal greenhouse gas emissions and land requirements (Md Nasir et al., 2022).

Perhaps the longest researched area of alternate feed, microalgae have long been known for their diverse nutritional properties. Microalgae are fast growing, microscopic, photosynthetic organisms that grow in aerated, liquid environments (Dineshbabu et al., 2019). They are also nutrient-rich, with higher  protein, omega 3 fatty acids and carotenoids content than traditional sources of animal feed, such as millet or grains. Apart from being nutritious, they have anti-oxidative, antimicrobial and disease-preventing molecules that can provide long life span to livestock (Dineshbabu et al., 2019).

Azolla is a free-floating water fern being researched for animal feed because of its high content of proteins, fatty acids, amino acids and vitamins (Md Nasir et al., 2022). Due to its nutrient-rich profile, azolla has been used successfully as a fertilizer agent in rice paddies. Similar to microalgae, azolla has also shown anti-oxidative properties that can improve the lifespan of livestock.

Challenges. The main challenge of translating the nutrition of algal organisms and plantlife into animal feed is scaling up production with the correct growth conditions while maintaining biomass productivity and optimal nutrient compounds. This is an ongoing area of research, showing encouraging progress and potential.

Crop residue & by-products

Benefits. After harvesting crops, residues often remain that can be used for feeding livestock, including regrowth, shelled grains, or stubble residue from where crops are cut (Lardy et al., 2022). The easiest way to turn this into animal feed is in areas where livestock, typically cattle, can directly graze from it. In cases where sufficient crop matter remains, such as soy or corn crops, baling is also an option however can be expensive due to additional labor and supplies (Alternative Feeds Beef Research, 2023). For this reason, crop residue is usually a recommendation for smaller farms or farming communities rather than commercial feed systems.

Challenges. As noted, this option makes more sense for cattle grazing in small farms or farming communities. The expense of harvesting crop residue makes it an inefficient commercial feed production option. Furthermore, it is necessary for livestock farmers to know the protein and nutrient content in the feed their livestock consume, so to ensure consistency in life cycles and products (Alternative Feeds Beef Research, 2023). Calculating the nutrition value of crop residue is extremely difficult, making it a less attractive option of commercial livestock production.

Fruit and vegetable discards & by-products

Benefits. After harvest, fruit and vegetable products are culled, which is the process of sorting freshly harvested produce into saleable lots, with saleable  lots being discarded or diverted to non-food processing activities. Produce that is culled is usually damaged or showing signs of quality deterioration (Alternative Feeds Beef Research, 2023). Fruit and vegetable byproducts are also produced in food processing, typically scraps, leftovers, or unusable parts, and typically go directly to food waste. While fruits and vegetables are typically low in protein, they can be high in energy, starch and carbohydrates, making them a high-volume replacement for grains (Alternative Feeds Beef Research, 2023). Depending on regional availability, culled fruits and vegetables can be a highly cost-effective way to add nutritional content to feed rations (Lardy et al., 2022). A significant benefit of using culled produce or produce byproducts is the reduction of resource requirements. Agricultural land and irrigated water would no longer compete with that which is for agriculture for human consumption, and food waste could be reduced by feeding livestock discarded food for human consumption.

Challenges. There are several challenges to using culled produce or fruit and vegetable byproducts. As these are high-moisture and perishable foods, they risk spoiling quickly. Due to this, they are most useful as regional feed additives and cannot easily be commercially processed and shipped as feedstock (Alternative Feeds Beef Research, 2023). Furthermore, due to the low-protein and fiber content, they cannot act as standalone animal feed and require supplementing ingredients or feedstock to be nutrient-rich enough for high-protein livestock such as cattle.

Insects

Benefits. The recommendation of insects for livestock feed is biologically sensible as many animals naturally eat insects as part of their diet. Insect meal contains up to 76% crude protein and nutritionally important amino acids, as well as high-amounts of B12, which aids in nutrient absorption, and antimicrobial peptides, which are vital for immunity and reduce the need for antibiotic additives (IPIFF, 2021). Due to their high protein, insects are far more resource-efficient sources of protein output per land requirement than other feedstock. Their fast development, allowing for several lifecycles of insects produced per year, make insects 70 times more efficient than traditional vegetal feed (IPIFF, 2021).  Furthermore, insects can be fed using human food waste, reducing food waste by returning it back into the food cycle. This contributes to insects being an environmental alternative to animal feed, as the land and water resources that have been dedicated to growing livestock feed could be converted to growing food for human consumption, and waste from human food could be fed to the insects that feed livestock (Loeb, 2018). Reducing stress of land and water resources would reduce deforestation which, in hand with the minimal greenhouse gas emissions produced from producing insects, would significantly reduce the carbon footprint of agricultural production.

Challenges. Similar to algal feed, the main challenge of farming insects as animal feed is scaling up production while maintaining nutritional value and insect health. Specifically, protecting against novel or unknown diseases that could be spread to livestock or to humans from insects is an important aspect of this feed alternative that is currently undergoing research  (IPIFF, 2021). Secondly, gauging social and cultural response to consuming insect-fed products may require careful marketing and targeting.

Barriers to Implementation

It is important to note that while the emergence of alternative feed would reduce the need for resource-intensive livestock feed such as alfalfa, soybean, grain, corn, and forage crops, and thus result in more land and water resource available for crops for human consumption, the shift away from growing feed crops would have significant impacts.

For some regions, dry or arid climates have created soil not suitable for many crops. Forage crops, such as alfalfa hay or bermudagrass, are tough, resilient crops that have created thriving agricultural economies in regions which may have otherwise had inconsistent or fledgling crop yields. This is the case in the Imperial Valley in southern California, where the arid climate and low-moisture soil can have volatile effects on crop yields year to year (Udall & Peterson, 2017). As a result, alfalfa and bermudagrass have become the most commonly grown, due to their consistent yields, high demand, and profitability. Corn is another example of livestock feed fueling the American agricultural economy. Despite less than 1% of corn being sweet corn consumed in its unprocessed form, corn is the most subsidized and abundantly grown crop (O’Neill Hayes & Kerska, 2021). Of the remaining 99%, more than half of corn used domestically is made into animal feed (O’Neill Hayes & Kerska, 2021).

A serious concern of switching to animal feed alternatives is the potential economic collapse of the animal agriculture industry, if not swiftly repurposed or redesigned. While examples provided spoke to this in the US, it would be a global issue as feed is commercially produced and traded globally. A solution to this would be a slow and strategic transition from animal agriculture to crops from human consumption, supplementing along the way with alternative feed options. This would help avoid economic collapse, while reducing over time the stress on resources caused by animal agriculture.

Conclusion

Overall, global food production cannot continue business-as-usual. Arable agricultural land is going to continue decreasing due to warming temperatures making for drier conditions and poor soil quality, as well as natural disasters which decimate land quality. Freshwater sources such as rivers, lakes, and groundwater are put at risk by warming, droughts, and floods (de Vries & de Boer, 2010). While resources needed for agricultural production decrease, demand is expected to continue to increase due to steep population growth projections. Increasing food demand without increasing land and water to produce it will lead to intense competition and an increase in prices, and eventually inequality and conflict (Davis et al., 2016). Innovative industry changes are necessary to ensure land and water are utilized efficiently to produce as much food for human consumption as possible.

As noted, animal agriculture is a significant user of both global arable land and irrigated water, driving vast land use change and deforestation across the past century and causing water scarcity. Livestock, specifically beef cattle, have a disproportionately high land and water footprint to other crops grown for human consumption, and a significantly lower protein conversion rate, meaning they consume more protein they produce (Ritchie et al., 2017). Thus, the plant protein grown for animal feed would be more efficient if produced directly for human consumption.

This premise leads to the aforementioned recommendation: if we are to reduce the environmental impacts of livestock without calling for significant behavioral changes, such as the cessation of beef consumption or the transition to market meat alternatives, changes must be made to the means of production which require the most resources. Instead of changing what we eat, we can change what our food eats.

As noted, the field of livestock feed alternatives is relatively recent, with most research being conducted in the past five to ten years. Because of this, the livestock feed industry has not experienced mainstream shifts to alternatives or the presence of feed alternative products. This makes this area a market ripe for investment, innovation, and entrepreneurial emergence. Also, as noted, the switch away from livestock agriculture could put many regional, national and global markets at risk of collapse, and so a slow and deliberate transition away from animal agriculture alongside the growth of an alternative feed industry is an important stipulation of this recommendation.

Transitioning to one, or more likely, a combination of, the outlined feed alternatives opens up a wealth of potential for environmental preservation and climate improvements. By reducing traditional agricultural feed growth, the amount of land and water needed for animal agriculture could be allotted to growing crops for human consumption, aligning production with projected demand (Harris, 2021). Furthermore, it would remove market competition between animal agriculture and human-consumption agriculture, reducing environmentally harmful impacts and contributing to overall climate and human prosperity. In this way, this issue is a near direct modern day embodiment of the tragedy of the commons allegory. While it is debated if the famous allegory can truly be solved or overcome, I would argue that this example demonstrates the market innovation that is prompted by resources put under stress. The concern remaining is if innovative feed alternatives are able to grow quickly enough into a robust industry able to meet global demand, in order to preserve agricultural land and freshwater, reduce carbon emissions, and contribute to a more sustainable global food system.

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