A Comparison of the Sustainability of Meat-Based Diets and Plant-Based Diets
Wessal Kenaio BeamReach Marine Science and Sustainability School 10/25/2007
Sustainability is characteristic of a practice or state that can be maintained at a certain level for an indefinite period (Wikipedia). This definition has broad implications as it relates to meat farming. In short, it means that a sustainable meat farm should be able to produce meat for an indefinite period without causing permanent damage to ecosystem health. In a broader sense, it also refers to secondary effects of non-natural meat farming caused by added hormones, degraded meat value, and the quality of life of the animals being farmed. For farms that feed their animals grain, sustainability also includes production of the grains necessary to feed the animals (or not feeding them grains at all). This article is an investigation into the sustainability of meat products. It considers whether it is possible to consume meat in a sustainable manner and briefly compares the sustainability of meat to other vegetarian options such as dairy and eggs. Finally, it offers suggestions for sustainable farming methods.
In our fast paced, high population society, emphasis is often placed on eating quick, affordable meals. Unfortunately, the options associated with such dining are not always the best for our ecosystem, or our health. Over the past century, farming has become an effort which makes the words “mass production” seem trivial. High volumes of food are being produced in the cheapest possible ways. Ways that are proving detrimental to our earth. Genetically modified plants and animals have been manipulated to challenge millions of years of evolution. This combined with unnatural supplements of growth hormones and antibiotics, has agricultural animals and plants growing at alarming rates. We are using thousands of years worth of stored fossil fuel resources and adding unusual chemicals and nutrients into the environment. It is no surprise that our global ecosystem has not been able to healthily keep up with our expanding population and expanding demand for food.
In light of global warming, environmental scientists and the general public alike are becoming more and more aware of the damage industrialization is having on our earth. Conservation efforts are growing to attempt to halt and possibly reverse the effects of 150 years of burning of fossil fuels. With the advent of the tractor-trailer and increasing US demands for food, agricultural farming has become a major contributing factor to global warming. Unprecedented resources have been and are currently being put into the production of our food, including limited land, water, and fossil fuel resources. The US agricultural industry requires unprecedented fossil fuel energy. Current US food production uses 50% of total domestic land area, 80% of fresh water, and 17% of fossil fuels (Pimentel et al). Fossil fuel energy input versus protein produced for animal protein in the US are as follows:
|Livestock and animal products Ratio of energy input to protein output|
Table 1 The fossil fuel energy input required to produce 1 kcal of animal protein (Pimentel et al)
Table 2 demonstrates the grain and forage inputs per kilogram of animal protein produced (Pimentel et al.). This means that to produce 1 kg of lamb protein, 21 kg of grain and 30 kg of forage product (grass) were consumed. If grain-fed animals were fed on good-quality pasture alone, energy inputs would be reduced by approximately half, as farmers would not be relying on fossil fuels to help grow and transport grains.
|Livestock||Grain (kg)||Forage (kg)|
Table 2 Grain and forage inputs per kilogram of animal protein produced (Pimentel et al)
If we want to preserve our earth for our future generations, we must begin to take steps to ensure more efficient methods of producing our sustenance. A question now arises: Is it possible to produce nourishment in manners that are completely sustainable? And if not, how can we maximize efficiency with regard and respect for our planet simultaneously?
From an ecological perspective, agriculture can be defined as the practice of capturing solar energy, as converted to plants (or animals after consumption of those plants) and transferring that energy to people for their use (Heitschmidt et al 1996). Agricultural efficiency is the business of capturing solar energy and transferring it across trophic levels. Primary producers are those organisms (i.e. plants) which capture the energy of sunlight directly. They represent the bottom and first trophic level significant to agriculture. Primary consumers are cattle, chicken, pigs, and other animals associated with agriculture, whether it is for direct consumption of meat, or consumption of secondary products such as dairy and eggs, represent the second tier in trophic level. Finally, humans (and pets) represent the third tier in this agricultural hierarchy (Heitschmidt et al 1996). We are secondary consumers because we consume plants and animals from the previous two tiers. A food chain is the interaction of these levels. It is through the food chain that energy is converted from solar energy and transferred among different species on different levels. (Heitschmidt et al 1996).
Most agricultural production today is done in the most affordable way possible. Respect is given to the quantity of food produced, not quality. Farming on a mass scale has been proven to be detrimental to our ecosystem. According to eatwild.com, mass farming results in: the introduction of large quantities of pesticides into the ecosystem, topsoil erosion, aquifer depletion, reduced genetic diversity, addition of fertilizers to soil, hormone residue, antibiotic residue, and the list goes on.
The current methods of agricultural meat production allow farmers to produce more animals than their land is naturally capable of maintaining. Farms where animals graze off the land for their nutrients are inherently more sustainable as they can only support the number of animals that the land could provide for naturally. A study done by Heitschmidt et al (2004) considers the sustainability of rangeland agriculture (managed grazing). His paper suggests that managed grazing is sustainable as an option for growing animal protein on ecological, economic, and social levels. He suggests that there are four areas to consider regarding the ecological sustainability of rangeland meat production:
- Defoliation of plants
- Trampling and treading of surfaces
- Fecal and urine defecations
- Atmospheric gas changes
Selective defoliation can alter competitive relationships and cause shifts in plant distribution. This can result in the proliferation of less productive and desirable plant species. The trampling of topsoil results in less roots and plant matter to absorb water and particles. This in turn causes an increase in surface water runoff and sediment production. The addition of nutrients via fecal and urine deposits alters natural nutrient cycles for the positive or negative. Finally livestock may be responsible for 15% of the worlds output of methane (CH4) (Heitschmidt et al 2004).
Nevertheless, with proper rangeland management strategies, meat production as a product of grazing is a sustainable option (Heitschmidt). The following strategies could be considered and implemented to develop meat products sustainably:
- The need to balance efficiency of solar energy capture and harvest efficiency
- The inherent range in abiotic growing conditions over time and space (ex: seasonal and annual droughts which alter primary production)
- Managing the impacts of selective grazing
To meet the above challenges, a number of tactics have been used to ensure that rangelands are properly grazed: proper stocking rates, strategic herding, fencing, water development, and various grazing systems (Heitschmidt et al 2004).
Limitations of controlled grazing efforts do exist however. Economic returns prohibit employing high-cost, ecologically ameliorating management tactics (Heitschmidt 2004). There are ecological threats to sustaining rangelands as well. The invasion of noxious plants is one such threat. The continued conversion of rangeland into land for other uses such as cropland or homesteads is also a continuing threat. Finally, rangeland can be subject to desertification (primarily because of soil erosion) (Heitschmidt 2004).
The social and economic sustainability of rangeland agriculture are strictly dependent on the beliefs of the society. Economic practicality in particular is dependent upon the beliefs of the society at any instant (Heitschmidt et al 2004). Despite the fact that rangeland agriculture is one of the oldest and most natural forms of agriculture known to man, general perception is that it is not environmentally appropriate (Heitschmidt et al 2004). This in turn reflects societal decisions, including those to buy meat produced on natural rangeland.
As outlined by the United States Department of Agriculture’s Sustainable Agriculture and Research Education (USDA’s SARE) program to promote sustainability on farms, farmers can take several steps to farm more efficiently and sustainably. The first is in regards to the control of pests. In the past several decades pests have primarily been controlled by chemical methods. SARE’s Integrated Pest Management (IPM) combines biological, cultural, physical, and chemical tools to control pests in an environmentally friendly, economical way. Rotational grazing is also a management strategy employed to reduce manure buildup and reduce reliance on grains as feed. (SARE).
SUSTAINABILITY AND BEAMREACH
Beam Reach is a school devoted to Marine Science and Sustainability. It is a forward thinking program that is devoted to teaching students about the importance of conscience decision making as related to sustainability. As stated previously in this paper, our earth’s resources are rapidly diminishing, as simultaneously is its health. In order to ensure a healthy ecosystem for generations to come it is up to us to promote healthy ways of living for ourselves and our children. Aside from teaching these concepts, Beam Reach takes active steps to practice them. This paper is focused on agriculture and primarily animal-product agriculture in the United States. In order to reduce the impact we have on our ecosystem, Beam Reach has adopted a policy of not consuming meat for sea portions of the program. As previously mentioned the production of a meat-based diet requires more energy than a vegetarian based diet. As such, while participating in the sea-based part of the program, each individual involved is impacting the ecosystem in a way that is less harmful than the average person.
Consuming or not consuming meat is only part of the puzzle when it comes to ecosystem health. As meat is primarily produced today, it is a very unsustainable product; however, as defined above, it can be produced, and incorporated into one's diet sustainably. Whether or not Beam Reach does incorporate sustainable meat products into the diets of individuals involved in the program, there are steps Beam Reach can take to make the diet aspect of the program a more sustainable one. For example, Beam Reach has made a conscious effort to buy the majority of its food from locally grown organic farms. This ensures less of a carbon footprint to get goods to the program; it also ensures a higher quality product, which undoubtedly has less of an impact on the ecosystem. Nevertheless, much of the food Beam Reach purchases is already processed food that has traveled a long way to make it to the Beam Reach table. This purchase of pre-packaged processed foods was most often made to save on time or budget. To increase sustainability Beam Reach should make more of an effort to make a higher proportion of the diet fresh, local food options. As a new program, Beam Reach is just starting to define what it is and what it stands for. The fact alone that it cares enough about sustainability to incorporate it into the curriculum shows that the effort and desire to be a sustainable program are already present. Tweaking the details will come with time, and I look forward to seeing what Beam Reach becomes in the years to come.
“Properly managed grazing is ecologically sustainable” (Heitschmidt et al). The greatest challenge associated with rangeland grazing as a continued source of animal protein is the social values of our culture. The biggest threat to our ecosystem is the growing, unsustainable human population. To stop the degradation of our ecosystem we will first need to control the rate at which our population continues to increase. That is the bottom line. Our earth is clearly not in a healthy state. We need to stop the use of un-renewable, damaging resources and convert our industrialized lives into those that are clean, renewable, and sustainable. Only then will the earth begin to heal and become a healthy place for our children and grandchildren to live for generations to come.
Exploring Sustainability in Agriculture. Brochure developed by the USDA’s Sustainable Agriculture Research and Education. www.sare.org or (301)-504-5230
Heitschmidt, R.K., Short, R.E., Grings, E.E. 1996. Ecosystems, Sustainability, and Animal Agriculture. Journal of Animal Science 74. 1395-1405
Heitschmidt, R.K., Vermeire, L.T., Grings, E.E. 2004. Is Rangeland Agriculture Sustainable? Journal of Animal Science 82. E138-E146
Pimentel D., Pimentel M. 2003. Sustainability of meat-based and plant-based diets and the environment. American Journal of Clinical Nutrition 78. 660-663