“There is no country in the world in which people are satisfied with having barely enough to eat.� (Cohen 2005)
Michael Transue December 6, 2011 Science of Sustainability
Transue 1 "Human [population] numbers currently increase by 74 million to 76 million people annually, the equivalent of adding another U.S. to the world every four years” (Cohen 2005). The annual addition of approximately three-quarters of a billion people has allowed the current global population to reach 7 billion or so, and will facilitate far greater population growth in the future. Global projections indicate two important modifications in worldwide population that could potentially place a vice on humanity. The first is a significant upward shift in the populations of developing countries versus those in developed countries and the second is an increase in population density, as more individuals will remain in, or migrate to, urban areas. This increase in future populations will inevitably strain cropland and food production as starvation and malnourishment could become global issues for the world to combat. Newer, innovative technologies and techniques in farming, building design and city planning are necessary to alleviate the hardships of increased populations, especially urbanites of developing nations. Challenges are inherent in the development of inventive systems requiring collaboration of varying professionals, yet these innovations could provide manifold social, health and environmental benefits if implemented. “By 2050 the world’s population is projected to reach 9.1 billion,” however numbers could in fact be closer to 12 billion if global fertility rates remain constant (Cohen 2005). Regardless of the overall population in 2050, it is expected that a great portion will derive from poor regions as “[m]ore than 95% of the net increase in the global population will be in cities of the developing world” (Grimm 2008). Despite having higher death rates, developing populations will outnumber more developed populations six to one in 2050
Transue 2 due to the much higher birth rates those nations boast (Cohen 2008). In addition, the total urban populations of those developing nations was estimated at 1.97 billion by the UN Population Division in 2000, however that total is projected to increase to 3.9 billion by 2030 and an astounding 5.26 billion by 2050 (Montgomery 2008). “The world’s urban population as a whole is growing by just over 1 million people each week,” as 70% of the population is projected to live in urban areas in 2050 whereas only 30% were urbanized in 1950 (Brown 1998). Roughly 60% of this urban population growth is attributable to natural growth while the remaining 40% comprise of opportunity-seeking migration and spatial expansion (Montgomery 2008). “Together the world’s [7] billion people use land equal in size to South America to grow food and raise livestock—an astounding agricultural footprint” (Despommier 2009). To sufficiently feed a growing population reaching a modest projection of 9.5 billion in 2050, “civilization [would] have to cultivate another Brazil’s worth of land—[or] 2.1 billion acres” (Despommier 2009). Cropland expansion has been overwhelmed by the pace of human growth, as global population has grown seven times faster than grain area—“a proxy for cropland in general” (Brown 1998). It is likely this trend continues, creating environments where the availability of food would be scarce at best as countries would struggle to be self-sufficient in food production, “losing the capacity to feed themselves” (Brown 1998). “Some [experts] believe that the solution lies in even more intensive industrial farming, carried out by an ever decreasing number of highly mechanized farming consortia that grow crops having higher yields—a result of genetic modification and more powerful
Transue 3 agrochemicals” (Despommier 2009). However, strategic practices to “grow crops indoors, under rigorously controlled conditions, in vertical farms” are more responsible solution techniques (Despommier 2009). The current indoor agricultural technologies consist of three different types of growing methods: drip-irrigation, aeroponics, and hydroponics. Drip-irrigation farming utilizes shallow troughs filled with vermiculite or another reusable lightweight material instead of heavy soils; small tubes then slowly percolate nutrient rich water to the plant’s stem base. The practice of aeroponic agriculture enables plants to hang from fixed structures while their exposed root systems are infused with water vapor and nutrients, eliminating the necessity of soil. In hydroponic growing, the plants are fixed into soilless troughs while nutrients dissolved into water circulate around the plants (Despommier 2009). Small scale indoor urban agriculture projects in food barren locations can alleviate some regional burdens associated with population density increases; however the global food crisis requires worldwide recognition of the need to modify the current paradigm of urban living by infusing agricultural elements into the built environment, as vertical farms. “The [vertical farm] facilities could be the ‘playground’ for graduate students, research scientists and engineers to carry out the necessary trial-and-error tests” for the practical development of urban agricultural systems (Despommier 2009). It is estimated that a single 30-story vertical farm on one city block can sustain 50,000 people with vegetables, fruits, eggs and meats (Vogel 2008). On the upper floors, lighter aeroponic and hydroponic crops such as potatoes, tomatoes and berries could grow while lower floors would house larger crops like wheat and corn as well as waste-creating livestock. The
Transue 4 benefits of controlled vertical farms are manifold: “crops can be produced year-round, droughts and floods that often ruin entire harvests are avoided, yields are maximized because of ideal growing and ripening conditions, and human pathogens are minimized (Despommier 2009). Moreover, responsible design must incorporate integrated systems with sensitivity to environmental issues to ensure the facility meets a standard of sustainability on all facets. The ideal facility would recycle municipal wastewater for irrigation, incinerate solid wastes to create steam to power turbines, utilize renewable energy sources to power heat and lighting, and potentially turn human waste into plant food (Vogel 2008). Removing the strain on croplands with urban vertical farming contributes to the health of the land by allowing crop areas to “revert to [their] natural grassy or wooded states” (Despommier 2009). Moreover, eliminating the need for nitrogen fertilizers and minimizing fossil-fuel emissions from product transportation greatly reduces the impacts of traditional rural farming. No longer needing to meet the food demands of a growing population alone, farmers will not be forced to cultivate on ecologically vulnerable lands with depleted soils (Brown 1998). In effect, those lands could assist in maintaining our environment, rather than contributing to its devastation. “If half the urban infrastructure that will exist in the world in 2050 must be built in the [upcoming] years, the opportunity to design, construct, operate and maintain new cities [and the buildings in them] better than old ones is enormous, exciting and challenging” (Cohen 2008). Currently there is a universal understanding that “cities are concentrated centers of production, consumption, and waste disposal that drive land change” (Grimm
Transue 5 2008). Why can’t buildings also drive change while supplying humanity with required resources without stripping future generations the opportunity to thrive in the same environment? Therefore, “[i]t isn’t a matter of whether we think it would be nice to do urban farming or not… It’s a matter of whether we are going to survive” (Vogel 2008).
Transue 6 Works Cited Brown, L. R., et al. (1998) "Beyond Malthus: Sixteen Dimensions of the Population Problem," Worldwatch Paper 143, Worldwatch Institute. Cohen, J. E. (2005) "Human Population Grows Up", Scientific American, p. 48-55, September. Despommier, D. (2009) "The Rise of Vertical Farms," Scientific American, p. 80-87, November. Grimm, N. B., et al. (2008) "Global Change and the Ecology of Cities," Science 319:756760. Montgomery, M. R. (2008) "The Urban Transformation of the Developing World," Science 319:761-764. Vogel, G. (2008) "Upending the Traditional Farm," Science, 319:752-753.