Photo 1: An array of vegetables and fruits photographed by Enric Archivell, shared on Flickr and part of Creative Commons.
The amount of energy necessary to supply the entire process poses a problem in the current global agricultural system. Fossil fuels are necessary to provide energy for many stages of the system, from energy used “directly for tillage and crop management or through the application of energy-intensive inputs e.g. nitrogen fertilizer and pesticides…[as well as] energy in tractors, buildings and other infrastructure” (Woods). These cannot be simply cut back on, as it has become “necessary to support agriculture and food supplies…as developing agricultural producers invest in the infrastructure needed to increase yields and become competitive in the global food commodity markets” (Woods). When fossil fuels and energy usage first became a concern, processes including farming were intently measured to ensure efficiency and yield amount versus input amount. Many times, no problems arose due to the high energy yield and high utility of the crops, but more recent studies have found that, “over the full life cycle of a crop, particularly where energy-intensive drying and processing are required, in some cases more fossil energy can be used than is contained in the final product” (Woods).
Photo 2: A crop harvester photographed by the Scania Group shared through Flickr and part of the Creative Commons
It must be noted, however, that each crop and individual agricultural process’ energy amount and type required varies, and comparing measurements proves complex since “each agricultural product has very different properties and uses, making comparisons using a single metric problematic” (Woods). Though difficult to directly parallel them, the system clearly requires a very large amount of energy, which can hopefully change in coming years because the global system may face substantial issues if the input continues to exceed the yield.
The negative environmental effects pose another issue that causes a need to reevaluate the intensive farming system. The greenhouses gases (abbreviated GHG) emitted in the farming process itself, especially through the synthesized biological processes necessary to the growing of crops, give off emissions that are harmful to the environment because they damage the ozone layer and lead to global warming and harmful rays being released into the earth’s atmosphere. The levels of greenhouses gases especially stand out in the nitrogen fixation process, performed agriculturally through the perfected Bosch-Haber Process. This process produces usable nitrogen synthetically, similar to the way plants fix nitrogen naturally. After the process was discovered, it has become more and more widespread and now accounts for around 1/3 of the world’s population’s food supply (Clark). However, as “global nitrogen fertilizer applications have increased more than sixfold over the past 40 years,…there has been considerable regional variation. The production of mineral and synthetic fertilizers, especially nitrogen using the Haber–Bosch Process, uses large amounts of fossil energy, mainly natural gas, releasing…[a lot of] carbon dioxide into the atmosphere each year” (Woods). The process used to create fertilizers enhances crops’ quality, quantity, and speed of production so that more production can occur and therefore more people, worldwide, can be sustained.
Photo 3: A clear sky above an agricultural piece of land photographed by Pat Dalton, shared on Flickr, and part of the Creative Commons.
Like energy input levels, detrimental emissions also prove difficult to measure and compare, as, “differences in farming techniques, levels of mechanization, scales of production and soil and weather conditions in different regions make it difficult to quantify total fossil energy use and to extrapolate data from one agricultural system to another” (Woods). Again similar to the energy levels, overall the system clearly gives off very high greenhouse gas levels that cause environmental damage, and therefore researches are working to find alternative systems that include lower negative effects to the atmosphere.
As each of these problems have arisen, people have done work to suggest a variety ways to tweak the agricultural system, so that production levels stay the same or even improve, but still take into account the energy levels and environmental effects. One simple idea proposed to address the nitrogen fixation-related issues suggests a reduction in fertilizers. However, “although fertilizer manufacture is energy-intensive, reducing fertilizer use has mixed effects…a very large reduction in N [nitrogen] application can cause sufficient yield loss that cultivation becomes the dominant energy demand and energy use per tonne increases again” (Woods). There are always drawbacks to a situation, but here it seems that the solution cannot be as simple as cutting back or disregarding the yield. After all, this is the global population’s food we’re talking about.
Biomass, an energy source that can often be used in substitute for Carbon and other nonrenewable energy sources, is often advocated as a resolution to the energy input problem. One author states that the answer lies in, “the growth of microalgae for biofuel production…[and] supplying external, synthetic nitrogen may produce significant reductions in net energy gains and also result in competition for fertilizer with food producers” (Peccia). In these systems, one often must start at the smallest production level to make a change that will affect the entire system, hopefully for the better. One author, Bouwman, takes the idea further, recommending a carbon tax, so that consumers would be encouraged to buy the cheaper, better (as far as energy levels and emissions go) option of biofuels. Many developers’ focus remain on the nitrogen fixation issue, and show determination to find a way for the system to run that is all-around superior for the betterment of the world’s system as a whole.
However, systems other than simply a very small but impactful energy type change can help solve the issues arising with energy levels and environmental problems. Simply changing the protocol for the use of the land can help address the complications. For example, “alternative methods of land preparation and crop establishment have been devised to reduce energy requirements and maintain good soil structure. These include minimum tillage (min-till), conservation tillage (no tillage or min-till) and direct drilling resulting in increased surface organic matter from previous crops residues” (Bouwman).
In addition to individual fields and farmers changing their techniques, the global system can change the regions and types of space used to spread out the practices, instead of condensing them into small areas. This would allow for more natural processes to be used, meaning less human synthesizing and unnatural sources would remain necessary. This idea, however, “requires global cooperation,” which, while idyllic, may be an unreasonable assumption due to the many conflicts in the world. World leader have fought over issues of food and subsistence for decades, and will continue to be an issue while still scarce, which, economically speaking, will be forever (Bouwman).
Photo 4: A representation of nitrogen energy used across the world, showing how concentrated it is and how spreading it out would be feasible and better for the emissions.
Through examining just a few researcher’s theories on how to improve the agricultural system, clearly there are numerous different tactics that have been suggested that each individual thinks can solve the problems presented. High energy consumption and negative environmental effects are not petty issues, and surely solutions will continue to be brought up and tweaked. Though not clear which road agriculture will take in the coming years, one author, Allouche, makes a point to remind people that subsistence is a holistic process, not solely focused on the scientific processes involved. Allouche explains that wars, power and gender relations, trade policies, and climate change are all a part of the the evolving system, and cannot be ignored in understanding the problems and crafting the solutions. In Nature, one writer even proposes that the resolution lies in synthesizing photosynthesis, something not discovered yet, but will come in the future. There is no evident, all-encompassing solution yet, but taking steps like using alternative energy sources and focusing on strategic land usage get the agricultural system on the right track to solve the issues like energy usage and environmental effects.
Works Cited
Allouche, J. (2011, January). The sustainability and resilience of global water and food systems: Political analysis of the interplay between security, resource scarcity, political systems and global trade . Science Direct. Retrieved September 18, 2013, from http://www.sciencedirect.com/science/article/pii/S0306919210001272
Bouwman, A. F., van Grinsven, J. J., & Eickhout, B. (2010, January). Consequences of the cultivation of energy crops for the global nitrogen cycle. JSTOR. Retrieved September 18, 2013, from http://www.jstor.org/stable/27797791
Peccia, J., Haznedaroglu, B., Gutierrez, J., & Zimmerman, J. (2013, March). Nitrogen supply is an important driver of sustainable microalgae biofuel production. Science Direct. Retrieved September 18, 2013, from http://www.sciencedirect.com/science/article/pii/S016777991300022X
Woods, J., Williams, A., Hughes, J., Black, M., & Murphy, R. (2010, August 16). Energy and the food system . Philosophical Transactions of the Royal Society B: Biological Sciences . Retrieved September 18, 2013, from http://rstb.royalsocietypublishing.org/content/365/1554/2991.short
Clark, Jim. "The Haber Process for the manufacture of ammonia." Chemguide. N.p., 1 Apr. 2013. Web. 30 Sept. 2013. <http://www.chemguide.co.uk/physical/equilibria/haber.html>.
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