Limit Agriculture’s Contribution to Climate Change
by Brianna King

 

Climate change is a global issue, driven by many sectors including energy, transportation, agriculture, etc. Many people are familiar with common efforts to reduce emissions, whether mileage restriction for cars, electric cars, more efficient appliances, or solar and wind power technologies. These policies or publicly driven efforts to reduce emissions often surround the energy and transportation sectors, yet according to the EPA, the agriculture sector contributed to 9% of emissions in 2014.[1] Additionally, in 2006 the Food and Agriculture Organization of the United Nations found that livestock and agriculture contribute to 18% of greenhouse gas emissions in the world.[2] However, the World Watch Institute found that the agriculture sector is emitting 51% of green hours emissions.[3] While these numbers vary, they point towards the fact that agriculture is largely contributing to the climate change issue and people need to pay attention to this sector’s greenhouse gas emissions. Overall, policies should be implemented to encourage farmers to take actions to reduce their greenhouse emissions.

 

New policies and technologies need to address these emissions, which are largely methane and nitrous oxide.[4] Methane emissions typically come from enteric fermentation, which is the digestive belching of livestock. Nitrous oxide is emitted through soil management, such as applying fertilizers to fields. New technologies would therefore address one of these two issues.

 

A new prospective technology to limit methane emissions is being implemented by a hog farmer, named Tom Bulter, in North Carolina. His farm deposits the hog waste in a lagoon, or lake-like area in the ground.[5] These pools collect waste and methane is released from this waste directly into the air. Tom decided to invest in tarps which cover his pools and collect the methane. This methane can then be pumped out of the lagoons and burned or pumped to an alternative location, such as an electricity plant. In the long term, hopefully enough farmers will invest in this technology, such that large amounts of methane can be pumped throughout the state to an electric plant. This electric plant could then use methane, rather than steam or natural gas, to drive the turbines to generate electricity. This would therefore, limit methane emissions and utilize the methane in a way to create energy.

 

This same idea can be utilized by methane digesters. These digesters hold manure in a tank, heated to a set temperature, such as roughly 100 degrees Fahrenheit. The heat allows the methane to escape, which the tank collects and burns, like natural gas.[6] The rest of the manure is now free of methane and can be used as before, such as on crop fields. Through burning the captured methane, the digester can create electricity, to either use on the farm or sell back to the utilities companies.[7] This method can be applied to a variety of livestock, which enables a large portion of livestock’s emissions to be reduced.

 

Aside from capturing the emissions emitted by livestock, there are also methods of reducing the amount an animal emits. Current studies have tested altering ingredients in animals feed to reduce their enteric fermentation. A study on dairy cattle added nitrate to the daily diet of dairy cows, which ultimately limited the methane these cows emitted, compared to a control group, by 16%. Importantly, there was were no changes in animal behavior and milk content was only altered in protein levels from 3.21% to 3.05±0.058%, which was considered negligible.[8] This finding gives hope for slightly altering feed in animals to reduce each animals contribution to emissions, without having an adverse effects of the animals food production or animal’s livelihood.

 

Overall, agriculture is contributing to a significant portion of our greenhouse gas emissions and this sector must not be ignored in order to address climate change issues. While we are not as familiar with efforts to reduce these emission, new technologies and studies are being undertaken to reduce these emissions. While a few farmers or companies have started to invest in these new technologies, these ideas need to be implemented amongst many farmers and as studies’ findings are proven effective, they must be implemented.

 
Phillip comment:
The emission reduction innovations presented in your blog post are very interesting. Before reading this post, I didn’t know that livestock animals emit such a large amount of greenhouse gases through enteric fermentation. Methane emission has taken a back seat to CO2 emission from both a regulatory and a public knowledge point-of-view. I think the capture and reuse of methane in the production of electricity offers an ingenious way of reducing methane emissions. Additionally, I think methane-reducing practices in agriculture could quickly spread throughout the industry if methane digesters and waste-lagoon tarps prove to be cost effective.
 
ZaKerra comment:
I appreciate that the focus of your recommendation is on the farmers and actions they can take to mitigate climate change through agriculture. The combination of technological innovations and farmer action can go a long way in changing the emissions and harmful byproducts of our agricultural system. I think the only issue in farmers changing some of their practices is the financial burden it may have on some of the smaller farms. I think that, as you say in your conclusion, there are also studies yet to be conducted to find more ways of reducing emissions. There may be research needed to alleviate some of the costs as well. Especially with the new technologies. Overall, this is a great topic, and I think it is important to start from this level for the issue of farm emissions. Sweeping policy and legislation may not work as well for agriculture.
 
 

 

Citations
[1] “Sources of Greenhouse Gas Emissions.” EPA. Environmental Protection Agency, 14 Feb. 2017. Web. 15 Mar. 2017.

[2] Steinfeld, Henning. Livestock’s Long Shadow: Environmental Issues and Options. Rome: Food and Agriculture Organization of the United Nations, 2006. Print.

[3] Goodland, Robert. “Lifting Livestock’s Long Shadow.” Nature Climate Change 3.1 (2012): 2. Web.

[4] United States. EPA. Inventory of U.S. Greenhouse Gas Emissions and Sinks: 1990 – 2014. N.p., 15 Apr. 2016. Web.

[5] “Www.wholehognc.org.” Www.wholehognc.org. N.p., n.d. Web. 15 Mar. 2017.

[6] “Farm Power.” Farm Power. N.p., n.d. Web. 15 Mar. 2017.

[7] Ibid.

[8] Zijderveld, S.m. Van, W.j.j. Gerrits, J. Dijkstra, J.r. Newbold, R.b.a. Hulshof, and H.b. Perdok. “Persistency of Methane Mitigation by Dietary Nitrate Supplementation in Dairy Cows.” Journal of Dairy Science 94.8 (2011): 4028-038.

 

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