Rucksacks on cows? Surely not...

Yes the title is correct - okay, maybe not an actual rucksack, but an idea I came across that is being proposed by Argentina's INTA governmental research body is to secure inflatable bags to cows backs in order to reduce methane (CH₄) consumption. The way this is proposed to work is to connect a tube from the cow's rumen (where the CH₄ gets emitted from) to an inflatable bag so that the gases are stored, rather than escaping into the atmosphere. These gases are then transferred into containers which have the potential to be used as an energy source. Very bizarre concept I know, but if it is a solution, could this mean we can have a burger guilt-free?

(source: ecouterre.com)

The Climatarian Challenge results!

As you may remember a few posts back, I decided to begin 'The Climatarian Challenge' through tracking what I had been eating and inputting it into an app to see how much carbon I was 'consuming'. Today was the end of my challenge - sadly I only just failed the challenge by ending on 8002 points (equivalent to 80.02kg of carbon) rather than the 8000 points that was the goal. However I cannot be too disappointed though as I only 'ate' 20g of carbon more than the goal! Using the app has been so interesting and I felt so motivated throughout to seriously consider what I was consuming. The only criticism I would have off the app was that when inputting whether you had eaten a certain type of meat or not, you then had to choose which portion size it was equivalent to out of a choice of three. Unfortunately there was no actual guidelines into what each portion size was equivalent to so a lot of it was guess work, which could have meant I was either under- or over-estimating how much carbon I was consuming. Nevertheless definitely give this a go and I guarantee it will make you think twice about what you are eating - give the video a watch so you know what's in stall!

Dairy products and their impacts

Recently I have been hearing so much about 'Veganuary' - the idea to attempt to become a vegan for the whole of January. I mean, for me, this is not particularly appealing as I think I would probably fail on the first day. However it has given me the inspiration to research into the impacts of the dairy industry on climate change and whether it is beneficial to reduce or even completely avoid dairy products. Additionally this is one of the areas associated with cattle that I have not explored. To my surprise, statistics reported in The Guardian (2014) stated that beef and dairy make up approximately 65% of all livestock emissions; whats more is that dairy consumption is projected to rise globally by 65% by 2050.  In this post I have examined two different studies, both of which are investigating the environmental benefits of reductions of dairy among other greenhouse gas (GHG) polluting products.

1. Westhoeck et al. (2014)

The authors within this study aimed to find out what the effects of replacing meat, dairy and eggs with plant-based food would be on both the environment and human health; here I have just focused on the consequences on the environment. The study explored six alternative diets (however only five were actually presented in the main body of the study) which are shown in this table:

Figure 1 | Table of the five alternative diets.

(After Westhoeck et al., 2014)

The main findings of this study were that the alternative diets where a 50% reduction was observed lead to great reductions in GHG emissions and reactive nitrogen, 25-40% and approximately 40% respectively. This certainly highlights the benefits from reducing meat, dairy and eggs. Although one point I would make was that it is difficult to observe the individual contribution of reducing dairy consumption on these emissions as they are grouped together. Nevertheless it is clear dairy products are prominent contributors to climatic changes. One point that the study does bring to our attention is the questioning over whether these dramatic behavioural changes are actually realistic. Even I can admit that giving up all meat and dairy products is too challenging for me and many other people I have spoken to would not be able to do so. 

2. Steer (2015)

Alternatively to the previous study, Steer (2015) examines solely the impacts of dairy products on the environment which certainly makes exploring its individual contribution to climatic change easier. This study specifically examines whether switching from conventional dairy systems to an alternative production of dairy that uses 'non-bovine pathways' (YDM). This alternative involves producing milk proteins by the combination of yeast and vegetable oil, rather than dairy cows. The study found that this alternative had a significant reduction in many environmental impact categories, shown in this table:

Figure 2 | Modelled land, water and energy requirements, plus GWP, of producing 1 L YDM compared to data for conventional dairy productions. 

(After Steer, 2015)

As shown, the efficiency savings of using this alternative are great. However the ranges for some categories, particularly energy, are very large which suggests some uncertainties in the results. Another criticism of the study is when compiling the values for YDM, for the four categories, for sunflower oil, sucrose, transport and YDM synthesis, numerous studies were utilised to assemble these values. This inconsistency could raise questions about the validity of the concluding remarks.

Perhaps this is the new way forward - rather than changing behaviour, change the product? However it is seriously important to consider whether anyone would actually buy this product. But, it could be argued that there has been a great increase in the purchasing of milk alternatives, for example soy and coconut milk, as projections reported in The Guardian (2016) stated that the milk alternative industry is expected to be worth more than $10bn by 2019. Therefore investing in YDM could be a plausible solution - please comment below your thoughts!

Climate One podcast

Today on my commute into university, I listened to a podcast by 'Climate One at The Commonwealth Club' which discussed the relationship between climate change and various foods. It was entitled 'C1 Revue: Climate Change on your Kitchen Table' and lead by Greg Dalton, the founder of Climate One. Within the podcast, there were two parts that I found particular interesting and relevant to this blog.

16 minutes into the podcast...

Greg Dalton and others were discussing the notion of veganism and dairy products, and their influences on climatic change. What was most fascinating to me was the notion that rather than global population driving the demand for food, it is in fact wealth. Countries like India and China, and regions such as south-east Asia are gradually developing into middle class areas and following similar consumption patterns to western countries by eating more expensive foods. Other studies have noted this trend also, stating that there has been an increase in high meat diets and that ruminant meat consumption is becoming a symbol of growing affluence in countries (McAlpine et al., 2008; Lambin and Meyfroid, 2011).

27 minutes into the podcast...

Joining Greg Dalton in this part of the podcast was Kip Anderson, producer of Cowspiracy, Jonathan Kaplan, director of the food and agriculture program at NRDC, and Nicolette Hahn Niman, author of the book 'Defending Beef'. Various aspects of Cowspiracy were discussed and critiqued, which I found engaging as I have watched the documentary and have written a blog post about it. Kaplan mentioned that there was no evidence to support the allegation in Cowspiracy which was that environmentalist groups have been taking money from the livestock industry to cover up agricultural emissions. In addition, Hahn Niman disagreed with a notion in the documentary which was that livestock is inherently problematic. She discusses that if livestock agriculture is conducted well, it can have a positive environmental impact because livestock plays a role in aspects of soil, such as its fertility and microbiology. 

I found that the overall message from the podcast was that sustainable food production and consumption is necessary to reduce our environmental impact. Additionally, this does not have to be done through a zero-meat diet or drastic changes to one's lifestyle. Instead small steps, for example cutting down on meat or cheese consumption, can have a positive environmental impact; the phrase 'eat less, enjoy more' that was stated during the podcast definitely promotes this attitude. I highly recommend giving this a listen - click the photo below to get going!

(source: stitcher.com)

Are dietary changes the only way forward?

A few days ago I read on the news that since the introduction of the 5p carrier bag charge, there has been an approximately 50% reduction in the number of plastic bags found on beaches in the UK. Could it therefore be argued that reducing our beef consumption in the UK could be tackled through taxing the meat? 

An article from The Guardian explored this idea, reporting findings from a study by Springman et al. (2016). The authors used an agriculture-economic model 'IMPACT' to project future global consumption of various agricultural commodities by 2020 in order to analyse whether taxing these commodities, based on their greenhouse gas (GHG) emissions, could affect both GHG emissions and human health. Figure 1 illustrates the outcome of the introduction of the GHG tax, which demonstrates the dramatic reduction in GHG emissions after the tax is implemented, particularly the decrease in world GHG emissions produced from beef. Overall the study found that the introduction of tax on foods would result in a reduction of food-related GHG emissions of approximately 9% by 2020. 

Figure 1 | a. Price and GHG taxes for various commodities in US dollars per kg; b. Percentage changes in the price and consumption of each commodity with the introduction of GHG taxes; c. The changes in GHG emissions of each commodity after the introduction of the GHG tax in various parts of the world - high-income countries (HIC); low and middle income countries in Africa (AFR); America (AMR); Eastern Mediterranean (EMR); South-East Asia (SEA); and the Western Pacific (WPR).
Commodity price and GHG tax varied by commodity and region because of different GHG emissions produced by each commodity and varying management practices in the different regions, respectively.

(After Springman et al., 2016)

However, the authors stated a key limitation in the calculation of the GHG emission reduction. This was that the model did not consider all climate-carbon feedbacks, in particular for methane, which is applicable for methane-intensive foods, like beef. Another issue that could arise from the introduction of tax on GHG-intensive foods in the UK is the financial impact it could have on lower-income communities. 

The Committee on Climate Change (2008) came up with a new approach in identifying ways to reduce the GHG emissions produced by livestock agriculture (Gill et al., 2010). These were:

1) Lifestyle changes
2) Agricultural changes

3) Technological changes 

Decreasing GHG emissions through lifestyle changes has been thoroughly discussed in previous posts, i.e. dietary changes, therefore the remainder of this post will explore these other two approaches.


Agricultural changes

A previous blog post discussed how changes in the management of land use in Brazil could affect GHG emissions. As well as this proposition, changes in cattle feed is commonly considered. The 2013 State of Food and Agriculture report published by the Food and Agricultural Organisation of the United Nations (FAO) stated that one of the main sources of GHG emissions is from feed production and processing (The Guardian, 2013). The composition of feed can directly influence the volume of nitrogenous components excreted in the manure of cattle (Gill et al., 2010).

(source: synthite.com)

Miesselbrook et al. (2005) researched whether the amount of crude protein (CP) in a cattle’s diet affected the nitrogen produced by the cattle through examining the urine and faeces of cows which consume different diets. One finding was that reducing the CP content of a cattle’s diet from 19.4% to 13.6% resulted in reductions of both nitrogen excretion and urinary nitrogen excretion, 30% and 45% respectively, which indicates the possibility of dietary alterations to decrease GHG emissions. A second dietary change proposition I came across was on the ‘Science by Guff’ page on Instagram, which featured a post that stated how new research in Australia has discovered that introducing a type of dried seaweed, asparagopsis taxiformis, into cattle’s diet resulted in a dramatic decrease in methane (CH₄) emissions produced by the cattle.  Not only did they trial this on cattle but also sheep; incorporating this seaweed as 2% of the sheep’s diet led to a decrease in the production of CH₄ emissions by between 50% and 70% over a 72-day period. However, would there be a sufficient amount of seaweed to feed the global cattle and sheep population in order to reduce CH₄ emissions?

Technological changes
It could be argued that technological changes are advantageous because it implies that people would not have to change their lifestyle or diet, which is definitely favorable. According to Gill et al. (2010), a plethora of research is being done into the use and effect of nitrification inhibitors in New Zealand as this could assist in reducing GHG emissions. A study by Gillingham et al. (2015) performed a three year research programme across five sites in New Zealand to examine the effects of the nitrification inhibitor, ‘dicylandiamide’ (DCD), on soil mineral nitrogen (N) changes, nitrous oxide (N₂O) emissions and pasture dry matter production. Within New Zealand itself, N₂O emissions have increased by 23% between 1990 and 2009, largely as a result of a rise and intensification in N-fertiliser usage which is mainly attributed to dairy farms. The authors in the study found that there was an overall decrease in N₂O emissions between 2009 and 2012, accompanied by the delay of nitrification and reduction of nitrate accumulation in soils as a result of DCD application. These findings were corroborated by Ledgard et al. (2014), who carried out a similar investigation in New Zealand, where N₂O emissions also decreased over a three year period through the use of DCD. An additional advantage the study noted was that a decrease in N loss through emissions mean that more N remained in the soils which could result in greater plant growth.

However, both studies observe that the emissions of N₂O appear to be influenced by climatic changes, primarily temperature and precipitation, as this can affect the DCD residency time in soils. This creates a limitation in the use of this particular nitrification inhibitor as it suggests that success from DCD use may only occur in particular countries or regions with a certain climate. In addition, DCD is extremely expensive to use and so may be too costly for large-scale agricultural usage (Zerulla et al., 2001). 

What is the answer?

In my opinion, the root of the problem is that society is not fully aware of the impacts that cattle rearing has on the environment and how greatly it contributes to climate change; maybe if society was more informed through the government or environmental organisations, lifestyle changes would be more prevalent. However, as many people are reluctant to changing their behavior, perhaps these alternative options are the way forward.