Livestock in Food Security: the debate widens...

With all the talk about environmentalism, and when we are all too busy hugging trees, we do forget other things that are happening on the planet. 

Sustainable development is not just some buzz-phrase cooked up in the nineties to gives us 15 year olds in the naughties to learn about in geography... well there is some truth in that too.

It is easy to forget that livestock, farming, is a valuable source of income for some of the poorest families in the world. A new report by the UN FAO on the importance of livestock to food security is a great summary of what kind of role livestock plays in developing nations in particular:

"livestock make a vital contribution as generators of cash flow and economic buffers, provided that market chains are organised to provide openings for small scale producers and traders and those in remote areas." (Forward, ix, FAO 2011: Livestock in Food Security)

The fundamental point is that livestock is not just a source of emissions, pollution, ethical controversy but at the end of the day is a source of food and income. Highlighting Sub-Saharan Africa, the expansion of agriculture (like that seen in China and India in the late 20th Century, Green Revolution) is pegged as a lifeline to reduce poverty and improve on the health problems.

The report highlights the changes in livestock production numbers and per capita consumption (Table 4) and also shows specific region and national scale changes and predictions (figures 1, 2 and table 16). I could bore you describing what they say... alternatively you could read? read isn't a good word to use, you don't 'read' a graph do you? observe the graphs yourselves.

As you can see, the numbers only increase...

Pastoralists number 120 million, and they depend on their livestock for food, income, transport and fuel; would it be fair to force them to stop stocking animals because climate change is getting out of hand? After all it is the 'developed' who have truly mechanised GHG emissions; should we tarnish everyone with the same brush? I don't think so.

This coupled with the need to maximise profits and reduce cost to open the market to everyone, livestock intensification is needed, and these agricultural systems are the worst environmentally, ethically and for small business competition which just does not have the finance to compete.

The report (FAO, 2011) goes onto stress that the dichotomy for environmental mitigation and sustainable economic development doesn't necessarily result in changes in the way development is going but rather the point that:

"suggest that the average global consumption of meat should be approximately 90 g a day, compared with the current 100 g, and that not more than 50 g should come from red meat from ruminants. If this target were achieved, it would lower the peak demand for meat. However, government-sponsored nutritional and healthy eating programmes have had limited success in changing dietary preference." (page 82)

The root of all evil it seems is not money but consumption, and a lot of it at that!

Inequality in food distribution is widely known. Last year I had the opportunity to sit in on a UN Young Ambassador Society events held at the Institute of Education and none other than the Executive Director of the World Food Programme gave a keynote speech. There, Josette Sheeran spoke quite bluntly about the inequality of food distribution worldwide. There is enough food but a billion remain undernourished and a billion over. That means there is still a lot of waste, and through waste reduction we can 'offset' carbon emissions and save the environment!

It is a very long read and I would bet there are gems that I haven't mentioned that I haven't read in the report... it's 100 pages long! What do you expect me to do???

Keep watching the posts!!

Meat the truth! Documentary Time!

This documentary, presented by a Dutch MP (Dutch Party for the Animals - might be a little biased) explores the role livestock plays in GHG emissions; pretty much what this blog is designed for!

The whole documentary is a great watch, please do!

To eat or not to eat meat… That is the question! Part 1: is it all demand?

When people debate the issue around livestock and the negatives of increasing production of meat and livestock associated products many say we should reduce meat consumption.

REALLY?!?

Now sure, one way we COULD reduce emissions from livestock is to cut down on our sausages, chicken legs and kebabs; after all, less cows and sheep farting, less direct methane emissions. But there are other issues around more animals on the planet that feed our hunger for meat. This paper by McApline et al. 2009 looks at environmental degradation in Colombia, Brazil and Australia due to expanding beef production and the deforestation it causes.

A big issue around emissions from livestock is the fact that there are large indirect GHG emissions from forest clearance and land use changes. The paper looks at factors that have increased beef production and surprisingly, in some countries like Brazil, it is not supply and demand which dictate beef production and emissions; its land prices. Land policy in Brazil has made it more profitable to clear once natural rainforest and keep it clear than let it be. The cheapest way to keep vegetation from establishing again is to regularly cut regrowth… cows are surprisingly good at turning grass into milk, meat, leather and other useful products for human consumption. This not only has a dramatic effect on local ecosystem services and physiography; the global consequences include depletion of the capacity for natural carbon sequestration.

Meat is big business. Curtailing meat production will directly affect the economies which rely mainly on agriculture and the primary sector. This is a controversial topic as if a country is able to utilise its natural resources within its territory for economic means and development ‘at the expense’ of the environment, who are we to judge? We chopped down our ‘oak’ forests centuries ago to fight wars with continental Europe. With the specific driver of meat production in this context being land management, economical profitability and natural lawn mowers; there is an assumption that if the main driver of livestock (beef) expansion being the one stated, then whether you eat the meat or not, there still will be emissions from it, albeit highly inefficient per capita of digestion. In the case of Australia, land management reform in the favour of protecting old growth forests has reduced the profitability in expanding cheap, subsidised (through tax incentives) cattle ranches. This protection has worked, again regardless of whether Sheila or Russell eat steak or love veggie burgers.

However, with all business, it is fundamentally based on a market; therefore demand. If demand for meat (whatever the reason) decreases; then production and emissions would – economically speaking – decrease too.

I will explore more arguments around decreasing dependence on livestock as a food source. However, I am guessing it isn’t as straight forward as I think it’s going to be!

Fossilised farts (and other agroGHGs)! Part 2: The expansion of Livestock and the debate around the Anthropocene.

Now, studies by Brook et al. (1996); Schlit et al. (2010); Sowers (2010); Burns (2011); Singrayer et al. (2011) and Wolff (2011) all show ice core records and other proxies (analogues for past environmental records) like speleothem (calcite deposits) to show CH₄ and other GHGs like N₂O over the Holocene (11 ka BP; Sowers, 2010) to 140 ka (Schlit et al. 2010). These records show the link between precessional cycles and CH₄ concentrations; but up until 5 ka, the CH₄ concentration deviated from what is expected due to the precessional cycle. The NH has been at an insolation minima due to the precessional cycle being in a NH negative stage (i.e. the southern hemisphere, SH, has more intense summers and winters).

This discrepancy between expected and observed therefore does not follow the natural process. Now shoot me if you must, but I agree with research put forward by Ruddiman, and I am joining in the argument/debate on the Anthropocene. In an article by Ruddiman et al. in a special issue Holocene published in June 2011 (where some of the other 2011 articles from Holocene are taken) attempts to falsify anthropogenic and natural increases in CO₂ and CH₄. The case states that only one other (stage 11) deglaciation has a similar increase in methane after the initial peak and decreasing tail (which would be due to a natural or at least non-anthropogenic process). All of the records (except stage 11) show a decrease of CH₄ in line with NH summer insolation minima. Stage 1 (our current Holocene/Anthropocene) does not follow this trend. Due to the rise and spread of humans through the globe, the establishment of civilisations and the first age of modernity through agricultural development, Ruddiman et al. (2011) and Fuller et al. (2011) show that it is expansion of agricultural practices of wet-rice farming and livestock intensification which is responsible for the anomalous rise in atmospheric methane contribution. This is significant for this blog as it shows (even among scientists like myself… ok I am only a student) humans have had an effect on the greater environment and the Earth’s ecosystems through a variety of anthropogenic process; relating this to livestock they include deforestation (increasing CO₂) and increased agricultural production (increasing CH₄ and later with the green revolution N₂O). This rise is evident 5 ka; that is why I believe that humans have had a significant impact on the earth before 250 yrs BP, it’s been 5 ka that’s how far the Anthropocene extends. This is shown in the graph taken from Fuller et al. 2011. 

Graph showing CH₄ predicted (NH insolation records) and measured CH₄ in GRIP ice core over time.

The Fuller et al. (2011) article looks at agricultural (pastoral and arable) contributions to prehistoric methane levels, using archaeological evidence to match it to the GHG records. This graph from their article shows the deviation from the predicted methane concentrations from the GRIP ice core. The black square points represent actual methane concentrations. The difference between the two data sets is ‘potentially’ cow farts and other anthropogenic processes (causing the deviation). They go deeper, investigating the spatial distribution of the technologies and knowledge of the more intensive (and greater GHG producing) agricultural techniques over time. Here are some maps showing the expansion of livestock practices:

Southern and Eastern Asia Livestock technique dispersal Fuller et al. 2011

Africa Livestock technique dispersal Fuller et al. 2011 

Southern Asia Livestock technique dispersal Fuller et al. 2011

The increased expansion of these farming practices means that more food was able to be cultivated, for direct food (like rice) or indirect food (like livestock feed).  This archaeological evidence shows the actual distribution of the increasing anthropogenic CH₄ sources. Another integral point (that will be elaborated on in part 3 of Fossilised farts) is the fact that the inter-polar gradient (IPG) between ice core records of CH­₄ concentration in Greenland and Antarctica begin to equate (Chappellaz et al., 1997; Burns, 2011). If for instance the NH boreal arctic polar circumference began to emit greater amounts of CH₄, then Greenland’s ice cores will have a greater concentration of the gas than Antarctica’s cores due to the proximity and difficulty of inter-polar diffusion. The fact that the IPG is levelling out shows that the source is low latitude; agricultural expansion into Africa, Southern Asia and South-Eastern Asia can be an explanation to this. Coupled with greater CH₄ emissions from the amazion basin (due to a stronger SH summer) and other low latitude CH₄ sources; this could explain the 5 ka rise. 

Fossilised farts (and other agroGHGs)! Part 1: The natural sources of methane in the past.

Records of trapped gas (of which some are fossilised farts) come from ice cores. GISP2 and GRIP (central Greenland) and the Vostok cores (Antarctica) show GHG levels fluctuating for millennia; stadials and interstadials (Brook et al., 1996). Focusing on methane and nitrous oxide (nitrous oxide will become increasingly significant during the green revolution and greater use of fertilisers), the role which livestock domestication and increased production has played on levels of those gases has been increasing over the late Holocene, correlating with the increasing human population and complementarily food demand.

Butt (pardon the pun), there are a variety of natural and other anthropogenic process which produce CH­₄ (and N₂O). To add to the debate about when humans had a global effect on the planet, we must be able to distinguish the gases between the various human and natural process, and that’s  where the magic happens…err, the science I mean.

The earth has always been able to regulate the gases in the atmosphere thanks to dynamic equilibrium. A long time ago, in a land quite close to home, early Homo sapiens sapiens lived as hunter gatherers and there was no such thing as an economic crisis. Over the last 140 ka (Schlit et al., 2010), atmospheric concentrations of greenhouse gases has varied naturally (as they have done before human mastery of emitting vast amounts of GHGs) due to feedback processes which are triggered by either external (orbital cycles, volcanic eruptions) or internal (organisms, Dansgaard-Oeschger cycles, Heinrich events, oceans) processes (Brook et al. 1996).

In the prior blogs I (hope to) have shown the main anthropogenic sources of the GHGs methane and nitrous oxide (as well as CO­₂, but due to its greater abundance in the atmosphere and number of sources is hard to quantify what proportion is due to livestock processes). These two gases in particular are good indicators of livestock production and other agricultural process as they can have a signal specific to the process of formation and as natural methane is dependent on the precessional cycle of the earth (explained further in part 2) it is relatively easy to predict and categorise as it increases and decreases in line with the earth’s precession. The main sources of methane come from the humble bacteria. Decomposers, who (as the name suggests) decompose organic matter (dead plants, leaves, bodies…err cow poo or rice stalks, to name but a few) anaerobically (without oxygen) which produces methane.

The best way of removing oxygen from soil (where tonnes of organic matter meet with anaerobic decomposers) is through water-logging/increasing the water table. Like any other organic process involving enzymes; the warmer the environment, the greater the rate of the process occurs, ergo more methane.

More organic matter + higher temperatures + greater water logged soils + decomposer bacteria = a load of natural methane!

The greatest sources of natural methane are large areas on earth (where else?) where temperatures are sufficient to allow decomposition to occur, have large stores of organic carbon in the soil and are highly water-logged. The source of the organic material is the crux of the matter, if it comes from cows stomachs via the rectum (LOL) then increasing the cow population directly increases methane produced from anaerobic decomposition, as well as their farts of course.

Tropical/sub-tropical and boreal (peat land) wetlands are the largest sources of natural methane. Other natural sources include termites, wild fires, wild animals farting, methane hydrate release and oceans (Ruddiman et al., 2011). In the ice core records, the direct correlation between the CH₄ concentration and precessional cycle boils down to the northern hemisphere summer insolation. The precessional cycle dictates the amount of summer temperatures in each hemisphere, governing the seasonal intensity (temperatures/precipitation) and the monsoons. As the direction of the tilt of the earth towards the sun changes cyclically over 22-26 ka (Ruddiman et al., 2011), when the northern hemisphere (NH) is pointed towards the sun when at the same time the earth is closest (the perihelion) to the sun then the NH summer insolation is high, increasing temperatures and precipitation, as seen in speleothem records across the tropics (Burns, 2011). Due to the inter tropical convergence zone (ITCZ) shifting northwards, NH precipitation increases the water logged state of the tropical/sub-tropical rainforests and greater insolation heats and melts permafrost in the boreal band across North America and Eurasia; paving the way for those nasty bacteria to unlock the frozen carbon in the form of the by-product that is CH₄.

You see… all those old-fashioned climate sceptic and climate change deniers are right… it’s not the fault of humans; we just have to destroy all those evil decomposer-bacteria that produce this bad gas, get the Dettol at the ready!

So what is the problem with excessive farting (also burping, urinating and excreting)?

Why is it even an issue worth discussing in a blog dedicated to the world of excrement? Well the fundamental problem we face, not just as a species, but as inhabitants of earth, is climate change. We humans use the planet as our only home, kitchen, garden and toilet. Like any other confined space, when you begin to change the chemical make-up of the gas enclosed in that volume, you begin to change the overall physical, chemical and thermal properties of that gas. In the case of excrement, methane (CH₄) and nitrous oxide (N₂O) is produced through a variety of processes (as is carbon dioxide, CO₂) which contribute to the greenhouse effect (Popp et al., 2010). Carbon dioxide is the most significant anthropogenic produced GHG due to the sheer quantity that is emitted into the atmosphere from human activities.  

However, as I touched upon in the previous post, over 100 years, the same amounts CO₂, CH₄, and N₂O have varying potencies due to their thermodynamic properties. This property is applied as a ration of heat trapped by one unit mass of the GHG compared to one unit mass of CO₂; this is called the Global Warming Potential (GWP) (Pitesky et al., 2009). As it a ratio, CO₂ has a GWP of 1; CH₄ has a GWP of 23 (in the previous post I wrote that the potency of methane was 20 times that of carbon, it was wrong sorry!); N₂O is 296 (FAO, 2006). From this data, it shows how important methane and nitrous oxide produced from livestock production, and in particular from poo, will be an increasing problem, not just as the total number of GHGs (CO₂ and non-CO₂) is set to increase from projected and modelled figures (Popp et al., 2010). In addition, with populations estimated to reach 9 billion by 2055 (World Bank, 2011) and increasing qualities of life reflecting greater demand for meat in the diet; livestock rearing is set to increase; that equates to a whole load of shhhhh… excrement.

The United Nations Food and Agriculture Organisation (FAO) commissioned a report on the impact livestock production has on the planet,Livestock’s long shadow (FAO, 2006). As a whole, livestock (either directly or indirectly) is responsible for 18% of total anthropogenic GHG emissions (FAO, 2006); those figures broken down into individual GHG include:

·  Carbon dioxide (CO₂) 9% of global anthropogenic emissions.

·  Methane (CH₄₎ 35 – 40% of global anthropogenic emissions.

·  Nitrous oxide (N₂O) 65% of global anthropogenic emissions.

·  Ammonia (NH₃) 64% of global anthropogenic emissions.

However, as I will investigate later on in the blog (or further towards the top of the blog), Excretion and everything  does not just play an integral role to GHG emissions, it also plays a vital role in the nutrient cycle, particularly phosphorous and nitrogen. Phosphorous (P), as well as nitrogen (N) in the form of nitrates and other vital macronutrients like magnesium (Mg), potassium (K) and calcium (Ca) are required as well as a variety of other micro nutrients (Robinson, 2004). Phosphorous is often a limiting factor in plant production, due to its vital role as an ingredient in deoxyribonucleic acid (DNA) and ribonucleic acid (RNA), the building blocks of life; and in the Adenine triphosphate (ATP) which is the primary method of intracellular energy release and storage (Biology-Online, 2011), so we can all move, keep warm and most importantly… LIVE! Also, specifically to plants, P is necessary for healthy root growth, vital for the uptake of water and the other nutrients. The role fertiliser plays is significant, and indeed focusing on one of the nutrients, phosphorous, an increasingly important point has surfaced. Livestock (cows for example) need to eat; feed is created from plants; high amounts of land and biomass is required to produce vast amounts of feed; limited land resources dictates more intensive farming methods; greater dependence on higher yields; synthetic fertilisers created to provide the vital nutrients for plant growth; mining of phosphates from a finite source requires large amounts of energy whilst depleting the source.

As you can see, just from scratching the surface, cow (and other animals’) farts and poo pose a more serious problem than the humorous connotations applied to them suggest. Over the next few weeks and posts I hope to show you a greater insight in to the world of climate change, nutrients (re)cycling, pollution, eutrophication, renewable energy and many, many more uses, and subjects, which poo influences.

This blog may overlap with others, in fact it will. A post by fellow GEOG3057 blogger Emma (I hope she is Ok with me using her name), touches on the renewable potential of methane gas from… well cow farts. Another blog dedicated to the debate around biofuels can also shed light on the increasing diversification of energy sources, by another fellow GEOG3057 blogger Yulia. But those topics are for another time!

Next I hope to give you an insight into past methane releases and the relationships between the potent GHG and the atmosphere, looking at palaeo records of methane…essentially fossilised cow farts… Ok well some of the methane was produced by pre-modern time cows farting. Until then… watch those deadly emissions!

References:

Biology Online, 2011, ATP Definition. Available from: http://www.biology-online.org/dictionary/Atp. [Online] accessed 24/10/2011.

FAO, UnitedNations, Food and Agriculture Organisation, 2006, Livestock’s Long Shadow: Environmental issues and options, FAO-UN:Rome.

Pitesky, M. E., Stackhouse, K. R. and Mitloehner, F. M. 2009, Clearing the Air: Livestock’s contribution to climate change, Advances in Agronomy, 103, 1-40 pp.

Popp, A., Lotze-Campen, H., Bodirsky, B., 2010, Food consumption, diet shifts and associated non-CO₂ greenhouse gases from agricultural production. Global Environmental Change, 20, 451-462 pp.

Robinson, G. 2004, Geographies of Agriculture: Globalisation, restructuring and sustainability. Harlow: Pearson Publications Limited.

World Bank, Development Research Group, Human Developmentand Public Services Team, (Das Gupta, M., Bongaarts, J. and Cleland, J.) 2011, Population, Poverty and SustainableDevelopment: A Review of the Evidence, World Bank: Washington D.C., WPS5719.

If you find this sh.... stuff interesting then you might find these blogs interesting to! 

Please check them out, as I try to myself!

Agriculture: Human Health and Earth Health: http://robs-agriculture.blogspot.com/ 

Biofuels: Way Ahead or Blind Alley: http://biofuels-wayaheadorblindalley.blogspot.com/

Fixing Climate Change: http://fixingclimatechange.blogspot.com/

Welcome!

Welcome!

This blog is to inform, amaze, inspire and of course explain the many uses of poo… Now please do not adjust your screens or refresh the page, I did just write poo.

Before we indulge ourselves in the wonders of excretion, understanding of the past is vital to analysing potential solutions of present problems for the future. In this context, methane (CH4) is a significant greenhouse gas (GHG), 20 times more potent than carbon dioxide (CO2) and one way that it is emitted is in the form of cow (and other animal) farts, and the anaerobic decomposition of organic materials, like manure. 

But before all of that! Here is a video that makes light of the fundamental argument that I am making.

Enjoy and I will post again soon!