Organic agriculture and climate change

29 07 2009

global6

The debate over sustainable agriculture has gone beyond the health and environmental benefits that it could bring in place of conventional industrial agriculture. For one thing, conventional industrial agriculture is heavily dependent on oil, which is running out; and it is getting increasingly unproductive as the soil is eroded and depleted. Climate change will force us to adopt sustainable, low input agriculture to ameliorate the worst consequences of conventional agriculture, and to genuinely feed the world.

And climate change is upon us.  I’m sitting in Seattle experiencing an “historic heat wave” while reading that the Hadley Center of the British Meteorological Organization has said the world’s temperature will increase by 8.8 degrees F rather than 5.8 degrees F this century.

The Inter-Governmental Panel on Climate Change (IPCC) has said we can expect a considerable increase in heat waves, storms, floods, and the spread of tropical diseases into temperate areas, impacting  the health of humans, livestock and crops. It also predicts a rise in sea levels up to 35 inches this century, which will affect something like 30% of the world’s agricultural lands (by seawater intrusion into the soils underlying croplands and by temporary as well as permanent flooding). If the Hadley Center is right, the implications will be even more horrifying: Melting of the Antarctic, the Arctic, and especially the Greenland ice-shields is occurring far more rapidly than was predicted by the IPCC. This will reduce the salinity of the oceans, which in turn  weakens (if not diverts) oceanic currents such as the Gulf Stream from their present course . And if that continues, it would eventually freeze up areas that at present have a temperate climate, such as Northern Europe.

According to the Institute of Science in Society, “It is becoming clear that climate change and its different manifestations (as mentioned above) will be the most important constraints on our ability to feed ourselves in the coming decades. We cannot afford to just sit and wait for things to get worse. Instead, we must do everything we can to transform our food production system to help combat global warming and, at the same time, to feed ourselves, in what will almost certainly be far less favorable conditions.”

But before we tackle the question of how best to feed ourselves during these “less favorable” times: how can organic agriculture help with global warming?

It’s generally assumed that various Greenhouse Gases (GHG) are responsible for
global warming and climate change.   On a global scale, according to a study commissioned by IFOAM, agriculture has been responsible for approximately 15% of all GHG emissions:

  • 25% of all CO2 emissions come from agriculture
  • 60% of CH4 (methane) emissions come from agriculture
  • 80% of N2O (nitrous oxide) emissions  come from agriculture

About 60% of the CO2 emissions from human and animal activities is absorbed by the oceans and plants; the remaining 40% builds up in our atmosphere.    So what to do about the 40% that’s building up in our atmosphere?  Where can it be stored?

428

In  looking at ways to “defuse” this CO2 build up, scientists began looking at carbon “sinks”.  Carbon sinks are natural systems that suck up and store carbon dioxide from the atmosphere. The main natural carbon sinks are plants, the ocean and soil. Plants grab carbon dioxide from the atmosphere to use in photosynthesis; some of this carbon is transferred to soil as plants die and decompose. The oceans are a major carbon storage system for carbon dioxide. Marine animals also take up the gas for photosynthesis, while some carbon dioxide simply dissolves in the seawater.

Initially forests were thought to be the most efficient way to sequester (or absorb) this carbon.  It was thought that escalating fossil fuel consumption could be balanced by vast forests breathing in all that CO2.   But  these sinks, critical in the effort to soak up some of our greenhouse gas emissions, may be maxing out, thanks to deforestation, and human-induced weather changes that are causing the oceanic carbon dioxide “sponge” to weaken.

New data is beginning to show that it may be that the soil itself makes more of a difference (in terms of carbon sequestration)  than what’s growing on it.  On a global scale, soils hold more than twice as much carbon as does vegetation (1.74 trillion tons for soil vs. 672 billion tons for vegetation) – and more than twice as much as is contained in our atmosphere.

The Rodale Institute Farming Systems Trial (FST), launched in 1981, is a 12 acre side by side experiment comparing three agricultural management systems: one conventional, one legume-based organic and one manure-based organic.  In 23 years of continuous recordkeeping,  the FST’s two organic systems have shown an increase in soil carbon of 15 – 23%, with virtually no increase in non-organic systems.

carbonsoil

This soil carbon data  shows  that improved global terrestrial stewardship–specifically including regenerative organic agricultural practices–can be the most effective currently available strategy for mitigating CO2 emissions. [2]

But although it is well established that organic farming methods sequester atmospheric carbon, researchers have yet to flesh out the precise mechanisms by which this takes place.   One of the keys seems to be in the handling of organic matter – while conventional agriculture typically depletes organic matter, organic farming builds it thru the use of composed animal manures and cover crops.  In the FST, soil carbon levels increased more in the manure-based organic system than in the legume-based organic system, presumably because of the incorporation of manures, but the study also showed that soil carbon depends on more than just total carbon additions to the system–cropping system diversity or carbon-to-nitrogen ratios of inputs may have an effect. “We believe that the differences in decay rates [of soil organic matter] have a lot to do with it,” says Hepperly, since “soluble nitrogen fertilizer accelerates decomposition” in the conventional system.

The people at Rodale put the carbon sequestration argument into an equivalency we can all understand: think of it in terms of the number of cars that would be taken off the road each year by farmers converting to organic production.  Organic farms sequester as much as 3,670 pounds of carbon per acre-foot each year. A typical passenger car, according to the EPA, emits 10,000 pounds of carbon dioxide a year (traveling an average of 12,500 miles per year). Here’s how many cars farms can take off the road by transitioning to organic:  car

U.S. agriculture as currently practiced emits a total of 1.5 trillion pounds of CO2 annually into the atmosphere. Converting all U.S. cropland to organic would not only wipe out agriculture’s massive emission problem, but by eliminating energy-costly chemical fertilizers, it would actually give us a net increase in soil carbon of 734 billion pounds.

Organic agriculture is an undervalued and underestimated climate change tool that could be one of the most powerful strategies in the fight against global warming, according to Paul Hepperly, Rodale Institute Research Manager.  In addition to emitting fewer GHGs while sequestering carbon, organic agriculture uses less energy for production.  A study done by Dr. David Pimentel of Cornell University found that organic farming systems used just 63% of the energy required by conventional farming systems, largely because of the massive amounts of energy requirements needed to synthesize nitrogen fertilizers.

Taking it one step further beyond the energy inputs we’re looking at, which help to mitigate climate change, organic farming:

  • eliminates the use of synthetic fertilizers, pesticides and genetically modified organisms (GMOs) which is  an improvement in human health and agrobiodiversity
  • conserves water (making the soil more friable so rainwater is absorbed better – lessening irrigation requirements and erosion)
  • ensures sustained biodiversity
  • and compared to forests, agricultural soils may be a more secure sink for atmospheric carbon, since they are not vulnerable to logging and wildfire.

Organic production has a strong social element and includes many Fair Trade and ethical production principles.  As such it can be seen as more than a set of agricultural practices, but also as a tool for social change.[3] For example, one of the original goals of the organic movement was to create specialty products for small farmers who could receive a premium for their products and thus be able to compete with large commercial farms.

And actually, it seems that modern industrial agriculture is on the way out.  The Food and Agriculture Organization of the United Nations (FAO) admitted in 1997 that wheat yields in both Mexico and the USA had shown no increase in 13 years  – blamed on the fact that fertilizers are becoming  less and less effective, as are pesticides.   The farmers are losing the battle.  Conventional agrochemical use (which includes many highly toxic substances) also has many immediate human impacts:  documented cases of short term illnesses, increased medical costs and the build up of pesticides in human and animal food chains.  The chemicals also contaminate the drinking and ground water.  And industrial agriculture is far too vulnerable to shortages in the availability of fuel and to increases in the price of oil.

That’s a lot to think about when looking for your next T shirt, so before you plunk down your money for another really cool shirt,  think about what you  will be getting in exchange.


[1] I should point out that although “sinks” in vegetation and soils  have a high
potential to mitigate increases of CO2 in the atmosphere, they are not
sufficient to compensate for heavy inputs from fossil fuel burning.  The long-term solution to global warming is simple:  reduce our use of fossil fuel, somehow, anyhow!
Yet the contribution from agriculture  could buy time during which
alternatives to fossil fuel can take affect – especially if that agricultural system is organic.

[2] http://www.rodaleinstitute.org/files/Rodale_Research_Paper-07_30_08.pdf

[3] Fletcher, Kate, Sustainable Fashion and Textiles, p. 19





Cotton is a good way to buy oil.

21 07 2009

Provocative title, isn’t it?  But I didn’t say it, the statement comes from Jim Rogers, one of the world’s most successful investors and co-founder of the Quantum Fund (with George Soros) from which he retired in 1980.  Since then he has been a college professor, world traveler, author, economic commentator and creator of the Rogers International Commodities Index.  And now, Jim Rogers says he’s investing in agriculture.

Jim Rogers is looking at cotton as a commodity (and an investment strategy), based on the fact that almost everything has some dependence on energy prices, based on  the embodied energy of the product.  He bases his decision on the fact that so many textiles today are made from synthetics – which come from oil.  Since the price of oil is going up (and will likely continue to go up) the price of synthetics is also going up.  So textile makers are reverting to natural fibers.  Cotton is the most popular natural fiber in the world, and the cotton – oil connection is both direct (through the use of synthetic fertilizers and pesticides), and indirect  (land formerly used to grow cotton can be shifted to other production to feed ethanol demand).  As Jim Rogers says,  “I hadn’t thought of this cotton-oil connection before, and it’s drawing these connections before others do that makes a great investor.”

If we are going to “reduce our dependence on foreign oil” (as the government likes to put it), shouldn’t we be looking at agriculture?  Dr. Albert Bartlett, Professor Emeritus in Nuclear Physics at Colorado University, Boulder, has said that the definition of “modern agriculture is the use of land to convert petroleum into food”.

I checked the web – and agriculture is really an energy hog.  According to the website Food and Water Watch:

  • 20% of the fossil fuel used in the US goes toward food production.
  • This inefficient system spends 10,551 quadrillion joules of energy each year – about the same as used by all of France.
  • The US EPA reported that US agriculture is responsible for the same amount of CO2 emissions per year as 141,000,000 cars.  Emissions DOUBLE when electricity usage is included.

Kenneth Watt, on the very first Earth Day in 1970, said that our very existence is dependent on the massive import of energy into industrial agriculture from petroleum, natural gas and coal – and this massive energy use creates a “fossil fuel subsidy”:  that means the use of petroleum has enabled fewer farmers to produce much more food on less land, so the population can grow.

Petroleum-based agriculture has reduced the proportion of the US population engaged in agriculture from about 50% about 75 years ago to less than 2% today.  In other words, the average American farmer feeds lots of people, as well as having enough left over to ship abroad. Petroleum also lets Floridians eat salmon from Alaska, and Alaskans enjoy orange juice from Florida. Between 1950 and 1970, the last 11 million horses were taken out of American agriculture and replaced by tractors powered by crude oil. Since it takes very roughly four times the acreage to support one horse as a person, this means we have been able to add 44 million people to the American population [in those twenty years] for that one cause alone, because of a fossil fuel subsidy.

According to Kenneth Watt, “mankind is embarked on an absolutely immense gamble. We are letting the population build up and up and up, by increasing the carrying capacity of the Earth for people, using a crude-oil energy subsidy, on the assumption that there’s no inherent danger in this because when the need arises we’ll be able to get ultimate sources of energy.”

But what happens if we don’t have alternate sources of energy,  when the oil crunch appears?  As oil production declines, prices will rise – especially commodities – and most especially food.

So how can organic agriculture help us with this dire picture.  You’ll be surprised!  Check in next week.





Why is recycled polyester considered a sustainable textile?

14 07 2009

plastic_bottles

Synthetic fibers are the most popular fibers in the world – it’s estimated that synthetics account for about 65% of world production versus 35% for natural fibers.[1] Most synthetic fibers (approximately 70%) are made from polyester, and the polyester most often used in textiles is polyethylene terephthalate (PET).   Used in a fabric, it’s most often referred to as “polyester” or “poly”.

The majority of the world’s PET production – about 60% – is used to make fibers for textiles; about 30% is used to make bottles.   It’s estimated that it takes about 104 million barrels of oil for PET production each year – that’s 70 million barrels just to produce the virgin polyester used in fabrics.[2] That means most polyester – 70 million barrels worth –  is manufactured specifically to be made into fibers, NOT bottles, as many people think.  Of the 30% of PET which is used to make bottles, only a tiny fraction is recycled into fibers.  But the idea of using recycled bottles – “diverting waste from landfills” – and turning it into fibers has caught the public’s imagination.

The reason recycled polyester (often written rPET) is considered a green option in textiles today is twofold, and the argument goes like this:

  1. energy needed to make the rPET is less than what was needed to make the virgin polyester in the first place, so we save energy.
  2. And  we’re keeping bottles and other plastics out of the landfills.

Let’s look at these arguments.

1) The energy needed to make the rPET is less than what is needed to make the virgin polyester, so we save energy:

It is true that recycling polyester uses less energy that what’s needed to produce virgin polyester.  Various studies all agree that it takes  from 33%  to 53% less energy[3].  If we use the higher estimate, 53%,  and take 53% of the total amount of energy needed to make virgin polyester (125 MJ per KG of ton fiber)[4], the amount of energy needed to produce recycled polyester in relation to other fibers is:

Embodied Energy used in production of various fibers:

energy use in MJ per KG of fiber:

hemp, organic

2

flax

10

hemp, conventional

12

cotton, organic, India

12

cotton, organic, USA

14

cotton,conventional

55

wool

63

rPET

66

Viscose

100

Polypropylene

115

Polyester

125

acrylic

175

Nylon

250

rPET is also cited as producing far fewer emissions to the air than does the production of  virgin polyester: again estimates vary, but Libolon’s website introducing its new RePET yarn put the estimate at 54.6% fewer CO2 emissions.  Apply that percentage to the data from the Stockholm Environment Institute[5], cited above:

KG of CO2 emissions per ton of spun fiber:

crop cultivation

fiber production

TOTAL

polyester USA

0

9.52

9.52

cotton, conventional, USA

4.2

1.7

5.89

rPET

5.19

hemp, conventional

1.9

2.15

4.1

cotton, organic, India

2

1.8

3.75

cotton, organic, USA

0.9

1.45

2.35

Despite the savings of both energy and emissions from the recycling of PET, the fact is that it is still more energy intensive to recycle PET into a  fiber than to use organically produced natural fibers – sometimes quite a bit more energy.

2) We’re diverting bottles and other plastics from the landfills.

That’s undeniably true,  because if you use bottles then they are diverted!

But the game gets a bit more complicated here because rPET is divided into “post consumer” PET and “post industrial” rPET:  post consumer means it comes from bottles; post industrial might be the unused packaging in a manufacturing plant, or other byproducts of manufacturing.  The “greenest” option has been touted to be the post consumer PET, and that has driven up demand for used bottles. Indeed, the demand for used bottles, from which recycled polyester fibre is made, is now outstripping supply in some areas and certain cynical suppliers are now buying NEW, unused bottles directly from bottle producing companies to make polyester textile fiber that can be called recycled.[6]

Using true post consumer waste means the bottles have to be cleaned (labels must be removed because labels often contain PVC) and sorted.  That’s almost always done in a low labor rate country since only human labor can be used.   Add to that the fact that the rate of bottle recycling is rather low – in the United States less than 6% of all waste plastic gets recycled [7].  The low recycling rate doesn’t mean we shouldn’t continue to try, but in the United States where it’s relatively easy to recycle a bottle and the population is relatively well educated in the intricacies of the various resin codes, doesn’t it make you wonder how successful we might be with recycling efforts in other parts of the world?

pet-recycling-graph-2 SOURCE: Container Recycling Institute

There are two types of recycling:  mechanical and chemical:

    • Mechanical recycling is accomplished by melting the plastic and re-extruding it to make yarns.  However, this can only be done  few times before the molecular structure breaks down and makes the yarn suitable only for the landfill[8] where it may never biodegrade, may biodegrade very slowly, or may add harmful materials to the environment as it breaks down (such as antimony).  William McDonough calls this  “downcycling”.
    • Chemical recycling means breaking the polymer into its molecular parts and reforming the molecule into a yarn of equal strength and beauty as the original.  The technology to separate out the different chemical building blocks (called depolymerization) so they can be reassembled (repolymerization) is very costly and almost nonexistent.

Most recycling is done mechanically (or as noted above, by actual people). Chemical recycling does create a new plastic which is of the same quality as the original,  but the process is very expensive and is almost never done, although Teijin has a new program which recycles PET fibers into new PET fibers.

The real problem with making recycled PET a staple of the fiber industry is this:  recycling, as most people think of it, is a myth.  Most people believe that plastics can be infinitely recycled  – creating new products of a value to equal the old bottles or other plastics which they dutifully put into recycling containers to be collected. The cold hard fact is that there is no such thing as recycling plastic, because it is not a closed loop.  None of the soda and milk bottles which are collected from your curbside are used to make new soda or milk bottles, because each time the plastic is heated it degenerates, so the subsequent iteration of the polymer is degraded and can’t meet food quality standards for soda and milk bottles.  The plastic must be used to make lower quality products.  The cycle goes something like this:

  • virgin PET can be made into soda or milk bottles,
  • which are collected and recycled into resins
    • which are appropriate to make into toys, carpet, filler for pillows, CD cases, plastic lumber products,  fibers or a million other products. But not new soda or milk bottles.
  • These second generation plastics can then be recycled a second time into park benches, carpet, speed bumps or other products with very low value.
  • The cycle is completed when the plastic is no longer stable enough to be used for any product, so it is sent to the landfill
    • where it is incinerated (sometimes for energy generation, which a good LCA will offset)  -
    • or where it will hold space for many years or maybe become part of the Great Pacific Garbage Patch![9]

And there is another consideration in recycling PET:  antimony, which is present in 80 – 85% of all virgin PET[10], is converted to antimony trioxide at high temperatures – such as are necessary during recycling, releasing this carcinogen from the polymer and making it available for intake into living systems.

Using recycled PET for fibers also creates some problems specific to the textile industry:

  • The base color of the recycled polyester chips vary from white to creamy yellow, making color consistency difficult to achieve, particularly for the pale shades.  Some dyers find it hard to get a white, so they’re using chlorine-based bleaches to whiten the base.
  • Inconsistency of dye uptake makes it difficult to get good batch-to-batch color consistency and this can lead to high levels of re-dyeing, another very high energy process.  Re-dyeing contributes to high levels of water, energy and chemical use.
  • Unsubstantiated reports claim that some recycled yarns take almost 30% more dye to achieve the same depth of shade as equivalent virgin polyesters.[11]
  • Another consideration is the introduction of PVC into the polymer from bottle labels and wrappers.
  • Many rPET fibers are used in forgiving constructions such as polar fleece, where the construction of the fabric hides slight yarn variations.  For fabrics such as satins, there are concerns over streaks and stripes.

Once the fibers are woven into fabrics, most fabrics are rendered non-recyclable  because:

  • the fabrics almost always have a chemical backing, lamination or other finish,
  • or they are blends of different synthetics (polyester and nylon, for example).

Either of these renders the fabric unsuitable for the mechanical method of recycling, which cannot separate out the various chemicals in order to produce the recycled yarn; the chemical method could  -   if we had the money and factories to do it.

One of the biggest obstacles to achieving McDonough’s Cradle-to-Cradle vision lies outside the designers’ ordinary scope of interest – in the recycling system itself. Although bottles, tins and newspapers are now routinely recycled, furniture and carpets still usually end up in landfill or incinerators, even if they have been designed to be  recycled [12] because project managers don’t take the time to separate out the various components of a demolition job, nor is collection of these components an easy thing to access.

Currently, the vision that most marketers has led us to believe, that of a closed loop, or cycle, in which the yarns never lose their value and recycle indefinitely is simply that – just a vision.  Few manufacturers, such as Designtex (with their line of EL fabrics designed to be used without backings) and Victor Innovatex (who has pioneered EcoIntelligent™ polyester made without antimony),  have taken the time, effort and money needed to accelerate the adoption of sustainable practices in the industry so we can one day have synthetic fabrics that are not only recycled, but recyclable.


[1] “New Approach of Synthetic Fibers Industry”, Textile Exchange,  http://www.teonline.com/articles/2009/01/new-approach-of-synthetic-fibe.html

[2] Polyester, Absolute Astronomy.com: http://www.absoluteastronomy.com/topics/Polyester and Pacific Institute, Energy Implications of Bottled Water, Gleick and Cooley, Feb 2009, http://www.pacinst.org/reports/bottled_water/index.htm)

[3] Website for Libolon’s RePET yarns:  http://www.libolon.com/eco.php

[4] Data compiled from:  “LCA: New Zealand Merino Wool Total Energy Use”, Barber and Pellow,                                                                       http://www.tech.plym.ac.uk/sme/mats324/mats324A9%20NFETE.htm and  “Ecological Footprint and Water

Analysis of Cotton, Hemp and Polyester”, by Cherrett et al, Stockholm Environment Institute

[5] “Ecological Footprint and Water Analysis of Cotton, Hemp and Polyester”, by Cherrett et al, Stockholm Environment Institute

[6] The Textile Dyer, “Concern over Recycled Polyester”, May 13, 2008,

[7] Watson, Tom, “Where can we put all those plastics?”, The Seattle Times, June 2, 2007

[8] William McDonough and Michael Braungart, “Transforming the Textile Industry”, green@work, May/June 2002.

[9] See www.greatgarbagepatch.org/

[10] Chemical Engineering Progress, May 2003

[11] “Reduce, re-use,re-dye?”,  Phil Patterson, Ecotextile News, August/September 2008

[12] “Taking Landfill out of the Loop”, Sarah Scott, Azure, 2006





Great new idea!

7 07 2009

We just had a spectacularly beautiful July 4th weekend here in Seattle – temperatures were actually above 80, it was sunny and  sparkling.  It was just too much to post yet another bog about the dire state of our environment.  So I was floundering around looking for some great new environmental news to share.  I found some interesting stuff on LiveScience (Top 10 crazy environmental ideas) but Lucy Siegle’s list of 20 great ideas  in the Observer had  one that really got my heart pumping!

The idea in a nutshell:  rather than boycott a business – procott instead!

“The problem is that businesses will do anything for money,” says 27-year-old US environmentalist Brent Schulkin. “But what if that’s also the solution?”  This idea is not brand new – Diane MacEachern founded The Big Green Purse to empower consumers (especially women) to use their buying clout to protect the environment.  But Schulkin’s plan has an added dimension – that of adding the value of organization.

His idea was to encourage profit-hungry companies to do good by promising to spend more money with them. But he wouldn’t be making all the purchases himself; he’d bring a mob.

That was the inspiration for Carrotmob, his loosely organized group of conscious consumers.

According to  Schulkin, there’s an old saying that there are two ways to make a donkey walk forward: Either offer a delicious carrot out in front of it, or hit its behind with a stick. Think of businesses as the donkeys. Traditional consumer activism uses a lot of sticks, such as protests, lawsuits, boycotts, and so on. Schulkin’s idea is to use the carrot instead. Schulkin believes that we can get businesses to make big positive changes by offering them profits in return. It’s a positive model where there are no enemies and everyone wins.

To put his idea into practice, Schulkin visited 23 liquor stores in his Mission District neighborhood, and asked each one how much money they’d be willing to set aside for energy efficiency improvements from the profits of Carrotmob’s spending. The bidding started at 10%, and increased slightly until K&D Market offered the winning bid of 23%.

Next experts came in to inspect K&D and to offer suggestions for energy improvements. Using the internet, Schulkin puclicized the event  and nervously waited to see if any shoppers would show up.

With a bouncer at the door to ensure a safe number of people inside the little market, the line stretched to the end of the block. Store staff continuously restocked the shelves with liquor, cereal, organic peanut butter, tuna fish and other canned food. At the end of the day there were two overflowing barrels of donations for the San Francisco Food Bank and market receipts totaling $9,276, several thousands of dollars more than usual.

Schulkin’s idea is that we buy products anyway, so why not from a company that is doing good?  Ultimately he wants to create carrotmobs so big that they can negotiate with some of the globe’s biggest corporations.





Only two days to go!

7 07 2009

Shortly after noon on July 8 comes the moment when it will be, precisely,

12:34:56 7/8/9!