ISIS Report 29/06/05
Making the World Sustainable
Group, Dept. of Pharmacy, Kings College, Franklin-Wilkins Bldg.
London SE1 9NN, UK.
Institute of Science in Society, PO Box 32097, London NW1 0XR, UK
E-mail: [email protected]
Plenary lecture at Food Security in An Energy-Scarce World
international conference, 23-25 June 2005, University College, Dublin, Ireland.
A fuller version with
references and figures
are posted on ISIS Members website.
Decades of an "environmental bubble economy" built on the
over-exploitation of natural resources has accelerated global warming,
environmental degradation, depletion of water and oil, and brought falling crop
yields, precipitating a crisis in world food security with no prospects for
improvement under the business as usual scenario.
There is, nevertheless, a wealth of knowledge for making our food system
sustainable that not only can provide food security and health for all, but can
also go a long way towards mitigating global warming by preventing greenhouse
gas emissions and creating new carbon stocks and sinks.
One of the most important obstacles to implementing the existing
knowledge is the dominant economic model of unrestrained, unbalanced growth
that has already failed the reality test. I describe a highly productive
integrated farming system based on maximising internal input to illustrate a
theory of sustainable organic growth as alternative to the dominant model.
Current food production system due for collapse
World grain yield fell for four successive years from 2000 to 2003 as
temperatures soar, bringing reserves to the lowest in thirty years . The
situation did not improve despite a bumper harvest in 2004, which
was just enough to satisfy world consumption. Experts are predicting  that
global warming is set to do far worse damage to food production than "even the
gloomiest of previous forecasts." An international team of crop scientists from
China, India, the Philippines and the United States had already reported that
crop yields fall by 10 percent for each deg. C rise in night-time temperature
during the growing season .
The Intergovernment Panel on Climate Change (IPCC) predicted in 2001
that the earths average temperature would rise by 1.4 to 5.8 deg. C
within this century . In 2003, a Royal Society conference in London told us
that the IPCC model fails to capture the abrupt nature of climate change, that
it could be happening over a matter of decades or years . In January 2005, a
group based in Oxford University in the UK predicts a greater temperature rise
of 1.9 to 11.5 deg. C when carbon dioxide level in the atmosphere, currently
standing at 379 parts per million, doubles its pre-industrial level of 280
parts per million sometime within the present century .
The "environmental bubble economy" built on the unsustainable
exploitation of our natural resources is due for collapse  said Lester Brown
of Earth Policy Institute. The task of turning our food production system
sustainable must be addressed at "war-time" speed.
He summarised the fallout of the environmental bubble economy succinctly
: "..collapsing fisheries, shrinking forests, expanding deserts, rising
eroding soils, rising temperatures, falling water tables, melting glaciers,
deteriorating grasslands, rising seas, rivers that are running dry, and
In too many of the major food-production regions of the world, such as
the bread baskets of China, India and the United States, conventional farming
practices including heavy irrigation have severely depleted the underground
water [7, 8]. At the same time, world oil production may have passed its peak
; oil price hit a record high of US$58 a barrel on 4 April 2005, and is
expected to top US$100 within two years . This spells looming disaster for
conventional industrial agriculture, which is heavily dependent on both oil and
Our current food production system is a legacy of the high input
agriculture of the green revolution, exacerbated and promoted by agricultural
policies that benefit trans-national agribusiness corporations at the expense
of farmers [11, 12]. Its true costs are becoming all too clear (see Box 1).
True costs of industrial food production system
- 1 000 tonnes of water are consumed to produce one tonne of
- 10 energy units are spent for every energy unit of food on our
dinner table [14, 15]
- Up to 1 000 energy units are used for every energy unit of
processed food 
- 17% of the total energy use in the United States goes into food
production & distribution, accounting for more than 20% of all transport
within the country; this excludes energy used in import and export 
- 12.5 energy units are wasted for every energy unit of food
transported per thousand air-miles [18, 19]
- Current EU and WTO agricultural policies maximise food miles
resulting in scandalous "food swaps" [20, 21]
- Up to 25% of CO2, 60% of CH4 and 60% of N2O in the world come from current
- US$318 billion of taxpayers money was spent to subsidize
agriculture in OECD countries in 2002, while more than 2 billion subsistence
farmers in developing countries tried to survive on $2 a day [11, 23]
- Nearly 90% of the agricultural subsidies benefit corporations
and big farmers growing food for export; while 500 family farms close down
every week in the US 
- Subsidized surplus food dumped on developing countries creates
poverty, hunger and homelessness on massive scales 
Benefits of sustainable food production systems for everyone
Getting our food production sustainable is the most urgent task for
humanity; it is also the key to delivering health, mitigating global warming
and saving the planet from destructive exploitation. As Gustav Best, Senior
Energy Coordinator of FAO pointed out , agriculture is impacted by climate
change, it contributes a great deal of greenhouse gases directly, but properly
done, it goes a long way towards mitigating climate change.
The benefits of sustainable food systems are becoming evident  (see
Box 2). There are major opportunities to reduce energy use, to make our food
system much more energy efficient, and even to extract energy through
converting agricultural wastes into rich fertilizers to increase productivity,
that at the same time, reduces greenhouse gas emissions while increasing carbon
stocks and sinks.
Some benefits of sustainable food production systems
- 2- to 7-fold energy saving on switching to low-input/organic
agriculture [17, 25]
- 5 to 15% global fossil fuel emissions offset by sequestration
of carbon in organically managed soil 
- 5.3 to 7.6 tonnes of carbon dioxide emission disappear with
every tonne of nitrogen fertilizer phased out 
- Up to 258 tonnes of carbon per hectare can be stored in
tropical agro-forests , which in addition, sequester 6 tonnes of carbon per
hectare per year 
- Biogas digesters provide energy and turn agricultural
wastes into rich fertilizers for zero-input, zero-emission farms 
- 625 thousand tonnes of carbon dioxide emissions prevented each
year in Nepal through harvesting biogas from agricultural wastes 
- 2- to 3-fold increase in crop yield using compost in Ethiopia,
outperforming chemical fertilizers 
- Organic farming in the US yields comparable or better than
conventional industrial farming [33, 34], especially in times of drought
- Organic farms in Europe support more birds, butterflies,
beetles, bats, and wild flowers than conventional farms 
- Organic foods contain more vitamins, minerals and other
micronutrients, and more antioxidants than conventionally produced foods
- 1 000 or more community-supported farms across US and Canada
bring $36m income per year directly to the farms 
- £50-78m go directly into the pocket of farmers trading in
some 200 established local farmers markets in the UK 
- Buying food in local farmers market generates twice as
much for the local economy than buying food in supermarkets chains 
- Money spent with a local supplier is worth four times as much
as money spent with non-local supplier 
Dominant model unsustainable
There is a wealth of existing knowledge that could provide food security
and health for all and significantly mitigate global warming. Unfortunately,
our elected representatives are overwhelmingly committed to the neo-liberal
economic model that created the bubble-economy in the first place. They lack
the wisdom and the political will to make the structural and policy change
required for implementing the knowledge. That is why the Institute of Science
in Society (ISIS) and the Independent Science Panel (ISP) have launched a
Sustainable World Global Initiative to create an opportunity for scientists
across the disciplines to join forces with all sectors of civil society in a
bid to make our food system sustainable . We aim to produce a comprehensive
report at the end of the year that will lay out the existing knowledge base as
well as the socioeconomic and political policy and structural changes needed to
implement sustainable food systems for all. The launch conference takes place
in UK Parliament 14 July 2005 (http://www.i-sis.org.uk/isp/SustainableWorld2ndAnnouncement.php).
The dominant economic model glorifies competitiveness and unlimited
growth involving the most dissipative and destructive exploitation of the
earths natural resources that have laid waste to agricultural land and
A study for the International Food Policy Research Institute reveals
that each year, 10 million hectares of cropland worldwide are abandoned due to
soil erosion, and another 10 million hectares are critically damaged by
salination as a result of irrigation and/or improper drainage methods. This
amounts to more than 1.3 percent of total cropland lost annually; and replacing
lost cropland accounts for 60% of the massive deforestation now taking place
worldwide . Clearing forests releases their massive carbon stocks to the
atmosphere, turning important carbon stocks and sinks into sources. Some
estimates have placed the total carbon stock of secondary tropical forests as
high as 418 tonnes of C per hectare including soil organic carbon, and carbon
is sequestered at 5 tonnes C per hectare per year . Change in land use such
as this accounts for 14% of the global total greenhouse gas emission .
The World Health Organisation estimates that more than 3 billion people
are malnourished (lacking in calories, protein, iron, iodine and/or vitamins A,
B, C, and D), of which 850 million actually suffer from hunger (protein-energy
malnutrition) . The principal cause of hunger is poverty. Some 1.08 billion
poor people in developing countries live on $1 or less a day; of these, 798
million are chronically hungry.
Continued commitment to the dominant economic model that has so
glaringly failed the reality test - is perhaps the greatest obstacle to
implementing sustainable food systems. There are already many success stories
from the grassroots, and I shall describe one of them  briefly. It
illustrates most concretely an alternative model of sustainable, balanced
growth that I have been elaborating over the past 8 years [48-51], and
presented in its most definitive form recently in collaboration with ecologist
Robert Ulanowicz .
Environmental engineer meets Chinese peasant farmers
It may sound like a dream, but it is possible to produce a
super-abundance of food with no fertilizers or pesticides and with little or no
greenhouse gas emission. The key is to treat farm wastes properly to mine the
rich nutrients that can be returned to the farm, to support the production of
fish, crops, livestock and more; get biogas energy as by-product, and perhaps
most importantly, conserve and release pure potable water back to the
Professor George Chan has spent years perfecting the system; and refers
to it as the Integrated Food and Waste Management System (IFWMS) . I just
call it "dream farm" .
Chan was born in Mauritius and educated at Imperial College, London
University in the UK, specializing in environmental engineering. He was
director of two important US federal programmes funded by the Environmental
Protection Agency and the Department of Energy in the US Commonwealth of the
Northern Mariana Islands of the North Pacific. On retiring, Chan spent 5 years
in China among the Chinese peasants, and confessed he learned just as much
there as he did in University.
He learned from the Chinese peasants a system of farming and living
that inspired him and many others including Gunter Pauli, the founder and
director of the Zero Emissions Research Initiative (ZERI) (www.zeri.org). Chan has worked with ZERI since,
which has taken him to nearly 80 countries and territories, and contributed to
evolving IFWMS into a compelling alternative to conventional farming.
The integrated farm typically consists of crops, livestock and
fishponds. But the nutrients from farm wastes often spill over into supporting
extra production of algae, chickens, earthworms, silkworms, mushrooms, and
other valuables that bring additional income and benefits for the farmers and
the local communities.
Treating wastes with respect
The secret is in treating wastes to minimize the loss of valuable
nutrients that are used as feed. At the same time, greenhouse gases emitted
from farm wastes are harvested for use as fuel.
Livestock wastes are first digested anaerobically (in the absence of
air) to harvest biogas (mainly methane, CH4). The partially digested
wastes are then treated aerobically (in the presence of air) in shallow basins
that support the growth of green algae. By means of photosynthesis, the algae
produce all the oxygen needed to oxidise the wastes to make them safe for fish.
This increases the fertilizer and feed value in the fishponds without robbing
the fish of dissolved oxygen. All the extra nutrients go to increase
productivity, which is standing carbon stock, preventing carbon dioxide
(CO2) going to
the atmosphere. Biogas is used, in turn, as a clean energy source for cooking.
This alone, has been a great boon to women and children , above all, saving
them from respiratory diseases caused by inhaling smoke from burning firewood
and cattle dung. It also spares the women the arduous task of fetching 60 to 70
lb of firewood each week, creating spare time for studying in the evening or
earning more income. Biogas energy also enables farmers to process their
produce for preservation and added value, reducing spoilage and increasing the
The system has revolutionized farming of livestock, aquaculture,
horticulture, agro-industry and allied activities in some countries especially
in non-arid tropical and subtropical regions. It has solved most of the
existing economic and ecological problems and provided the means of production
in the form of fuel, fertilizer and feed, increasing productivity many-fold.
"It can turn all those existing disastrous farming systems, especially
in the poorest countries into economically viable and ecologically balanced
systems that not only alleviate but eradicate poverty." Chan says .
Increasing the recycling of nutrients for greater productivity
The ancient practice of combining livestock and crop had helped farmers
almost all over the world. Livestock manure is used as fertilizer, and crop
residues are fed back to the livestock.
Chan points out, however, that most of the manure, when exposed to the
atmosphere, lost up to half its nitrogen as ammonia and nitrogen oxides before
they can be turned into stable nitrate that plants use as fertilizer. The more
recent integration of fish with livestock and crop has helped to reduce this
Adding a second production cycle of fish and generating further
nutrients from fish wastes has enhanced the integration process, and improved
the livelihoods of many small farmers considerably. But too much untreated
wastes dumped directly into the fishpond can rob the fish of oxygen, and end up
killing the fish.
In IFWMS, the anaerobically digested wastes from livestock are treated
aerobically before the nutrients are delivered into the fishponds to fertilize
the natural plankton that feed the fish without depleting oxygen, thereby
increasing fish yield 3- to 4-fold, especially with the polyculture of many
kinds of compatible fish feeding at different trophic levels as practiced in
China, Thailand, Vietnam, India and Bangladesh. The fish produce their own
wastes that are converted naturally into nutrients for crops growing both on
the water surface and on dykes surrounding the ponds.
The most significant innovation of IFWMS is thus the two-stage method
of treating wastes. Livestock waste contains very unstable organic matter that
decomposes fast, consuming a lot of oxygen. So for any fish pond, the quantity
of livestock wastes that can be added is limited, as any excess will deplete
the oxygen and affect the fish population adversely, even killing them.
Chan is critical of "erratic proposals" of experts, both local and
foreign, to spread livestock wastes on land to let them rot away and hope that
the small amount of residual nutrients left after tremendous losses that damage
the environment have taken place.
According to the US Environment Protection Agency, up to 70% of nitrous
oxide, N2O, a
powerful greenhouse gas with a global warming potential of 280 (i.e., 280 times
that of carbon dioxide) comes from conventional agriculture . Nitrous oxide
is formed as an intermediate both in nitrification oxidising ammonia
nitrate (NO3-) and
denitrification, reducing nitrate ultimately back to nitrogen gas. Both
processes are carried out by different species of soil bacteria. Animal manure
could be responsible for nearly half of the N2O emission in agriculture
in Europe, according to some estimates; the remainder coming from inorganic
nitrate fertilizer . Thus, anaerobic digestion not only prevents the loss
of nutrients, it could also substantially reduce greenhouse gas emissions from
agriculture in the form of both methane (harvested as biogas) and nitrous oxide
(saved as nutrient).
Chan further dismisses the practice of composting nutrient-rich
livestock wastes , for this ends up with a low-quality fertilizer that has
lost ammonia, nitrite (NO) and nitrous oxide. Instead of mixing livestock
wastes with household garbage in the compost, Chan recommends producing
high-protein feeds such as earthworms from the garbage, and using worm castings
and garbage residues as better soil conditioners.
To close the circle, which is very important for sustainable
growth, livestock should be fed crops and processing residues, not wastes
from restaurants and slaughterhouses. Earthworms, silkworms, fungi, insects and
other organisms are also encouraged, as some of them are associated with
producing high value goods such as silk and mushrooms.
Proliferating lifecycles for greater productivity
The aerobic treatment in the shallow basins depends on oxygen produced
by the green alga Chlorella. Chlorella is very prolific and can
be harvested as a high-protein feed for chickens, ducks and geese.
When the effluent from the Chlorella basins reaches the
fishpond, little or no organic matter from the livestock waste will remain, and
any residual organic matter will be instantly oxidized by some of the dissolved
oxygen. The nutrients are now readily available for enhancing the prolific
growth of different kinds of natural plankton that feed the polyculture of 5 to
6 species of compatible fish. No artificial feed is necessary, except locally
grown grass for any herbivorous fish.
The fish waste, naturally treated in the big pond, gives nutrients that
are effectively used by crops growing in the pond water and on the dykes
Fermented rice or other grain, used for producing alcoholic beverages,
or silkworms and their wastes, can also be added to the ponds as further
nutrients, resulting in higher fish and crop productivity, provided the water
quality is not affected.
Trials are taking place with special diffusion pipes carrying
compressed air from biogas-operated pumps to aerate the bottom part of the
pond; to increase plankton and fish yields.
Apart from growing vine-type crops on the edges of the pond and letting
them climb on trellises over the dykes and over the water, some countries grow
aquatic vegetables floating on the water surfaces in lakes and rivers. Others
grow grains, fruits and flowers on bamboo or long-lasting polyurethane floats
over nearly half the surface of the fishpond water without interfering with the
polyculture in the pond itself. Such aquaponic cultures have increased the crop
yields by using half of the millions of hectares of fishponds and lakes in
China. All this is possible because of the excess nutrients created from the
integrated farming systems.
Planting patterns have also improved. For example, rice is now
transplanted into modules of 12 identical floats, one every week, and just left
to grow in the pond without having to irrigate or fertilize separately, or to
do any weeding, while it takes 12 weeks to mature. On the 13th week,
the rice is harvested and the seedlings transplanted again to start a new
cycle. It is possible to have 4 rice crops yearly in the warmer parts of the
country, with almost total elimination of the back breaking work previously
Another example is hydroponic cultures of fruits and vegetables in a
series of pipes. The final effluent from the hydroponic cultures is polished in
earthen drains where plants such as Lemna, Azolla, Pistia
and water hyacinth remove all traces of nutrients such as nitrate, phosphate
and potassium before the purified water is released back into the aquifer.
The sludge from the anaerobic digester, the algae, crop and processing
residues are put into plastic bags, sterilized in steam produced by biogas
energy, and then injected with spores for culturing high-priced mushrooms.
The mushroom enzymes break down the ligno-cellulose to release the
nutrients and enrich the residues, making them more digestible and more
palatable for livestock. The remaining fibrous residues also can still be used
for culturing earthworms, which provide special protein feed for chickens. The
final residues, including the worm casting, are composted and used for
conditioning and aerating the soil.
Sustainable development & human capital
There has been a widespread misconception that the only alternative to
the dominant model of infinite, unsustainable growth is to have no growth at
all. I have heard some critics refer to sustainable development as a
contradiction in terms. IFWMS, however, is a marvellous demonstration that
sustainable development is possible. It also shows that the carrying capacity
of a piece of land is far from constant; instead it depends on the mode of
production, on how the use of the land is organised. Productivity can vary
three- to four-fold or more simply by maximising internal input, and in the
process, creating more jobs, supporting more people.
The argument for population control has been somewhat over-stated by
Lester Brown [7, 8] and in several contributions to the present conference
predicting massive starvation and population crash as oil runs out. I like the
idea of "human capital" to counter that argument, if only to restore a sense of
balance that it isnt population number as such, but the glaring
inequality of consumption and dissipation by the few rich in the richest
countries thats responsible for the current crises. The way Cuba coped
with the sudden absence of fossil fuel, fertilizer and pesticides by
implementing organic agriculture across the nation is a case in point .
There was no population crash; although there was indeed hardship for a while.
It also released creative energies, which brought solutions and many
accompanying ecological and social benefits.
For the past 50 years, the world has opted overwhelmingly for an
industrial food system that aspired to substitute machines and fossil fuel for
human labour, towards agriculture without farmers. This has swept people off
the land and into poverty and suicide. One of the most urgent tasks ahead is to
re-integrate people into the ecosystem. Human labour is intelligent energy,
applied precisely and with ingenuity, which is worth much more than appears
from the bald accounting in Joules or any other energy unit. This is an
important area for future research.
Sustainable development is possible
Let me clarify my main message with a few diagrams. The dominant model
of infinite unsustainable growth is represented in Figure 1. The system grows
relentlessly, swallowing up the earths resources without end, laying
waste to everything in its path, like a hurricane. There is no closed cycle to
hold resources within, to build up stable organised structures.
Figure 1. The dominant economic model of infinite
unsustainable growth that swallows up the earths resources and exports
massive amounts of wastes and entropy
In contrast, a sustainable system is like an organism [48-52], it
closes the cycle to store as much as possible of the resources inside the
system, and minimise waste (see Figure 2). Closing the cycle creates at the
same time a stable, autonomous structure that is self-maintaining,
self-renewing and self-sufficient.
Figure 2. The sustainable system closes the energy and
resource use cycle, maximising storage and internal input and minimising waste,
rather like the life cycle of an organism that is autonomous and
In many indigenous integrated farming systems, livestock is
incorporated to close the circle (Figure 3), thereby minimizing external input,
while maximising productivity and minimizing wastes exported to the
Figure 3. Integrated farming system that closes the
cycle thereby minimizing input and waste
The elementary integrated farm supports three lifecycles within it,
linked to one another; each lifecycle being autonomous and self-renewing. It
has the potential to grow by incorporating yet more lifecycles (Figure 4). The
more lifecycles incorporated within the system, the greater the productivity.
That is why productivity and biodiversity always go together .
Industrial monoculture, by contrast, is the least energy efficient in terms of
output per unit of input , and less productive in absolute terms despite
high external inputs, as documented in recent academic research .
Figure 4. Increasing productivity by incorporating
more lifecycles into the system
Actually the lifecycles are not so neatly separated, they are linked by
many inputs and outputs, so a more accurate representation would look something
like Figure 5 [49, 50, 52].
Figure 5. The many-fold coupled lifecycles in a highly
productive sustainable system
The key to sustainable development is a balanced growth
thats achieved by closing the overall production cycle, then using the
surplus nutrients and energy to support increasingly more cycles of activities
while maintaining internal balance and nested levels of autonomy, just like a
developing organism [49, 50, 52]. The waste from one production
activity is resource for another, so productivity is maximised with the minimum
of input, and little waste is exported into the environment. It is possible to
have sustainable development after all; the alternative to the dominant model
of unlimited, unsustainable growth is balanced growth.
The same principles apply to ecosystems  and economic systems [50,
51] that are of necessity embedded in the ecosystem (Figure 6).
Figure 6. Economic system coupled to and embedded in
Deconstructing money and the bubble economy
Economics immediately brings to mind money. The circulation of money in
real world economics is often equated with energy in living systems. I have
argued however, that all money is not equal [50, 51]. The flow of money can be
associated with exchanges of real value or it can be associated with sheer
wastage and dissipation; in the former case, money is more like energy, in the
latter case, it is pure entropy. Because the economic system depends ultimately
on the flow of resources from the ecosystem, entropic costs can either be
incurred in the economic system itself, or in the ecosystem, but the net result
is the same.
Thus, when the cost of valuable (non-renewable) ecosystem resources
consumed or destroyed are not properly taken into account, the entropic burden
falls on the ecosystem. But as the economic system is coupled to and dependent
on input from the ecosystem, the entropic burden exported to the ecosystem will
feedback on the economic system as diminished input, so the economic system
becomes poorer in real terms.
On the other hand, transaction in the financial or money market creates
money that could be completely decoupled from real value, and is pure entropy
produced within the economic system. This artificially increases purchasing
power, leading to over-consumption of ecosystem resources. The unequal terms of
trade, which continues to be imposed by the rich countries of the North on the
poor countries of the South through the World Trade Organisation, is another
important source of entropy. That too, artificially inflates the purchasing
power of the North, resulting in yet more destructive exploitation of the
earths ecosystem resources in the South.
It is of interest that recent research in the New Economics Foundation
shows how money spent with a local supplier is worth four times as much as
money spent with non-local supplier , which bears out my analysis. It lends
support to the idea of local currencies and the suggestion for linking energy
with money directly . It also explains why growth in monetary terms not
only fails to bring real benefits to the nation, but end up impoverishing it in
real terms [65, 66].
Lester Brown argues  that the economy must be "restructured" at
"wartime speed" by creating an "honest market" that "tells the ecological
truth". I have provided a sustainable growth model that shows why the dominant
model fails, and why telling the ecological truth is so important.
I am indebted to FESTA for inviting me to present a lecture at the
conference, Food Security in An Energy-Scarce World, which resulted in
the present paper. It benefited a great deal from the formal presentations as
well as discussions with Richard Douthwaite, Folke Gunther, Colin Hines, Julian
Darley, David Fleming, James Bruges, Bruce Darrell and numerous others.