- Sugar has for generations sweetened our palates and expanded
our waistlines. But it is not only our health that has suffered from the
global cultivation of sugar cane. Studies conducted over recent years have
shown that the crop has also been bad for two of the most important and
unique ecosystems in the world - the Florida everglades and the Great Barrier
Reef in Australia.
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- Until the advent of sugar cane, the Florida Everglades
was a vast swampland radiating from Lake Okeechobee, one of America's largest
freshwater lakes. Marjory Stoneman Douglas, campaigner and author of many
books on the Everglades, says: "Nowhere else is like them ... the
miracle of the light pours over the green and brown expanse of saw grass
and water ... it is a river of grass."
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- The Everglades were home to numerous species, from West
Indian manatees to wood storks, Cape Sable seaside sparrows to snail kites.
Now there are fewer than 30 Florida panthers left - a reddish-brown cougar
indigenous to south-west Florida - in fact, there are more statues of the
cat than there are real ones. Fifty-six species living in the Everglades
are either on the endangered or threatened list, the highest number in
the country. Since 1930 there has been a 90 per cent decrease in the number
of wading birds, such as white ibis and roseate spoonbills. During the
past 30 years, all animal species have declined by between 75 and 90 per
cent.
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- The problem is largely due to the way in which sugar
cane is farmed. The Everglades Agricultural Area (EAA) was created out
of drained land, 80 per cent of which is used to cultivate sugar cane.
At 283,000 hectares, it is the largest area set aside for farming in the
world. But it wasn't until 1981 that scientists began to realise what such
cultivation was doing to the environment. Phosphorus and nitrates from
fertilisers used for sugar cane have been pouring into drainage canals
and thus into national parks. As a result of the extra fertilisers, species
such as cattails, a native grass, have grown rampantly, choking the Everglades
and preventing wading birds from feeding.
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- Dr John Ogden, a biologist from South Florida water management
district, has noticed an even more fundamental change at the very heart
of this complex ecosystem. One of the major components of the Everglades
is a slimy substance coating the plants in the marshes. It's made up of
different types of freshwater algae and is food for many tiny freshwater
creatures and fish that other larger animals feed on; in other words, it
is the basis of the whole food chain in the Everglades. But recently, the
change in the water chemistry has altered the composition of these algal
colonies and now the creatures that once fed upon them are unable to do
so.
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- There seems little hope for the future. The power of
sugar companies in the state is legendary: half-way through 2003, Governor
Jeb Bush passed a law pushed through by the US Sugar Corp that relaxed
requirements to clean up the Everglades. Essentially the bill allows water-quality
standards to be reduced, which means levels of phosphorus do not have to
be dramatically lowered for some time.
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- Alan Farago, chair of the Florida branch of the Sierra
Club, an environmental organisation, says: "We understand politics
perfectly well. We understand that big money and big influence can buy
just about anything in the state of Florida, including the redefinition
of pollution so that polluters can continue to pollute."
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- On the other side of the world, the situation is no less
acute. The Great Barrier Reef is also affected by run-off from sugar cane
plantations. Production has expanded rapidly - 400,000 hectares are currently
under cultivation. The result is that soil is quickly eroded and runs into
the wetlands, rivers, streams and ultimately the sea. In sugar cane regions,
losses of 380 tons per hectare have been recorded, compared with only four
in natural rainforests. Since the 1950s, fertiliser has been used in ever-increasing
amounts to keep sugar cane yields high, and this too washes into waterways.
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- The impact is immense: in 2003 a report by an independent
panel of experts commissioned by the Queensland government showed that
run-off from sugar cane plantations was the main cause of decline of up
to 60 per cent of coral species in the inner section of the Great Barrier
Reef. The high levels of nutrients from the fertilisers that wash into
the sea promote the growth of plankton, which supports larger numbers of
filter feeders, such as tubeworms and sponges, and these animals compete
with coral for space.
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- But not everything is doom and gloom. Some 65 per cent
of sugar cane grown here is now cultivated in a more environmentally friendly
way. Traditionally, cane is burnt before it is harvested, to kill pests
and make the fields more manageable for tilling after the harvest. However,
"green cane", harvested without burning, is actually fresher
and contains at least 6 per cent more sucrose. If the "trash",
such as the leaves, is left on the soil, soil structure and fertility improves.
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- Over a five-year cycle of cane growth, fields treated
in this way only lose 10 tons of soil per hectare on average per year.
Nutrient loss, including fertiliser, is also reduced. Nevertheless, more
than 20,000 tons of nitrates still pour onto the barrier reef, a quarter
of which comes from sugar cane agriculture.
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- Sugar derived from sugar beet, a turnip-like tuber, is
little better for the environment. Like sugar cane it is grown in a monoculture
creating a sterile environment for wildlife. Beet is also fed heavily with
fertiliser and pesticides: farmers in Britain use 10.5 active herbicide
ingredients per year, more than twice as much as is used on any other crop.
According to the Soil Association, these practices particularly affect
birds which live and nest in this habitat: for instance, between 1987 and
1998 the numbers of breeding lapwings declined by 50 per cent in Britain.
Water demand is three times higher for beet than for cane, and the crop
is one of the major causes of soil erosion in the UK - we lose more than
350,000 tons every time beet is harvested.
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- In response, Broom's Barn, the national centre for sugar
beet research in Suffolk, has been conducting trials on genetically manipulated
beet that is herbicide resistant. It needs 90 per cent less weed-killer,
which could help make it more wildlife-friendly. "Frequent spraying
destroys the weeds on which the insects and birds feed," says Broom's
Barn's director, Dr John Pidgeon. "But our system means we can reduce
the amount of spraying and allow weeds in between the rows to flourish
in summer without affecting yield. We are very excited about our results
because this is the first time research has shown that GM herbicide-tolerant
crops can be managed for environmental benefit."
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- He hopes that, if trials are approved, the GM sugar will
be on sale by 2007; though whether this will sweeten the unpalatable effects
of sugar on the environment remains to be seen.
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- © 2004 Independent Digital (UK) Ltd
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- http://news.independent.co.uk/world/science_technology/story.jsp?story=590707
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