CHEMICAL FERTILISERS OR THE NATURAL
APPROACH
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A
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The world’s
population continues to climb. And despite the rise of high-tech
agriculture, 800 million people don’t get enough to eat. Clearly, it’s time
to rethink the food we eat and where it comes from. Feeding 9 billion
people will take more than the same old farming practices, especially if we
want to do it without felling rainforests and planting every last scrap of
the prairie. Finding food for all those people will tax predicting
farmers’—and researchers’—ingenuity to the limit. Yet already, precious
aquifers that provide irrigation water for some of the world’s most
productive farmlands are drying up or filling with seawater, and arable
land in China is eroding to create vast dust storms that redden sunsets as
far away as North America. “Agriculture must become the solution to
environmental problems in 50 years. If we don’t have systems that make the
environment better~not just hold the fort-then we’re in trouble,” says
Kenneth Cassman, an agronomist at the University of Nebraska at Lincoln.
That view was echoed in January by the Curry report, a government panel
that surveyed the future of farming and food in Britain.
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B
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It’s easy to say agriculture
has to do better, but what should this friendly farming of the future look
like? Concerned consumers come up short at this point, facing what appears
to be an ever-widening ideological divide. In one corner are the techno-optimists
who put their faith in genetically modified crops, improved agrochemicals,
and computer-enhanced machinery; in the other are advocates of organic
farming, who reject artificial chemicals and embrace back-to-nature
techniques such as composting. Both sides cite plausible science to back
their claims to the moral high ground, and both bring enough passion to the
debate for many people to come away thinking we’re faced with a stark
choice between two mutually incompatible options.
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C
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Not so. If
you take off the ideological blinkers and simply ask how the world can
produce the food it needs with the least environmental cost, a new middle
way opens. The key is sustainability: whatever we do must not destroy the
capital of soil and water we need to keep on producing. Like today’s
organic farming, the intelligent farming of the future should pay much more
attention to the health of its soil and the ecosystem it’s part of. But
intelligent farming should also make shrewd and locally appropriate use of
chemical fertilizers and pesticides. The most crucial ingredient in this
new style of agriculture is not chemicals but information about what’s
happening in each field and how to respond. Yet ironically, this key
element may be the most neglected today.
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D
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Clearly, organic farming has
all the warm, fuzzy sentiment on its side. An approach that eschews
synthetic chemicals surely runs no risk of poisoning land and water. And
its emphasis on building up natural ecosystems seems to be good for
everyone. Perhaps these easy assumptions explain why sales of organic food
across Europe are increasing by at least 50 per cent per year.
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E
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Going organic
sounds idyllic-but it’s naive, too. Organic agriculture has its own suite
of environmental costs, which can be worse than those of conventional
farming, especially if it were to become the world norm. But more
fundamentally, the organic versus-chemical debate focuses on the wrong
question. The issue isn’t what you put into a farm, but what you get out of
it, both in terms of crop yields and pollutants, and what condition the
farm is in when you’re done.
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F
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Take chemical fertilizers,
which deliver nitrogen, an essential plant nutrient, to crops along with
some phosphorus and potassium. It is a mantra of organic farming that these
fertilizers are unwholesome, and plant nutrients must come from natural
sources. But in fact, the main environmental damage done by chemical
fertilizers as opposed to any other kind is through greenhouse gases-carbon
dioxide from the fossil fuels used in their synthesis and nitrogen oxides
released by their degradation. Excess nitrogen from chemical fertilizers
can pollute groundwater, but so can excess nitrogen from organic manures.
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G
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On the other
hand, relying solely on chemical fertilizers to provide soil nutrients
without doing other things to build healthy soil is damaging. Organic
farmers don’t use chemical fertilizers, so they are very good at building
soil fertility by working crop residues and manure into the soil, rotating
with legumes that fix atmospheric nitrogen, and other techniques.
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H
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generates vital soil nutrients
and also creates a soil that is richer in organic matter, so it retains
nutrients better and is hospitable to the crop’s roots and creatures such
as earthworms that help maintain soil fertility. Such soil also holds water
better and therefore makes more efficient use of both rainfall and
irrigation water. And organic matter ties up C02 in the soil, helping to
offset emissions from burning fossil fuels and reduce global warming.
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I
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Advocates of
organic farming like to point out that fields managed in this way can
produce yields just as high as fields juiced up with synthetic fertilizers.
For example, Bill Liebhardt, a research manager at the Rodale Institute in
Kutztown, Pennsylvania recently compiled the results of such comparisons
for corn, wheat, soybeans, and tomatoes in the US and found that the
organic fields averaged between 94 and 100 per cent of the yields of nearby
conventional crops.
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J
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But this optimistic picture
tells only half the story. Farmers can’t grow such crops every year if they
want to maintain or build soil nutrients without synthetic fertilizers.
They need to alternate with soil-building crops such as pasture grasses and
legumes such as alfalfa. So in the long term, the yield of staple grains
such as wheat, rice and corn must go down. This is the biggest cost of
organic farming. Vaclav Smil of the University of Manitoba in Winnipeg,
Canada, estimates that if farmers worldwide gave up the 80 million tonnes
of synthetic fertilizer they now use each year, total grain production
would fall by at least half. Either farmer would have to double the amount
of land they cultivate- at catastrophic cost to natural habitat –or
billions of people would starve.
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K
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That doesn’t
mean farmers couldn’t get by with less fertilizer. Technologically advanced
farmers in wealthy countries, for instance, can now monitor their yields
hectare by hectare, or even more finely, throughout a huge field. They can
then target their fertilizer to the parts of the field where it will do the
best, instead of responding to average conditions. This increases yield and
decreases fertilizer use. Eventually, farmers may -incorporate long-term
weather forecasts into their planning as well, so that they can cut back on
fertilizer use when the weather is likely to make harvests poor anyway,
says Ron Olson, an agronomist with Cargill Fertilizer in Tampa, Florida.
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L
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Organic techniques certainly
have their benefits, especially for poor farmers. But strict “organic
agriculture”, which prohibits certain technologies and allows others, isn’t
always better for the environment. Take herbicides, for example. These can
leach into waterways and poison both wildlife and people. Just last month,
researchers led by Tyrone Hayes at the University of California at Berkeley
found that even low concentrations of atrazine, the most commonly used weed
killer in the US, can prevent frog tadpoles from developing properly.
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Questions 1 – 4
Use the information in the
passage to match the people (listed A-D) with opinions or deeds below.
Write the appropriate letters A-D in
boxes 1-4 on your answer sheet.
A
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Vaclav Smil
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B
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Bill
Liebhardt
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C
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Kenneth
Cassman
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D
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Ron Olson
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1
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Use of chemical fertilizer can be optimized by combining weather information.
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2
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Organic framing yield is nearly equal to traditional ones.
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3
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Better
agricultural setting is a significant key to solve environmental tough nut.
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4
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Substantial production loss would happen in case all farmers shifted
from using synthetic fertilizer.
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Questions 5 – 9
Do the following statements
agree with the information given in Reading Passage 1
In boxes 5-9 on your answer sheet,
write
YES
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if the statement agrees with the information
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NO
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if the statement contradicts the information
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NOT GIVEN
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if there
is no information on this
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5. Increasing population, draining irrigation, eroding farmland push
agricultural industry to extremity.
6. There are only two options for farmers; they use chemical
fertilizer or natural approach.
7. Chemical fertilizer currently is more expensive than natural
fertilizers.
8. In order to keep nutrients in the soil, organic farmers need to
rotate the planting method.
9. “organic agriculture” is the way that environment-damaging
technologies are all strictly forbidden.
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Questions
10-13
Complete
the following summary of the paragraphs of Reading Passage, using no more
than two words from the Reading Passage for each answer.
Write
your answers in boxes 10-13 on your answer sheet.
Several 10 …………………… approaches need to be applied in the order that
the global population wouldn’t go starved. A team called 11……………………
repeated the viewpoint of a scholar by a survey in British farming. More
and more European farmers believe in 12……………………farming these years. The
argument of organic against 13……………………seems in an inaccurate direction.
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