SORU: aşağıdaki parçaya göre cevaplayınız
According to the passage, the use of nitrogen fertilizers for agricultural purposes ----.
The hope with biofuels is that they can offer a carbonneutral
energy source, because the crops that are
grown for fuel will remove as much carbon from the
atmosphere as will be released when they are
eventually burned. This is basically the same thing that
happens when we burn coal or oil. The difference is
that in the case of the latter, the cabon was absorbed
hundreds of millions of years ago, and this is part of the
problem. Humans will take just a few hundred years to
burn through tens of millions of years of oil deposits.
To grow enough crops to keep up with our current
demand will require lots of additional lands to be
cleared for agriculture. If rainforests are cleared to
plant sugar cane, all the carbon that is currently locked
in the trees will be released. The other problem is that
adding nitrogen fertilizer to these crops releases
nitrogen oxide, which is another greenhouse gas.
A recent study showed that burning maize biofuels
actually increases greenhouse gas emissions for this
reason. However, this is more the fault of the choice of
biofuel crop and the production method rather than a
flaw in the biofuel concept as a whole. The shrub
“jatropha”, for instance, can be grown on land too poor
for trees or other crops to grow on, and is already used
for biodiesel in India, Cambodia, and some African
countries.