Land Use A problem related to the competition for land use is whether crops should be used to produce food or fuel. 【1】_____

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问题                          Land Use
    A problem related to the competition for land use
is whether crops should be used to produce food or fuel.
【1】______ will be examined in this respect.                          【1】______
Firstly, the problem should be viewed in its【2】______                【2】______
perspective. When oil prices rose sharply in the 1970s,
countries had to look for alternatives to solve the
resulting crisis.
In developing countries, one of the possible answers
to it is to produce alcohol from【3】______                            【3】______
This has led to a lot of research in this area, particularly
in the use of【4】______ . The use of this material resulted           【4】______
from two economic reasons: a【5】______ in its price and               【5】______
low【6】______ costs.                                                  【6】______
There are other starchy plants that can be used to produce
alcohol, like the【7】______ or the cassava plant                      【7】______
in tropical regions, and【8】______ and sugar beet in                  【8】______
non-tropical regions. The problem with these plants is
that they are also the people’s staple food in many poor countries.
Therefore, farmers there are faced with a choice:
crops for food or for fuel. And farmers naturally go
for what is more【9】______ . As a result, the problems                【9】______
involved are economic in nature, rather than technological.
This is my second area under consideration. Finally, there
have already been practical applications of using
alcohol for fuel. Basically, they come in two forms of use:
pure alcohol as is the case in【10】______ , and a combination        【10】______
of alcohol and gasoline known as gasohol in Germany.
【4】
Today I’m going to consider very briefly a problem concerned with the competition for land use. That is, that is, whether crops should be used to produce food, or to, should be used to produce fuel. And um in considering this problem I will look at three main areas. The historical background to the problem, the nature of the problems involved in, in the competition for land use, and some examples.
   In considering the historical background, urn, we should look at the oil crisis of the 1970s. Um due to the rapidly increase in, in, or the rapid, due to the rapid trend in increasing oil prices leading to an energy crisis, many countries have looked for alternative, er, energy sources to make them independent of other countries’ fossil fuels. Examples of alternate, alternative energy sources include such things as solar power, the harnessing of wind, and wi, the wind and waves, tides, and also the production of biogas. Biogas is methane which is produced from human and animal waste.
   A particularly interesting possibility for many developing countries has been the conversion of plant material to alcohol. This, this is interesting because in many developing countries there is a large agricultural sector, and at the same time a small industrial sector, and thus the, the possibility of using the agricultural sector to, to produce fuel, um, is of interest to those countries.
   Scientific research is going on in the production of alcohol, for example, from sugar. And there are two, urn, two economic reasons for this. First of all the world price of sugar has fallen dramatically, or the world price of sugar has fallen in very real terms in the last decade, which, this has caused a problem for those economies which are dependent on their sugar production as it gives them an alternative, er, possibility for using their sugar. And secondly, sugar is the most efficient source of alcohol. Therefore it is relatively economical to make fuel by distilling alcohol from it.
   In addition to sugar there are other starchy plants that can be used to make alcohol. For example in tropical countries, such plants as the cassava plant and the sweet potato are good sources from which alcohol can be made, and in, in non-tropical countries you have such things as corn and sugar beet.
   Now there is a problem arising from the fact that alcohol ~an be distilled from starchy plants, and that is, that many poor countries use precisely these starchy plants, or these starch-rich crops, er, for their food as a staple diet. So in, in many such countries there’s, there’s a conflict if you like, between the choice of whether to produce these crops for fuel, or to to produce these crops, er, for, for food and for their use as their staple diet.
   It is in fact an economic problem rather than a technical problem as the poor farmers will tend to choose that which is most profitable. Indeed it is an economic problem, not, not necessarily a technological problem. The technology for the conversion of alcohol from starchy plants has been in existence for over 40 years. And there are two ways of um using alcohol as car fuel. One such way, urn, is in the form of pure alcohol. An example of this is in Brazil in a project called the Pro-Alcool Project, and in Brazil cars are being produced to run on pure alcohol. A second use of alcohol as a car fuel is in a mixture with petrol, or with gasoline. In a mixture with gasoline this produces a mixture called "gasohol". In Germany for example, they have an experiment in which there, there’s such a mixture of 85 per cent petrol, or 85 per cent gas, 85 per cent gasoline and 15 per cent methanol.
   So if technology and the conversion of engines are not a problem, then really it is a question of economics, and there are three main factors which would affect the production...

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答案sugar

解析 紧接上题。农作物变燃料的第一个研究对象是糖类。
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