题目内容
5.Organic farming is a big-picture exercise.It's not only targeted at this season's results,but considers future generations.In the long run it makes better economic sense as well.But its main goal is to contribute to a healthier world.Studies conducted all over the world have shown the effects that conventional chemical farming has on the environment.Certainly,chemical fertilizers,pesticides,and herbicides increase the quantity of a farm's production.They help produce more grains and vegetables.But at what cost?A Swiss study showed that organic farming produces an average of 20% less than conventional methods.But the organically grown food contained 50% less fertilizer and 97% less pesticides.
Though only a part of the amount of pesticides a farm uses actually does the job of killing bugs,all of it remains active in the soil for months or even years after application.Perhaps worse,each generation of pests is growing increasingly immune (免疫的)to the chemicals used.It's not even all about the food and the soil.The pesticides used in conventional agriculture are finally spilling their chemical residues(化学残留) into the waterways.It affects wildlife,soil and ecosystems as a whole.According to a Worldwatch paper,Deep Trouble:The Hidden Threat of Groundwater Pollution,poisonous chemicals are polluting groundwater on every inhabited continent,endangering the world's most valuable supplies of freshwater.
Perhaps not so intuitive,organic farming affects the air."Organic agriculture can reduce greenhouse gas emissions by effectively locking more carbon into the soil rather than releasing it into the atmosphere,"found"Farming Systems Trial,"a 15-year study.Organic agriculture even uses 50% less energy than conventional farming.
How does organic farming deal with pests?Organic farmers intentionally build up populations of beneficial insects,such as ladybugs,that eat other pests and control the growth of insects.Wildflowers create green belts that control the spread of weeds and themselves encourage the beneficial insects.
Farmers have to stick to strict standards and practices to earn the label"organic."Looking forward,by promoting biological diversity and maintaining soil fertility,organic farming creates a natural balance that helps to get high quality food in healthy quantities year after year.
33.Which of the following can be the best title for the passage?B
A.The best ways to set up organic farming
B.Why organic farming benefits the environment
C.The history and development of organic farming
D.How to deal with pests and chemical residues
34.It can be known from the passage thatD.
A.applying pesticides will increase the number of pests
B.organic farming produces more greenhouse gas emissions
C.conventional farming is better than organic farming
D.the organically grown food does good to people's health
35.By writing Paragraph 3,the author mainly wants to tell usC.
A.the immune function of pests
B.the effect of chemical residues
C.the great harm of pesticides
D.the benefit of conventional agriculture.
分析 本文通过几个方面说明有机农业为什么会对环境有好处.
解答 33.B主旨大意题.本文通过几个方面说明有机农业为什么会对环境有好处.文章第一段为主题段,下面各段都是围绕这一主题段进行说明的.
34.D推理判断题.根据第二段最后一句But the organically grown food contained 50% less fertilizer and 97% less pesticides.可知,有机农产品含有的肥料少,含有的农药更少,由此可以推断,这种有机农产品对人的身体有益.
35.C 作者意图猜测题.文章第三段说明应用农药不仅会使害虫产生免疫,而且还会污染水源,影响野生动物、土壤和生态系统.这一切都是应用农药所产生的巨大危害.故选C.
点评 做阅读时经常犯错的主要原因是,仅凭读过文章后残留在脑海中的一丝印象来勾选答案,这样便很容易掉入出题人故意设布下的题目陷阱.所谓阅读理解,对于题目的理解一定要忠实于原文,因此,每一道题都应该与原文作全面的对比与核查,再得出答案.也就是说,阅读理解的每一道题目,在原文都应该有明确的出处,我们把这一出处叫做原文相关句,(1)排除与原文相关句主题不一致的选项(2)排除与原文相关句态度相反的选项 (3)排除用于过于极端或负面的选项(4)注意结合文章主旨和主题去排除.
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