Most shoppers know the feeling. You stand in front of piles of organic produ

游客2023-09-05  15

问题     Most shoppers know the feeling. You stand in front of piles of organic produce and wonder what those premium prices are buying you over and above what you get from standard foods. Not a lot nutrition-wise, it seems. Organic farming may not even be more sustainable. But could the whole debate about organic versus non-organic be missing the point?
    Understanding nutrition is, of course, vital when it comes to choosing food. In a report published recently, a team from the London School of Hygiene & Tropical Medicine examined 162 papers that compared organic and conventionally produced food. They concluded that there was no evidence to back up claims that organic food is more nutritious.
    But this is only one of the aspects of organic food that shoppers care about, and things get even more complicated when other, factors are brought into the equation. Many buy organic fruit and vegetables because they are not sprayed with pesticides. We know these can cause birth defects, cancer, and even the diabetes epidemic but it remains unclear whether the amounts in conventionally grown fruit and vegetables are high enough to be a health hazard.
    And then there are issues unrelated to health. Take energy use. True, some organic farming systems are more energy-efficient, partly because they do not use synthetic fertilizers, which are energy-intensive to produce. However, there is limited pressure on organic farmers to cut emissions. They don’t yet have to do so to qualify for organic status. As Laurie Drinkwater, an expert in sustainable agriculture at Cornell University in New York, points out, "Organic agriculture is not without environmental consequences." Indeed, according to Jules Pretty, an agricultural scientist at the University of Essex in Colchester, some organic farms keep weeds down with propane burners (丙烷加热器), which produce carbon dioxide.
    Soil erosion is another confounding factor. Many organic farms emphasize crop rotation, in part to ensure that fields are not left uncovered and vulnerable to erosion. The trouble is some organic farmers actually cause erosion by tilling the soil frequently to tackle the weeds.
    It’s not about whether organic food is good or a sham. That’s the wrong question. We should be asking how we can make all of agriculture more sustainable. Rather than compare organic and conventional systems in a simplistic way, Drinkwater and Pretty say we should identify the things we want from farms and then design a farming system — organic or otherwise — that best meets those goals.
    Producing enough food is an obvious aim, but farmers can also help boost biodiversity, keep rivers free of certain kinds of pollution, and fight climate change. There is also the question of animal welfare. You would probably end up with a system that borrows techniques from many existing farming methods. That would be good news for farmers and the rest of society, even though it might not produce so many snappy headlines. [br] According to experts, organic farms are not completely environmentally friendly because some of them______.

选项 A、use energy-intensively produced synthetic fertilizers
B、produce carbon dioxide while removing weeds
C、use high doses of weed-killer
D、use too many resources to qualify for organic status

答案 B

解析 第四段末句提到,据英国埃塞克斯大学农学家Jules Pretty说,部分有机农场采用能产生二氧化碳的丙烷加热器除草。由此看出,部分有机农场在除草时会产生二氧化碳,[B]中的removing weeds是对短文中keep weeds down的同义转述,故答案为[B]。
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