VOA标准英语2010年-Farming with Less Fossil Fuel Won't Me

Researchers get same yields with fewer fertilizers, pesticides²

Steve Baragona | Washington, DC 18 May 2010 
 Fossil energy use was compared among different crop rotation³ systems in a field experiment conducted between 2003 and 2008 in Boone Co., Iowa

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Read the study abstract in the Agronomy⁴ Journal

As rising petroleum⁵ prices continue to increase the costs of producing food, new research suggests farmers can use less fossil fuel without reducing their crop yields or profits.

Modern commercial farming consumes a lot of fossil fuel. Gasoline powers farm equipment. Natural gas is a key ingredient in the synthetic⁶ fertilizers that replenish⁷ the nutrients⁸ in the soil. And commonly used chemical pest-killers are petroleum-based.

These techniques have produced remarkable⁹ productivity gains and record harvests. But oil prices have been rising all decade, and experts predict they will continue to do so.

Cheap energy

"I think many farmers recognize that what we do now derives¹⁰ in a large part from relatively¹¹ inexpensive energy," says Iowa State University agronomy professor Matt Liebman. "And if that system changes, then we may have to re-evaluate what's the best system for our land and our climate."

The typical commercial farm in the United States alternates between growing maize¹² one year and soybeans the next. Liebman and his colleagues have been experimenting with alternatives.

Rather than a 2-year, maize-soybean rotation, they grew a 4-year rotation that included two other commercially valuable crops: oats and alfalfa. Since these crops are grown and harvested differently than corn and soybeans, they help disrupt the lifecycle of crop weeds. That meant the reserachers could use less weed-killer.

Alfalfa also helps return nutrients to the soil, which reduced the need for fertilizer. And when they did fertilize¹, Liebman's group used livestock¹³ manure¹⁴ rather than synthetics¹⁵.

Same yields, less fossil fuels

Using these techniques, Liebman says, "We were able to reduce our use of fertilizers, pesticides and fossil fuels a lot, without reducing crop production."

In a study in the Agronomy Journal, Liebman's group produced as much or more maize and soybeans as conventional fields, but used a quarter to a half as much fossil fuel. Furthermore, farmers who followed this system would earn about as much money as their conventional counterparts.

Orvin Bontrager, a veteran farming adviser¹⁶ with the company Servi-Tech, gave the study mixed reviews.

"I don't doubt the savings¹⁷ he's seeing here on the energy," he says. "My question — several questions, I guess — would be from the labor¹⁸ side."

Bontrager says if most farms switched to Liebman's system, there might not be enough labor available to handle the additional crops. Plus, farmers would have to buy new equipment to harvest them. And there may not be a market for such a big increase in alfalfa.

'It comes down to economics'

But, Bontrager says, that doesn't mean farmers won't change their methods.

"It comes down to economics," he says. "If the price of oil does get that high, [then] fertilizer and chemicals obviously get a lot higher. And if the prices of crops do not follow along, then obviously we will be going to something like this because it just makes economic sense to do that."

Bontrager adds that when oil prices peaked in 2008, and fertilizer prices spiked¹⁹ along with them, manure became a lot more attractive. He says that shows farmers are willing to make the changes — if the price is right.
 

1 fertilize   

v.使受精，施肥于，使肥沃

参考例句：

• Fertilizer is a substance put on land to fertilize it.肥料是施在地里使之肥沃的物质。
• Reading will fertilize his vocabulary.阅读会丰富他的词汇。

2 pesticides   

n.杀虫剂( pesticide的名词复数 )；除害药物

参考例句：

• vegetables grown without the use of pesticides 未用杀虫剂种植的蔬菜
• There is a lot of concern over the amount of herbicides and pesticides used in farming. 人们对农业上灭草剂和杀虫剂的用量非常担忧。 来自《简明英汉词典》

3 rotation   

n.旋转；循环，轮流

参考例句：

• Crop rotation helps prevent soil erosion.农作物轮作有助于防止水土流失。
• The workers in this workshop do day and night shifts in weekly rotation.这个车间的工人上白班和上夜班每周轮换一次。

4 agronomy   

n.农业经济学

参考例句：

• The science of agronomy helps farmers obtain larger and better crops.农业经济学帮助农民获得更多更好的农作物。
• Heavy agronomy clique and Si Mi order of believe in nature.重农学派和斯密都信奉自然秩序。

5 petroleum   

n.原油，石油

参考例句：

• The Government of Iran advanced the price of petroleum last week.上星期伊朗政府提高了石油价格。
• The purpose of oil refinery is to refine crude petroleum.炼油厂的主要工作是提炼原油。

6 synthetic   

adj.合成的，人工的；综合的；n.人工制品

参考例句：

• We felt the salesman's synthetic friendliness.我们感觉到那位销售员的虚情假意。
• It's a synthetic diamond.这是人造钻石。

7 replenish   

vt.补充；(把…)装满；(再)填满

参考例句：

• I always replenish my food supply before it is depleted.我总是在我的食物吃完之前加以补充。
• We have to import an extra 4 million tons of wheat to replenish our reserves.我们不得不额外进口四百万吨小麦以补充我们的储备。

8 nutrients   

n.（食品或化学品）营养物，营养品( nutrient的名词复数 )

参考例句：

• a lack of essential nutrients 基本营养的缺乏
• Nutrients are absorbed into the bloodstream. 营养素被吸收进血液。 来自《简明英汉词典》

9 remarkable   

adj.显著的，异常的，非凡的，值得注意的

参考例句：

• She has made remarkable headway in her writing skills.她在写作技巧方面有了长足进步。
• These cars are remarkable for the quietness of their engines.这些汽车因发动机没有噪音而不同凡响。

10 derives   

v.得到( derive的第三人称单数 )；（从…中）得到获得；源于；（从…中）提取

参考例句：

• English derives in the main from the common Germanic stock. 英语主要源于日耳曼语系。 来自《简明英汉词典》
• He derives his income from freelance work. 他以自由职业获取收入。 来自《简明英汉词典》

11 relatively   

adv.比较...地，相对地

参考例句：

• The rabbit is a relatively recent introduction in Australia.兔子是相对较新引入澳大利亚的物种。
• The operation was relatively painless.手术相对来说不痛。

12 maize   

n.玉米

参考例句：

• There's a field planted with maize behind the house.房子后面有一块玉米地。
• We can grow sorghum or maize on this plot.这块地可以种高粱或玉米。

13 livestock   

n.家畜，牲畜

参考例句：

• Both men and livestock are flourishing.人畜两旺。
• The heavy rains and flooding killed scores of livestock.暴雨和大水淹死了许多牲口。

14 manure   

n.粪，肥，肥粒；vt.施肥

参考例句：

• The farmers were distributing manure over the field.农民们正在田间施肥。
• The farmers used manure to keep up the fertility of their land.农夫们用粪保持其土质的肥沃。

15 synthetics   

n.化学合成物

参考例句：

• cotton fabrics and synthetics 棉织物与合成织物
• It is a universally applicable thickener for printing on the synthetics. 特别适合用做纺织印染工业中人造合成纤维的印染增稠剂。

16 adviser   

n.劝告者，顾问

参考例句：

• They employed me as an adviser.他们聘请我当顾问。
• Our department has engaged a foreign teacher as phonetic adviser.我们系已经聘请了一位外籍老师作为语音顾问。

17 savings   

n.存款，储蓄

参考例句：

• I can't afford the vacation,for it would eat up my savings.我度不起假，那样会把我的积蓄用光的。
• By this time he had used up all his savings.到这时，他的存款已全部用完。

18 labor   

n.劳动，努力，工作，劳工；分娩；vi.劳动，努力，苦干；vt.详细分析；麻烦

参考例句：

• We are never late in satisfying him for his labor.我们从不延误付给他劳动报酬。
• He was completely spent after two weeks of hard labor.艰苦劳动两周后，他已经疲惫不堪了。

19 spiked   

adj.有穗的；成锥形的；有尖顶的

参考例句：

• The editor spiked the story. 编辑删去了这篇报道。 来自《简明英汉词典》
• They wondered whether their drinks had been spiked. 他们有些疑惑自己的饮料里是否被偷偷搀了烈性酒。 来自辞典例句