VOA标准英语2009年-UN Study Calls for More Debate on Biofuels

By Alisha Ryu
Nairobi
16 October 2009

 
UNEP's 'Assessing Biofuels' report cover 
A new report by the United Nations Environment Program says developing biofuels as a green energy option is beneficial only when countries adopt a sophisticated approach. The report has warnings for African countries, which are already struggling to cope with the loss of productive farmlands through drought and land degradation¹.

The study, conducted by UNEP's International Panel for Sustainable Resource Management, concludes that while biofuel production and use may appear to be a solution for cutting greenhouse gas emissions² caused by burning of fossil fuels, some biofuels are much more climate-friendly than others.

The report says biofuels can lead to reduced emissions or worsen the problem. For example, the study says using ethanol fuel made from sugar cane³, as practiced in some countries like Brazil, can lead to emissions reductions of up to 100 percent when substituted for fossil fuel. But making and using bio-diesel from palm oil on deforested land can lead to a significant increase in emissions when compared to using gasoline. 

Given that most biofuels today are made from food crops such as maize⁴, wheat, sugar cane, vegetable and palm oils, the authors of the study say it is also important that the growth of the biofuel industry does not encourage unsustainable habits, such as using productive farmlands to grow energy crops.

UNEP's spokesman Nick Nuttall says far more research and debate is needed to determine which energy crops can grow where and how best to use limited land resources to combat climate change. He says other considerations include the impact of energy crops on such things as local water quality, quantity and biodiversity.

"Too much of a good thing can become a problem and that has to do with the fact that there is only a certain amount of land available on our planet," said Nick Nuttall. "Water supplies and some of the impacts on soil fertility, N20 [carbon] emissions - these are factors that need to be assessed."

David Newman, who runs the Nairobi-based biofuels consultancy Endelevu Energy, research and debate are especially critical for Africa, where sustainable land management and agricultural production efforts are often at odds⁵ with the need for development.

One of the most controversial local issues is the production of bio-diesel, which Newman says could be a disaster for some African countries trying to enter the market.

"Bio-diesel is, of course, based on virtually any vegetable oil, feed stock, and there are edible⁶ feed stocks and there are inedible⁷ feed stocks," said David Newman. "And that is very relevant in a place like Kenya, which is a net-importing country when it comes to edible vegetable oil. So, it would be potentially dangerous to base a bio-diesel industry on large-scale production of those feed stocks because it would be in direct competition with the deficit⁸ demand for food."

This week, Kenya's neighbor, Tanzania, announced that it was halting further land allocations for biofuel development until a framework to regulate the industry is in place.

The government move follows reports that arable⁹ land that could be used to grow food is being increasingly used for biofuel production.

1 degradation   

n.降级；低落；退化；陵削；降解；衰变

参考例句：

• There are serious problems of land degradation in some arid zones.在一些干旱地带存在严重的土地退化问题。
• Gambling is always coupled with degradation.赌博总是与堕落相联系。

2 emissions   

排放物( emission的名词复数 )； 散发物（尤指气体）

参考例句：

• Most scientists accept that climate change is linked to carbon emissions. 大多数科学家都相信气候变化与排放的含碳气体有关。
• Dangerous emissions radiate from plutonium. 危险的辐射物从钚放散出来。

3 cane   

n.手杖，细长的茎，藤条；v.以杖击，以藤编制的

参考例句：

• This sugar cane is quite a sweet and juicy.这甘蔗既甜又多汁。
• English schoolmasters used to cane the boys as a punishment.英国小学老师过去常用教鞭打男学生作为惩罚。

4 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。

5 odds   

n.让步，机率，可能性，比率；胜败优劣之别

参考例句：

• The odds are 5 to 1 that she will win.她获胜的机会是五比一。
• Do you know the odds of winning the lottery once?你知道赢得一次彩票的几率多大吗？

6 edible   

n.食品，食物；adj.可食用的

参考例句：

• Edible wild herbs kept us from dying of starvation.我们靠着野菜才没被饿死。
• This kind of mushroom is edible,but that kind is not.这种蘑菇吃得，那种吃不得。

7 inedible   

adj.不能吃的，不宜食用的

参考例句：

• The food was totally inedible.食物完全无法下咽。
• These chemicals make the fruit inedible.这些化学品使这种水果不宜食用。

8 deficit   

n.亏空，亏损；赤字，逆差

参考例句：

• The directors have reported a deficit of 2.5 million dollars.董事们报告赤字为250万美元。
• We have a great deficit this year.我们今年有很大亏损。

9 arable   

adj.可耕的，适合种植的

参考例句：

• The terrain changed quickly from arable land to desert.那个地带很快就从耕地变成了沙漠。
• Do you know how much arable land has been desolated?你知道什么每年有多少土地荒漠化吗？