(单词翻译:单击)
The world will need to double food production within the next three decades
在未来的三十年里，全球粮食的产量将需增加一倍，
in order to feed a rapidly growing and increasingly affluent population,
才足以养活快速增长并且日益富足的人口。
which is projected to grow from 7 billion today to 9 billion.
预计三十年内世界人口将从现在的70亿增长至90亿。
A United Nation report says reaching that goal will require major increases in intensive,
一份联合国的报告显示，要实现这一目标，就需要加强畜牧业的集约化，
high-efficiency livestock operations for both meat and dairy production.
无论是在肉类制品还是乳制品的生产方面。
The report also says that intensive livestock operations can pose serious ecological risks.
报告还显示，集约化的畜牧业生产会导致严重的生态风险。
And that's why environmental critics are calling instead for reductions in global livestock production,
这就是一些环保主义者呼吁减少畜牧业产品产量，
and urging people to consume less, not more, meat in their diets.
并要求人们减少而非增加对肉类的消费的原因。
Feeding today's population is a challenge for an already-stressed environment.
养活现存的人口对已经资源紧张的环境来说是一个挑战。
The challenge is how to ensure food without increasing animal numbers and having an impact on fragile lands and our resource bases.
这个挑战就是如何在不增加牲畜数量、不对脆弱的土地和我们的资源基数造成影响的基础之上保证人口食物的来源。
More than half of the agricultural land in the world is used to raise and feed livestock.
世界上有一半的可耕种土地被用来喂养牲畜。
Those farm animals are also responsible for 18 percent of the greenhouse gases released into the atmosphere every year.
另外，每年释放到大气中的温室气体中有18%是这些生活在农场的牲畜制造出来的。
Experts agree that the next few decades will present a puzzle,
专家们同意这种说法：人类在将来的几十年中会遇到一个难题——
how to feed nine billion people without wrecking the planet in the process.
如何在不毁坏地球的前提下养活90亿人口。
