The stubble was burning in the fields.

残株在田地里燃烧着。

《柯林斯英汉双解大词典》

They are burning off the stubble in the fields.

他们正在烧掉地里的残茬。

《新英汉大辞典》

Experts say the rising food prices are partly due to climate change - and because fields once used to grow food crops are now used to cultivate crops for cleaner-burning biofuels.

专家们表示，粮价上涨的部分原因是气候的变化，另一个原因是过去被用来种庄稼的农田现在被用来种植生产洁净的生物燃料的作物。

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I've been able to get to within about 10 miles of Kirkuk -- able to see the oil capital of the north: a burning flare, a harmless flare, burning off gases from one of the major oil fields on the outskirts of Kirkuk.

CNN: Brent Sadler: Kurds say time is ripe

As well as destroying such native ecosystems, deforestation also diminishes so-called "carbon sinks" -- thereby reducing the Earth's capacity to absorb and re-process atmospheric carbon dioxide -- while also adding to air pollution through the burning of land to clear it for cultivation (sugarcane fields are traditionally fired prior to harvest to remove leaves and drive away snakes).

CNN: Biofuel: Green savior or red herring?

It recommends they use rice and wheat straw for mulch instead of burning it, rotate their crops, use a range of different seeds, manure their fields, and so on.

ECONOMIST: Punjabis are poisoning themselves