抑制全球變暖有奇招：讓牛羊放“袋鼠屁”

Australian scientists are trying to give kangaroo-style stomachs to cattle and sheep in a bid to cut the emission of greenhouse gases blamed for global warming.

Thanks to special bacteria in their stomachs, kangaroo flatulence contains no methane and scientists want to transfer that bacteria to cattle and sheep who emit large quantities of the harmful gas.

While the usual image of greenhouse gas pollution is a billowing smokestack pushing out carbon dioxide, livestock passing wind contribute a surprisingly high percentage of total emissions in some countries.

“Fourteen percent of emissions from all sources in Australia is from enteric methane from cattle and sheep,” said Athol Klieve, a senior research scientist with the Queensland state government.

“And if you look at another country such as New Zealand, which has got a much higher agricultural base, theyre actually up around 50 percent,” he said.

Researchers say the bacteria also makes the digestive process much more efficient and could potentially save millions of dollars in feed costs for farmers.

But it will take researchers at least three years to isolate the bacteria, before they can even start to develop a way of transferring it to cattle and sheep.

Another group of scientists, meanwhile, has suggested Australians should farm fewer cattle and sheep and just eat more kangaroos.

The idea is controversial, but about 20 percent of health conscious Australians are believed to eat the national symbol already.

“Its low in fat, its got high protein levels and its very clean in the sense that basically its the ultimate free range animal,” said Peter Ampt of the University of New South Waless institute of environmental studies.

為了減少導(dǎo)致全球變暖的溫室氣體的排放，澳大利亞科學(xué)家目前正在想辦法將牛羊胃變成袋鼠式的胃。

袋鼠胃中有一種特殊的細(xì)菌能使其放的屁中不含有甲烷。科學(xué)家想將這種細(xì)菌移至牛羊的胃中，以抑制它們所排放的大量有害氣體。

說到二氧化碳等溫室氣體的排放，人們腦中通常會(huì)出現(xiàn)一個(gè)大煙囪冒出滾滾濃煙的畫面。但在一些國家，牲畜放的屁在溫室氣體排放總量中所占的比例十分驚人。

昆士蘭州政府的高級(jí)科研人員阿索爾·克里弗說：“在澳大利亞，牛羊排放的甲烷占溫室氣體排放總量的14%。”

“而在農(nóng)業(yè)更為發(fā)達(dá)的新西蘭，這一比例則高達(dá)50%。”

研究人員稱，袋鼠胃中所含的那種細(xì)菌還可以促進(jìn)消化，從而能為農(nóng)民節(jié)省幾百萬美元的飼料成本。

但科學(xué)家至少得用三年的時(shí)間分離出這種細(xì)菌，然后還得設(shè)法將其移至牛羊的胃中。

此外，另一組科學(xué)家建議澳大利亞人應(yīng)少養(yǎng)牛羊，多吃袋鼠肉。

盡管這一觀點(diǎn)有爭(zhēng)議，但目前約有20%健康意識(shí)較強(qiáng)的澳大利亞人已經(jīng)吃上了被視為“國家象征”的袋鼠。

新南威爾士大學(xué)環(huán)境研究所的彼特·阿姆普特說：“袋鼠肉富含蛋白質(zhì)，脂肪含量低。而且由于袋鼠是散養(yǎng)動(dòng)物，所以它的肉很干凈。”