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巧克力或于2050年消失殆盡

2019-08-30 08:56:13
時代英語·高二 2019年4期

Chocolate could soon be a thing of the past, after scientists warned that the cacao plant, from which chocolate is made, could be extinct within 31 years.

Over half of the worlds chocolate comes from just two countries in West Africa—C?te dIvoire and Ghana—where the temperature, rain, and humidity provide the perfect conditions for cacao to thrive.

But the threat of rising temperatures over the next three decades caused by climate change, is expected to result in a loss of moisture from the ground, which scientists say could upset this delicate balance.

According to the US National Oceanic and Atmospheric Administration, a temperature rise of just 2.1 degrees centigrade could spell an end for the chocolate industry worldwide by 2050.

Farmers in the region are already looking at moving cacao production areas thousands of feet uphill into mountainous terrain—much of which is currently preserved for wildlife.

But a move of this scale could destroy ecosystems that are already under threat from illegal farming and deforestation.

Part of the problem, according to Doug Hawkins from London-based research firm Hardman Agribusiness, is that cacao farming methods have not changed for hundreds of years.

“Unlike other tree crops that have benefited from the development of modern, high yielding cultivars and crop management techniques to realise their genetic potential, more than 90% of the global cocoa crop is produced by mallholders on subsistence farms with unimproved planting material,” he told Mail Online.

“All the indicators are that we could be looking at a chocolate deficit of 100,000 tonnes a year in the next few years.”

Now scientists at the University of California at Berkeley have teamed up with American confectionery company Mars, in an attempt to keep chocolate on the menu.

Using the controversial gene-editing technology known as CRISPR they are trying to develop a version of the cacao plant capable of surviving—and thriving—in dryer, warmer climates.

CRISPR has received widespread media attention because of its potential to eradicate human diseases and make so-called “designer babies”.

However, Jennifer Doudna, the UC Berkeley geneticist who invented CRISPR, thinks its most useful effects will be on plants rather than humans.

“Personally, Id love a tomato plant with fruit that stayed on the vine longer,” Doudna, who is an avid gardener, told Business Insider.

If the teams work on the cacao plant is successful, it could remove the need for farmers in West Africa to relocate to higher ground, and perhaps even allow cacao to be grown elsewhere in the world.

科學家發出了警告,制作巧克力所用的可可樹或將在31年內滅絕,真是這樣的話,巧克力很快就會成為歷史了。

僅科特迪瓦和加納這兩個西非國家,就提供了世界上超過半數的巧克力,因為兩地的溫度、降水及濕度為可可樹創造了絕佳的生長環境。

但由于氣候變化,氣溫在未來30年將持續升高,這會導致土壤水分流失——科學家認為,環境中微妙的平衡關系將因此被打破。

美國國家海洋與大氣管理局的研究表明,對全球的巧克力行業而言,氣溫僅上升2.1攝氏度就可能意味著2050年的滅頂之災。

當地農民已開始考慮將可可產區上遷至數千英尺的山區,那里現今多為野生動植物保護區。

但如此大舉搬遷可能會破壞本已受到非法耕作與亂砍濫伐威脅的生態系統。

在道格·霍金斯看來,這個問題在某種程度上要歸因于數百年來一成不變的可可種植方式。道格·霍金斯供職于倫敦一家名為“哈德曼農商企業”的調查公司。

他對英國《每日郵報》說:“其他木本作物得益于現代高產栽培和作物管理技術的發展,作物基因潛能得到充分發揮。與它們不同,全球超過90%的可可作物是由自足型農場的小農戶用未經改良的種子種植生產的。”

“所有跡象都表明,今后若干年,我們可能面臨每年10 萬噸的巧克力缺口。”

目前,加利福尼亞大學伯克利分校的科學家已與美國瑪氏糖果公司組成科研團隊,旨在讓巧克力繼續留在美食單上。

他們利用備受爭議的基因編輯技術,即眾所周知的CRISPR,試圖研發一種能在更加干燥和溫暖的氣候條件下存活并生長的可可植物。

CRISPR 目前得到媒體的廣泛關注,因為該項技術有望根除人類疾病,并培育出所謂的“定制嬰兒”。

然而,加州大學伯克利分校的遺傳學家、CRISPR的發明者珍妮弗·杜德娜認為,此項技術最大的用武之地在于植物而非人類。

酷愛園藝的杜德娜對美國《商業內參》表示:“我個人覺得,如果能培育出藤上掛果時間長一些的番茄樹,會更有意義。”

如果該團隊在可可作物的研發項目上能取得成功,西非的農民就無須將作物遷往更高的地帶,而且,可可樹或許還可以種植在世界其他地方了。

Word Study

extinct /?k'st??kt/ adj. 不再存在的;已滅絕的;絕種的

thrive /θra?v/ v. 蓬勃發展;旺盛;茁壯成長

spell /spel/ v. 招致,意味著(通常指壞事)

The crop failure spelt disaster for many farmers.

scale /ske?l/ n. 規模,范圍,程度

deficit /'def?s?t/ n. 不足額;缺少

gene-editing technology 基因編輯技術,指人類對目標基因進行“編輯”,實現對特定DNA片段的修改等。

eradicate /?'r?d?ke?t/ v. 根除;消滅;杜絕

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