每日跟讀#711: A Race Against the Sun

It was a long, hot summer, like most in the San Joaquin Valley. The pistachio trees planted in orderly rows — and the growers who nurture them — are accustomed to harsh conditions. With their deep roots and tough, gnarly branches, pistachio trees are hardy, tolerant of salty soils and brutal heat waves. Some can live for centuries.

美國加州聖華金谷這個夏天又熱又長，跟以往大多時候一樣。成排種植的開心果樹和果農都已習慣嚴苛的環境。開心果樹根札得深，枝幹粗壯扭曲，耐得住寒冷、含鹽土壤和逼人的熱浪。有的能活好幾個世紀。

But while sweltering summers are the norm in this part of central California, there’s a new, existential threat to these trees, one that scientists warn could spell the end of the pistachio harvest: warmer winters. Many crops are facing similar threats as agricultural regions across the world experience previously unseen extremes in heat, rain and drought.

雖然加州中部這塊地方夏天本就悶熱，這些果樹卻面臨一種新的生存威脅，科學家警告說，這種威脅可能意味再也沒有開心果可以收成，那就是冬天變暖。世界各地農業區正經歷前所未見的熱浪、暴雨及乾旱，許多其他作物面臨類似危機。

Chilly winters are critical to nut and fruit trees, particularly pistachios. To break their slumber and spread their pollen, pistachios need to spend about 850 hours, or five weeks, at temperatures below 45 degrees.

寒冷的冬天對堅果和水果樹十分重要，尤其是開心果。為了打破休眠狀態並散播花粉，開心果必須有850小時，亦即五周左右，處在華氏45度（攝氏7.2度）以下。

So as the San Joaquin Valley warms and its cooling fogs retreat, growers have found their orchards out of sync: Many male trees are no longer producing pollen when the females need it.

所以當聖華金谷逐步回暖，冷霧消退時，農民發現果園出了狀況：雌樹需要雄樹授粉時，許多雄樹卻不再產生花粉。

After suffering a billion-dollar loss from a recent warm winter, California pistachio growers don’t need much convincing that their livelihoods are endangered by climate change. Heeding warnings that the industry may not survive past the middle of the century, they are among the world’s earliest adapters. Scientists are wrangling and crossing genes to breed trees that can survive a warmer world, and growers are hedging their bets by planting experimental trees that need fewer chilly days.

加州開心果農因為最近一次暖冬而損失十億美元後，無需勸說也明白生計受到氣候變遷威脅。他們把這個產業可能撐不到本世紀下半的警告聽了進去，成為世上最早開始調整的群體之一。科學家把植物聚合在一起並使之雜交，以培育更能適應高溫的樹種，果農也同時種植需要寒冷天數較少的實驗樹種，藉以避險。

“There’s a lot to be said about traditional knowledge. But this is new territory,” said Rebecca Carter of the World Resources Institute, a nonprofit research group that is working with growers around the world to adapt to the threats of climate change, including warmer winters, dried-up aquifers and record-breaking heat waves.

非營利組織世界資源研究所的麗貝卡．卡特說：「傳統知識有很多好處，不過這是新領域。」這個研究所與世界各地農民合作，幫助他們應對氣候變遷的威脅，包括冬天變暖、地下蓄水層枯竭與熱浪空前。

Scientists in 2013 urged “immediate adaptation” by farmers to ensure that they can feed the 10 billion people expected to inhabit the planet by 2050. They warned in a study that world hunger would worsen as crop yields declined, pests and diseases increased, water demand skyrocketed and highly vulnerable crops vanished. “The whole food system needs to change,” according to the report published in the journal Science.

科學家2013年就呼籲農民「立刻調整作法」，以確保料將在2050年前達到100億的地球人口都有得吃。他們在「科學」期刊上發表一篇研究報告示警說，隨著作物產量減少、病蟲害增加、水資源需求高漲和高度脆弱的作物消失，全球飢餓問題將惡化，「整個食物系統都得改變」。

Coping, Carter said, would “require fundamental changes in how food is produced, how land is used, who lives where and what economic activities occur in specific areas.”

卡特說，處理這個問題「必須在食物生產、土地利用、居住範圍和特定區域的經濟活動等方面徹底改變」。

Those changes are already happening worldwide. After growing coffee for generations, farmers in parts of Costa Rica are switching to oranges. Kenyan herders, facing intense droughts, are raising camels instead of cattle. In China’s drought-prone Fujian province, farmers who grew wheat and corn have switched to apples.

這些改變已在全球各地發生。哥斯大黎加部分地區的農民在種植咖啡幾個世代後，改種柑橘。肯亞的牧人面對嚴重乾旱，從養牛改為養駱駝。在中國大陸容易發生乾旱的福建省，原本種小麥和玉米的農民改種蘋果。

Source article: https://paper.udn.com/udnpaper/POH0067/345636/web/#2L-15722568L