Swedish researchers find world's oldest living tree

      The world's oldest living tree on record is a nearly 10,000 year-old spruce that has been discovered in central Sweden, Umeaa University said on Thursday.

      Researchers had discovered a spruce with genetic material dating back 9,550 years in the Fulu mountain in Dalarna, according to Leif Kullmann, a professor of Physical Geography at the university in northwestern Sweden.

      That would mean it had taken root in roughly the year 7,542 BC.

      "It was a big surprise because we thought until (now) that this kind of spruce grew much later in those regions," he said.

      Scientists had previously believed the world's oldest trees were 4,000 to 5,000 year-old pine trees found in North America.

      The new record-breaking tree was discovered in Dalarna in 2004 when Swedish researchers were carrying out a census of tree species in the region, Kullman said.

      The tree's genetic material age had been calculated using carbon dating at a laboratory in Miami, Florida.

      Spruces, which according to Kullmann offer rich insight into climate change, had long been regarded as relatively newcomers in the Swedish mountain region.

      The discovery of the ancient tree had therefore led to "a big change in our way of thinking," he said.

      位于瑞典西北部的优密欧大学于上周四公布，（研究人员）在瑞典中部发现了一棵有近万年树龄的云杉，据考证这棵云杉是目前世界上现存的最古老的树。

      该大学的自然地理学教授雷夫•卡尔曼说，研究人员在位于瑞典达拉那的浮露山上发现了一棵携带有9550年前遗传物质的云杉。

      由此推算，这棵树是在约公元前7542年开始生根的。

      卡尔曼教授说：“这个发现让我们很意外，因为我们一直认为这种云杉是在很多年后才开始在这一带生长的。”

      此前，科学家们一直认为目前世界上最古老的树是在北美发现的松树，这些树已有四五千年历史。

      卡尔曼说，这棵“打破纪录”的树是2004年瑞典研究人员在达拉那一带进行树种调查时发现的。

      美国佛罗里达州迈阿密的一个实验室采用碳测年法计算出了它的树龄。

      据卡尔曼介绍，云杉这种植物对气候变化十分敏感，而且长期以来一直被视为瑞典山区的“外来树种”。

      而这颗古树的发现“大大改变了我们的看法”。

      Vocabulary: 

      carbon dating：a chemical analysis used to determine the age of organic materials based on their content of the radioisotope carbon-14; believed to be reliable up to 40,000 years（碳测年）