迄今调查活立木年龄的方法,都是采取砍伐或在树干上钻孔取样。这样做势必破坏树木或影响其健康生长。不久前日本东京大学试验成功一种X射线装置,用它围卡住树干,可得到树干内断层面的图象,从而读出该树的年轮。 So far the method of investigating the age of standing trees has been to cut or drill holes in the trunk. This will destroy the trees or affect their healthy growth. Not long ago, at Tokyo University, Japan, an X-ray device was successfully tested. Using it to capture the trunk, an image of the fault surface in the trunk was obtained and the tree ring was read out.