upper ten cm of the taproot

例句：

1. 1.The plant's main root is 2 meters long.
   这株植物的主根有2米长。
2. 2. The tree's upper part of the taproot is rotting away.
   这棵树的主根上部正在腐烂。
3. 3.The scientist studied the upper ten cm of the taproot to understand its growth patterns.
   这位科学家研究了主根上部的10厘米，以了解其生长模式。