In polar and cold temperate regions many of the evergreens are shrubs or trees with needlelike or scalelike leaves, adaptations that prevent water loss by transpiration.

 
  • 在两极或寒温带,多数常绿植物是灌木或具针状、鳞状叶片的树,这是一种防止因蒸腾而散失水分的适应机制。
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