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How Do Cacti Store Water for Long Dry Periods?

How Do Cacti Store Water for Long Dry Periods?

仙人掌如何长期储存水分?

  1. Cacti have thick, fleshy stems that act like water tanks.
  2. Their skin is waxy to stop water from evaporating in hot air.
  3. Spines are modified leaves that reduce surface area and shade the stem.
  4. Roots spread wide and shallow to catch rainwater fast when it falls.
  5. They open tiny pores only at night to take in carbon dioxide.
  6. This saves water compared to daytime breathing used by most plants.
  7. Some cacti hold hundreds of liters — enough to last over a year.
  8. Even in drought, their stored water keeps them green and alive.
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