Factors Affecting Transpiration

• light intensity

  • brighter light, greater rate
  • stomate begin to close as it gets darker
  • photosynthesis can't happen in the dark, so they don't need to be open to let CO2 in
  • when the stomata are closed, very little water can escape
• temperature

  • warmer, faster rate
  • when its warm, water particles have more energy to evaporate and diffuse out of the stomata
• air flow:

  • the better the airflow, the greater the transpiration rate
  • if air flow is poor, water vapour just surrounds the leaf and doesn't move away. this means that there is a high concentration of water vapour outside of the leaf as well as inside of it, causing diffusion to happen more slowly.
• humidity:

  • the drier the air is around a leaf, the faster transpiration happens
  • similar to air flow