Temperature significantly affects transpiration rates in plants, with higher temperatures generally leading to increased transpiration.
Plants transpire more rapidly at higher temperatures. This is because water evaporates more quickly as temperature increases. According to research, a leaf may transpire three times as fast at 30°C compared to 20°C. This happens because the higher the temperature, the greater the kinetic energy of the water molecules, making it easier for them to escape from the leaf's surface into the atmosphere.
| Temperature (°C) | Transpiration Rate (Relative) |
|---|---|
| 20 | 1x |
| 30 | 3x |
Factors contributing to the increased transpiration rate at higher temperatures include:
- Increased Evaporation: Warmer temperatures directly increase the rate of water evaporation from the mesophyll cell walls inside the leaf.
- Decreased Humidity: Higher temperatures often reduce the relative humidity of the air surrounding the plant. Drier air creates a steeper water potential gradient between the leaf and the atmosphere, driving more water out of the plant.
- Increased Diffusion: Heat speeds up the diffusion of water vapor through the stomata (small pores on the leaf surface) and into the surrounding air.
Therefore, understanding the impact of temperature on transpiration is crucial for managing plant water status, especially in agricultural settings.
