stomatal transpiration
Technical term in botany for water vapor loss through stomata.
Stomatal transpiration plays an important role in water regulation in plants.
蒸散 is the general term for transpiration, while 気孔蒸散 specifies transpiration through stomata.
気孔 refers to the stomata themselves, the pores on plant leaves.
Compound of 気孔 (stoma) and 蒸散 (transpiration).