When it is short of water, a plant, which normally USES evaporation as a means of cooling, cannot rid itself of the heat it absorbs from sunlight or the heat that may build up from its own metabolism.
When it is short of water, a plant normally USES evaporation as a means of cooling.
在缺乏水分时，植物一般用蒸发作为降温的手段。
3
The actual water requirements differ according to plant, climate (most of the water withdrawn by plants is for cooling through evaporation) and the efficiency of irrigation.