Meteorological term for the sum of transpiration and evaporation, i.e. the evaporation of water from animals and plants, as well as the soil surface. The amount depends on the factors of humidity, cover and water content of the soil, temperature of the air layers close to the ground, temperature of the earth or water surface, exposure (solar radiation) and wind speed at the earth's surface. In plants such as vines, transpiration is the controlled evaporation of water from the plants via the guard cells, especially the leaves. However, plants evaporate some water even when the air is dry and the cells are closed, as the epidermis is never 100% dense. See also water storage capacity and water evaporation.
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Andreas Essl
Autor, Modena