Evaporation and the water balance

Abstract

In New Zealand most water reaches the land surface as rain. Some rain evaporates after being caught on the surfaces of plants (a process called interception), but the rest reaches the ground and usually soaks into the soil. Water in the soil is extracted by plants through their roots and, after passing through the stems and branches, evaporates through tiny leaf pores known as stomata, in the process called transpiration. Water also evaporates from the moist surface of the soil at a rate determined by energy availability, surface wetness, nature of the vegetation, and the availability of soil water.