Integration of Plant and Groundwater Interactions - Introduction to Phytoremediation of Contaminated Groundwater - page 42

Why is this information important to the phytore-
mediation of contaminated groundwater? The incident
solar energy that reaches a site of groundwater contamina-
tion ultimately provides the energy that is used to affect the
local water budget to either prevent recharge or to remove
groundwater from shallow contaminated aquifers. This
removal of energy in the form of evapotranspiration occurs
and can be quantified, especially with respect to changes in
depth to and fluctuations in the water table.

2.4 Summary

Up to 70% of continental precipitation is returned to the
atmosphere through evapotranspiration. In the extreme
case of arid areas, transpiration from plants can exceed the
amount of evaporation from the free surface of water; in
many instances, consumptive use—the natural mining of
groundwater resources by plants—can occur, and result in
net water discharge from a basin. As such, plant water use
has a major role in the global water budget, or hydrologic
cycle, and this includes transpired groundwater.