Terrestrial hydrological processes

Field measurements of soil water content have many potential uses beyond merely monitoring changes in water storage of a soil profile. The neutron probe method has been applied widely to measure the effect of differences in evaporation losses from different vegetation on soil water balances. A number of key studies of unsaturated zone water balances in the UK were undertaken, with particular attention to the Chalk, which is the country's most important aquifer. Much of the classical work in soil physics assumes that water flows in a regular fashion through a soil matrix which is homogeneous, or at least comprises a series of identifiable layers with uniform properties. Soils exert a key role on the hydrology of an area influencing the distribution of rain water between evaporation, runoff and recharge. The primary flood reducing role claimed for planting hedge lines and trees may be more subtle than thought.