Investigating the Impact of Climate Change on Groundwater Recharge Using a High Precision Meteo Lysimeter in a Dune Belt of the Doñana National Park

Abstract

Although precise weighing lysimeters are mostly installed for agricultural purposes in crop-producing areas, these instruments are also useful in areas of ecological interest where soil and aquifer recharge-discharge processes need to be better understood. In September 2015 a high precision meteo-lysimeter was installed in a coastal dune of the Doñana Natural Reserve to quantify the recharge in dune belts, and to estimate its dependence on regional climate trends. In addition to the lysimeter, also six soil moisture sensors (model CS650) and 2 meteorological stations were installed. The first results show recharge rates of natural precipitation ranging from 19 to 97%, depending on the meteorological conditions and the initial soil moisture. The lysimeter-measured rainfall generally exceeded the measurements of the tipping bucket. Also the contribution of the dew was detected by the lysimeter. A soil water model is currently being set up to simulate recharge, soil water movement, evaporation and percolation, as well as to quantify uncertainty and noise effects.