My research focuses on the potential effects of changes in climate on water resources in semiarid regions. We are viewing this through an ecohydrological lens; specifically, we want to see how changes in temperature and climate affect vegetation growth and how the vegetation in turn affects surface reservoir recharge. 







These two pictures were taken at the same site, the first in May 2010 and the second in July 2010. The difference in the grassy vegetation is typical of the spring to summer transition in Sardinia, where the summers are hot and dry. During our field campaign, we designed, constructed, and played our rainfall simulator (left) to test its performance in field conditions. The two video clips below show the system in action. The runoff from the system was measured using a tipping bucket flow gauge, which we constructed in the lab using the switch mechanism from a tipping bucket rain gauge. The password for both videos is "rain."






After running three experiments with the rainfall simulator, each with different initial soil moisture, we were able to model the observed cumulative runoff using varying values of the saturated hydraulic conductivity. These results emphasized the impact of the soil moisture on the runoff behavior. Our next steps will be to run similar experiments on plots with varying vegetation states (i.e. green vs. dormant) and fractions to simulate runoff response at different times of year.