Identifying areas of basin-floor recharge in the Trans-Pecos region and the link to vegetation

Comparative water potential and chloride profiles (∼10 m deep) collected from four vegetation communities in the Trans-Pecos region of the Chihuahuan Desert were assessed to evaluate the potential for using vegetation patterns as a means of efficiently improving large-scale estimates of basin-floor recharge in semiarid and arid regions. Analytical solutions and multiphase flow and transport modeling constrained flux histories and current fluxes across the water table at each site. Chloride bulge profiles containing ∼12–15 kyr of atmospheric deposition and long-term drying water potential profiles typified most desertscrub and grassland sites. In contrast, evidence of episodic sub-root zone percolation and chloride profiles containing