ABSTRACT
A Conceptual Model ..................................................................... 291 13.3 Results and Discussion ............................................................................. 292
13.3.1 MAP-EVI Regional Function ........................................................ 292 13.3.2 EVI Dynamics along a Groundwater Dependence
Gradient at the Telteca Site ........................................................... 292
Groundwater-dependent ecosystems (GDEs) play a key role in human development, and are especially relevant in regions with low rates of rainfall, by providing a broad range of ecosystem services such as physical support for wildlife habitats and biodiversity hotspots, control of floods and erosion, regulation of nutrient cycling, or provision of landscape refuges for cognitive development (de Groot et al. 2002; Chen et al. 2004; Eamus et al. 2005; Bergkamp and Katharine 2006; Ridolfi et al. 2007). During the past decade, research on ecology and functioning of GDEs has received a growing interest from the scientific community and from landscape managers. However, in spite of their high intrinsic values, many of these ecosystems have been strongly impacted as a consequence of disruption of hydrological linkages with groundwater resources. This disruption has been generally promoted by excessive rates of groundwater extraction and depletion, for example, Las Tablas de Daimiel and Doñana National Reserves in Spain (Llamas 1988; Muñoz-Reinoso and García-Novo 2005); Swan Coastal Plain in southwest Australia (Groom et al. 2000); desert springs in the Mojave and Great Basin deserts in the United States (Patten et al. 2008); San Pedro River in the United States (Stromberg et al. 1996). It has also been caused by modification of morphology of stream channels or wetlands through dredging or artificial diversions (Ellery and McCarthy 1998) or as a consequence of changes in their water balance due to climatic factors (Murray-Hudson et al. 2006). A better understanding of the functioning and water consumption of GDEs is then critically required to evaluate the ecological services provided by them (Murray et al. 2006; Brauman et al. 2007) and, for developing adaptive management frameworks that reconcile compatible human activities, ecosystem conservation, and their underlying hydrological tradeoffs under future scenarios of land use and climate change (MacKay 2006; Barron et al. 2012b).
