Wet Ecosystems in the Arid Southwest 

Multiscale Perspectives From a Landscape Where Water is Everything

Wet ecosystems in the arid southwest region of the United States (river systems, spring and seep systems, and wetlands) differ from much of the rest of the continent in being unique features embedded in an extensive matrix of very dry upland areas. Many of these ecosystems, even portions of the larger rivers, are ephemeral or intermittent, and many or even most of the spring and wetland systems depend on recharge from groundwater. They provide water to huge metropolitan areas hundreds or even thousands of miles away, as well as many small, scattered local communities. They are the areas of greatest biological diversity in the region, but many have also been heavily altered by invasive species. Their biological values and critical importance to humans make them the most valuable resource in the arid southwest, but conflicting conservation and anthropogenic values, especially in a shifting climate, make their management among the most complex challenges in the nation.