Responses of a saline lake ecosystem in a semiarid region to irrigation and climate variability - The history of Salada Chiprana, central Ebro basin,Spain

To adequately manage the fragile and changing environments of semiarid regi ons it is essential to disentangle human from climate or other environmenta l impacts over longer timescales than human memory. We investigated sedimen t cores from Salada Chiprana, a saline lake in the central Ebro basin in Sp ain, using pollen, charcoal, sedimentological, geochemical and radiometric dating techniques. The sequence indicates a rapid evolution from an ephemer al playa lake during the Late Holocene to a permanent saline lake a few cen turies ago. The limnological evolution correlates with changes in agricultu ral practices and provides evidence of the strong impact of irrigation on t he lake's hydrological balance from the XVth century. The work demonstrates that the Salada Chiprana, the only permanent, relatively deep, hypersaline lake in Spain has been created by a long history of human interaction with the landscape.