Ecosystem services associated with a mosaic of alternative states in a Mediterranean wetland: Case study of the Doñana marsh (southwestern Spain)

Aquatic systems can flip from clear water to turbid water states. Previous research in shallow wetlands from the northern temperate zone identify clear water states as the most socially desirable based on their enhanced capacity to host biodiversity and deliver ecosystem services. However, the degree to which this model stands for Mediterranean shallow wetlands remains largely unexplored. We analyse ecosystem services associated with alternative stable states in the Doñana marsh (southwestern Spain). First, clear and turbid water states of the marsh are identified. Then, four critical ecosystem services are characterized together with the key species, and ecosystem functions on which they depend. Ecosystem service performance under the alternative stable states is assessed combining qualitative and quantitative analysis of biophysical indicators. Our results describe a patchy mosaic in which clear water and turbid water states co-exist in the marsh. All ecosystem services analysed performed better in macrophyte-dominated clear water states. © 2011 Copyright 2011 IAHS Press.