Long-term artificial seawater irrigation as a sustainable environmental management strategy for abandoned solar salt works: The case study of Agua Amarga salt marsh (SE Spain)

• Combination of groundwater abstraction and seawater irrigation. Irrigation program helped keeping level near the salt-marsh surface. Soil salinity decreased in ponds continuously irrigated with seawater. contributed to increase plant cover long term. Groundwater is among main anthropogenic causes wetland desiccation worldwide, corrective measures must be taken avoid degradation this valuable ecosystems. A case study Agua Amarga salt marsh (≈180 ha) (SE Spain). includes a solar saltwork pond network operation between 1925 1975, when it was abandoned, were colonized by vegetation. In 2008 two desalination plants operating vicinity, which supplied groundwater. To mitigate possible negative impact on ecosystem due drawdown, 2009 sea water irrigation implemented. This paper summarizes results ten-year monitoring (2010–2020) evaluate effects levels quality, soil moisture, vegetation cover. During period, average 2.5 m below surface around 1 deep ponds. not affected outside saltmarsh, but inside, where saltworks caused values rise above 300 mS/cm, more than 150 mS/cm some 20 piezometers. Between 2012 2020, increased ≈10 ≈25 %, halophyte species such as Arthrocnemum macrostachyum Sarcocornia fruticosa being most favoured. areas prolonged flooding, Ruppia maritima , that lives submerged saline water, found. areas, electrical conductivity (1:5 soil:water extracts) from ≈7-14 mS cm-1 ≈2-6 cm-1. We present an example sustainable actions coastal wetland, exploitation resources semiarid combined promoting natural habitats.