Saline marshlands of the Maltese Islands

Abstract

The saline marshlands of the Maltese Islands are coastal wetland biotopes defined by the presence of brackish water and a substratum of sandy/silty sediment. These habitats form at the mouth of valley systems where freshwater and sediment from inland sources interact with seawater. They are sparsely distributed round the Maltese coastline and often degraded by anthropogenic pressures. The natural hydrological cycles of the marshes follow the seasonal patterns of precipitation, where a wet phase, during which surface water is present, alternates with a dry phase. In managed marshes, the hydrological balance may be partly independent of climatic forcing and would depend more on specific management practices. The saline substratum supports halophytic vegetation whilst the water body is colonised by fauna typical of temporary waters or of brackish waters, depending on the duration of the hydroperiod. The substratum also functions as a repository for propagules, such as eggs, spores and seeds. This provides a ‘storage effect’, where reproductive failure in one year may be compensated for by germination or hatching of propagules deposited during previous seasons.