Distribution of the invasive alien species Cotula coronopifolia L. (Asteraceae) relating to water halinity and sodicity in the Variconi wetland (Campania, southern Italy)

Invasive alien species represent one of the main environmental threats to native biodiversity and can also strongly alter the biogeochemical cycles within an ecosystem. This study aims to define the distribution of the invasive alien species Cotula coronopifolia L. within the protected wetland “Variconi” (Campania region, southern Italy) and evaluate the potential role of water geochemical features as interpretation tools for pattern distribution. The presence of C. coronopifolia was assessed in the field, and a distribution map was drawn; concomitantly thirty-nine water samples were collected from groundwater and surface water bodies for chemical analyses. The results showed that C. coronopifolia preferentially colonized the sector of the wetland characterized by high halinity, while it is totally absent in retrodunal and sandy coastal area with very high halinity. The cartography presented can be used as a tool to help target future management interventions. Through our multidisciplinary approach, new evidence has been provided on the ecology of this invasive alien plant that occupies several wetlands worldwide. The replicability of this method may be useful to assess the level of invasion of an alien species but also to predict its evolution as a function of environmental parameters.