Invasion history and distribution of the aquatic alien Elodea canadensis (Hydrocharitaceae) in Turkey

Abstract

Submerged macrophyte Elodea canadensis Michx. is a non-native species to Turkey where it was first recorded in 1982. In this study, we aim to provide the current distribution of E. canadensis in Turkey with notes on its invasion history and ecology. We performed field studies to measure the physical and chemical parameters of the invaded lakes. Our study is based on new field works, herbarium specimen examination and literature survey. As a result of our findings, E. canadensis has invaded 15 wetlands in eight water basins of Turkey. Eleven of the invaded wetlands, including the largest freshwater lake of Turkey have protection forms ranging from national parks, nature parks to nationally/locally protected areas. Type of the wetlands are also diverse, like drainage canals, ancient pools, karstic, crater, tectonic and alluvial set lakes with trophic status from oligotrophic to eutrophic. Physico-chemical parameters measured in seven invaded wetlands are as follow: Water temperature between 15.5 and 22.3 °C, pH between 7.1 and 8.6, dissolved oxygen as 3.7–8,8 mg l-1, electrical conductivity as 230–610 µS cm-1, salinity between 0.1 and 0.29 ppt, and ammonium as 0.25–0.74 mg l-1. The altitude range of the colonized wetlands is between sea level and 2100 m a.s.l. Elodea canadensis forms single species stands in many sites, but we could totally record 22 accompanying macrophyte taxa in species rich habitats. Here we present the most comprehensive distribution and ecology data for E. canadensis in Turkey which could be used for further research and management to understand its future spread and effect on native vegetation.