Introducing the invasive species, Tradescantia fluminensis for the flora of Iran, with emphasis on its risk assessment

During the study of the habitats and ecosystems of Gilan province (north of Ian), an invasive and alien species, namely, Tradescantia fluminensis (Commelinaceae) was observed and identified which is reported for the first time for the flora of Iran. In recent years, T. fluminensis has been developed as a weed in tea gardens and an invasive plant in the neighboring plains of the northern parts of Iran. In addition, the report of the growth localities as well as the risk assessment of the invasive plant were examined using the protocols provided by Virtue & Meland (2003), and Stone (2008). According to the risk score obtained for this invasive plant (205.86), it stands within the group of plants with "very high risk". By studying the soil of habitats, it was found that, there is a positive and significant correlation between the amount of available soil phosphorus and the wet biomass of the plant. Due to the ecological behavior of this plant, biological control and mechanical removal are the most appropriate methods of managing this plant in the northern habitats of the country.