Distribution survey and some biological aspects of Water Hyacinth in Anzali Wetland, Guilan province

Water Hyacinth, Eichhornia crassipes is one of the world’s worst weeds. It originates from Amazonia and be invader to other areas in the worldwide. It has recently been detected in several natural areas of northern part of Iran such as Anzali Wetland. Here, distribution of Water Hyacinth was studied in Anzali Wetland during 2015-2018. Also some biological characteristic including; evapotranspirative water losses, surveillance against salinity gradients and nutrient effect on biomass production of root and green parts were investigated. Water Hyacinth infestation was observed from 7 to 84 points of Anzali Wetland with 100 to 1000 m2 in different years. The distribution of Water Hyacinth was limited in summer of 2017 because of a prolonged temperatures below freezing winter. The seed was germinated in study area after two years. The water losses were estimated up to 2.5 times more from Water Hyacinth compared to open water. While the mortality of Water Hyacinth was observed in salinities more than 5.2 g.l-1, the leaves was increased in salinities lower than 1 g.l-1. The biomass of root was more than biomass of green part in areas with lower nutrient while it was versus in regions with high nitrogen level. Water Hyacinth has a high risk threat in the most water bodies in northern Iran because of the favorite climate situation and high eutriphication level. A multidisciplinary approach should be designed in the fight against Water Hyacinth in Anzali Wetland that awareness raising among local communities and the stakeholders is the most important.