The aim of the present research was to to determine the distrubution, abundance and frequency of macrophyte taxa in the river Ižica and to determine influence of physical and chemical factors of water on their distribution and to establish the relation between wider environment characteristics on macrophyte taxa abundance and distribution. In the growth season in 2016, we divided river Ižica into 26 connected and 12 separated stretches. In June, July, August and September, we performed 4 samplings. In all stretches, the presence, frequency and growth form of macrophytes were recorded. Physical and chemical parameters were measured and the status of the physical and biological condition was assessed, according to the Riparian, Channel and Environmental Inventory. In the separated stretches, habitat parameters were also determined. At 7 sampling sites, water samples were taken for later analysis of nitrates and phosphates, that was performed in the laboratory. We recorded as many as 40 taxa of macrophyte taxa, which are distributed differently according to environmental factors. We estimated the RCE status of the river Ižica, with exception of the 1. stretch that runs through Ig, the upper part is of the highest quality and the quality decrease downstreams. River Ižica was ranked from 2. to 5. RCE quality class. Diversity of macrophyte taxa is the highest in the middle part of the river Ižica. The frequency and abundance of the taxa are changing over the growth season, the highest at the peak of the growth season, in August. The highest abundance, especially in the lower part of the river Ižica, has filamentous algae and species Sagittaria sagittifolia and Potamogeton natans.
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