Evaluation of trophic parameters in newly built reservoir using canonical variates analysis

Abstract

Wielkopolska region has precipitation below country average and water shortage is especially visible during spring and summer, thus regeneration of water bodies play important role in saving of water reserves in rural areas. The newly built water reservoir is located in Nienawiszcz, Rogoźno commune, Poland. The aim of study was to compare experimental sites according to parameters describing water trophy like chlorophyll a, dry mass of seston, total organic carbon, biochemical oxygen demand and according to concentrations of nitrogen and phosphorus compounds. Sites were compared using location in reservoir and year season. In the year 2014 (after connection of both parts of lake) part A and B of reservoir had similar trophic conditions, thus confirming stabilisation of the reservoir as an initial freshwater ecosystem. Water table level was also stable, thus low average water depth was not affected water quality Based on canonical variates analysis it was showed, that changes of nitrates and total nitrogen concentrations strongly affected the variability of experimental objects in comparison to concentrations of nitrites and total phosphorus. In the year 2014, after connection of both parts A and B the reservoir start to stabilise in case of similarity of water quality parameters in surveyed sites.