The impact of water abstraction on hydromorphological, physico-chemical parameters and on periphyton community in the River Oplotnica | Ocena vpliva odvzema vode iz vodotoka Oplotnica na hidromorfološke in fizikalno-kemijske dejavnike ter na združbo perifitona

anglais. From May to August 2007, sampling of periphyton, estimation of hydromorphological, physical and chemical parameters on the Oplotnica river were performed. The sampling sites were selected in the water abstraction area of the Oplotnica river for the purpose of small Hohler and Oplotnica hydroelectric plants. The impact of water abstraction on the hydromorphological, physical and chemical parameters as well as on the community structure and relative abundance of periphyton was estimated. The results showed changes of hydromorphological parameters at sampling sites affected by water abstraction. Physical and chemical parameters, species composition and relative abundance of periphyton did not alter along the water course to a large extent. Smaller differences in species composition and relative abundance of periphyton were noticed due to different types of water habitats. The Bray–Curtis coefficient of similarity demonstrated the periphyton community to be more time than place dependent. The Pantle–Buck Saprobic index classifies the Oplotnica river in the I. and I.-II. class according to the quality, which gives evidence that water in the water course was not polluted or polluted to a minor extent.

slovène. V obdobju od maja do avgusta 2007 smo na vodotoku Oplotnica vzorčili perifiton, ocenili hidromorfološke ter merili fizikalne in kemijske dejavnike. Odvzemna mesta smo izbrali na območju odvzema vode za potrebe malih hidroelektrarn (MHE) Hohler in Oplotnica. Ocenili smo vpliv odvzema vode na združbo perifitona, na  hidromorfološke ter na fizikalne in kemijske dejavnike. Ugotovili smo spremembe hidromorfoloških dejavnikov na odvzemnih mestih, ki so pod vplivom odvzema vode. Fizikalni in kemijski dejavniki ter vrstna sestava in pogostost pojavljanja perifitona pa se vzdolž vodotoka niso veliko spreminjali. Manjše razlike v vrstni sestavi in pogostosti pojavljanja perifitona so posledica različnih tipov vodnih habitatov na posameznih odvzemnih mestih. Bray–Curtisov koeficient podobnosti je pokazal večjo časovno kot krajevno odvisnost. Vrednosti Pantle–Buckovih saprobnih indeksov uvrščajo vodotok Oplotnica v I. in I.–II. kakovostni razred, kar nam pove, da je bila voda v vodotoku Oplotnica v času vzorčenja neobremenjena oziroma malo obremenjena.