International Scientific Journals
of Scientific Technical Union of Mechanical Engineering "Industry 4.0"

The presence of endemic species in Lake Ohrid exhibit significant spatial variation, related to prevailing climate, lake morphology and fluvial input into the lake. The high biodiversity of the lake was supported by the subaquatic inflow of cool, effects of climate change on the entire lake ecosystem, affects deep water oxygen availability, nutrient cycling and trophic linkages may yet be profound as the structure of the endemic diatom taxa. The dilution of time by time lake waters with pure spring waters is important for the oligotrophic status of Lake Ohrid and its subsequent low algae productivity. We found the highest number of endemic species at different depths from the lake shore, compared to the littoral area, where almost endemic species are either very widespread or almost absent.

The aim of this study is to determine the species of different diatoms genius and to evaluate the ecology status of the river. Samples were collected along the Valbona River during 2015 period. Diatoms have proven to be powerful indicators of environmental conditions with changes in species assemblages providing information on changes in environmental conditions. Many species are identified and the dominant taxa were: Diatoma vulgaris, Diatoma ehrenbergii, Diatoma mesodon, Meridion circulare, Fragilaria arcus, Fragilaria capucina, Cocconeis placentula, Cymbella affinis, Gomphonema tergestinum, Navicula tripunctata etc. Diatom communities can be described by their species composition and diversity. Based on the type of taxa and the ecological values of species, Valbona river belong to oligo-saprobic state.