Environmental Features Formation of Algoflora Middle Flow Zarafshan River (Uzbekistan)

Abstract

Algoflora of the Zarafshan River was formed by the  integrated influence of environmental factors. The river is  divided into 3 parts and this part is distinguished by a  number of environmental factors such as the chemical  composition of water, water temperature, transparency, flow  rate, pH, etc. 331 species were identified in the river algoflora  and within the species taxon. The groups of algae are  analyzed by the ratio of water temperature, by mineralization  of water, by the habitat of algae, and indicator-saprobic  species. Water temperatures are crucial for the distribution  and development of algae. In the spring, 169 algal floras were  identified, in the summer of 210, in the autumn of 13 and in  the winter of 88 of algae. In the river algoflora, 16  eurythermal and 315 stenothermal algae species were  established. Mineralization of river water varies from beta oligagaline to alpha-oligogaline. The river waters are mainly  freshwater and in some places less often fresh-brackish. This  ensures the distribution of fresh-salt-water algae in the  middle and lower parts of the river. The river algocenoses are  distributed as follows: phytoplankton 62, phytobenthos 134,  phytoplankton-phytobenthos 66, periphyton 62 and epiphyte  7 int. From the river algoflora, 97 species and varieties of  saprobic-indicator algae were identified. Using these species,  the ecological and sanitary state of the river was determined.  Indicator-saprobic algae are not evenly distributed over the  seasons of the year.