shallow freshwater river with clear water and dense vegetation, yellow water-lily and hornwort survive, covered with algae

air algae aquatic background balance biotope brandybottle brook bubble ceratophyllum challenge clear climate coldwater colorful concept contrast covered crystal current day demersum dense detritis detritus disaster ecology ecosystem environment environmental europe flora flow freshwater gravel ground hornwort human impact lake litter lush lutea moderate movement nature nuphar plant podillya ray river sand season shallow stream strong substrate summer sun sunny survive temperate threat ukraine underwater vegetation vulnerable water waterlily wave wet wonder yellow