Flora and vegetation of the Sheksna reservoir.

摘要

During the last 25 years (1970-1995) the flora of macrophytes in the Sheksna reservoir has increased from 91 to 222 species (of 54 families). These included fully aquatic and emergent wetland plants. The species belonged to six ecological types, hydrophytes, helophytes, hygrohelophytes, hygrophytes, mesohygro- and mesophytes. Among them the hygrophytes are the most numerous (108 species), but the highest phytocenotic contribution was made by the hydrophytes and helophytes. An analysis of natural habitats indicated that the species occupying wide areas predominated. The structure of the vegetation was also studied. The degree and pattern of the overgrowth in different parts of the reservoir differed depending on the indentation of the shoreline, presence of resources, the substrate, the submerged area and hydrology. Overall the reservoir had a low degree of overgrowth (2.5% of aquatic and 12.2% of littoral plants up to 2 m in depth).