Abstract: Periphytic algae are the major component of primary producer in freshwater ecosystems, and play an important role in nutrient cycling and distribution of submerged macrophytes. Based on the previous studies in periphytic algae ecology, we elucidated the community composition, ecological function and their main affecting factors, pointed out that periphyton algae could adapt to various environmental conditions by changing the composition of dominant species in the community, and elaborated the role of periphytic algae in nutrient cycling and the interaction between periphytic algae and submerged macrophyte. With regard to lake eutrophication, the future research topics about freshwater periphytic algal ecology include: interaction effects of main factors such as weak light and high concentration of nutrients on periphytic algae, the role of epiphytic algae in the biogeochemical cycling of carbon, nitrogen and phosphorus in lakes by insitu experiments, and the mechanism of the interaction between periphytic algae and submerged macrophyte in the eutrophic lakes.

Key words: land use, Dongting Lake area, ecosystem service value, spatial pattern, space-time evolvement