Shaping changes in the ecological status of watercourses within barrages with hydropower schemes – literature review

Abstract

Hydropower use of watercourses has tangible consequences for the environment, society and economy. Based on a literature review and their own research, the authors present current data on changes in the ecological status of waters within run-of-river and reservoir hydropower plants, i.e. changes in biological elements (benthic macroinvertebrates, plankton, ichthyofauna, macrophytes), as well as hydromorphological and physicochemical changes. Previous researchers have noted that the impact of hydropower use of rivers on ecological status of those rivers is extensive, consisting of, among others, changes in species structure and populations of macrophytes, benthic macroinvertebrates, plankton and ichthyofauna (positive as well as negative changes), algal blooms due to increased turbidity, constrained migration of water organisms, changes in temperature within hydroelectric power plants, the phenomenon of supersaturation, eutrophication, changes in hydrological conditions (e.g., increased amplitudes of diurnal water levels and their consequent annual reduction), and increased erosion below the damming and deposition of bottom sediments on the damming barriers. In addition to such changes in ecological status, hydropower use also has a visible impact on socio-economic conditions (e.g., living standards of the population) and the environment (e.g., quality of bottom sediments and biodiversity). The article offers an assessment of the impact of hydropower use of rivers on ecological status (biological, hydromorphological, physicochemical elements and hydrological conditions of such rivers), society, economy and environment; it also proposes a research scheme to assess the impact of hydropower structures.

Keywords

• hydropower plants
• ecological status
• water quality
• rivers
• environmental impact
• aquatic organisms
• hydromorphology
• physicochemistry
• hydrology