A review of the impact of hydropower reservoirs on global climate change

Three types of greenhouse gases (GHGs), namely carbon dioxide, methane and nitrous oxide emitted from reservoirs have an important but often ignored impact on the climate change. Based on the literature, this paper presents a comprehensive assessment of the long-term impact of GHGs generated by hydropower reservoirs, the systems for monitoring and assessing reservoir GHGs, the mechanism for their generation and key factors involved. Using limnology theory as a basis, the biogeochemical cycle of carbon in the environment is understood to be the main mechanism for generating reservoir based GHG emissions. A summary of relevant research in South American tropical rain forests and the Canada's temperate zone, also shows the extent of current systematic analysis of GHG emission research. Proposals are made for more comprehensive data collection from a wider variety of sources and the key problems identified that need to be solved to provide a theoretical basis for future development policies and practice. (C) 2019 Elsevier B.V. All rights reserved.