construction of dams submerge large areas of forests. contribute it with green house effect

Construction of large dams leads to the production of green house gas and thus they may contribute to changes in the climate of Earth. For instance, warm climate dams or reservoirs produces methane gas which is a greenhouse gas. It is generated when the dams are stratified and the bottom layers become lack oxygen which in turn lead to degradation of biomass by the process called “anaerobic processes”. Thus, the hydroelectric dams are the major source of emission of methane gas originated by us and these gases contributes much more adverse affect to the change in climate than that of carbon dioxide.