Estimate of degassing greenhouse gas emissions of the turbined water at tropical hydroelectric reservoirs

摘要

Biogenic gases generated underwater in hydroelectric reservoirs come from organic matter decomposition by microorganisms. There are 3 different pathways of emitting greenhouse gases (GHG). Gas emissions by impoundments are mainly methane (CH_4), carbon dioxide (CO_2) and nitrous oxide (N_2O) transported through bubbles formed by decomposing organic matter on the lake bottom, as well as rising up the lake gradient through molecular diffusion. Another gas emission pathway is the degassing of these gases at turbined water sites and along the river below the dam.