Greenhouse gas emissions from human-impacted rivers

Inland freshwater systems are sources to the atmosphere of greenhouse gases (GHGs) and as such, their importance in global GHG budgets is increasingly recognised. Outgassing of carbon dioxide, methane and nitrous oxide from these systems account for an estimated 3.9 Pg C/ yr of the 5.1 Pg C/yr exported globally from the terrestrial environment to freshwaters although considerable uncertainty about the accuracy of these estimated fluxes remains. Human-impacted rivers have not yet received the same level of consideration as 'pristine' systems in aquatic GHG budgets, yet more people now live in urban areas than rural areas and 68% of the world population are projected to live in urban area by 2050. This PhD programme will quantify concentrations and fluxes of GHGs across human-impacted catchments from source-to-sea, starting with the River Clyde in Scotland. Controls on the GHG loading profile will be explored using GIS catchment land cover analysis to develop a predictive model for catchment GHG emissions.