Physico-chemical characteristics and methanogen communities in swine and dairy manure storage tanks: Spatio-temporal variations and impact on methanogenic activity

► Swine manure characteristics exhibited significant spatial and temporal variations. ► Dairy manure storage tanks produced methane with a higher rate than swine ones. ► Volatile fatty acid concentrations had the strongest impact on methanogenesis. ► Methanoculleus spp. would be the major contributors to methanogenesis in manure storage tanks.