Solid manure heaps can be a significant source of ammonia,nitrous oxide and methane emissions. Nitrous oxide and methane are important greenhouse gases with respective global warming potentials 265 and 28 times higher than that of carbon dioxide.Nitrogen losses via ammonia volatilization during storage may contribute to eutrophication and acidification of the ecosystems.Ammonia and greenhouse gas emission can be influenced by promoting aerobic decomposition during storage.Addition of C-rich bulking agents, such as sawdust,may provide an approach to the reduction of ammonia and greenhouse gas emissions. In a laboratory experiment reported in this paper,the static chamber technique was used to investigate the effects of mixing ratios of sawdust on ammonia and greenhouse gas emissions from stored cattle manure.Three treatments were made:cattle manure without sawdust addition(CM),sawdust addition to the cattle manure at a manure-to-sawdust ratio of 2∶1(M2S1)or 1∶1(M1S1),(W/W,DM basis).Nine polyvinylchloride cylindrical(30cm in diameter and 90cm in height)static vessels were used to measure NH_3 and greenhouse gas emissions.Fresh cattle manure was collected from the Experimental Farm of Rongchang Campus of Southwest University in Chongqing.Having been thoroughly mixed,cattle manure was filled into 9barrels(24.2cm in diameter).The barrels were enveloped by static vessels while gaseous emission was measured.The stacking process commenced on September 27,2014,and gaseous emissions were measured from 9:00a.m.to 10:00a.m.for 90days.The air temperature was 16.5℃ (Maxmium: 24.6℃,Minimum:7.2 ℃),and the relative humidity was 92.6% (Maxmium:96.1%,Minimum: 77.1%)during the period of storage.The results showed that sawdust addition significantly affected NH_3 and greenhouse gas emissions from cattle manure during storage.Compared with CM,cumulative emissions of NH_3 and CH_4 from M2S1 and M1S1 were significantly smaller,and cumulative emissions were 16.00,4.54,and 7.05mg/kg for NH_3(p<0.05),and 839.87,81.24,and 65.69mg/kg for CH_4(p< 0.05)respectively.Conversely,cumulative emissions of CO_2 increased significantly with increasing sawdust addition,and were 8.41,59.76,and 83.83g/kg for CM,M2S1and M1S1,respectively.Cumulative emission of N_2O was significantly higher for M2S1(19.83mg/kg),but was significantly lower for M1S1(6.86mg/kg)than that of CM (11.23mg/kg).On the basis of 100-year global warming potential for CH_4 and N_2O,total greenhouse gas emissions were 26.55,7.55 and 3.68g/kg of manure weight based on CO_2 for CM,M2S1 and M1S1,respectively.Mixing with sawdust significantly decreased total greenhouse gas emissions from cattle manure by 71.57% for M2S1 and by 86.13% for M1S1 compared with CM.Mixing with sawdust during storage of cattle manure was shown to be an effective manure management practice to reduce ammonia and greenhouse gas emissions.