Characteristics of annual greenhouse gas flux and NO release from alpine meadow and forest on the eastern Tibetan Plateau

•Annual non-CO2 greenhouse gas and NO fluxes were measured in alpine meadow and forest.•CH4 uptake in alpine sites was generally lower than other Chinese grasslands and forests.•Alpine forest had high soil C content and N availabiltiy and thus large N-oxide fluxes.•Low CH4 uptake in the meadow was ascribed to high soil moisture and low gas diffusion.•Alpine forest showed higher net non-CO2 greenhouse gas emission than the alpine meadow.