Warmer temperature promotes the contribution of invertebrate fauna to litter components release in an alpine meadow on the Qinghai-Tibetan Plateau

•Warming accelerated the release of litter chemical components, especially cellulose.•Invertebrate fauna significantly accelerated the release of litter nitrogen and lignin.•The effects of invertebrate fauna on litter carbon release were mediated by season.•The effects of invertebrate fauna on litter lignin release were mediated by warming.•Litter components in warm season released faster than those in cold season.