两种不同类型凋落物分解和胞外酶活性对降雨减少的响应

[Objective]The aim of this study was to explore these responses in two subtropical litter species under reduced precipitation.[Method]Precipitation manipulation experiment was conducted to explore the impacts of reduced precipitation on mass remaining and extracellular enzyme activities(β-glucosidase,β-N-acetylglucosaminidase,cellobiohydrolase,acid phosphatase,and leucine aminopeptidase)in contrasting litter species(evergreen Cinnamomum austrosinense vs.deciduous Toona ciliate)in southwestern China.Three throughfall reduction levels were investigated:control without throughfall reduction,25%,and 50%throughfall reduction.[Result]Reduced precipitation often inhibited decomposition rates but stimulated the extracellular enzyme activities of both litter species.These positive effects were dependent on litter type and sampling date.The remaining litter mass was positively correlated with the activities of β-glucosidase,cellobiohydrolase,and β-N-acetylglucosaminidase.As a consequence,both litter decomposition and enzyme activities showed divergent responses to reduced precipitation in the two subtropical litter species.[Conclusion]Reduced precipitation decelerates litter decomposition but promotes extracellular enzyme activities in two contrasting litter species.These findings emphasize the divergent responses of litter decomposition and extracellular enzyme activities in subtropical regions experiencing significant precipitation reduction.