Warming and nitrogen(N)addition may impact soil nitrous oxide(N_(2)O)emissions,but the relationship between plant community composition and soil microbial activities remains unclear.For a two-year field study in the Q...Warming and nitrogen(N)addition may impact soil nitrous oxide(N_(2)O)emissions,but the relationship between plant community composition and soil microbial activities remains unclear.For a two-year field study in the Qinghai-Tibet Plateau,open-top chambers were used to quantify the effects of warming,N-addition,and their interactions on N_(2)O emissions.We found that the N-addition greatly increased N_(2)O emissions by 77.4%in 2018 when compared to the control group.In contrast,warming showed little effect on N_(2)0 emissions but did increase the activity of enzymes associated with soil nitrification and denitrification.A combined effect of warming and N-addition of resulted in 208.6%(2018)and 90.8%(2019)increase in N_(2)0 emissions,respectively,compared to the individual treatments of warming or N-addition.Global warming in alpine meadows is causally linked to increased legume biomass which is further intensified with the N-addition.Intensified legume biomass(p<0.05),soil moisture(p<0.001)and enzyme activity(p<0.001)had a positive effect on N_(2)0 emissions,while diminished microbial carbon/nitrogen(MBC/MBN)(p<0.05)correlated with reduced N_(2)O emissions.Final results indicated that N-addition has a positive effect on N_(2)O emissions,and the addition of warming further intensifies this effect.The increased dominance of legumes and microbial N content contributes to this effect.These outcomes suggest that warming and atmospheric N deposition can stimulate N_(2)O emissions of alpine meadows inthefuture.展开更多
基金the National Natural Science Foundation of China(U20A2009,41991234,42077422 and 41725003)the National Key Research and Development Program of China(2022YFF1301801)the Major Science and Technology Projects in Tibet(XZ202101ZD0007G and XZ202101ZD0003N).
基金supported by National Natural Science Foundation of China (32171590)Second Tibetan Plateau Scientific Expedition and Research Project (2019QZKK0307)+1 种基金Nagqu Science and Technology Project (NQKJ-2023-02)Youth innovation Program of Chinese Academy of Agricultural Sciences (Y2023QC08).
文摘Warming and nitrogen(N)addition may impact soil nitrous oxide(N_(2)O)emissions,but the relationship between plant community composition and soil microbial activities remains unclear.For a two-year field study in the Qinghai-Tibet Plateau,open-top chambers were used to quantify the effects of warming,N-addition,and their interactions on N_(2)O emissions.We found that the N-addition greatly increased N_(2)O emissions by 77.4%in 2018 when compared to the control group.In contrast,warming showed little effect on N_(2)0 emissions but did increase the activity of enzymes associated with soil nitrification and denitrification.A combined effect of warming and N-addition of resulted in 208.6%(2018)and 90.8%(2019)increase in N_(2)0 emissions,respectively,compared to the individual treatments of warming or N-addition.Global warming in alpine meadows is causally linked to increased legume biomass which is further intensified with the N-addition.Intensified legume biomass(p<0.05),soil moisture(p<0.001)and enzyme activity(p<0.001)had a positive effect on N_(2)0 emissions,while diminished microbial carbon/nitrogen(MBC/MBN)(p<0.05)correlated with reduced N_(2)O emissions.Final results indicated that N-addition has a positive effect on N_(2)O emissions,and the addition of warming further intensifies this effect.The increased dominance of legumes and microbial N content contributes to this effect.These outcomes suggest that warming and atmospheric N deposition can stimulate N_(2)O emissions of alpine meadows inthefuture.
