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外来植物的成功入侵常常表现为3种对策:逆境成功型、顺境成功型和两者兼备型.为了在植物群落水平探讨这些对策,我们研究了土壤无机氮组成和水平对入侵植物及其同属本地植物成功定植的影响.在实验中,我们选择21种植物(8种入侵植物、8种本地同属植物、5种本地非同属植物)构建人工植物群落,将每种群落置于3种氮组成(3∶1、2∶2、1∶3硝铵比)和3种氮水平(低氮、中氮、高氮)构成的9种氮处理中.主要测定指标包括:总生物量、相对生物量(指示物种成功)、死亡率和死亡时间.当同时考虑9种氮环境时,入侵植物与同属本地植物具有相似的总生物量、相对生物量和死亡时间,但前者的死亡率较低.这种格局与两者间相似的生长和忍耐性有关.氮组成影响死亡时间,氮水平影响总生物量和相对生物量.最重要的是,物种来源、氮组成和氮水平共同影响总生物量、相对生物量和死亡时间.这些结果表明:生长在系列氮环境中的入侵植物与同属本地植物可能具有相似的成功定植,氮组成和氮水平共同决定外来植物的成功入侵.“,”Aims Successful plant invaders usually exhibit three strategies:Jack-of-all-trades(more robust in stressful sites),Master-of-some(more responsive in favorable sites)and Jack-and-master(both robustness and responsiveness).To revisit these strategies,we examined how soil inorganic nitrogen(N)compositions and levels influence the success of native and invasive plant congeners in the context of plant communities.Methods We conducted an experiment involving three fixed factors:species origin,N composition and N level.Here,we selected 21 plant species(eight pairs of invasive and native congeners and five non-congeneric natives)to assemble plant communities,which were subject to nine N environments consisting of three N compositions(3∶1,2∶2 and 1∶3 NO3-/NH4+)and three N levels(low,medium and high N).We determined the following metrics:total biomass,relative biomass(a proxy of species success),mortality rate and mortality time.Important Findings Across nine N environments,native and invasive congeners exhibited similar total biomass,relative biomass and mortality time,but invaders had a marginally lower mortality rate than natives.Similar success between native and invasive congeners was linked to their similar growth and tolerance.N compositions influenced mortality time and N levels affected the total biomass and relative biomass.Importantly,species origin,N composition and N level interactively affected the total biomass,relative biomass and mortality time.These findings suggest that native and invasive plant congeners may be similarly successful across different N environments,and that inorganic N compositions and levels both contribute to plant invasion success.