模拟氮沉降对入侵植物藿香蓟与伴生种铁苋菜竞争关系的影响  

Effects of simulated nitrogen deposition on the competitive relationshipbetween invasive Ageratum conyzoides L.and its co-occurring indigenous forb Acalypha australis L.

作　　者：陈旭波[1] 陈健春 张亚芬 骆争荣[1] 贾静[1] CHEN Xubo;CHEN Jianchun;ZHANG Yafen;LUO Zhengrong;JIA Jing(College of Ecology,Lishui University,Lishui,Zhejiang 323000,China;Tourism College of Zhejiang,Hangzhou,Zhejiang 311231,China)

机构地区：[1]丽水学院生态学院,浙江丽水323000 [2]浙江旅游职业学院,浙江杭州311231

出　　处：《生物安全学报(中英文)》2025年第1期53-59,共7页Journal of biosafety

基　　金：浙江省自然科学基金(LY20C030002);浙江省教育厅科研项目(Y202249963)。

摘　　要：【目的】探究氮沉降对入侵植物与本地植物竞争关系的影响,阐明其如何改变物种竞争能力并影响入侵植物。【方法】以入侵植物藿香蓟和本地植物铁苋菜为对象,开展de Wit替代竞争试验。通过浇灌不同浓度的NH 4Cl溶液模拟不同氮沉降水平对植物株高、地上生物量和分枝数的影响。相对邻株效应指数(R NE)和取代系列图表被用来评估两者的竞争关系。【结果】单种栽培时,中高氮处理(6和12 g·m^(-2)·a^(-1))对藿香蓟收获时株高生长和地上生物量有显著的促进作用,而氮处理组显著提高了铁苋菜收获时株高生长和地上生物量。两种混栽时,不管哪种栽培比例下,藿香蓟收获时株高在各个氮处理组之间均无显著差异;收获时高氮组的铁苋菜株高均显著高于对照组。中高氮处理显著提高了藿香蓟在中高栽培比例(0.50和0.75)下的分枝数;高氮处理显著提高了铁苋菜在高栽培比例下的分枝数。R NE表明藿香蓟在高栽培比例时,铁苋菜对其氮处理组的竞争作用并不显著;铁苋菜在高栽培比例时,氮处理提高了藿香蓟的竞争力,低氮处理(3 g·m^(-2)·a^(-1))时其竞争最为明显。取代系列试验图表明,在任何混种方式下铁苋菜实际生物量均低于预期;低氮处理时,高栽培比例下的藿香蓟地上部分生物量和混种总生物量均高于预期值。【结论】氮沉降显著影响了藿香蓟与铁苋菜的生长及其种间竞争关系。氮沉降特别是低氮沉降增加了藿香蓟的竞争优势。【Aim】In order to further understand the effect of nitrogen deposition on the competitive relationship between invasive and indigenous species,and to elucidate how it changes species competitiveness and affects invasive plants.【Method】A de Wit replacement competitive experiment with the invasive plant Ageratum conyzoides and the native plant Acalypha australis was performed.The effects of different levels of nitrogen deposition on plant height,aboveground biomass and number of branches were simulated by watering different concentrations of NH 4Cl solutions.Relative neighbor effect(R NE)and replacement diagrams were used to estimate interspecific competition.【Result】In monoculture,medium and high nitrogen treatments(6 and 12 g·m^(-2)·a^(-1))significantly promoted the height growth and aboveground biomass of Ageratum conyzoides at harvest.whereas,the nitrogen treatment group significantly increased the height growth and aboveground biomass of Acalypha australis at harvest.When two species are mixed,regardless of the cultivation ratio,there was no significant difference in plant height between different nitrogen treatment groups during the harvest of Ageratum conyzoides.At harvest,the height of the Acalypha australis in the high nitrogen group was significantly higher than that in the control group.Medium and high nitrogen treatments significantly increased the number of branches of Ageratum conyzoides at medium and high cultivation ratios(0.50 and 0.75).Under high cultivation ratios,high nitrogen treatment significantly increased the number of branches of Acalypha australis.R NE showed that at high cultivation ratios,the competitive effect of Acalypha australis on nitrogen treatment groups of Ageratum conyzoides was not significant.When the cultivation ratio of Acalypha australis was high,nitrogen treatment improved the competitiveness of Ageratum conyzoides,and it was most obvious under low nitrogen treatment(3 g·m^(-2)·a^(-1)).The replacement diagrams showed that the actual biomass of Acalypha aust

关 键 词：氮沉降 种间关系 竞争 藿香蓟 铁苋菜 

分 类 号：Q948.1[生物学—植物学]