模拟氮沉降对鬼针草及其近缘本地植物的影响  

Simulated nitrogen deposition exacerbates the effects of invasive species Bidens pilosa and its native congener

作　　者：韦春强[1] 李象钦 唐赛春[1] 潘玉梅[1] WEI Chunqiang;LI Xiangqin;TANG Saichun;PAN Yumei(Guangxi Key Laboratory of Plant Conservation and Restoration Ecology in Karst Terrain,Guangxi Institute of Botany,Chinese Academy of Sciences,Guangxi Zhuang Autonomous Region,Guilin,Guangxi 541006,China;Zhejiang Provincial Key Laboratory of Plant Evolutionary Ecology and Conservation,Taizhou University,Taizhou,Zhejiang 318000,China)

机构地区：[1]广西壮族自治区中国科学院广西植物研究所,广西喀斯特植物保育与恢复生态学重点实验室,广西桂林541006 [2]台州学院,浙江省植物进化生态学与保护重点实验室,浙江台州318000

出　　处：《生物安全学报》2023年第1期25-32,共8页Journal of biosafety

基　　金：国家自然科学基金(31460165、31960282);广西自然科学基金(2018GXNSFAA281112);广西喀斯特植物保育与恢复生态学重点实验室项目(19-050-6、19-185-7);广西植物研究所基本业务费(201806)。

摘　　要：【目的】理解氮素增加对入侵植物与近缘共存本地植物生长和竞争的影响,可为预测全球氮沉降背景下入侵植物的风险评价和本地植物的保护提供依据。【方法】为模拟氮沉降,设置对照(无氮添加)、低氮(1 g·m^(-2)·a^(-1))和高氮(5 g·m^(-2)·a^(-1))添加3种处理,将入侵植物鬼针草及其近缘共存的本地植物金盏银盘分别单种和混种,比较它们在各处理下的生长(株高、分枝数和生物量等)和竞争[相对优势度指数(RDI)与相对互作强度指数(RII)]情况。【结果】无论有无竞争,高氮添加均显著增加鬼针草的生物量,降低其根冠比;无竞争时,高氮添加还显著增加其株高和分枝数。但高氮添加仅显著增加金盏银盘无竞争时的生物量。在所有氮处理下,鬼针草的RDI和RII均显著大于金盏银盘。高氮添加显著增加鬼针草的RDI,但其RII在所有氮处理间无显著差异;高氮添加显著降低金盏银盘的RDI和RII。【结论】高氮更利于鬼针草的生长,其在所有氮素处理下均有较强的竞争力和竞争耐受性,且高氮处理下竞争力更强。因此,全球氮沉降增加会加剧鬼针草对近缘本地植物的竞争抑制和入侵风险。【Aim】Several studies have shown that alien invasive plants have serious negative impacts on biodiversity,especially on native species that compete for similar resources.Global nitrogen(N)deposition can increase soil N availability,which may favor fast-growing invasive plants.However,whether invasive plants are superior to their native congeners,and whether the competitive relationship between them will be altered with increased N deposition remain unclear.Understanding these questions will help to predict alien plant invasion risks and protect native biodiversity under N deposition.【Method】We conducted a greenhouse experiment,in which invasive species Bidens pilosa and its native congener B.biternata were grown alone and together under three N addition treatments(CK:0 g·m^(-2)·a^(-1),low N addition:1 g·m^(-2)·a^(-1) and high N addition:5 g·m^(-2)·a^(-1)).We compared the growth(plant height,branch number,root/shoot ratio and biomass)and competition parameters of the invasive species and its native congener.【Result】High level N addition significantly increased the biomass and decreased the root/shoot ratio of invasive B.pilosa regardless of whether it was grown alone or grown together with B.biternata,and also enhanced the plant height and branch number of B.pilosa when grown alone.But high level N addition only enhanced the biomass of native B.biternata when grown alone.The RDI and RII of B.pilosa were greater than that of B.biternata under all N treatments.Furthermore,high level N addition significantly increased the RDI of B.pilosa whereas reduced the RDI and RII of the native congener.The RII of B.pilosa did not significantly differ among N treatments.【Conclusion】High level N is more favorable for the growth of B.pilosa than for that of B.biternata.The invasive species exhibit stronger competitive ability and more tolerance than its native congener under all N treatments,and the competitive ability was magnified under high N level.Global N deposition may exacerbate the competition inhibiti

关 键 词：氮沉降 鬼针草 近缘本地植物 生长 竞争 

分 类 号：Q948[生物学—植物学]