摘要
外来植物入侵对自然保护区的生物多样性造成了严重的威胁,掌握影响入侵植物成功定殖的关键因素对于其防控具有重要意义。植物入侵后会产生土壤遗留效应,这种效应会影响自身和其他入侵植物的萌发生长和竞争关系。该研究以两种外来入侵植物-飞机草(Chromolaena odorata)和鬼针草(Bidenspilosa)为研究对象,以广西恩城国家级自然保护区为研究区域,以飞机草入侵野外驯化的土壤为研究材料,设置飞机草未入侵(盖度为0%)、轻度入侵(盖度<50%)、中度入侵(盖度50%~90%)以及重度入侵(盖度>90%)四种处理的灭菌与未灭菌土壤对比试验,探究飞机草驯化后产生的土壤遗留效应对两种入侵植物萌发、生长以及竞争的影响。结果表明:①与未灭菌土壤相比,灭菌土壤中飞机草仅发芽,鬼针草的发芽率、株高、根长和生物量分别降低了63.9%、68.9%、58.1%和95.9%。②飞机草轻度入侵下的土壤微生物对鬼针草产生抑制作用,中度和重度入侵对其有促进作用,表明土壤遗留效应驱动了飞机草与鬼针草之间的入侵熔毁。③相对竞争强度(RCI)指数表明,共同入侵下,无论土壤灭菌还是未灭菌,鬼针草在入侵初期的竞争力均高于飞机草,且在飞机草中度和重度入侵下的土壤中鬼针草竞争能力更强。研究显示,由微生物介导的土壤遗留效应在外来植物入侵过程中起重要作用,并且入侵植物对土壤微生物的改变促进了其他外来植物的定殖与入侵。
Invasive alien plants pose a serious threat to biodiversity of natural reserves,and understanding the key factors influencing their successful colonization is crucial for their management.Invasive alien plants can lead to soil legacy effects,which impact the germination,growth,and competitive abilities of themselves and other invasive plants.This study selected two invasive plants,Chromolaena odorata and Bidens pilosa,within Encheng National Nature Reserve in Guangxi as research objects.We conducted a comparative experiment using soil from the areas invaded by C.odorata.Four levels of soil invasion by C.odorata,including no invasion(0%),light invasion(<50%),moderate invasion(50%-90%),and heavy invasion(>90%),along with soil sterilization,to explore the effects of soil microorganisms following the domestication of C.odorata on the germination,growth and competition of two invasive alien plants.Our results indicated that:(1)Compared with the unsterilized soil,only C.odorata germinated,and the germination rate,plant height,root length and biomass of B.pilosa were reduced by 63.9%,68.9%,58.1% and 95.9%,respectively.(2)The microbial communities in lightly invaded soil showed suppressive effects on B.pilosa,while the microbial communities in the moderately and heavily invaded soil showed promoting effects,indicating that soil legacy effects are responsible for driving the invasive meltdown between C.odorata and B.pilosa.(3)The relative competition intensity(RCI)index indicated that regardless of soil sterilization,B.pilosa exhibited higher competitiveness than C.odorata in the early stages of invasion,with stronger competitiveness in moderately or heavily invaded soil.These findings highlight the crucial role of soil legacy effects mediated by microorganisms in invasive alien plants invasion.Changes in soil microorganisms due to invasive alien plants are responsible for promoting the colonization and invasion of other alien plant species.
作者
代婉婷
倪馨营
赵彩云
DAI Wanting;NI Xinying;ZHAO Caiyun(Institute of Ecology,Chinese Research Academy of Environmental Sciences,Beijing 100012,China;School of Life Sciences,Lanzhou University,Lanzhou,Gansu 730000,Chin)
出处
《环境科学研究》
CAS
CSCD
北大核心
2024年第10期2278-2287,共10页
Research of Environmental Sciences
基金
国家重点研发计划项目(No.2016YFC1201100)。
关键词
土壤遗留效应
飞机草
鬼针草
入侵程度
入侵熔毁
相对竞争强度
soil legacy effects
Chromolaena odorata
Bidens pilosa
invasion degree
invasional meltdown
relative competition intensity
