摘要
植物入侵对全球生态系统造成了严重威胁,土壤养分条件(养分水平和养分异质性)对外来植物的成功入侵有重要影响。为了探讨土壤养分条件对入侵植物与同属本地植物生长的影响,本研究以入侵植物南美蟛蜞菊(Wedelia trilobata)和同属本地种蟛蜞菊(W.chinensis)为试验材料开展了温室控制实验。实验设置了低、中、高及异质性养分条件下的单种和混种两种种植方式,测定了每种植物总生物量,根、茎、叶生物量及分节数、根冠比等指标,并分析了土壤养分对二者生长的影响。结果表明:土壤养分水平增加显著促进了南美蟛蜞菊和本地蟛蜞菊的生长;土壤养分异质性显著增加了南美蟛蜞菊根生物量和根冠比,显著增加了本地蟛蜞菊的总生物量、根生物量和茎生物量;土壤养分水平和养分异质性对南美蟛蜞菊和本地蟛蜞菊的竞争响应均无显著影响;在土壤养分较高或较低时南美蟛蜞菊更容易入侵成功;在异质养分环境中,当南美蟛蜞菊生长处于高养斑块时更容易入侵成功。
Plant invasion seriously threatens the structure and function of ecosystems, and soil nutrient availability （soil nutrient amount and spatial heterogeneity） plays a key role in the suc- cessful invasion of introduced species. To explore the effect of soil nutrients on the growth of inva- sire and native species, a greenhouse experiment was conducted with the invasive species （ Wede- lia trilobata） and its native congener （ W. chinensis） under monoculture and mixture in homoge- neous soil environments of three nutrient levels and one heterogeneous environment. Growth meas- ures （e.g., total biomass, root mass, stem mass, leaf mass, number of nodes, and root to shoot mass ratio were measured and the effect of soil nutrients was analyzed. Increased soil nutrient lev- els significantly promoted the growth of the two species. Soil nutrient heterogeneity improved the root mass and root to shoot mass ratio of IV. trilobata, as well as the total biomass, root mass, and stem mass of IV. chirtensis. Soil nutrient level or nutrient heterogeneity had no significant im- pact on competition response of IV. trilobata. We concluded that compared to its congener, IV. tri- lobata had a higher probability to invade successfully in the higher homogeneous soil nutrient en- vironment, and also in high-nutrient patches of the heterogeneous soil nutrient environment.
出处
《生态学杂志》
CAS
CSCD
北大核心
2017年第4期962-970,共9页
Chinese Journal of Ecology
基金
国家自然科学基金项目(41571084)资助
关键词
土壤养分
种间关系
异质性
入侵植物
soil nutrient
interspecific relationship
heterogeneity
invasive plant.
