Page 67 - 《广西植物》2022年第12期
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12 期 韦春强等: 养分增加提高大狼耙草入侵种群的生长和竞争能力 2 0 5 7
B. biternata under three nutrient levels. The results were as follows: (1) When grown alone under high nutrientꎬ
B. frondosa had significantly higher values for plant heightꎬ branch number and total biomass compared with those grown
under low nutrient. The reproductive ratios of all the populations under low nutrient were significantly greater than those
under high nutrient except for Jiangsu Population. When grown with four populations togetherꎬ the competitive responses
of the growth parameters of each population of B. frondosa under high nutrient were significantly lower than those under
low nutrientꎬ indicating that this invasive weed was suppressed less under high nutrient compared with that under low
nutrient conditions. (2) Under all nutrient conditionsꎬ Guangxi and Jiangxi populations significantly grew higher and had
a greater total biomass than Hebei Population. Guangxi Population had the highest number of branches among the four
populations when grown at lowꎬ medium and high nutrients [(12 ± 0. 86)ꎬ ( 16. 83 ± 0. 95) and ( 21. 83 ± 1. 14)ꎬ
respectively]. The reproduction ratios of Hebei Population grown under low and high nutrients [(47.33±3.29)% and
(25.74 ± 2. 82)%ꎬ respectively] were significantly greater than those of Guangxi Population when grown under
comparable conditions [(30.92±1.78)% and (19.77±1.22)%ꎬ respectively]. In additionꎬ the competitive response of
total biomass were significantly greater for Hebei Population (-0.51±0.04) than for Guangxi Population (-0.35±0.06)
under medium nutrient. The competitive response of reproductive biomass of Hebei Population (-0.46±0.03) was also
significantly greater than that of Guangxi Population ( -0.28±0.07) under medium nutrient. Our results indicate that
nutrient addition can enhance the growth and competitive ability of B. frondosaꎬ there are variations in the growth and
competitive response among the introduced populationsꎬ and increasing nutrient and gene flow among populations may
enhance the potential risks of invasion by B. frondosaꎬ the results will help to predict the invasion risk of alien plants.
Key words: Bidens frondosaꎬ invasive populationꎬ growthꎬ competitive responseꎬ nutrient
由于人类活动ꎬ许多外来植物被引入到新的分 环境的可塑性响应可能存在差异ꎬ一旦不同种群
布区ꎬ其中有些种类已成为入侵植物ꎬ与本地植物 间发生基因流ꎬ会增加遗传多样性ꎬ使入侵植物进
竞争ꎬ降低了本地植物多样性(Powell et al.ꎬ 2011ꎻ 化出更高的可塑性ꎬ入侵更多样化的生境和群落
Power & Vilasꎬ 2020)ꎮ 了解外来植物的入侵性及 ( Richards et al.ꎬ 2006ꎻ Lavergne & Molofskuꎬ
其影响因素对于预测外来植物的入侵风险和管理 2007)ꎬ提高入侵风险ꎮ 入侵植物对本地植物的竞
外来入侵植物具有重要作用ꎮ 人类活动如施肥、排 争能力在不同种群间也会不同( He et al.ꎬ 2012)ꎮ
污等使生境中的养分增加ꎬ影响入侵植物和本地植 了解不同种群间对环境变化的响应是否有差异ꎬ
物的生长、繁殖和竞争(Zhang et al.ꎬ 2017ꎻ Wan et 可为采取措施阻止入侵植物进化出更高的入侵性
al.ꎬ 2019ꎻ 王亚等ꎬ 2021)ꎬ最终影响入侵植物是否 提供依据(Droste et al.ꎬ 2010)ꎮ
成功入侵(Huang et al.ꎬ 2018)ꎮ 例如ꎬ土壤氮养分 大 狼 耙 草 ( Bidens frondosa ) 隶 属 菊 科
增加提高斑点矢车菊( Centausea stoebe)、粗毛牛膝 (Compositae)ꎬ原产北美ꎬ近 10 多年在我国分布范
菊 ( Galinsoga quadriradiata) 和 加 拿 大 一 枝 黄 花 围不断扩大ꎬ在河北、河南、安徽、北京、广东、广西
(Solidago canadensis)等对本地植物的竞争能力(He 等 21 个省区有分布( 马金双ꎬ 2013)ꎮ 该入侵植
et al.ꎬ 2012ꎻ Liu et al.ꎬ 2018ꎻ Wan et al.ꎬ 2019)ꎬ促 物具有花序生物量分配较高( 周兵等ꎬ 2012)、化
进其成功入侵ꎮ 但是ꎬ也有研究发现土壤养分增加 感作用强( 闫小红等ꎬ 2012)、适宜温度下异型瘦
降低入侵植物香菇草( Hydrocotyle vulgaris) 的竞争 果萌发率高( 周超群等ꎬ 2015)、繁殖能力强( Yan
和提高本地群落的抗入侵性(Liu et al.ꎬ 2017)ꎮ 因 et al.ꎬ 2016)、竞争能力强( Pan et al.ꎬ 2016) 和表
此ꎬ了解养分增加对不同入侵植物生长和竞争的影 型可塑性较高( Wei et al.ꎬ 2017) 等入侵性相关特
响有助于预测入侵植物的入侵风险ꎮ 征ꎮ 金盏银盘(B. biternata)为本地杂草ꎬ与大狼耙
目前ꎬ土壤养分增加对入侵植物的影响ꎬ大多 草同属ꎬ有时和大狼耙草伴生ꎬ二者常分布于耕
集中于对入侵植物与本地植物之间生长和竞争的 地、弃耕地、路边和稻田边等人为干扰的具有不同
比较或入侵种群与原产地种群间的比较(He et alꎬ 养分的生境中( Pan et al.ꎬ 2016)ꎮ 近缘植物对资
2012ꎻ Liao et al.ꎬ 2013ꎻ Wan et alꎬ 2019)ꎬ较少关 源的需求相似ꎬ它们之间往往竞争较大( Balestri et
注不同入侵种群间是否有差异ꎮ 不同入侵种群对 al.ꎬ 2018)ꎮ 目前ꎬ养分增加对大狼耙草入侵种群