摘要
基于黄土高原生态屏障区土壤退化治理需求,研究黄土高原典型草本植物对纳米二氧化硅的响应机制,为纳米二氧化硅应用于黄土高原土壤修复提供理论依据,试验以典型草本植物紫花苜蓿和高羊茅为研究对象,通过梯度浓度纳米二氧化硅添加试验[0(CK)、0.2%、0.8%、2.0%],系统揭示纳米材料对植物根系形态发育及生物量的调控作用,采用根系形态解析与熵权综合评价方法,量化不同处理下根系参数的响应。结果显示,0.8%纳米二氧化硅浓度处理对两物种均产生显著促生效应,苜蓿总根长和根体积较不添加纳米二氧化硅处理提升61.5%、26.7%,高羊茅根系数量、根系体积增幅达113.9%、86.6%;而2.0%浓度处理引发显著抑制作用,两物种根系形态指标及生物量均发生不同程度的降低。高羊茅表现出更强的浓度敏感性,0.8%处理下其根体积增益较紫花苜蓿高60个百分点,但在2.0%处理时鲜重降幅(27.3%)为紫花苜蓿(13.6%)的2倍,且根系直径下降28.2%,而紫花苜蓿仅下降15.9%。机制解析表明苜蓿通过侧根系统冗余化增强抗逆性,而高羊茅主根延伸易受纳米颗粒物理堵塞影响。熵权模型综合评价显示0.8%浓度处理下两物种综合得分均达理论最大值(1.00),证实该浓度具有最优根系改良效益。
Based on the soil remediation needs in the ecological barrier zone of the Loess Plateau,this study investigated the response mechanism of selected typical herbaceous plants to nano-SiO_(2),providing a theoretical basis for the application of nano-SiO_(2) in soil restoration in the Loess Plateau.Two typical herbaceous plants-alfalfa(Medicago sativa)and tall fescue(Festuca arundinacea)-were used as research subjects,a gradient addition experiment with nano-SiO_(2) concentrations of 0(CK),0.2%,0.8%,and 2.0%was conducted to systematically reveal the regulatory effects of nanomaterials on root morphological development and biomass.Root morphological analysis and entropy-weighted comprehensive evaluation were employed to quantify responses of root parameters under different treatments.Results showed that the 0.8%concentration significantly enhanced growth in both species.Alfalfa exhibited 61.5%and 26.7%increases in total root length and root volume versus the control,while tall fescue showed 113.9%and 86.6%gains in root number and volume.Conversely,the 2%treatment caused significant inhibition,reducing root morphological indices and biomass across both species.Tall fescue demonstrated greater sensitivity to concentration changes,its root volume gain at 0.8%treatment exceeded alfalfa's by 60 percentage points,but its fresh weight reduction at 2%treatment(27.3%)was twice that of alfalfa(13.6%),and root diameter decreased by 28.2%in tall fescue,versus a milder reduction of 15.9%in alfalfa.Mechanistic analysis revealed alfalfa's enhanced stress resistance through lateral root redundancy,while tall fescue's primary root elongation was more susceptible to physical blockage by nanoparticles.The entropy-weighted model confirmed that both species achieved theoretical maximum comprehensive scores(1.00)under 0.8%treatment,validating that this concentration offers the optimal root improvement benefit.
作者
卓玛草
苟恩泽
孔冉
李广
ZHUOMA Cao;GOU Enze;KONG Ran;LI Guang(College of Geology and Jewelry,Lanzhou Resources and Environment Voc-tech University,Lanzhou Gansu 730021,China;College of Forestry,Gansu Agricultural University,Lanzhou Gansu 730070,China;Hexi University,Zhangye Gansu 734000,China)
出处
《寒旱农业科学》
2025年第8期734-740,共7页
Journal of Cold-Arid Agricultural Sciences
基金
甘肃省科技计划自然科学基金项目(25JRRA75)
兰州资源环境职业技术大学校级科研项目(X2024A-06)
甘肃省高校教师创新基金项目(2025A-298)。
