摘要
高羊茅(Festuca arundinacea)作为抗逆性强、适应性广的禾本科植物,广泛应用于生态修复与护坡工程,但其在工程碎石土(松散贫瘠、微生物匮乏的隧道钻爆产物)中生长受限。研究表明,高羊茅根系通过分泌有机物质为微生物提供碳源并调节土壤酶活性,但碎石土的低粘结性与养分匮乏等限制因素仍严重影响植物的生长。植物-微生物协同修复是改善此类逆境的有效策略,其中根际促生菌(PGPR)如枯草芽孢杆菌(Bacillus subtilis)可通过分泌有机酸、解磷解钾及诱导抗逆性促进植物生长,而高羊茅根系分泌物作为碳源提高了微生物群落的稳定性,二者形成互惠关系。然而,现有研究多聚焦常规土壤环境,碎石土基质下两者的相关性尚不明确。本试验通过室内盆栽实验,选用高羊茅为植物材料,分别添加营养液和枯草芽孢杆菌进行处理,研究人工干预下碎石土养分、酶活力的变化对高羊茅生长状态的影响。结果表明:与对照组相比,营养液的引入提高了有机碳和铵态氮含量,但碎石土保水性差导致养分流失。枯草芽孢杆菌和高羊茅互作可改良碎石土,显著提升有机碳、速效磷、速效钾和硝态氮含量,促进养分积累。蔗糖酶和脲酶活性在两处理组中均不同程度提高,促进高羊茅生物量积累。蔗糖酶对根冠比与地下干重的贡献在枯草芽孢杆菌和养分处理组下均呈现不同程度的提高且显著优于对照组,而全磷、全钾对根冠比与地下干重的贡献仅在枯草芽孢杆菌处理组中显著增强。本研究可为改善高羊茅在碎石土中的不良长势提供可行性措施。
Festuca arundinacea,a resilient and widely adapted graminaceous plant,is widely used in ecological restoration and slope protection projects.However,its growth is limited in engineered gravel soil—a loose,infertile,and microbedeficient product of tunnel drilling and blasting.Studies have shown that the root system of F.arundinacea provides a carbon source for microorganisms and regulates soil enzymes by secreting organic substances.Nevertheless,limitations such as the low cohesion and nutrient deficiency of engineered gravel soils still severely restrict the plant growth.Plant-microbe synergistic remediation is an effective strategy to alleviate such adverse conditions.Among them,plant growth-promoting rhizobacteria(PGPR),such as Bacillus subtilis can promote plant growth by secreting organic acids,solubilizing phosphorus and potassium,and inducing stress resistance.Meanwhile,the root exudates of F.arundinacea act as carbon sources to enhance the stability of the microbial community,forming a reciprocal relationship between the F.arundinacea and Bacillus subtilis.However,most existing studies focus on conventional soil environments,and the correlation between the two in engineered gravel soil substrate remains unclear.This experiment conducts an indoor pot experiment,selecting F.arundinacea as the plant material.It treats the plants with nutrient solution and B.subtilis separately to investigate the effects of changes in nutrients and enzyme activities of engineered gravel soil on the growth status of F.arundinacea under artificial intervention.The results show that compared with the control group,the addition of nutrient solution increases the contents of organic carbon and ammonium nitrogen,but the poor water retention capacity of engineered gravel soil leads to nutrient loss.The interaction between B.subtilis and F.arundinacea improves engineered gravel soil,significantly increasing the contents of organic carbon,available phosphorus,available potassium,and nitrate nitrogen,thereby promoting nutrient accumulation.Sucrase and urease activities increase to varying degrees in both treatment groups,promoting the biomass accumulation of F.arundinacea.The contribution of sucrase to the root-shoot ratio and belowground dry weight increases to different degrees in both the B.subtilis and nutrient treatment groups,which is significantly superior to that in the control group.In contrast,the contribution of total phosphorus and total potassium to the root-shoot ratio and belowground dry weight is significantly enhanced only in the B.subtilis treatment group.This study provides feasible measures for improving the unfavorable growth performance of F.arundinacea in engineered gravel soil.
作者
白金鑫
詹登海
石立豪
胡芸菲
韩洪瑞
罗正宇
BAI Jin-xin;ZHAN Deng-hai;SHI Li-hao;HU Yun-fei;HAN Hong-rui;LUO Zheng-yu(School of Ecology and Environment/Chengdu University of Technology,Chengdu 610059,China;Key Laboratory of Synergistic Control and Joint Remediation of Soil and Water Pollution for National Environmental Protection,Chengdu 610059,China)
出处
《山东农业大学学报(自然科学版)》
北大核心
2026年第1期13-22,共10页
Journal of Shandong Agricultural University:Natural Science Edition
基金
西南诸河上游重大水电工程扰动区一体化边坡防护与生态修复技术(2024YFF1307800)。
关键词
碎石土
高羊茅
根际促生菌
酶活力
土壤养分
Gravel soil
Festuca arundinacea
plant growth-promoting rhizobacteria
enzyme activity
soil nutrients
