摘要
为了优化李氏禾(Leersia hexandra Swartz)铬修复时的施氮效率,通过盆栽试验,研究了5种氮肥形态(硝酸钙、尿素、氯化铵、硝酸铵、硫酸铵)对李氏禾铬修复性能、生长指标和根系指标的影响。结果表明:与对照(不施氮肥)相比,施加的5种形态氮肥均促进了李氏禾生长,提高了根系活力,改变了根系形态特征,有利于提高李氏禾铬含量、铬累积量、富集系数和土壤铬去除率。施加硫酸铵的李氏禾生物量和根平均直径最大,分别为对照的5.54倍和1.51倍,其根系活力比对照增加108%;施加硝酸铵的李氏禾总根表面积和总根体积最大,分别为对照的2.17倍和1.99倍(P<0.05)。相关性分析结果表明,李氏禾的生物量、根平均直径、总根表面积、总根体积和根系活力均与土壤铬修复效率有关。其中,施加硫酸铵处理的富集系数和土壤铬去除率最高,分别为对照的1.45倍和5.56倍。研究表明,施加硫酸铵比其他氮肥形态更有利于提高李氏禾铬污染土壤修复效率。
In order to optimize the nitrogen application efficiency of Leersia hexandra Swartz in soil chromium(Cr)remediation,the effects of five nitrogen fertilizer forms(calcium nitrate,urea,ammonium chloride,ammonium nitrate and ammonium sulfate)on Cr remediation efficiency,growth index,and root index of L.hexandra were assessed in pot experiments.The results showed that,compared with the control,the five nitrogen fertilizer forms promoted the growth and the root activity of L.hexandra and changed its root morphological characteristics;these changes improved Cr content,rate of Cr accumulation,bioconcentration factor(BCF),and the soil Cr removal rate of itself.The biomass and average root diameter of L.hexandra were greatest under ammonium sulfate treatment,with values 5.54 times and 1.51 times of the control,respectively,and the root activity increased by 108%compared with the control.The total root surface area and total root volume were greatest under ammonium nitrate,with values that were 2.17 times and 1.99 times of the control,respectively(P<0.05).The results of correlation analysis showed that the biomass,average root diameter,total root surface area,total root volume,and root activity of L.hexandra were related to the efficiency of soil Cr remediation.Among these factors,the BCF and soil Cr removal rate were highest under ammonium sulfate treatment,with values that were 1.45 times and 5.56 times of the control,respectively.Therefore,the application of ammonium sulfate is more conducive to improve the remediation efficiency of Cr-contaminated soil than other forms of nitrogen fertilizer.
作者
陈诗奇
刘杰
蒋旭升
韩庆坤
王路洋
CHEN Shiqi;LIU Jie;JIANG Xusheng;HAN Qingkun;WANG Luyang(Guangxi Key Laboratory of Environmental Pollution Control Theory and Technology,Guilin University of Technology,Guilin 541004,China)
出处
《农业环境科学学报》
CAS
CSCD
北大核心
2024年第6期1250-1259,共10页
Journal of Agro-Environment Science
基金
国家自然科学基金项目(32271700)
广西自然科学基金重点项目(2020GXNSFDA297018)。
关键词
氮肥形态
铬污染
李氏禾
根系特征
修复效率
nitrogen fertilizer forms
Cr pollution
Leersia hexandra Swartz
root characteristics
remediation efficiency
