道路类型对南昌樟树铅含量及地下丛枝菌根真菌影响

Effects of Road Types on the Lead Content of Avenue Cinnamomum camphora and Underground Arbuscular Mycorrhiza Fungi in Nanchang

该文为探究道路土壤铅污染对行道树和土壤丛枝菌根(arbuscular mycorrhiza,AM)真菌的影响,在南昌市选择了6条行道树为樟树的不同类型道路,测定分析了土壤-樟树铅含量及AM真菌群落特征。结果表明,不同类型的道路上土壤铅含量存在显著差异,快速路和主干路的铅含量高于支路,车流量是重要驱动因素。樟树根、茎、叶、果的平均铅含量分别是0.41、1.13、1.43、0.53 mg/kg。主干路上樟树体内铅含量整体较高,支路上樟树铅含量相对较低,土壤铅含量与樟树根系铅含量显著正相关。AM真菌的根系侵染率、孢子密度和物种丰富度在不同类型道路间有差异但规律性不明显。6条道路样地土壤中共鉴定出AM真菌8属20种,无梗囊霉属为优势属,各样地菌种数在10~15种之间,铅污染显著影响了土壤AM真菌孢子密度。综上所述,交通是导致道路土壤铅积累的重要因素,进而造成行道樟树对铅的吸收,同时土壤AM真菌也受到铅污染的一定影响。因此,科学治理和修复土壤铅污染对生态环境保护和人类健康有重要意义。

In order to explore the effects of lead pollution in road soil on avenue trees and soil arbuscular mycorrhiza(AM)fungi,six types of roads with avenue trees as camphor tree(Cinnamomum camphora)were selected in Nanchang City,and the lead content of soil and camphor tree and the characteristics of AM fungi community were determined and analyzed.The results showed that there were significant differences in soil lead content among different types of roads.The lead content of expressway and main roads was higher than that of branch roads,and traffic flow was an important driving factor.The average lead content in the roots,stems,leaves and fruits of camphor tree was 0.41,1.13,1.43 and 0.53 mg/kg,respectively.The lead content in the camphor tree on the main roads was generally high,and the lead content in the camphor tree on the branch roads was relatively low.There was a significant positive correlation between soil lead content and lead content in the root of cam-phor tree.The root colonization rate,spore density,and species richness of AM fungi showed variations among different road types,although the patterns were not clearly evident.A total of 20 species of AM fungi belonging to 8 genera were identi-fied in the soil of six road plots.Acaulospora was the dominant genus,and the number of species in each plot was between 10 and 15.Lead contamination significantly affected the spore density of soil AM fungi.In summary,traffic was an important factor leading to the accumulation of lead in roadsoil,which in turn caused the absorption of lead by avenue camphor trees.At the same time,soil AM fungi were also affected by lead pollution.Scientific management and remediation of soil lead pol-lution is of great significance to ecological environment protection and human health.