摘要
为探究铜(Cu)污染下施用生物炭对蚯蚓生长和Cu富集的影响机制,将赤子爱胜蚯蚓(Eisenia fetida)暴露在包含铜污染和不同热解温度(300℃和600℃)和施用比例(1%和3%)的水稻生物炭的人工土壤中,进行为期45 d的亚急性毒性试验.结果显示,Cu胁迫下,施用生物炭均不同程度抑制了蚯蚓的生长,促进了蚯蚓对Cu的富集,加剧了蚯蚓的氧化应激,导致蚯蚓SOD、CAT活性和MDA含量增加,形态学损伤加剧.且300℃生物炭处理下蚯蚓的Cu富集量相较于同一施用比例下600℃生物炭处理分别提高了3.13%和28.04%.同时,生物炭施用导致土壤水溶态Cu含量迅速增加.相关分析表明,Cu胁迫下,蚯蚓Cu富集量与培养前土壤水溶态Cu含量显著相关,而土壤水溶态Cu含量与DOC含量之间呈显著相关.因此,在蚯蚓培养前,300℃生物炭处理下土壤DOC含量和水溶态Cu含量均高于同一施用比例的600℃生物炭处理,可能是导致培养结束后前者处理中蚯蚓Cu富集量相对更高的重要原因.此外,蚯蚓Cu富集量、培养前期土壤水溶态Cu含量与土壤pH之间无明显相关性,故pH的改变可能不是影响Cu形态变化的决定因素.本研究结果表明Cu污染下,生物炭施用导致土壤DOC含量升高可能会增加Cu的生物有效性,不利于土壤动物的生长,对土壤生态系统造成负面影响.
To explore the effects and mechanisms of biochar on the growth of earthworms and Cu enrichment under Cu pollution,the earthworm species Eisenia fetida was exposed to artificial soil c ontaining Cu solution under different pyrolysis temperatures(300℃and 600℃)and application ratios(1%and 3%)of rice biochar.A 45-day subacute toxicity test of Cu and biochar on E.fetida was conducted.The results showed that the application of biochar inhibited the growth of E.fetida under Cu pollution.In addition,it significantly promoted Cu enrichment in E.fetida,exacerbated the oxidative stress of E.fetida,increased superoxide dismutase(SOD),catalase(CAT)activity,and malondialdehyde(MDA)content,and induced morphological damage in E.fetida.The Cu concentration in E.fetida under 300℃biochar treatment at 1%and 3%application rates increased by 3.13%and 28.04%,respectively,in comparison with the 600℃biochar treatment.Further,biochar application resulted in a rapid increase in water-soluble Cu content.Correlation analysis showed that the Cu concentration in E.fetida was significantly correlated with the soil water-soluble Cu content prior to earthworm culturing.The soil water-soluble Cu content was significantly correlated with soil dissolved organic carbon(DOC)content.The soil DOC content and water-soluble Cu content at 300℃biochar treatments at 1%and 3%application rates were higher than the 600℃biochar treatments before the culture of E.fetida.This may be an important reason for the higher Cu enrichment in E.fetida in the 300℃biochar treatments.In addition,no significant correlations were observed between Cu concentration in E.fetida,water-soluble Cu content,and soil pH.The change in soil pH caused by biochar application was possibly not the decisive factor affecting the morphological change of Cu.The results indicated that the increase in soil DOC content caused by biochar application may increase the bioavailability of Cu under Cu pollution,which is not conducive to the growth of soil animals and has a negative impact on the soil ecosystem.
作者
李莹
李小艳
周垂帆
LI Ying;LI Xiaoyan;ZHOU Chuifan(Institute for Agricultural Standard Testing Technology,Fujian Academy of Agricultural Sciences,Fuzhou 350003,China;Fujian Key Laboratory of Agro-products Qualitiy and Safety,Fuzhou 350003,China;College of Forestry,Fujian Agriculture and Forestry University,Fuzhou 350002,China;Key Laboratory of Soil and Water Conservation State Forestry and Grassland Administration,Southern Red Soil Region,Fuzhou 350002,China)
出处
《应用与环境生物学报》
CAS
CSCD
北大核心
2021年第5期1226-1232,共7页
Chinese Journal of Applied and Environmental Biology
基金
福建省自然科学基金面上项目(2020J01520)
国家自然科学基金面上项目(32071746)
福建农林大学林学高峰学科建设优秀青年培育工程项目(71201800727)资助。
关键词
铜污染
生物炭
人工土壤
抗氧化酶
可溶性有机碳
copper pollution
biochar
artificial soil
antioxidant enzyme
dissolved organic carbon
