摘要
【目的】探讨在Cd胁迫下蚯蚓对土壤Cd含量,豌豆各部位(根、茎、叶、果实)生长、Cd吸收及转移的影响,厘清蚯蚓在土壤—豌豆系统中对Cd动态分布的影响机制。【方法】采用盆栽试验,利用ICP-OES技术,以不添加蚯蚓为对照(CK),在不同浓度Cd处理后于第7、14、28、42、56天测定蚯蚓生物量及其体内Cd含量、土壤中Cd含量、豌豆植株(分为根、茎、叶和果实)鲜重及其Cd含量,分析添加蚯蚓对Cd污染农田修复治理效果及Cd在豌豆各部位的残留动态。【结果】添加蚯蚓处理降低土壤中全Cd含量,在35 mg/kg Cd处理下,除第7天外,添加蚯蚓组相比未添加蚯蚓组土壤中的Cd含量均显著降低(P<0.05);在70 mg/kg Cd处理下,除第7、28天外,添加蚯蚓组相比未添加蚯蚓组土壤中的Cd含量均显著降低(P<0.05),表明蚯蚓能吸收、富集重金属从而降低土壤中的Cd含量。同时,相比未添加蚯蚓组,添加蚯蚓组在第7~28天豌豆的Cd转移系数均降低,包括从根到茎、从茎到叶的转移;在第56天添加蚯蚓组相比未添加蚯蚓组叶到果实的Cd转移系数也降低,表明Cd更多地累积在豌豆根部,食用部分累积少。尤其是在70 mg/kg Cd处理条件下,与未添加蚯蚓的对照组相比,添加蚯蚓的处理组在第42天豌豆根部Cd含量降低14.22%,茎降低26.08%,在第56天果实Cd含量降低56.38%,表明蚯蚓对Cd转移的抑制作用显著,但在第42~56天,长期Cd胁迫对蚯蚓生存造成毒害,降低了蚯蚓对Cd耐受性。除此以外,蚯蚓的存在促进了豌豆生物量的增长,在35、70 mg/kg Cd处理条件下,添加蚯蚓显著增加了根、茎的生物量,其中在第14天茎部最高增幅达30.80%,添加蚯蚓提高了豌豆的抗逆性,有效缓解了Cd的毒害效应。【结论】添加蚯蚓可降低土壤中Cd含量,抑制Cd从土壤向豌豆根、茎、叶、果实转移,可降低豌豆Cd含量,减少Cd在豌豆可食用部分的积累,对农田土壤中的Cd污染具有一定的修复作用。
[Objective]The present paper aimed to investigate the effects of earthworms on soil cadmium(Cd)content,the growth and Cd absorption and transfer of various parts(roots,stems,leaves and fruits)of peas under Cd stress,and to clarify the mechanism by which earthworms affected the dynamic distribution of Cd in the soil-pea system.[Method]A pot experiment was conducted using ICP-OES technology.With no earthworm addition as the control(CK),Cd concentrations were measured at 7,14,28,42 and 56 days after different Cd treatments.The biomass of earthworms,their Cd content in the body,Cd content in the soil,and the fresh weight and Cd content of pea plants(divided into roots,stems,leaves and fruits)were determined.The effects of adding earthworms on the remediation and treatment of Cd-contaminated farmland and the residual dynamics of Cd in the various parts of peas were analyzed.[Result]The addition of earthworms reduced the total Cd content in the soil.At a 35 mg/kg Cd treatment,except on the 7th day,the Cd content in the soil of the earthworm-added group was significantly lower than that of the non-earthworm-added group(P<0.05);At a 70 mg/kg Cd treatment,except on the 7th and 28th days,the Cd content in the soil of the earthworm-added group was significantly lower than that of the non-earthworm-added group(P<0.05),indicating that earthworms could absorb and accumulate heavy metals,thereby reducing the Cd content in the soil.At the same time,compared with the non-earthworm-added group,the Cd transfer coefficients of peas in the earthworm-added group decreased from the 7th to the 28th day,including the transfer from roots to stems and from stems to leaves;On the 56th day,the Cd transfer coefficient from leaves to fruits in the earthworm-added group was also lower than that of the non-earthworm-added group,indicating that Cd accumulated more in the roots of peas and less in the edible parts.Especially under the 70 mg/kg Cd treatment condition,compared with the control group without earthworm addition,the Cd content in the roots of peas decreased by 14.22%on the 42nd day,and in the stems by 26.08%on the 42nd day.On the 56th day,the Cd content in the fruits decreased by 56.38%in the earthworm-added group compared with the non-earthworm-added group,indicating that the inhibitory effect of earthworms on Cd transfer was significant.However,from the 42nd to the 56th day,long-term Cd stress caused toxicity to earthworms and reduced their tolerance to Cd.In addition,the presence of earthworms promoted the growth of pea biomass.At 35 and 70 mg/kg Cd treatments,the addition of earthworms significantly increased the biomass of roots and stems.Among them,the stem biomass increased by 30.80%on the 14th day.The addition of earthworms improved the stress resistance of peas,effectively alleviating the toxic effect of Cd.[Conclusion]Adding earthworms can reduce the Cd content in the soil,inhibit the transfer of Cd from the soil to the roots,stems,leaves,and fruits of peas,reduce the Cd content in peas,and decrease the accumulation of Cd in the edible parts of peas.It has a certain remedial effect on Cd pollution in farmland soil.
作者
张冉
唐红红
王妙
孙仕仙
ZHANG Ran;TANG Hong-hong;WANG Miao;SUN Shi-xian(School of Ecology and Environment,Southwest Forestry University/Key Laboratory of Protection,Restoration and Ecological Services of Highland Wetlands in Yunnan Province,Kunming 650224,China;National Highland Wetland Research Centre,Kunming 650224,China)
出处
《西南农业学报》
北大核心
2025年第6期1287-1296,共10页
Southwest China Journal of Agricultural Sciences
基金
国家自然科学基金项目(42167057)
云南省高原湿地保护修复与生态服务重点实验室开放基金(202105AG070002)
“兴滇英才支持计划”项目。
关键词
蚯蚓
豌豆
CD污染
重金属含量
农田土壤修复
食品安全
Earthworms
Pea
Cadmium pollution
Heavy metal content
Farmland soil remediation
Food safety
