碱性液体肥对树仔菜-土壤重金属生物有效性及积累迁移的影响  

Effects of alkaline liquid fertilizer on bioavailability,accumulation and migration of heavy metals in Sauropus androgynus-soil

作　　者：范琼[1] 冯剑 邹冬梅[1] 酒元达 吴小芳[1] 苏初连 赵敏[1] FAN Qiong;FENG Jian;ZOU Dong-mei;JIU Yuan-da;WU Xiao-fang;SU Chu-lian;ZHAO Min(Analysis and Testing Center,Chinese Academy of Tropical Agricultural Sciences/Hainan Provincial Key Laboratory of Quality and Safety for Tropical Fruits and Vegetables/Key Laboratory of Quality and Safety Control for Subtropical Fruit and Vegetable,Ministry of Agriculture and Rural Affairs,Haikou,Hainan 571101,China)

机构地区：[1]中国热带农业科学院分析测试中心/海南省热带果蔬产品质量安全重点实验室/农业农村部亚热带果品蔬菜质量安全控制重点实验室,海南海口571101

出　　处：《南方农业学报》2022年第12期3336-3345,共10页Journal of Southern Agriculture

基　　金：海南省自然科学基金项目(320QN301);海南省热带果蔬产品质量安全重点实验室开放课题(KFKT2021001);五指山市生态科技特派员项目(WZSKTPXM2021006)。

摘　　要：【目的】评价海南地质高背景区树仔菜的质量安全性,并考察碱性液体肥对降低土壤中重金属有效性,以及降低树仔菜对土壤中重金属吸收的效果,为改善土壤环境和促进树仔菜安全生产提供参考依据。【方法】采用大田试验,分别施用碱性液体肥和复合肥,研究重金属铅(Pb)、铬(Cr)和砷(As)在树仔菜—土壤中的形态特征及迁移积累规律,考察碱性液体肥对树仔菜吸收积累迁移重金属的影响,并对土壤属性与重金属形态及树仔菜各部位重金属含量进行相关分析,明确影响重金属Pb、Cr、As在树仔菜—土壤系统中迁移积累的环境因子。【结果】与复合肥对照区相比,施用碱性液体肥提升土壤pH 1.25,其土壤有机质(OM)和阳离子交换量(CEC)分别提高9.1%和8.4%。Pb、Cr、As在树仔菜土壤中主要以残渣态存在,碱性液体肥分别降低Pb、Cr和As交换态75.5%、25.9%和0.8%,而复合肥提升Pb和Cr交换态36.8%和26.5%。施用碱性液体肥施用后树仔菜嫩梢中的Pb、Cr和As含量分别降低73.0%、59.4%和34.0%,而复合肥施用后树仔菜嫩梢的Pb含量显著增加39.3%(P<0.05,下同),Cr和As含量变化不显著(P>0.05)。树仔菜Pb和Cr在各部位积累规律为根>茎>叶>侧枝>嫩梢,迁移规律为TF2(茎→叶)≥TF1(根→茎)>TF3(叶→侧枝)>TF4(根→嫩梢),Pb、Cr和As主要积累在树仔菜根部,向叶部位运输的能力较强,向嫩梢运输的能力较弱。碱性液体肥施用后嫩梢的Pb富集系数下降50.0%,而施用复合肥的树仔菜所有部位Pb和Cr富集系数均显著升高。碱性液体肥试验区Pb、Cr和As的TF4分别显著下降73.3%、43.6%和46.9%,而复合肥对照区Pb的TF4显著升高30.0%,As的TF1显著升高11.0%。土壤pH、CEC和OM与树仔菜侧枝和嫩梢中重金属Cr、Pb、As含量呈显著或极显著(P<0.01)负相关。【结论】施用碱性液体肥是一种既能提供植株养分,又能降低重金属生物有效性,减少重金属在树仔菜【Objective】To evaluate quality and safety of Sauropus androgynus in the high geological background area of Hainan,and to investigate effects of alkaline liquid fertilizer on heavy metal reduction in the soil,reduce heavy metal accumulation of S.androgynus from soil,with an aim to provide theoretical basis for improving soil environment and pro-moting safe production of S.androgynus.【Method】A field experiment was carried out by using alkaline liquid fertilizer and compound fertilizer to determine heavy metal lead(Pb),chromium(Cr),arseic(As)speciation characteristics and migration regularity in S.androgynus-soil,and to investigate effects of alkaline liquid fertilizer on accumulation of migrated heavy metal in S.androgynus.Correlation analysis was operated to analyze relationship between soil property,heavy metal speciation and heavy metal content in parts of S.androgynus to determine the environmental factors affecting the migra-tion of heavy metals Pb,Cr,As from S.androgynus to soil.【Result】Compared with compound fertilizer treatment(CF),the soil organic matter(OM)and cation exchange capacity(CEC)in alkaline liquid fertilizer treatment(AF)increased by 9.1%and 8.4%,respectively.Pb,Cr and As mainly existed as residues in the soil.Alkaline liquid fertilizer reduced ex-changeable Pb,Cr and As by 75.5%,25.9%and 0.8%,respectively;while compound fertilizer increased exchangeable Pb and Cr by 36.8%and 26.5%,respectively.After applying alkaline liquid fertilizer,Pb,Cr and As in S.androgynus decreased by 73.0%,59.4%and 34.0%,respectively,while Pb in CF significantly increased by 39.3%(P<0.05,the same below),but the content of Cr and As did not change significantly(P>0.05).Pb and Cr accumulation in S.androgynus decreased by the order of root>stem>leaf>branch>edible branch,migration decreased in the order of TF2(stem→leaf)≥TF1(root→stem)>TF3(leaf→branch)>TF4(root→edible branch),and Pb,Cr and As were mainly accumulated in the roots,which could well migrate to leaves,but poorly to edible branch.Enrichment

关 键 词：碱性液体肥 树仔菜 重金属 生物有效性 

分 类 号：S147.5[农业科学—肥料学]