文献类型： 外文期刊

作者： Fan, Qiong ¹ ; Jiu, Yuanda ¹ ; Zou, Dongmei ¹ ; Feng, Jian ¹ ; Zhao, Min ¹ ; Zhang, Qun ¹ ; Lv, Daizhu ¹ ; Song, Jia ¹ ; Xu, Zhi ¹ ; Ye, Haihui ¹ ;

作者机构： 1.Chinese Acad Trop Agr Sci, Testing & Anal Ctr, Haikou 571101, Peoples R China

2.Hainan Prov Key Lab Qual & Safety Trop Fruits & Ve, Haikou 571101, Peoples R China

3.Minist Agr & Rural Affairs, Key Lab Qual & Safety Control Subtrop Fruit & Vege, Haikou 571101, Peoples R China

关键词： Sauropus androgynus; Alkaline humic acid fertilizer; Heavy metal accumulation; Heavy metal translocation

期刊名称：ECOTOXICOLOGY AND ENVIRONMENTAL SAFETY （ 影响因子：6.8； 五年影响因子：6.9 ）

ISSN： 0147-6513

年卷期： 2023 年 268 卷

页码：

收录情况： SCI

摘要： Humic acids (HA) are a popular soil additive to reduce metal availability, but they have the drawbacks of reduced effectiveness over time and a significant reduction in soil pH. An alkaline humic acid fertilizer (AHAF) combining alkaline additives with HA was developed to overcome such drawbacks. A field experiment was conducted to investigate the effects of different AHAF application rates on the physicochemical properties, bioavailability, accumulation, and translocation of Cd and Zn heavy metals in Sauropus androgynus grown in acidic soil. Based on our results, the 100AF (100% AHAF) treatment significantly increased soil pH, cation exchange capacity (CEC), and organic matter content (OM) after one year of application. Compared with the control treatment (CK), the application of different rates of AHAF resulted in a 37.1-40.3% decrease in soil exchangeable Cd fractions (Exc-Cd) and an increase in the humic acid-bound Cd fractions (HA-Cd) Fe- and Mnoxide-bound Cd fractions (OX-Cd), and organic matter-bound Cd fractions (OM-Cd) by 9.5-64.6%, 24.8-45.1%, and 158.8-191.2%, respectively (P < 0.05). The different AHAF treatments decreased the Res-Zn, Exc-Zn, and OM-Zn fractions by 69.6-73.0%, 7.4-23.9%, and 18.1-23.2%, respectively (P < 0.05), and increased the HA-Zn fraction by 8.4-28.1%. In the control treatment, the bioconcentration factors (BCFs) for Cd and Zn in different S. androgynus plant organs were in the following order: (Cd) Leaves > Stems > Branches > Roots > Edible branches; (Zn) Roots > Stems > Leaves > Branches > Edible branches. The transfer factors (TFs) of Cd and Zn in S. androgynus were classified as follows: TF2 > TF1 > TF3 > TF4. Thus, S. androgynus stems, and roots had a strong ability to transport Cd and Zn to the leaves. Compared with CK, the 100AF treatment significantly increased the BCFs for Zn in all plant parts (except BCFedible branches). In contrast, it significantly decreased all BCFs and TFs for Cd and the TF4 for Zn, effectively reducing Cd and Zn accumulation in the edible branches of S. androgynus. Soil pH, CEC, OM, and HA-M fraction were highly and significantly negatively correlated with Cd and Zn content in edible branches (P < 0.001). Stepwise multiple linear regression analysis revealed that the soil HA-M fraction was the key contributing factor for Zn accumulation and translocation in S. androgynus. Moreover, based on our findings, the absorption, uptake, and translocation of Cd and Zn were mainly determined by metal speciation and the pH in the soil. Moreover, the competitive antagonistic mechanisms between Zn and Cd absorption also affected their accumulation in S. androgynus. Thus, AHAF can be used as a soil amendment to sustainably improve acidic soils and effectively reduce Cd and Zn accumulation in edible branches of S. androgynus.