{"title":"Differential blocking effects of Fe0 nanoplates on rice accumulation of typical essential and non-essential heavy metal elements in paddy fields","authors":"Saiyong Zhu, Minjie Chen, Huiwang Dai, Saiqa Menhas, Jiang Xu, Daohui Lin","doi":"10.1039/d4en00258j","DOIUrl":null,"url":null,"abstract":"This study investigated how nanoscale zero-valent iron (nZVI) affects the transfer of essential and non-essential heavy metals (HMs) from soil to rice in two paddy fields with varying Cd, Cu, and Zn pollution levels. Rice plants were cultivated with conventional field managements. 100 mg kg-1 Fe0 nanoplates were injected in rhizosphere soil at pre-sowing (P0), tillering (T1), jointing (J2), flowering (F3), and grain-filling (GF4) stages, respectively. Among them, the GF4 treatment performed the best, decreasing rice grain contents of Cd, Cu, and Zn (by 66.4%, 20.0%, and 24.8%, respectively) to the required safe levels. This reduction was attributed to significant inhibitions (25.9–49.4% for Cd, 52.4–61.2% for Cu, and 30.0–47.8% for Zn) in the soil-to-root transfers of these metals. Interestingly, essential and non-essential HMs exhibited different transfer patterns under the GF4 treatment. The root-to-stem transfer of Cd was also significantly inhibited (by 29.3–39.8%, p<0.05) and its stem-to-grain transfer remained largely unchanged (p>0.05) under the GF4 treatment, while the root-to-stem transfers of Cu and Zn kept relatively constant (p>0.05) and their stem-to-grain transfers all increased (by 22.0–173.3%, p<0.05) as to fortify the essential trace elements in grain, causing the better performance of Fe0 nanoplates in Cd blocking. Additionally, the immobilization of soil HMs by Fe0 nanoplates persisted for approximately 60 days, contributing to the sustained efficacy of the GF4 treatment. These findings highlight the potential of nZVI, particularly applied at grain-filling stage, to effectively mitigate HMs accumulation in rice grains and improve crop safety in polluted environments.","PeriodicalId":73,"journal":{"name":"Environmental Science: Nano","volume":null,"pages":null},"PeriodicalIF":5.8000,"publicationDate":"2024-06-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"Environmental Science: Nano","FirstCategoryId":"6","ListUrlMain":"https://doi.org/10.1039/d4en00258j","RegionNum":2,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q1","JCRName":"CHEMISTRY, MULTIDISCIPLINARY","Score":null,"Total":0}
引用次数: 0
Abstract
This study investigated how nanoscale zero-valent iron (nZVI) affects the transfer of essential and non-essential heavy metals (HMs) from soil to rice in two paddy fields with varying Cd, Cu, and Zn pollution levels. Rice plants were cultivated with conventional field managements. 100 mg kg-1 Fe0 nanoplates were injected in rhizosphere soil at pre-sowing (P0), tillering (T1), jointing (J2), flowering (F3), and grain-filling (GF4) stages, respectively. Among them, the GF4 treatment performed the best, decreasing rice grain contents of Cd, Cu, and Zn (by 66.4%, 20.0%, and 24.8%, respectively) to the required safe levels. This reduction was attributed to significant inhibitions (25.9–49.4% for Cd, 52.4–61.2% for Cu, and 30.0–47.8% for Zn) in the soil-to-root transfers of these metals. Interestingly, essential and non-essential HMs exhibited different transfer patterns under the GF4 treatment. The root-to-stem transfer of Cd was also significantly inhibited (by 29.3–39.8%, p<0.05) and its stem-to-grain transfer remained largely unchanged (p>0.05) under the GF4 treatment, while the root-to-stem transfers of Cu and Zn kept relatively constant (p>0.05) and their stem-to-grain transfers all increased (by 22.0–173.3%, p<0.05) as to fortify the essential trace elements in grain, causing the better performance of Fe0 nanoplates in Cd blocking. Additionally, the immobilization of soil HMs by Fe0 nanoplates persisted for approximately 60 days, contributing to the sustained efficacy of the GF4 treatment. These findings highlight the potential of nZVI, particularly applied at grain-filling stage, to effectively mitigate HMs accumulation in rice grains and improve crop safety in polluted environments.
期刊介绍:
Environmental Science: Nano serves as a comprehensive and high-impact peer-reviewed source of information on the design and demonstration of engineered nanomaterials for environment-based applications. It also covers the interactions between engineered, natural, and incidental nanomaterials with biological and environmental systems. This scope includes, but is not limited to, the following topic areas:
Novel nanomaterial-based applications for water, air, soil, food, and energy sustainability
Nanomaterial interactions with biological systems and nanotoxicology
Environmental fate, reactivity, and transformations of nanoscale materials
Nanoscale processes in the environment
Sustainable nanotechnology including rational nanomaterial design, life cycle assessment, risk/benefit analysis