Low levels of arsenic and cadmium in rice grown in southern Florida Histosols - Impacts of water management and soil thickness
Low levels of arsenic and cadmium in rice grown in southern Florida Histosols - Impacts of water management and soil thickness
复制标题
佛罗里达州南部种植的水稻中砷和镉含量较低 Histosols - 水管理和土壤厚度的影响
DOI：
10.1016/j.scitotenv.2023.161712
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发表时间：
2023
影响因子：
9.8
通讯作者：
Seyfferth, Angelia L.
中科院分区：
文献类型：
--
作者：
Hu, Ruifang;Cooper, Jennifer A.;Daroub, Samira H.;Kerl, Carolin F.;Planer-Friedrich, Britta;Seyfferth, Angelia L.
在佛罗里达南部以甘蔗为主的大沼泽地农业区（EAA），水稻作为轮作作物种植。由于有机质含量高和排水时有机质快速氧化引起的地面沉降，该地区的组织土与其他用于种植水稻的矿质土壤不同。目前尚不清楚，如果这样的土壤构成的风险，砷（As）或镉（Cd）的移动和吸收到水稻籽粒。砷和镉都是水稻中的致癌微量元素，了解它们在土壤-植物中向全球重要主食水稻的转移是很重要的。在这里，中围盆栽研究进行了使用两个厚度的当地土壤，深（D，50厘米）和浅（S，25厘米），在三个水管理，传统的洪水（FL），低水位（LWT），干湿交替（AWD）。水稻生长成熟和植物水平的砷和镉进行了测定。无论何种处理，生长在这些佛罗里达组溶土中的水稻在抛光谷物中的镉浓度非常低（1.5-5.6 μg kg−1），抛光谷物中的总砷浓度（35-150 μg kg−1）和无机砷浓度（35-87 μg kg−1）相对较低，低于监管限值。水分管理（AWD < FL = LWT）及其与土壤厚度的互作效应（AWD-D ≤ AWD-S ≤ FL-D = LWT-S = LWT-D ≤ FL-S）显著影响籽粒As含量，各处理间差异高达62%。水分管理对籽粒Cd的影响显著（AWD > FL > LWT），土壤厚度对籽粒Cd的影响不显著。总之，即使水管理有更多的影响，水稻砷和镉比土壤厚度，低浓度的砷和镉在大米构成的健康风险不大。
Rice is planted as a rotation crop in the sugarcane-dominant Everglades Agricultural Area (EAA) in southern Florida. The Histosols in this area are unlike other mineral soils used to grow rice due to the high organic content and land subsidence caused by rapid oxidation of organic matter upon drainage. It remains unknown if such soils pose a risk of arsenic (As) or cadmium (Cd) mobilization and uptake into rice grain. Both As and Cd are carcinogenic trace elements of concern in rice, and it is important to understand their soil-plant transfer into rice, a staple food of global importance. Here, a mesocosm pot study was conducted using two thicknesses of local soil, deep (D, 50 cm) and shallow (S, 25 cm), under three water managements, conventional flooding (FL), low water table (LWT), and alternating wetting and drying (AWD). Rice was grown to maturity and plant levels of As and Cd were determined. Regardless of treatments, rice grown in these Florida Histolsols has very low Cd concentrations in polished grain (1.5–5.6 μg kg−1) and relatively low total As (35–150 μg kg−1) and inorganic As (35–87 μg kg−1) concentrations in polished grain, which are below regulatory limits. This may be due to the low soil As and Cd levels, high soil cation exchange capacity due to high soil organic matter content, and slightly alkaline soil pH. Grain As was significantly affected by water management (AWD < FL = LWT) and its interaction effect with soil thickness (AWD-D ≤ AWD-S ≤ FL-D = LWT-S = LWT-D ≤ FL-S), resulting in as much as 62 % difference among treatments. Grain Cd was significantly affected by water management (AWD > FL > LWT) without any soil thickness impact. In conclusion, even though water management has more of an impact on rice As and Cd than soil thickness, the low concentrations of As and Cd in rice pose little health risk for consumers.