College of Resources, Hunan Agricultural University, Changsha, 410128, China.
College of Landscape Architecture and Art Design, Hunan Agricultural University, Changsha, 410128, China.
Environ Pollut. 2024 Oct 15;359:124552. doi: 10.1016/j.envpol.2024.124552. Epub 2024 Jul 14.
Selenium (Se) deficiency is a major global health issue. Given that the Dongting Lake region is a significant agricultural production area in China, its soil and geographical properties have a marked influence on Se accumulation in rice. Investigating these factors and their importance can provide technical guidance for the production of Se-rich rice locally and in other similar regions worldwide. Such studies can foster Se-enriched agricultural practices on a global scale, contributing to improved human health and environmental quality. Therefore, in this study, we investigated 15,403 paddy soil samples and their corresponding rice grains from the Dongting Lake area, by analyzing their Se content, spatial distribution, and bioaccumulation factor (BCF). The effects of parent materials, soil characteristics (physicochemical), and geographical factors on Se content in soil, rice grains, and BCF were also assessed. We found that the average Se content in the paddy soil of the Dongting Lake area was 0.43 mg/kg, which was 1.48 folds higher than the background Se content (0.29 mg/kg) in Chinese soil. The average Se content in rice grains was 0.059 mg/kg, surpassing the Chinese standard for Se-rich rice (0.04 mg/kg). Se distribution in the paddy soil and rice were the highest in the western and central regions and lowest in the eastern region. Se-enriched rice and Se-enriched rice fields are widely distributed in Dongting Lake area. Seven parent materials significantly influenced soil Se and BCF. Correlation analysis revealed positive correlations between soil Se and soil organic matter (SOM), zinc, altitude, and mean annual precipitation. BCF was positively correlated with pH and mean annual temperature. The Random Forest model highlighted that SOM played a pivotal role in soil Se enrichment, being the most influential factor for both soil and rice enrichment (RR type), whereas pH exerted the most significant influence on soil enrichment without rice enrichment (RN type).
硒（Se）缺乏是一个全球性的主要健康问题。鉴于洞庭湖地区是中国重要的农业生产区，其土壤和地理特性对水稻中硒的积累有显著影响。研究这些因素及其重要性，可以为当地和全球其他类似地区生产富硒水稻提供技术指导。这些研究可以在全球范围内促进富硒农业实践，有助于改善人类健康和环境质量。因此，本研究通过分析洞庭湖地区 15403 个稻田土壤样品及其相应的水稻籽粒中的硒含量、空间分布和生物富集因子（BCF），对其进行了调查。还评估了母质、土壤特性（理化性质）和地理因素对土壤、水稻籽粒和 BCF 中硒含量的影响。我们发现，洞庭湖地区稻田土壤的平均硒含量为 0.43mg/kg，是中国土壤背景硒含量（0.29mg/kg）的 1.48 倍。水稻籽粒中的平均硒含量为 0.059mg/kg，超过了中国富硒水稻的标准（0.04mg/kg）。稻田土壤和水稻中的硒分布在西部地区和中部地区最高，在东部地区最低。富硒水稻和富硒稻田在洞庭湖地区广泛分布。七种母质对土壤硒和 BCF 有显著影响。相关分析表明，土壤硒与土壤有机质（SOM）、锌、海拔和年平均降水量呈正相关。BCF 与 pH 和年平均温度呈正相关。随机森林模型突出表明，SOM 在土壤硒富集中起着关键作用，是土壤和水稻富集的最具影响力的因素（RR 型），而 pH 对土壤富集而无水稻富集的影响最大（RN 型）。
