Cheng Xiaomeng, Zhang Li, Zhao Chen, Peng Min, Qin Yuanli, Han Wei, Zhang Fugui, Zeng Daoming, Yang Fan
Institute of Geophysical and Geochemical Exploration, Chinese Academy of Geological Sciences, No. 84, Jinguang Road, Langfang, 065000, China.
Geochemical Research Center of Soil Quality, China Geological Survey, Langfang, 065000, China.
Environ Geochem Health. 2025 Jan 4;47(2):39. doi: 10.1007/s10653-024-02349-w.
Selenium (Se) is an essential element for humans, playing a critical role in the functioning of the immune system. The global prevalence of dietary Se deficiency is a significant public health concern, largely attributed to the low levels of Se present in crops. The sufficient Se in plants and humans is determined by the presence of stable Se sources in the soil. The Leizhou Peninsula is an important agricultural region in China, but the concentration and spatial distribution of Se in its soils remain unclear. To address this issue, we analyzed Se concentration data from 3333 soil samples collected at the depth of 0-20 cm from the Leizhou Peninsula, covering an area of 13,225 km. The results indicate that the mean soil Se concentration was 0.50 mg kg, with Se-enriched soils being widely distributed. This provides prospects for the development of Se-enriched crops. Using random forest (RF) modeling and correlation analysis, the clay minerals (Fe-Al oxides), chemical index of alteration (CIA), and soil organic carbon (SOC) have been identified as the principal determinants of Se distribution in soil. During the weathering processes of the basalts, Fe-Al oxides serve as a crucial factor in Se accumulation in the red soils. Furthermore, the tropical climate further contributes to increasing the degree of weathering and the proportion of clay minerals and SOC in the soil. Atmospheric deposition derived from marine and precipitation is another important factor that promotes Se flux into soils. In conclusion, the distribution pattern of Se is jointly determined by the weathering process of basalt and climatic conditions. The results of the geographically weighted regression (GWR) analysis revealed that SOC, AlO, TFeO and CIA change spatially and exhibit a spatial non-stationarity relationship with Se. This study offers a theoretical foundation and practical guidance for the sustainable development of Se-enriched agriculture and similar climate settings worldwide.
硒（Se）是人体必需的元素，在免疫系统功能中发挥着关键作用。全球膳食硒缺乏的普遍情况是一个重大的公共卫生问题，这在很大程度上归因于作物中硒含量较低。植物和人体中充足的硒取决于土壤中稳定硒源的存在。雷州半岛是中国重要的农业地区，但其土壤中硒的含量和空间分布仍不清楚。为解决这一问题，我们分析了从雷州半岛采集的3333个深度为0至20厘米的土壤样本的硒含量数据，样本覆盖面积为13225平方公里。结果表明，土壤硒平均含量为0.50毫克/千克，富硒土壤广泛分布。这为富硒作物的发展提供了前景。通过随机森林（RF）建模和相关分析，已确定粘土矿物（铁铝氧化物）、化学蚀变指数（CIA）和土壤有机碳（SOC）是土壤中硒分布的主要决定因素。在玄武岩的风化过程中，铁铝氧化物是红壤中硒积累的关键因素。此外，热带气候进一步促使风化程度增加以及土壤中粘土矿物和SOC比例提高。源自海洋和降水的大气沉降是促进硒流入土壤的另一个重要因素。总之，硒的分布模式是由玄武岩的风化过程和气候条件共同决定的。地理加权回归（GWR）分析结果表明，SOC、AlO、TFeO和CIA在空间上发生变化，并且与硒呈现出空间非平稳关系。本研究为富硒农业的可持续发展以及全球类似气候环境提供了理论基础和实践指导。
