宁夏长山头富硒区土壤硒地球化学特征研究

本文对宁夏长山头典型富硒区土壤Se含量特征及玉米籽实Se含量影响因素进行了系统研究,发现长山头地区土壤硒背景含量为0.25 mg/kg,主要的富硒土壤类型为新积土,其成土母质为山前洪流携带的碎屑物。进一步的研究表明,土壤中硒含量与p H呈负相关关系,而与有机碳、TFe_2O_3及Mn呈正相关关系。与土壤环境相反,玉米籽实中硒的含量与p H成正相关关系,而与有机碳、TFe_2O_3及Mn呈负相关关系。这说明这些指标对硒在土壤-植物系统中的地球化学行为具有显著影响作用。此外,土壤中全量硒的增加对植物的吸收率并没有显著的促进作用。

Geochemical Characteristics of Soil Selenium in Selenium-rich Area in Changshantou, Ningxia Province, China

This paper systematically studied the main influencing factors on selenium in soil and maize. Results show that the background value of selenium is 0.25 mg/kg.The main selenium-rich soil is alluvial soils, whose parent materials is clastics carried by the mountain torrent. Further studies show that the Se content in soil is negatively correlated with pH, but positively correlated with organic matter, TFe₂O₃ and Mn. On the contrary, the content of selenium in maize is positively correlated with pH, but negatively correlated with organic matter, TFe₂O₃ and Mn. The paper indicates that the factors above-mentioned have a significant effect on the geochemical behavior of selenium in soil-plant system. In addition, Se content in soils has no marked impact on absorption rates of plants.