云南耕地土壤硒含量空间分布及其影响因素研究

为了解云南耕地土壤硒含量状况,采集了640个云南代表性耕地表层土壤样品,对土壤硒含量空间分布特征及其影响因素进行研究。结果表明:(1)云南省耕地土壤硒总量变幅在0.05～7.12 mg/kg,平均含量为0.51 mg/kg,达到富硒水平;(2)不同成土母质发育的土壤硒含量差异较大,基型结晶盐类的玄武岩等发育的土壤硒含量最高,平均为0.77 mg/kg;(3)土壤类型对硒的含量影响明显,其中棕壤硒含量平均为1.24mg/kg,显著高于其他土壤类型,石灰(岩)土硒含量最低仅为0.21mg/kg;从行政区看位于滇东的曲靖市和昭通市土壤硒平均含量明显高于其他州市;(4)相关分析表明,土壤硒含量与土壤p H之间的相关性均没有达到显著水平;而土壤硒含量与土壤有机质呈极显著的正相关性(r=0.110,P 0.001),说明有机质影响土壤硒的含量。

Spatial Distribution of Se Content and Its Influencing Factors in Cultivated Topsoil in Yunnan

Selenium(Se) is an indispensable trace element in the human body. Selenium content in soil directly affects selenium intake in the food chain. Whether Se deficiency in Yunnan soil on the southwestern of China was inconclusive. A systematic study on the spatial distribution characteristics and influencing factors of Se in cultivated soil in Yunnan was still lacking. This study collected 640 cultivated surface soil samples in Yunnan. The distribution characteristics of soil Se content in Yunnan Province and its influencing factors were studied. The results showed that the total amount of Se in the surface soil of Yunnan Province ranged from 0.05 to 7.12 mg/kg, with an average content of 0.51 mg/kg, reaching a Se-rich level. Differences in soil Se content between different parent materials. The Se content of soils such as basic crystalline salt basalts was the highest, with an average of 0.77 mg/kg. Soil type had a significant effect on Se content. The Se content of brown soil was significantly higher, with an average of 1.24 mg/kg. The lowest was 0.21 mg/kg in lime soil. The average soil Se content in Qujing and Zhaotong cities in the study area was higher than in other areas. Correlation analysis showed that the correlation between soil selenium content and pH did not reach a significant degree. And soil Se content had a very significant positive correlation with soil organic matter (r = 0.110, p <0.001), indicating that organic matter affects soil Se content.