贵州荔波富硒耕地土壤硒分布特征及影响因素

Distribution characteristics and influencing factors of Se in selenium-rich cultivated land in Libo,Guizhou

依据荔波县耕地质量地球化学调查成果,对富硒耕地土壤硒分布特征和影响因素进行了分析。结果显示,富硒耕地表层土壤硒含量在0.30×10^(-6)~9.49×10^(-6),平均值为0.58×10^(-6);土壤中硒含量受成土母岩、土地利用方式、土壤类型和土壤有机质含量等的影响,炭质泥页岩和煤系地层分布区土壤硒含量普遍高于其他成土母岩分布区,黄壤和红壤硒含量明显大于水稻土,林地、草地和茶园中硒含量高于其他土地利用类型,土壤有机质含量与硒含量呈现正相关性。土壤硒主要来自成土母岩的风化,成土母岩对土壤中硒元素的含量具有控制作用。同时,次生富集作用是碳酸盐岩分布区土壤硒相对富集的重要原因。

Based on the investigation of cultivated land quality in Libo,the distribution characteristics and influencing factors in soil of Se-rich cultivated land were analyzed.The results showed that the content of Se in the topsoil is from 0.30×10^(-6) to 9.49×10^(-6).The average content of Se is 0.58×10^(-6).The content of Se in soil is decided by the parent soil,land use,soil type and soil organic matter content.The Se content of soil in the area of carbonaceous shale and coal measures strata is higher than those of other parent rocks.The Se contents in yellow earth and red earth are obviously higher than paddy soil.The content of Se in forest land,grassland and tea garden soil is higher than those in other land use type.There is a positive correlation between soil organic content and selenium content.It is found that Se in soil mainly comes from weathering of parent rock which wsually controls the content of Se in soil.While secondary enrichment of Se comes carbonate rock distribution area.