贵州省西秀区耕地土壤硒元素地球化学特征及成因分析

Analysis on Geochemical Characteristics and Genesis of Selenium Element in Cultivated Soil of Xixiu District,Guizhou Province

为促进地方特色农业发展,以西秀区耕地质量地球化学调查成果数据为基础,用生态地球化学研究方法,分析西秀区耕地土壤硒元素地球化学特征及分布规律,探讨土壤硒元素来源、富集成因及特色农业效应。结果表明,研究区耕地土壤中硒元素平均含量为0.56 mg/kg,高于全国土壤(A层)平均值,总体较丰富,土壤硒元素含量在0.4~3.0 mg/kg的富硒耕地占全区耕地总面积的89.40%。研究区土壤硒含量明显受土壤类型、土地利用方式和有机质含量的影响,在一定范围内与pH值呈负相关关系,而且与Mo、Cd、As、Zn等重金属均具有正相关关系,相关系数均低于0.50,也进一步说明硒对成土母质具有一定的继承性,同时也受外源的补给。富硒耕地分布区产出有富硒水稻、富硒茶叶、富硒油菜,富硒率分别为62.5%、62.5%和100%,显示了富硒产业发展潜力。

In order to promote the development of agriculture with local characteristics,based on the results of the survey of cultivated land quality in Xixiu District,the characteristics and distribution of soil selenium in Xixiu District were analyzed by using the method of ecological geochemistry,which was used to study the geochemistry of soil selenium,the source,accumulation and agricultural effects of selenium in soil were studied.The results showed that the average content of Se in cultivated soil was 0.56 mg/kg,and higher than the average value of A layer in China,the Selenium element is generally rich.The content of Se in soil is 0.4~3.0 mg/kg,which accounts for 89.40%of the total area of cultivated land.The soil Selenium content in the study area was obviously affected by soil type,land use pattern and organic matter content,and was negatively correlated with pH value in a certain range,and positively correlated with heavy metals,such as Mo,Cd,As,Zn,and so on.It is further explained that selenium has certain inheritance to the parent material of soil formation,and is also supplied by external sources.The correlation coefficients were all lower than 0.50.The Se-enriched Rice,tea and rape were produced in the Se-enriched cultivated land,and the Se-enriched rates were 62.5%,62.5%and 100%,respectively,which showed the potential of Se-enriched industry.