汨罗市桃林寺镇土壤硒元素地球化学特征分析

Geochemical Characteristics of Selenium Elements in Soil of Taolinsi Town,Miluo City

为查清汨罗市桃林寺镇土壤硒元素地球化学特征,通过采集桃林寺镇土壤样品495件,农产品样品87件,土壤垂向剖面样品5个进行研究。结果表明:区内土壤表层硒含量为0.21~0.81 mg/kg,平均值为0.42mg/kg,高于全国背景值和洞庭-江汉平原土壤背景值,富硒土壤面积比例达到73.29%;土地利用方式对土壤硒的富集也产生一定的影响,影响大小表现为:林地>水田>旱地;土壤硒含量与土壤pH呈负相关;4个水田中土壤垂向剖面总体呈现硒元素的表层聚集型,而位于旱地的1个剖面呈现为心土层聚集型。红薯及花生富硒率分别为78.57%和100%,同时这两种农产品大多数样品内重金属元素含量均符合国家食品安全标准。这些研究成果可为当地富硒土壤资源开发利用等提供参考。

In order to verify the geochemical characteristics of selenium in soil of Taolinsi Town,Miluo City,495 soil samples,87 agricultural products samples and 5 vertical soil profile samples were sampled.The results show that the surface selenium content was 0.21~0.81 mg/kg,with an average of 0.42mg/kg,which was higher than the national background value and the Dongting-Jianghan Plain soil background value,and the proportion of selenium-enriched soil area reached 73.29%.Land use type also had a certain effect on soil selenium enrichment,and the effect was as follows:forest land>paddy field>dry land.Soil selenium content was negatively correlated with soil pH.The vertical profile of the soil in the four paddy fields showed the accumulation type of selenium in the surface layer,while the profile in the dry land showed the accumulation type of selenium in the core layer.The selenium enrichment rates of sweet potato and peanut were 78.57%and 100%,respectively.Meanwhile,the content of heavy metal elements in most samples of these two agricultural products met the national food safety standards.These results can provide reference for the exploitation and utilization of local selenium-riched soil resources.