皖南茶区土壤硒含量及其与茶叶中硒的关系

Soil and tea selenium in tea gardens in South Anhui.

采集皖南泾县茶区7个主要茶园和安徽茶树良种场土壤和茶叶样品,分析土壤-茶叶间硒分配与分布的特点以及茶叶中硒含量与土壤和茶树品种的关系。结果表明,皖南泾县茶区土壤硒平均含量为( 0. 413±0. 146 )mg·kg-1,高于我国土壤表层硒平均含量背景值,在我国自然茶园中属正常偏高水平。硒在土壤剖面的分布受生物富集性、土壤pH值、土壤有机质含量等因素的影响。春茶含硒量高于秋茶,春茶含硒量为0. 096 ~0. 216mg·kg-1,多数属中等含硒水平。茶叶含硒量是土壤含硒量、茶叶采摘季节、茶树品种等因素共同影响的结果。因此通过选育硒富集力强的良种茶树、合理配施硒肥、调节土壤pH值及养分状况以及适时采摘茶叶等措施,可以实现富硒绿茶生产。

Samples of soils and tea leaves in both spring and autumn were collected from seven typical tea gardens in Jing County and the Anhui Provincial Tea Cultivar Breeding Garden,and contents of total selenium in the samples were determined in an attempt to investigate selenium partitioning between soil and tea,distribution of Se in tea organs and their relationship with the soils and tea cultivars.Results show that the average soil Se were (0.413±0.146) mg·kg^(-1),higher than the average background value of China.Distribution of soil Se in the soil profile varies with soil depth,soil pH,and organic matter content.And the spring tea was medium in Se level(0.096~0.216 mg·kg^(-1)),but higher than the autumn tea.Thus,Se content in tea is resulted from a common function of soil Se,tea harvesting season and tea cultivar.Production of green tea with high Se could,therefore, be achieved through breeding Se-accumulating cultivars,rationalizing Se fertilizer application,regulating soil pH,and timing of harvesting.