岳西县来榜镇茶园根系土与茶叶中硒含量状况及影响因素

采集岳西县来榜镇茶园的25件茶叶样品及根系土,分析茶园根系土和茶叶中硒含量及其影响因素。结果表明:根系土壤硒含量为0.11~0.38mg/kg,平均值为0.21mg/kg,参照土地质量地球化学评价规范,根系土均未达到富硒标准。土壤浸提硒含量为0.004~0.013mg/kg,平均值为0.008mg/kg。茶叶硒含量为0.17~0.66mg/kg,平均值为0.37mg/kg,采集的25件茶叶样品有22件达到了富硒茶标准。土壤不富硒,但茶叶富硒率高,认为岳西翠兰茶树属于对硒元素富集能力较强的植物,采样茶树均生长周期较长,可能是茶树对硒元素产生了一定的累积效应。土壤硒、浸提性硒主要受有机质、全氮、速效钾的影响,与部分重金属相伴生。茶叶硒与土壤养分、理化性质、有效态相关性均不明显,与重金属中生物毒性响应系数较大的4种元素呈负相关的趋势。

SELENIUM CONTENTS IN TEA PLANT ROOT SOIL AND TEA LEAVES AND FACTORS INFLUENCING THEM FOR THE LAIBANG TOWN TEA GARDEN,YUEXI COUNTY

Twenty-five tea samples and tea plant root soil from tea garden in Laibang Town,Yuexi County were collected to analyze the selenium contents in the tea plant root soil and tea leaves and the factors influencing them.The results showed that the selenium content in the root depth soil was 0.11-0.38 mg/kg,with an average of 0.21 mg/kg.The content of selenium extracted by soil leaching was 0.004-0.013 mg/kg,with an average of 0.008 mg/kg.The selenium content in tea leaves was 0.17-0.66 mg/kg,averaging 0.37 mg/kg.Of the 25 tea samples collected,22 reached the standard of selenium-rich tea.The soil is not rich in selenium,but the tea has high selenium enrichment rate.It is suggested that the tea plant Yuexi Cuilan belongs to the plant with strong ability for selenium enrichment,and the sampled tea plants all have a long growth cycle,so they probably exhibit a certain effect of accumulation of selenium.Soil selenium and leaching selenium are mainly affected by organic matter,total nitrogen,rapidly available potassium,and associated with some heavy metals.The correlation between tea selenium and soil nutrients,physical and chemical properties and available states was not obvious,and the correlation between selenium and the four heavy metals with high reaction coefficient of biotoxicity was negative.