长沙市茶园土壤和茶叶重金属的检测与评价

目的]了解长沙市茶场土壤及茶叶重金属的污染情况,为茶场无公害建设提供科学依据。方法]分别测定长沙市的金井、湘丰、淳口、银峰和沩山茶场中某个茶园的土壤及茶树新叶、老叶的Pb、Cu、Cr、Cd、Hg和As 6种重金属元素含量,并结合茶场土壤和茶叶的卫生质量标准,使用单项污染指数和Nemerow综合污染指数对茶园土壤和茶叶进行评价。结果]5个茶园土壤和茶叶的Pb、Cu、Cr、Cd、Hg和As重金属元素含量均低于规定含量限定值,单项污染指数和Nemerow综合污染指数均小于1.0。结论]5个茶园土壤环境总体良好,符合无公害茶场建设的条件;茶叶重金属含量在规定含量限定范围内,符合1级茶叶产品标准。

Monitoring and Evaluating of Heavy Metals in Soil and Teas of Tea Garden in Changsha City

Objective] The research aimed to understand the heavy metals elements contamination in Changsha City,and to provide the basis for building non-polluted agriculture.Method] We monitored the contents of heavy metals such as Pb,Cu,Cr,Cd,Hg and As in soil and teas of a Jinjing,Xiangfeng,Chunkou,Yinfeng and Weishan tea garden in Changsha City.Combined with health quality standard of tea gardens soil and tea,pollution of heavy metals was evaluated by single factor pollution index and Nemerow pollution index.Result]The contents of Pb,Cu,Cr, Cd,Hg and As were fit the standard in garden soil,and the single factor pollution indexes and Nemerow pollution indexes were both less than 1.0. Conclusion] Five tea gardens soil environmental quality was cleanness,and the soils were suitable for non-polluted agricultural production.The contents of heavy metals in tea leaves is within the limited range of the prescribed content and fits the first-level tea product standard.