鄂东某白茶园土壤特征分析和安全性评价

Analysis of Soil Characteristics and Safety Evaluation of a White Tea Garden in East Hubei

于2018年12月采集鄂东某白茶园表层土壤并开展土壤重金属和PAHs含量分析,以有机茶产地环境条件、茶叶产地环境技术条件和湖北土壤背景值为标准,探讨茶园土壤污染特征并作污染风险安全评价。结果表明,茶园土壤中不同的重金属含量差异显著,6个茶园土壤采样点中的重金属Zn、Pb、Cr、As的平均含量低于茶叶产地环境技术条件的要求,均不超标,Cu的平均含量为52.41 mg/kg,略高于有机茶产地环境条件50 mg/kg的要求,Ni、Mn、Co、V的平均含量为0.114~0.793 mg/kg,综合潜在生态风险评价结果显示该茶园属轻微生态污染;该茶园土壤中的PAHs总量、单个含量均未超过荷兰土壤中PAHs含量(10种)总量和加拿大制定的单个PAHs含量标准,这表明该茶园土壤未受到PAHs污染。通过风险评价可知,该茶场土壤整体质量总体良好,仅Cu的平均含量超标4.8%,需注意Cu潜在风险。

In December 2018,the surface soil of a white tea garden in the eastern Hubei was collected and analyzed for heavy metal and PAHs content.Based on the environmental conditions of the organic tea producing area,the environmental technical conditions of the tea producing area,and the Hubei soil background,the characteristics of the soil pollution in the tea garden were discussed and polluted risk safety assessment.The contents of different heavy metals in the tea garden soil were significantly different.The average contents of heavy metals Zn,Pb,Cr,and As in the six tea garden soil sampling points were lower than the environmental technical requirements of the place of origin of the tea,and they didn’t exceed the standard.The average Cu content was 52.41 mg/kg,which was slightly higher than the requirement of 50 mg/kg for the environmental conditions of the organic tea producing area.The average contents of Ni,Mn,Co and V were in the range of 0.114 and 0.793 mg/kg.Comprehensive potential ecological risk assessment results showed slight ecological pollution in tea plantations.The total amount and individual content of PAHs in the tea plantation soil did not exceed the total amount of PAHs(10 species) in the soil in the Netherlands and the single PAHs content formulated by Canada,which indicated that the tea plantation soil was not polluted by PAHs.According to the risk assessment,the soil quality of the tea plantation was better.The average content of Cu in the tea plantation soil exceeded the standard by 4.8%.