Abstract: Heavy metal pollution is one of the important factors affecting the ecological environment of tea gardens and the safety of tea products. This study collected literature on heavy metal (Cu, Pb, As, Hg, Cd, Cr, Zn, Ni) pollutions in tea garden soils in major tea producing areas in China, including Hubei, Hunan, Fujian, Yunnan, Guizhou and Sichuan. The weight of a single study was obtained using meta-analysis method to obtain the weighted average of heavy metal concentrations in tea garden soils in each province and across the country. The potential ecological risk index method and geological accumulation index method were used for ecological risk assessment, and source analysis using the APCS-MLR model was applied. The results show that compared with the background values, all 8 heavy metals were enriched to a certain extent, with Hg and Cd pollutions being more severe. The moderate and above risks of Hg were mainly distributed in inland provinces such as Guizhou, Shaanxi, Sichuan and Anhui. The moderate and above risks of Cd were mainly distributed in coastal provinces such as Guangdong, Fujian, Zhejiang, Jiangsu, Shandong, Hainan, etc. The two heavy metals show mild to moderate risks. Compared with other countries in the world, tea gardens or agricultural land in developing countries generally have higher levels of heavy metals, with Cd and Hg being the elements with more severe pollution levels. The source analysis results show that the first, second, third, and fourth principal components are natural sources, industrial activity pollution sources, traffic exhaust pollution sources, and agricultural activity pollution sources, respectively. Industrial and agricultural activities are the main pollution factors, with Hg mainly coming from industrial activities and Cd mainly coming from agricultural activities.

Key words: tea garden soil, heavy metal pollution, meta-analysis, risk assessment