Abstract:
The objective of this paper was to clarify the vertical spatial variability of heavy metals in Guiding tea area by analyzing the heavy metal (As, Pb, Cr, Cd and Hg) contents in each soil horizon of different tea plantation and situ field. The results show that the heavy metal concentrations even decrease with increasing soil depth, and distribution characteristic of heavy metal in soil surface is obviously, and Pb and Cr contents have big variation. However, as has low spatial variation in topsoil, which indicate external pollution sources are the main causes. Organic matter is positive significantly correlated with all heavy metals in soil surface. Pb is highly significantly correlated with Cr in soil profile, which show a background level. The wild tea gardens which are far away from external pollution sources have lower heavy metal concentrations and lower vertical spatial variation than the other tea areas except Cd and Hg, which in artificial tea garden are opposite. Fang爷s tea plantation has the highest heavy metal contents, and Qi Lichong plantation has the greatest vertical spatial variation of As. Pb and Cr contents vary sharply in Yunwu central plantation and Jiuzhi plantation. The contents and vertical spatial variation order of heavy metals is artificial Niaowang tea plantation >artificial Fuding tea plantation>Niaowang wild tea plantation.