土壤元素的测定及其对茶叶浸出液元素的影响

Determination of elements in soil and effects on elements in leaching liquid of tea leaves

目的探究土壤元素种类及含量对不同成熟度茶叶元素含量的影响。方法取来自韶关、廉江、梅州和潮州四地土壤和不同成熟度的茶叶,样品经磨碎、脱硫、加热、溶解、离心后取上清液,采用原子吸收光谱法检测所含32种元素单质锂(Li)、钡(Be)、钪(Sc)、钒(V)、铬(Cr)、钴(Co)、镍(Ni)、铜(Cu)、锌(Zn)、镓(Ga)、砷(As)、铷(Rb)、锶(Sr)、钇(Y)、镐(Zr)、铌(Nb)、铯(Cs)、钡(Ba)、铪(Hf)、钽(Ta)、钨(W)、铊(Tl)、铅(Pb)、铋(Bi)、锗(Ge)、钼(Mo)、银(Ag)、镉(Cd)、铟(In)、锡(Sn)、锑(Sb)、硒(Se)和6种元素化合物氧化镁(Mg O)、五氧化二磷(P5O2)、氧化钙(Ca O)、二氧化钛(Ti O2)、氧化锰(Mn O)、三氧化铁(Fe2O3-T)的含量。结果不同成熟度的茶叶浸出液与不同土壤元素含量的相关性不显著,Zn、Ga、Sr含量与成熟度的相关性极显著,Cu、Ba、Pb含量与成熟度的相关性显著;茶树对处于元素周期表第四、第五周期的ⅠA、ⅢA、ⅣA、ⅠB、ⅣB、ⅤB、Ⅷ的元素选择性吸收较强;对Sr、P2O5、Ca O、Mn O的富集作用较强。结论茶树叶片各元素含量受土壤中该元素含量的影响较小,成熟度是影响茶叶浸出液元素含量的重要因素。

Objective To study the content of elements in tea leaves under the influence of kinds and content in soil. Methods Content of 32 single elements including Li, Be, Sc, V, Cr, Co, Ni, Cu, Zn, Ga, As, Rb, Sr, Y, Zr, Nb, Cs, Ba, Hf, Ta, W, Tl, Pb, Bi, Ge, Mo, Ag, Cd, In, Sn, Sb, Se and 6 element compounds including Mg O, P5O2, Ca O, Ti O2, Mn O, Fe2O3-T in soil and leaching liquid of tea leaves of different grade of maturity from Shaoguan, Lianjiang, Meizhou and Chaozhou were detected by atomic absorption spectroscopy, after grinding, desulfurization, heating, dissolution and centrifugation. Results Correlation of elements between soil and leaching liquid of tea leaves of different grade of maturity had no significant difference, but there was a highly significant correlation between content of Zn, Ga, Sr and grade of maturity, and a significant correlation between content of Cu, Ba, Pb and grade of maturity. Elements in ⅠA, ⅠA, ⅠA, ⅠB, ⅠB, ⅠB, Ⅰ of fourth and fifth cycle in element periodic table were extremely selectively absorbed by tea plants. furthermore, Sr, P2O5, Ca O and Mn O were more easily absorbed by tea plants. Conclusion Content of elements in tea leaves is weakly influenced by that in soil, while greatly influenced by maturity.