茶园土壤砷的形态研究

Forms of arsenic in tea garden soils. Journal of Zhejiang Agricultural University

参照改进的张守敬－Ｊａｃｋｓｏｎ无机磷分级体系，可以把土壤无机砷分成水溶态砷（Ｈ２Ｏ－Ａｓ）、铝型砷（Ａｌ－Ａｓ）、铁型砷（Ｆｅ－Ａｓ）、钙型砷（Ｃａ－Ａｓ）和闭蓄态砷（Ｏ－Ａｓ）．本文分析了我国东南部一些茶园土壤砷的形态后认为：Ｈ２Ｏ－Ａｓ含量在不同的土壤中变幅不大，它与土壤锰含量有显著负相关性，与ｐＨ值有显著正相关性；Ａｌ－Ａｓ含量在土壤中所占比例不大，它与土壤全铝含量关系密切，而与游离氧化铝关系不大；Ｆｅ－Ａｓ在土壤中占有较大比重，含钙、镁、锰、铝高的土壤，Ｆｅ－Ａｓ含量低一些；Ｃａ－Ａｓ在土壤中所占比例也较少，它与土壤含钙量有密切关系；土壤中的砷绝大部分以Ｏ－Ａｓ形态存在．

Many tea garden soils collected from Southeastern China were studied and the results can be summed as follows: ①Contents of H 2O As in soils have no obvious difference, but have markedly negative correlation with the contents of manganese, and have obvious correlation with the pH value; ②Contents of Al As in soils are lower than other forms of arsenic except for the contents of H 2O As ,and have no relation with the contents of dissociate aluminum, but have obvious correlation with the contents of aluminum; ③Contents of Fe As in soils occupy high proportion of total arsenic ,but when the contents of calcium, magnesium, manganese, and aluminum are high, the contents of Fe As are lower relatively; ④Contents of Ca As in soils are related with the contents of calcium; ⑤Majority of arsenic in soils are O As, which may occupy 85% of the total arsenic.