Zhang M K, He Z L, Calvert D V, Stoffella P J, Yang X E, Lamb E M
Department of Resource Science, College of Natural Resource and Environmental Sciences, Zhejiang University, Huajiachi Campus, Hangzhou, PR China.
J Environ Sci Health A Tox Hazard Subst Environ Eng. 2003 Sep;38(9):1981-95. doi: 10.1081/ese-120022894.
Increased inputs of phosphorus (P) and heavy metals to agricultural soils have caused considerable concern. Information on accumulation and chemical forms of the elements in soils is needed as a guide for the judicious application of agricultural chemicals and organic manures. The focus of this study was to assess accumulation of P and heavy metals among various fractions of a sandy soil with a 25 year history of vegetable crop production and primarily inorganic fertilization. The results demonstrated that long-term vegetable production practices changed concentrations and partitioning of P and heavy metals in the soil. Phosphorus, Cu, Zn, and Mn were significantly accumulated and moved downward along the soil profile. Most of the total Cr in the vegetable soil accumulated in the upper 0-15 cm. However, there was no significant accumulation and transport of Cd, Co, Mo, Ni, and Pb in the vegetable soil. Major P fractions in the vegetable soil were NaHCO3-P, followed by HCl-P and residual P. Copper, Zn, and Mn accumulated predominantly in the CaCO3 fraction or oxide fraction, whereas Cr accumulated mainly in the organically bound fraction, indicating that P, Cu, Zn, and Mn in the vegetable soil have greater mobility potential. Compared with adjacent forest soil, the vegetable soil had a lower percentage of P, Cu, Zn, and Mn in the residual fractions, and a higher percentage of P, Cu, Zn, and Mn in the CaCO3 fractions or organically bound fraction.
农业土壤中磷（P）和重金属输入量的增加已引起广泛关注。需要了解土壤中这些元素的积累情况和化学形态，以为合理施用农药和有机肥料提供指导。本研究的重点是评估在有25年蔬菜作物生产历史且主要施用无机肥料的砂质土壤的不同组分中磷和重金属的积累情况。结果表明，长期的蔬菜生产实践改变了土壤中磷和重金属的浓度及分布。磷、铜、锌和锰显著积累并沿土壤剖面下移。蔬菜土壤中大部分总铬积累在0-15厘米的上层土壤中。然而，蔬菜土壤中镉、钴、钼、镍和铅没有显著积累和迁移。蔬菜土壤中的主要磷组分是碳酸氢钠磷，其次是盐酸磷和残留磷。铜、锌和锰主要积累在碳酸钙组分或氧化物组分中，而铬主要积累在有机结合组分中，这表明蔬菜土壤中的磷、铜、锌和锰具有更大的迁移潜力。与相邻的森林土壤相比，蔬菜土壤中残留组分中磷、铜、锌和锰的比例较低，而碳酸钙组分或有机结合组分中磷、铜、锌和锰的比例较高。
