施磷肥对土壤—水稻体系中Hg迁移累积规律的影响

Influence of Phosphate Fertilizer on Hg Accumulation in the Soil-Rice System

对水稻田施用不同剂量磷肥,定期测定土壤、水稻根、茎、叶和子粒中的Hg的动态变化,研究Hg在土壤和水稻各器官中的分配累积、动态变化规律,以及Hg在土壤和水稻植株各器官的累积量与磷肥施用量的相关性等。结果表明:在水稻成熟期,在4个不同磷肥水平下,土壤和植株中Hg的含量与磷肥施用量存在明显的剂量效应,Hg在土壤及水稻植株不同器官的含量分布由大到小的次序为土壤>根>茎>叶>穗;叶、穗中重金属Hg含量总体趋势为先升高后下降,根中重金属Hg含量除10月初出现几个高值外,总体趋势为平稳,茎中重金属Hg含量总体趋势为下降;Hg在土壤和水稻各器官累积量与磷肥施用量达到极显著相关;Hg在水稻植株体内富集系数为根>茎>叶>穗。

In this study rice was treated with different doses of phosphate, Hg in soil and various organs of rice were analyzed by dynamic measurement. The rules of distribution and accumulation, dynamic change and the correlation of cumulative between heavy meals and soil and rice organs under different levels of phosphate were studied. The results showed： in mature stage, the content of Hg in soil and plants related to phosphate exists a clear dose-response under four different levels of phosphate. The distribution of Hg in soil and rice plants with different organs was as follows： soil 〉 root 〉 stem 〉 leave 〉 ear. The trend of Hg content in root was smooth in addition to a few high-value occurred in early October. The trend of Hg content in stem was declined, and in leaf and ear was first increased and then decreased. The accumulated contention of Hg in soil and various organs of rice reached a very significant correlation with phosphate fertilization. The enrichment rule ofhtg in soil-riee system under different levels of phosphate：ro6t 〉 stem〉 leave 〉 ear.