High levels of mercury (Hg), especially methylmercury (MeHg), in rice is of concern due to its potential of entering food chain and the high toxicity to human. The level and form of Hg in rice could be influenced by fertilizers and other soil amendments. Studies were conducted to evaluate the effect of 24 years application of chemical fertilizers and organic amendments on total Hg (THg) and MeHg and their translocation in soil, plants, and rice grain. All treatments led to significantly higher concentrations of MeHg in grain than those from the untreated control. Of nine treatments tested, chemical fertilizers combining with returning rice straw (NPK1+S) led to highest MeHg concentration in grain and soil; while the nitrogen and potassium (NK) treatment led to significantly higher THg in grain. Concentrations of soil MeHg were significantly correlated with THg in soil (r = 0.59^***) and MeHg in grain (r = 0.48^***). Calcium superphosphate negatively affected plant bioavailability of soil Hg. MeHg concentration in rice was heavily influenced by soil Hg levels. Phosphorus fertilizer was a main source contributing to soil THg, while returning rice straw to the field contributed significantly to MeHg in soil and rice grain. As a result, caution should be exercised in soil treatment or when utilizing Hg-contaminated soils to produce rice for human consumption. Strategic management of rice straw and phosphorus fertilizer could be effective strategies of lowering soil Hg, which would ultimately lower MeHg in rice and the risk of Hg entering food chain.

大米中的汞（Hg），尤其是甲基汞（MeHg）含量高，令人担忧，因为它有可能进入食物链，并且对人体有很高的毒性。水稻中汞的含量和形式可能受肥料和其他土壤改良剂的影响。进行了研究以评估24年施用化肥和有机改良剂对总Hg（THg）和MeHg以及它们在土壤，植物和稻米中的转运的影响。与未处理的对照相比，所有处理均导致谷物中的MeHg浓度显着升高。在经过测试的9种处理方法中，化学肥料与返还的稻草（NPK1 + S）相结合导致谷物和土壤中的MeHg浓度最高。而氮和钾（NK）处理导致谷物中的THg显着升高。r = 0.59 ^***）和谷物中的MeHg（r = 0.48 ^***）。过磷酸钙对土壤汞的植物生物利用度有负面影响。水稻中的甲基汞浓度受土壤汞含量的严重影响。磷肥是造成土壤THg的主要来源，而稻草还田则对土壤和稻谷中的MeHg贡献很大。因此，在土壤处理或利用受汞污染的土壤生产供人食用的大米时应格外小心。稻草和磷肥的战略管理可能是降低土壤汞的有效策略，这最终将降低水稻中的MeHg和汞进入食物链的风险。