中文摘要：

通过对159个市售磷肥样品中重金属Cd总量和有效态含量的检测,分析了其环境风险和生物有效性。结果表明,磷肥中重金属Cd总量和有效态含量的平均值分别为0.77和0.14 mg/kg肥料;以P_2O_5为基础计算,Cd总量和有效态含量的平均值分别为4.48和0.89 mg/kg P_2O_5。根据肥料中砷、镉、铅、铬、汞生态指标标准限值（GB/T 23349-2009）,只有1个磷酸二铵样品中Cd含量超过限值10mg/kg肥料。小麦盆栽试验结果表明,磷肥中Cd的生物有效性要显著低于无机盐中的Cd,无机Cd盐处理的小麦植物体内Cd的含量为磷肥处理的1.59~7.91倍。此外,以每年土壤中磷肥（以P2O5计）施用量为80 kg/hm2计算,以50%分位值分析,每年随磷肥施用带入耕层土壤中Cd的累积速率为0.052μg/（kg·a）,50年后会使土壤中Cd的浓度增加2.57μg/kg,100年增加5.15μg/kg。

英文摘要：

In order to investigate the environmental risk of cadmium（Cd） and its bioavailability in phosphorus fertilizers, 159 samples of commercial phosphorus fertilizers were collected to determine their total and available Cd contents. Results showed that the mean contents of total and available Cd in phosphorus fertilizers were 0.77 and 0.14 mg/kg fertilizer, respectively.Based on the calculation of P_2O_5, the mean contents of total and available Cd were 4.48 and 0.89 mg/kg P_2O_5, respectively.According to ecological index of arsenic, cadmium, lead, chromium and mercury for fertilizers in GB/T 23349-2009, only one diammonium phosphate sample exceeded the limit for Cd. Pot experiment results showed that the Cd bioavailability to wheat in phosphorous fertilizers was significantly lower than that of Cd salt, and Cd concentration of wheat seedlings in the salt treatments was 1.59 ~7.91 times higher than that in the phosphorous fertilizer treatments. Moreover, in case of median scenario, the annual Cd input rate in the plough layer was 0.052 μg/（kg·a） due to the application of phosphorous fertilizers（80 kg/hm~2P_2O_5 per year）, the Cd concentration will increase by 2.57 μg/kg after 50 years of application, and 5.15 μg/kg after100 years.