关键词: 水稻, 水稻, 剑叶角度, 氮营养效率

Abstract: The basic ecotoxicological data of soil pollutants are essential to the assessment of ecological risks and the development of ecological soil screening levels. Fluvo- aquic soil was used as the test substrate, artificially contaminated soils were made by adding nickel with the concentrations of 0, 10, 18, 32, 56, 100, 180, 320, 560, 1000 and 1780 mg/kg. Nickel toxicity to root elongation of monocotyledons (barley, wheat and oat) and dicotyledons (cucumber, lettuce and rape) were evaluated by the method of ISO 11269-1—2012, and the residue amount of nickel in the soil was determined. Meanwhile, nickel toxicity to reproduction (cocoon production) and the growth (body weight change) of earthworm Eisenia fetida were studied using the series of nickel contaminated soils (except the soil of 1780 mg/kg Ni). The hytotoxicity test results showed that low levels of added nickel could promote the elongation of barley and wheat roots, indicated that there was a hormesis. However, high levels of nickel could significantly inhibit the root elongation of the six plants. The EC50 values of root elongation of barley, wheat, oats, cucumber, lettuce, and rape were 918.3, 696.6, 837.5, 409.3, 232.3 and 608.1 mg/kg, respectively. Nickel toxicity to the root elongation of dicotyledons was generally larger than that of onocotyledons. The earthworm toxicity test results showed that nickel at the range of 0- 1000 mg/kg in fluvo-aquic soils had no significant effect on the body weight of earthworms. However, nickel at the concentration of 180 mg/kg or more showed significant toxic effect on earthworm cocoon production, which lead to a decrease in the roduction of cocoon. The EC50 value of the cocoon production was 329.61 mg/kg. The data obtained in this study could promote the development of ecological soil criteria and the assessment of ecological risk of nickel.