施肥对两种苋菜吸收积累镉的影响

通过盆栽试验,研究了生长在5 mg/kg镉(Cd)污染土壤中的两种苋菜(红苋(Amaranthus Paniculatus L.)和绿苋(Amaranthus Paniculatus L.))在3种施肥处理下(N、NP和NPK)的生长状况和对Cd的吸收积累情况。结果表明,两种苋菜能够在污染土壤中正常生长,各器官中叶Cd含量最高,范围为124.1—225.9 mg/kg;根中次之,范围为57.1—100.6 mg/kg;茎中最低,范围为56.2—87.6 mg/kg;富集系数高达22.4—40.2。施加N,NP,NPK肥对两种苋菜器官中的Cd含量和生物量有显著影响。其中,施加NPK肥使红苋和绿苋的生物量分别达到不施肥(对照)处理的3.5和3.2倍,单株提取Cd的总量是对照3.2和5.0倍。综上表明,两种苋菜(红苋和绿苋)具有生物量大、易栽培、施加NPK肥能够大幅增加生物量的同时不减少器官对Cd的吸收等优点,作为Cd污染土壤的修复植物有巨大应用前景。

Effect of fertilizers on cd uptake of two edible amaranthus herbs

We assessed the phytoextraction potential for Cd of two edible amaranthus herbs (red amaranth: Amaranth Paniculatus L. and green amaranth: Amaranth Paniculatus L.)and the effect of application of N, NP and NPK fertilizers on Cd uptake of the two cultivars from soil contaminated with 5 mg/kg Cd. Two edible amaranthus herbs had high levels of Cd concentration in their tissues, ranging from 124.1 to 225.9 mg/kg in leaves, from 56.2 to 87.6 mg/kg in stems, and from 57.1 to 100.6 mg/kg in roots, resulting in average Bioaccumulation Factors(BCF) ranging from 22.4 to 40.2. Application of N, NP or NPK fertilizers had significantly influenced Cd content in leaves, stems and roots. Fertilizers of NPK fertilizer greatly increased dry biomass, by a factor of 3.5 for red amaranth or 3.2 for green amaranth, resulting in a large increment of Cd uptake per plant. Two edible amaranthus herbs have great potential in phytoremediation of Cd contaminated soil. They have the merits of high Cd content in tissues, high biomass, easy cultivation, and little effect on Cd uptake by fertilization.