这项研究的重点是玉米(Zeamays)和/或豆类的单作和间作对Cu的植物减毒作用,Zn,Pb,和Cd在弱碱性土壤中。选择了单作玉米的9个生长阶段,研究了重金属提取的动态过程。单作玉米地上部分提取的重金属总含量在有效积温以上呈S形增加。最大的生物量,最高的提取含量,最低的重金属生物积累水平发生在生理成熟。在不同的种植模式中,包括玉米和/或大豆的单作和间作(甘氨酸max),豌豆(Pisumsativum),和苜蓿(紫花苜蓿),铜的提取效率,Zn,Pb,Cd变化很大。仅玉米和大豆的间作对四种金属的提取效率相对较高,而总生物量没有显着差异。此外,本研究中所有种植模式的干生物量中的重金属浓度均在中国国家法定的饲料使用阈值之内。因此,轻度污染的碱性土壤可以通过玉米和/或豆类的单作和间作安全地用于各种目的。特别是,这项研究表明,与单作相比,间作改善了受重金属污染的土壤生态系统。
The
study focused on the phytoattenuation effects of monocropping and
intercropping of maize (Zea mays) and/or legumes on Cu, Zn, Pb, and Cd in weakly alkaline soils. Nine growth stages of monocropping maize were chosen to
study the dynamic process of extraction of heavy metals. The total content of heavy metals extracted by the aerial part of monocropped maize increased in a sigmoidal pattern over the effective accumulative temperature. The biggest biomass, highest extraction content, and lowest heavy metals bioaccumulation level occurred at physiological maturity. Among the different planting patterns, including monocropping and intercropping of maize and/or soybean (Glycine max), pea (Pisum sativum), and alfalfa (Medicago sativa), the extraction efficiency of Cu, Zn, Pb, and Cd varied greatly. Only
intercropping of maize and soybean yielded relatively higher extraction efficiency for the four metals with no significant difference in the total biomass. Moreover, the heavy metals concentrations in dry biomass from all the planting patterns in the present
study were within China\'s national legal thresholds for fodder use. Therefore, slightly polluted alkaline soils can be safely used through monocropping and intercropping of maize and/or legumes for a range of purposes. In particular, this
study indicated that
intercropping improves soil ecosystems polluted by heavy metals compared with monocropping.