接种丛枝菌根对鬼针草吸收煤矿区土壤重金属的影响

摘要

In order to better expand land reclamation and ecological reconstruction of wasteland of coal mine tailing in Mingshan,effect of inoculation of Bidens bipinnata (a kind of indigenous pioneer plant) with arbuscular mycorrhizal fungi on the plants absorbing soil heavy metal was studied in an experiment that was designed to have three ratios of mixture of yellow earth and coal gangue and four species of arbuscular mycorrhizal fungi,i.e.Glomus intraradices BGC BJ09 (A1),G.mosseae BGC NM01A (A2),G.mosseae BGC HEB07B (A3) and G.versiforme BGC GD01C (A4) for comparison.Results show that A4 is the most suitable inoculant for Bidens bipinnata,in terms of biomass of the host,mycorrhizal infection rate and intensity,spore density (per 50 g dry soil),and root activity.Compared with CK,A1 promoted Cd uptake of the plant; the 4 treatments are all insignificant in their effects on absorption or repulsion of Cu and Mn; A3 significantly promoted removal of Cu and Mn,while A4 did that of Mn.Biomass of the inoculated plants in treatments of 2 cmthick overlaying yellow earth layer on 9 cm-thick coal gangue is higher than that of uninoculated plants in treatments of 7cm-thick overlaying yellow earth layer on 4 cm-thick coal gangue,indicating that the inoculation has the potential of offsetting the effect of thin overlaying reducing biomass of the plants.It could,therefore,be concluded that the practice of arbuscular mycorrhizae inoculation may reduce the need for thick overlaying soil layer,and hence significantly save the cost of land reclamation.%以广东梅州明山煤矿尾矿区土著先锋植物鬼针草(Bidens bipinnata)为研究对象,开展3种黄土与煤矸石基质配比条件下根内球囊霉(Glomus intraradices BGC B J09)(A1)、摩西球囊霉(G.mosseae BGC NM01A)(A2)、摩西球囊霉(G.mosseae BGC HEB07B)(A3)和地表球囊霉(G.versiforme BGC GD01C)(A4)这4种丛枝菌根真菌接种对土壤重金属的吸收对比研究.结果表明,从宿主生物量、菌根侵染率及侵染强度、孢子密度、根系活力来看,A4是最适合鬼针草的菌种.与对照(4种菌剂混合后灭菌)相比,A1可显著促进地上部Cd吸收;4种菌根对Cu和Mn的吸收-排斥效应均不显著,但接种A3对地下部Cu和Mn以及接种A4对地下部Mn的移除量显著增加;接种4种菌根处理的Ni移除量均显著增加.接种菌根且覆土少(2 cm厚黄土覆于9 cm厚煤矸石上)的处理植株生物量均高于不接种且覆土厚(7 cm厚黄土覆于4 cm厚煤矸石上)的处理,说明接种菌根具有抵消由于覆土少而导致的植株生物量降低的潜力,极大地节约复垦费用.