毛乌素沙地克隆植物生长对AM真菌多样性和菌根形成的影响

克隆植物的生态功能在沙地植被恢复过程中占据着重要位置。在毛乌素沙地由北向南选择两个典型样地,以根茎克隆植物沙鞭和羊柴为试验材料,连续2a系统地研究了克隆植物生长对AM真菌物种多样性和菌根形成的影响。结果表明:克隆植物生长对AM真菌物种多样性和丛枝菌根形成的影响因植物种类和样地不同而异。沙鞭通过克隆生长侵入灌丛空地后,AM真菌多样性指数在中国科学院植物研究所鄂尔多斯沙地草地生态研究站(简称OSES)和陕西榆林珍稀沙生植物保护基地(简称RSCF)样地均上升;孢子密度、菌丝、丛枝和总定殖率均显著提高;泡囊定殖率也有所增加,在OSES样地达显著水平,在RSCF样地未达显著水平。羊柴通过克隆生长侵入灌丛空地后,AM(Arbuscular mycorrhizal)真菌多样性指数在OSES样地上升,而在RSCF样地下降;孢子密度和丛枝定殖率在OSES和RSCF样地均显著增加,而泡囊定殖率均显著降低;菌丝和总定殖率也降低,在OSES样地未达显著水平,在RSCF样地达显著水平。

Effects of the growth of clonal plants on the diversity of AM fungi and mycorrhizal formation in Mu Us sandland

The research investigated the effects of the growth of clonal plants on the diversity of AM fungi and mycorrhizal formation over two years at two representative sites, OSES and RSCF, from north to south, in Mu Us sandland. The clonal plants were Psammochloa villosa and Hedysarum leave. The results showed that the ability of clonal plants to increase the diversity of AM fungi and mycorrhizal formation differ between plant species and sampling sites. After P. villosa invasion, the Shannon-Weiner index of AM fungi rose in both sampling sites. Additionally, the spore density level, the colonization rate of hyphae and arbuscules, the total colonization rate and colonization rate of vesicles all significantly increased. After H. leave invasion, the Shannon-Weiner index of AM fungi rose in OSES but descended in RSCF. At both sites, the spore density and colonization rate of arbuscules significantly increased and, at each, the colonization rate of vesicles rose to a maximum then declined. At OSES the hyphae and total colonization rate rose to a maximum and remained but at RSCF these values declined significantly after peaking.