Data from: The missing link in grassland restoration: arbuscular mycorrhizal fungi inoculation increases plant diversity and accelerates succession

Because soil microbial communities are often altered by anthropogenic disturbance, successful plant community restoration may require the restoration of beneficial soil microbes, such as arbuscular mycorrhizal (AM) fungi. Recent evidence suggests that later successional grassland species are more strongly affected by AM fungi relative to early successional plants and that late successional plants consistently benefit from some AM fungi but not other AM fungal species. Many of these late successional species are also often missing in restorations despite being heavily seeded. To assess the effects of AM fungal composition within grassland restorations, we inoculated plots with six different AM fungal community treatments including one of four different AM fungal species isolated from a prairie, a mixture of all four fungal species, and a non-inoculated control. AM fungi were introduced by planting 16 different inoculated nurse plants into replicated plots. We also seeded the restoration with a diverse, 54 species prairie seed mixture. We found that AM fungal inoculation drove plant community composition; plots inoculated with certain AM fungal treatments were dominated by desirable prairie plants, whereas plots inoculated with other AM fungal species and the non-inoculated control were dominated by non-desirable plants including weeds and exotic species. Specifically, we found that many early successional species established well regardless of AM fungal inoculation, whereas the establishment and growth of many late successional species was strongly dependent on the presence of specific AM fungal species. Many conservative late successional species did not occur without inoculation. Overall, total plant community richness, diversity, and Floristic Quality Index were all significantly improved with AM fungal inoculation, whereas we observed that non-desirable plant abundance was significantly greater in the non-inoculated plots. Synthesis and applications. Our results suggest that the lack of late successional establishment reported in many previous restorations may be due to ineffective arbuscular mycorrhizal fungal communities at these sites. We conclude that the reintroduction of arbuscular mycorrhizal fungi from reference prairie environments could improve restoration outcomes by promoting plant diversity and richness, especially for desirable later successional plant species, while simultaneously inhibiting less desirable weedy plants.由于土壤微生物群落常受人为干扰影响而发生改变，因此要成功实现植物群落修复，可能需要同步恢复有益土壤微生物，例如丛枝菌根（arbuscular mycorrhizal, AM）真菌。已有研究表明，相较于演替早期植物，演替后期的草本植物受AM真菌的影响更为显著；且演替后期植物仅能从部分AM真菌类群中获益，而非所有AM真菌物种。尽管在修复过程中大量播种，但许多这类演替后期物种仍难以在修复样地中存活定植。 为探究AM真菌群落组成对草地修复的影响，我们设置了6种不同的AM真菌群落处理组对样地进行接种：其中4组分别接种从原生草原分离得到的4种不同AM真菌物种，1组接种这4种真菌的混合群落，另有1组为未接种的对照组。接种AM真菌的方式为：在重复设置的样地中定植16株经AM真菌侵染的保育植物。同时，我们使用包含54个物种的多样化原生草原种子组合对修复样地进行播种。 研究结果显示，AM真菌接种显著驱动植物群落组成结构：接种特定AM真菌处理的样地以优质原生草原植物为优势类群，而接种其他AM真菌物种的样地及未接种对照组，则以杂草、外来物种等劣质植物为优势类群。具体而言，多数演替早期物种的定植效果不受AM真菌接种与否的影响；而多数演替后期物种的定植与生长则高度依赖特定AM真菌类群的存在。若无AM真菌接种，许多保守型演替后期物种均无法存活定植。整体而言，经AM真菌接种的样地中，植物群落总丰富度、多样性及植物区系质量指数（Floristic Quality Index, FQI）均得到显著提升；而未接种对照组的劣质植物丰度则显著更高。 综合与应用。本研究结果表明，诸多既往修复研究中报道的演替后期物种定植失败问题，可能源于这些样地中丛枝菌根真菌群落功能失效。我们认为，从原生参考草原环境中重新引入丛枝菌根真菌，可通过提升植物多样性与丰富度——尤其针对优质演替后期植物物种——同时抑制劣质杂草类植物，从而改善草地修复效果。