Abstract: This study was to explore the effects of different grass-soil feedback on soil nutrients and microbial community structure composition and function of Pedicularis kansuensis. In this study, four grasses were used as materials. The soils from the plant patch of P. kansuensis were used as culture substrates. A pot experiment was conducted to study the effects of grass growth on soil nutrients and microbial community composition of P. kansuensis. Functional annotation analysis was conducted on fungal and bacterial communities by using FUNGuild and FAPROTAX tools,respectively. The results showed that compared with the blank control,the growth of different grasses increased soil pH and ammonium nitrogen content,significantly reduced available potassium and nitrate nitrogen content,and had no significant difference in organic matter content. The plant height,carbon,nitrogen,potassium content,diversity index,and relative abundance of soil fungal and bacterial communities of different grasses growing in the soil of the P. kansuensis community vary depending on the type of grass. Different grass growth has a direct impact on grass nutrients,soil nutrients and microbial communities. The feedback effects of grass nutrients,soil nutrients and microbial communities have an impact on grass biomass. The results of this study can provide a scientific basis for the improvement of degraded grasslands and the management of artificial grasslands with P. kansuensis as the dominant species.

Key words: Grass species, Grass-soil feedback, Soil nutrients, Microbial community

摘要： 为探讨不同禾草-土壤反馈对甘肃马先蒿(Pedicularis kansuensis)群落土壤养分及微生物群落结构组成和功能的影响，本研究以4种禾草为材料，以甘肃马先蒿为主的退化草地植物群落土壤为栽培基质，通过盆栽控制试验，分析了禾草生长对甘肃马先蒿土壤养分和微生物群落组成的影响，并采用FUNGuild和FAPROTAX工具分别对真菌和细菌群落进行功能注释分析。结果表明：与空白对照相比，不同禾草生长提高了土壤pH及铵态氮含量，使速效钾和硝态氮含量显著降低，有机质含量无显著差异。不同禾草在甘肃马先蒿土壤中生长的株高、禾草碳、氮、钾含量、土壤真菌和细菌群落的多样性指数、相对丰度因禾草种类而异。不同禾草生长对禾草养分、土壤养分和微生物群落产生直接影响，禾草养分、土壤养分和微生物群落反馈作用对禾草生物量产生影响。本研究以期为甘肃马先蒿为优势种的退化草地改良和人工草地管理提供科学依据。

关键词: 禾草种类, 禾草-土壤反馈, 土壤养分, 微生物群落