氮、磷添加对青藏高原高寒草甸丛枝菌根真菌群落的影响

【目的】探究青藏高原高寒嵩草草甸生态系统中丛枝菌根真菌(AMF)群落对氮、磷添加的响应及其驱动因子,补充目前高寒草甸AMF对施肥响应研究的不足。【方法】通过常规分析和高通量(Illumina-Miseq)测序,分析氮(0、7.5、15.0 g·m~(-2))、磷(0、7.5、15.0、30.0 g·m~(-2) P_2O_5)添加3年对青藏高原高寒小嵩草草甸土壤化学性质、AMF侵染率、OTU丰度、 Shannon多样性指数和AMF群落组成的影响。【结果】测序共发现36个AMF的OTU,归属于7个科。氮、磷的添加及其交互作用对AMF侵染率、OTU丰度和Shannon多样性指数均无显著影响。相对于低施氮处理,高施氮处理显著降低球囊霉门的相对丰度。土壤有机碳、硝态氮、有效磷和全磷含量均是影响AMF群落的土壤因子。【结论】青藏高原高寒嵩草草甸根系AMF群落不受氮、磷添加的影响,群落分布与土壤因子有显著相关性。

Effects of nitrogen and phosphorus additions on arbuscular mycorrhizal fungi community in the alpine meadow in Qinghai-Tibetan plateau

Objective To investigate the responses of arbuscular mycorrhizal fungi (AMF) community to nitrogen and phosphorus additions and the driven factors in the Qinghai-Tibetan alpine meadow, and have a better knowledge of the effects of fertilization on alpine meadow AMF community.Method Through regular analyses and high-throughput sequencing (Illumina Miseq), we studied the effects of nitrogen addition (0, 7.5, 15.0 g·m^-2) and phosphorus addition (0, 7.5, 15.0 and 30.0 g·m^-2 P₂O₅) for three year on soil chemical property, AMF colonization rate, OTU richness, Shannon diversity index and AMF community composition in Qinghai-Tibetan alpine meadow.Result The 36 AMF OTUs from seven families were detected. The addition of nitrogen, phosphorus and their interaction had no influence on AMF colonization rate, OTU richness and Shannon diversity index. Compared with low nitrogen addition treatment, high nitrogen input treatment significantly decreased the relative abundance of Glomeraceae. Soil organic carbon, nitrate nitrogen, available phosphorus and total phosphorus contents were the factors which impacted AMF community.Conclusion Root AMF community in Qinghai-Tibetan alpine Kobresia meadow wasn''t affected by nitrogen or phosphorus addition. However, the distribution of community was significantly correlated with edaphic factors.