Abstract: Improvement measures are essential for promoting the ecosystem restoration of degraded grasslands. In order to assess the effectiveness of composite improvement measures on the degraded meadow grasslands in Hulun Buir， this study evaluated four treatments： root cutting+organic fertilizer+microbial agent （YQJ）， root cutting+organic fertilizer （YQ）， root cutting+foliar fertilizer （YY）， and a control group （CK）. The results demonstrated that compared to the control， all three improvement measures enhanced plant community height， coverage， and biomass. Among these， the root cutting+foliar fertilizer treatment exhibited the most significant effect （P<0.05）， resulting in a 70% increase in aboveground biomass relative to the control. Notably， fertilization treatments resulted in a reduction of plant community diversity. The composite improvement measures positively influenced soil conditions in the degraded grasslands： the root cutting+foliar fertilizer treatment significantly elevated the levels of total phosphorus， total potassium， available phosphorus， and available potassium in the soil， whereas root cutting+organic fertilizer+microbial agent treatment markedly enhanced soil ammonium nitrogen and nitrate nitrogen content （P<0.05）. These findings indicated that the improvement measures had positively impacted the soil conditions of the degraded grasslands， leading to a notable increase in grassland productivity， with the root cutting+foliar fertilizer treatment demonstrating superior improvement effects.

Key words: Root cutting, Fertilization, Degraded meadow grassland, Plant community, Soil nutrient

摘要： 改良措施对促进退化草地生态系统恢复至关重要，本研究设置切根+有机肥+微生物菌剂（YQJ）、切根+有机肥（YQ）、切根+叶面肥（YY）、对照（CK）4种处理，探究复合改良措施对呼伦贝尔退化草甸草原的改良效果。结果表明：相较于CK，3种改良措施均能提高植物群落高度、盖度和生物量，其中切根+叶面肥处理改良效果最显著（P<0.05），地上生物量较对照提高70%；施肥处理会导致植物群落多样性下降；复合改良措施对退化草地土壤具有正向调控作用，切根+叶面肥处理显著增加土壤全磷、全钾、速效磷和速效钾含量，切根+有机肥+微生物菌剂处理显著提高土壤铵态氮和硝态氮含量（P<0.05）。这说明在改良措施的影响下，退化草地的土壤条件得到改善，草地生产力明显增强，且以切根+叶面肥处理改良效果更佳。

关键词: 切根, 施肥, 退化草甸草原, 植物群落, 土壤养分