宁夏典型草原土壤微生物特征对不同管理方式的响应

草地土壤微生物是土壤养分循环的推动力，可灵敏反映草地生态环境变化，常被用来评价草地土壤质量。本研究以宁夏典型草原为对象，研究了封育、放牧和水平沟改良管理方式下土壤微生物特征及其与土壤有机质的相关性。结果表明，试验区0~40 cm土层土壤微生物数量表现为细菌>放线菌>真菌；细菌和放线菌数量随封育年限增加呈增加趋势，真菌以封育5年草地最高；微生物总数量和微生物量碳、氮含量均表现为随封育年限增加而增加，放牧草地最低；水平沟改良草地微生物特征未表现出明显的优越性；土壤微生物数量表现为5~15 cm土层最高，25~40 cm土层最低；土壤微生物数量与有机质含量之间存在极显著正相关关系。

Responses of soil microbial prosperities to different management modes in typical steppe, Ningxia

Soil microorganism community of grassland is a driver of soil nutrient cycle,which can sensitively reflect changes of ecological environment of grassland,and is always looked as an indicator for soil quality.Present study was conducted on the typical steppe grassland in Ningxia to investigate soil microorganism properties and the relationship between microorganism properties and soil organic content under different management modes including enclosure,grazing and horizontal ditch.The results showed bacteria amount>actinomyces amount>fungus amount in 0-40 cm soil depth of research area.Bacteria and actinomyces number increased with enclosure time increasing.Fungus amount in grassland enclosed for 5 years was the highest in all treatments.The total amount of microorganism,microbial biomass carbon,and nitrogen increased with the increasing of enclosure time,and were the lowest in grazing grassland.There was no advantage of microorganism properties in horizontal ditch grassland.In different soil layers,the highest microorganism amount was observed in 5-15 cm soil depth,and the lowest amount was found in 25-40 cm soil depth.There was a significantly positive relationship between microorganism amount and soil organic content.