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本研究把怀俄明州切恩附近高地４０年没有放牧的草场，采用三种管理制度，经过强度放牧（放牧６７天／ｈｍ２） １１年后，与连续轻度放牧（放牧２２天／ｈｍ２）和禁止放牧进行了比较。强度放牧时，年产草量的利用率不到５０％，与土地管理部门提出的水平相当。通过采集９１ｃｍ深的土样，来评估土壤有机碳、氮的变化，与禁牧区相比，放牧区地表下３０ｃｍ土壤的碳、氮含量比较高，而在３０ｃｍ以下土层，各种放牧条件下土壤的碳、氮含量相差不大。 ３／４的植物根部生物量存在于地表下３０ｃｍ的土层，该土层内的碳、氮活力最强。过去的１１年里，在这块混合大草原上采用各种放牧制度和放牧强度对土壤的有机碳、氮没有产生有害影响。该研究表明，用这些参数进行评估，合理放牧会全面提高土壤质量。
In this study, we used three management systems of grazing pastures in Cheyenne, Wyoming, in the past 40 years, after 11 years of intensive grazing (grazing 67 days / hm2) and continuous mild grazing (grazing 22 days / hm2) Grazing was compared. Intensity grazing, the annual yield of less than 50% utilization rate, and the level of land management departments proposed. Soil organic carbon and nitrogen change were evaluated by collecting soil samples of 91cm depth. Compared with the no-grazing areas, the 30cm soil layers in the grazing area had higher carbon and nitrogen contents. Under the condition of 30cm soil layers and grazing conditions Soil carbon, nitrogen content is not much difference. Three-fourths of the plant’s root biomass existed in the soil layer 30 cm below the surface, with the strongest carbon and nitrogen in the soil layer. Over the past 11 years, the use of various grazing systems and grazing intensities on this mixed steppe has had no detrimental effect on soil organic carbon and nitrogen. The study shows that using these parameters for assessment, reasonable grazing can improve soil quality overall.