草地土壤碳氮磷含量及其生态化学计量的空间变异关系到草地生态系统的功能与稳定性。海拔、气候、土壤性质和植被如何影响新疆北部典型牧区额尔齐斯河（简称额河）流域土壤碳氮磷化学计量的空间格局尚不清楚。本文选取了额河流域六种主要草地类型的65个样点（0~10 cm、10~20 cm土层）进行研究。结果表明：（1） 高寒草甸、山地草甸、温性草甸草原有机碳（39.06~62.59 g·kg^-1）、总氮含量（3.87~6.95 g·kg^-1）以及六种草地类型的土壤总磷含量（0.53~1.59 g·kg^-1）总体上高于中国土壤平均值（24.56 g·kg^-1、1.88 g·kg^-1、0.56 g·kg^-1），而六种草地类型的土壤碳氮比（5.03~9.97）、碳磷比（7.50~52.38）以及温性草原、温性荒漠草原和温性荒漠土壤氮磷比（1.53~3.72）低于中国或全球土壤平均值（11.40、64.30、3.90）。（2） 土壤碳氮磷含量以及碳磷比、氮磷比随着海拔升高（328~2655 m）、降水量增加以及温度降低而显著增加，并且与植被特征、土壤理化性质有显著的相关性。随着海拔的升高，土壤有机碳、总氮含量与土壤碳磷比在土层间的差异逐渐增加。（3） 结构方程模型结果表明，海拔与气候因子对土壤碳氮磷含量及其生态化学计量的影响效应最高，海拔通过改变温度、降水、植被特征、土壤理化性质影响土壤碳氮磷含量，最终影响生态化学计量。未来应进一步开展气候变化对土壤碳氮磷及其生态化学计量影响的跨区域尺度研究。

Spatial variations in soil carbon, nitrogen, and phosphorus concentrations, as well as their ecological stoichiometry, in grasslands are related to the function and stability of grassland ecosystems. The Irtysh River Basin exhibits a significant disparity in altitude, remarkable climate variation, and diverse grassland types that display a vertical zonal distribution. Nevertheless, there are no clear data on the influence of altitude, climate, soil properties, and vegetation on the spatial patterns of soil carbon, nitrogen, and phosphorus stoichiometry in the Irtysh River Basin, which is a typical pastoral area in Xinjiang. Therefore, this study investigated 65 sample points from six main grassland types (temperate desert, temperate desert steppe, temperate steppe, temperate meadow steppe, mountain meadow, and alpine meadow) in the Irtysh River Basin at depths of 0-10 and 10-20 cm. The following results were obtained: (1) The soil organic carbon (39.06-62.59 g·kg^-1), total nitrogen (3.87-6.95 g·kg^-1), and total phosphorus (0.53-1.59 g·kg^-1) concentrations of alpine meadow, mountain meadow, and temperate meadow steppe were higher than the average concentrations of Chinese soil. However, the soil C:N (5.03-9.97) and C:P (7.50-52.38) ratios, as well as the soil N:P (1.53-3.72) ratios of temperate steppe, temperate desert steppe, and temperate desert, of the six grassland types were lower than the average ratios of Chinese soil (2) The concentrations of soil carbon, nitrogen, and phosphorus, as well as the C:N and C:P ratios, increased significantly with increasing altitude (328-2655 m) and precipitation and decreasing temperature. These parameters also exhibited significant correlations with soil physicochemical properties and vegetation characteristics. With increasing altitude and precipitation and decreasing temperature, the differences in soil carbon and nitrogen concentrations and soil C:P ratios gradually increased among soil layers. (3) The structural equation model revealed that altitude and climate exerted the highest impact on soil carbon, nitrogen, and phosphorus concentrations, as well as on their ecological stoichiometry. Altitude affected soil carbon, nitrogen, and phosphorus concentrations by changing the temperature, precipitation, vegetation characteristics, and soil physicochemical properties, ultimately affecting ecological stoichiometry. Future research should further explore the impact of climate change on soil carbon, nitrogen, and phosphorus concentrations, as well as on their ecological stoichiometry, at a regional scale. This study provides basic data and a theoretical basis for estimating soil nutrient storage, as well as for protecting and utilizing grassland ecosystems in the Irtysh River Basin.