为了揭示西藏高原高寒草原生态系统植被碳磷比的分布特征及其影响因素，以西藏高原高寒草原生态系统为对象，采用野外调查与室内分析相结合的方法，对高寒草原生态系统植被碳磷比的分布特征及其影响因素进行研究。结果表明：西藏高原高寒草原19个草地型植物叶片碳磷比的平均值为204.53，变异系数为35.72%，植物根系碳磷比的平均值为226.29，变异系数为27.93%，总体呈现出东西部低、中间高的态势和斑块状交错分布的格局。影响植物叶片碳磷比的关键环境因子是年均气温、最冷月均气温、≥10℃积温、6—9月降水率、0~10 cm土壤容重、10~20 cm土壤含水量、土壤速效钾、水溶性碳、全氮、全磷和全钾含量；而影响根系碳磷比的关键环境因子则是最冷月均气温、≥10℃积温、年均降水量、地上生物量、土壤pH、有机质、全钾、全磷和总碳水化合物含量。

In order to reveal the distribution characteristics and influence factors of alpine steppe ecosystem vegetation C/P in Tibetan plateau, taking alpine steppe ecosystem in Tibetan Plateau as the abject, the vegetation C/P distribution characteristics and its influence factors were researched, based on the methods of field investigation combining with laboratory analysis. The results showed that: the average leaf N/P of 19 grassland type plants of alpine steppe in Tibetan Plateau was 204.53, the coefficient of variation (CV) was 35.72%. And the average root system C/P was 226.29, the CV was 27.93%. N/P appeared lower in east and west and higher in the middle part of Tibetan Plateau as a macrocosm tendency with distribution characteristics of staggered pattern. The key environmental influence factors of plant leaves C/P were: average annual temperature, average temperature in the coldest month, precipitation during the period from June to September, soil bulk density of depths from 0 cm to 10 cm, soil water content of depths from 10 cm to 20 cm, soil content of available K and water-soluble carbon and total nitrogen and total N, P and K. And the key environmental influence factors of plant roots C/P were average temperature in the coldest month, ≥10℃ accumulated temperature, average annual precipitation, aboveground biomass production, soil pH, soil organic matter and soil content of total K, P and carbohydrate.