青藏高原是我国乃至全球重要的土壤有机碳库和无机碳库，其碳含量分布对全球气候调节以及区域碳循环具有重要影响。近年来，已有许多研究主要集中在从流域和区域尺度揭示青藏高原地区土壤碳分布特点，而对坡面土壤有机碳和无机碳空间分布的研究还相对薄弱。因此，本研究选取高寒半干旱区青海湖流域季节性冻土区阴、阳坡土壤为研究对象，通过野外调查、样品采集和室内化验分析，研究了不同坡面土壤理化性质、不同坡面土壤有机碳和无机碳分布特征，同时探讨了土壤各理化性质对土壤有机碳和无机碳含量空间分布特征的影响。研究结果有助于深入认识高寒地区较小尺度下的土壤碳分布变异特性，可为高寒季节性冻土区土壤碳水过程及较大尺度土壤碳储库研究提供参考和依据。主要研究结果如下：

（1）不同坡向，土壤有机碳和无机碳空间分布差异显著。土壤有机碳平均含量表现为阴坡（81.99 g/kg）＞阳坡（61.84 g/kg），土壤无机碳平均含量表现为阴坡（0.61 g/kg）＜阳坡（3.61 g/kg）。各坡向土壤有机碳含量均随土层深度增加而呈降低趋势，但阳坡下降的幅度（64%）明显高于阴坡（44%）；其中阴坡0—20 cm土层所含的土壤有机碳含量占0—50 cm土层的59.55%，阳坡0—20 cm土层所含的土壤有机碳含量占0—50 cm土层的66.74%。土壤无机碳含量均随土层深度增加而增加，其中阴坡30—50 cm土层所含的土壤无机碳含量占0—50 cm土层的64.27%，阳坡30—50 cm土层所含的土壤无机碳含量占0—50 cm土层的56.24%。

（2）不同坡位，土壤有机碳和无机碳含量分布均因坡向而异。土壤有机碳平均含量在阴坡表现为坡下（89.60 g/kg）＞坡中（86.52 g/kg）＞坡上（69.87 g/kg），在阳坡表现为坡上（65.71 g/kg）＞坡下（61.42 g/kg）＞坡中（58.39 g/kg）。土壤无机碳平均含量在阴坡表现为坡中（0.71 g/kg）＞坡上（0.60 g/kg）＞坡下（0.54 g/kg），在阳坡表现为坡下（4.10 g/kg）＞坡中（3.95 g/kg）＞坡上（2.77 g/kg）。坡位对不同深度土壤有机碳和无机碳的影响程度存在差异。阴坡坡位对深层土壤有机碳影响显著，而阳坡坡位对浅层土壤有机碳影响显著。无论是阴坡还是阳坡，坡位对不同深度土壤无机碳的影响程度均表现为对深层土壤的影响大于浅层。

（3）土壤有机碳含量与土壤无机碳含量呈显著的指数负相关关系。土壤有机碳的影响因素主要是pH和容重，其中pH值解释了72.67%的变异性，容重解释了14.81%的变异性。土壤无机碳的影响因素主要是pH和含水量，其中pH值解释了69.73%的变异性，土壤含水量解释了11.16%的变异性。

The Qinghai-Tibet Plateau is an important soil organic carbon pool and inorganic carbon pool in China and even around the world, and its carbon content distribution has significant influence on global climate regulation as well as regional carbon cycle. In recent years, many studies have mainly focused on the distribution characteristics of soil carbon in Qinghai-Tibet Plateau area at the watershed and regional scale, while the study on the spatial distribution of the soil organic carbon and inorganic carbon at slope scale is relatively scarce. Therefore, this paper studied the soil of shady and sunny slopes in seasonally frozen area of Qinghai Lake basin in alpine and semi-arid region. Through field investigation, sample collection and lab test analysis, the physical as well as chemical properties of soil in different slopes and distribution characteristics of the soil organic carbon and inorganic carbon in different slopes were studied, and also the influence of physical and chemical properties of soil on spatial distribution of the soil organic carbon and inorganic carbon was discussed. The research results are conducive to further understanding the variation characteristics of soil carbon distribution at a small scale in alpine regions, and will provide scientific basis for the study of soil carbon and water processes and soil carbon pools at a large scale in alpine seasonally frozen areas.The main findings were as follows:

 (1) The distribution characteristics of SOC and SIC content were significantly different in different slope aspects. The average SOC content on the shady slope was 81.99 g/kg, higher than that of the sunny slope (61.84 g/kg). While, the average SIC content on the sunny slope (3.61 g/kg) was higher than that of the shady slope (0.61 g/kg). The SOC content of both shady and sunny slopes decreased with the increase of soil depths, but the decrease range of the sunny slope (64%) was significantly higher than that of the shady slope (44%). The SOC content was mainly concentrated in the 0—20 cm soil layer, which on the shady slope and the sunny slope accounted for 59.55% and 66.01% of the 0—50 cm soil layer respectively. The SIC content of both shady and sunny slopes increased with the increase of soil depths. The SIC content was mainly concentrated in the 30—50 cm soil layer, which on the shady slope and the sunny slope accounted for 64.27% and 56.24% of the 0—50 cm soil layer respectively.

 (2) The distribution characteristics of SOC and SIC content in different slope positions varied with slope aspects. On the shady slope, the average SOC content showed a trend of lower slope (89.60 g/kg) > middle slope (86.52 g/kg) > upper slope (69.87 g/kg); the average SIC content showed a trend of middle slope (0.71 g/kg) > upper slope (0.60 g/kg) > lower slope (0.54 g/kg). While on the sunny slope, the average SOC content tended to be upper slope (65.71 g/kg) > lower slope (61.42 g/kg) > middle slope (58.39 g/kg); the average SIC content showed a trend of lower slope (4.10 g/kg) > middle slope (3.95 g/kg) > upper slope 2.77 g/kg). In addition, the effect of slope positions on SOC and SIC content at different depths also varied in different slope aspects. The shady slope factor had a significant effect on SOC content at deep soil layers, and the sunny slope factor had a significant effect on SOC content at shallow soil layers. While both the shady and sunny slopes factor had a significant effect on SIC at deep soil layers.

 (3) SOC and SIC content presented a significant negative exponential correlation. The main influencing factors of the SOC content are pH and bulk density, in which pH explained 72.67% variability and the bulk density explained 14.81% variability. The main influencing factors of the SIC are pH and bulk density, in which pH explained 72.67% variability and the bulk density explained 14.81% variability.