Stable carbon isotope technology can indicate the material cycle and energy flow of ecosystem. According to the carbon transfer dynamics of ecosystem, the carbon cycle process and carbon fixation capacity of ecosystem can be explored. Artemisia halodendron, Caragana microphylla and Salix gordejevii Chang, as well as Phragmites australis and Zea mays Linn, which are widely distributed in the meadow, were selected as the research objects. The characteristics of atmosphere, leaves, litter and soil continuum δ¹³C value at the canopy of each vegetation community, the distribution characteristics of carbon content and the relationship between components were analyzed. The results showed that the atmospheric CO₂ concentration in the canopy of dune vegetation was significantly lower than that of meadow vegetation, which was controlled by the characteristics of soil moisture and plant growth. Under stress, Caragana microphylla leaves had the highest water use efficiency and the lowest cost of carbon sequestration and water consumption. Leaf carbon content and δ¹³C value both were affected by the growth period of leaves. The potential carbon storage capacity of new leaves was stronger and the water use efficiency was higher. There were significant differences in leaf litter δ¹³C value among different vegetations, indicating the driving role of plant functionality. With the increase of soil depth, organic matter decomposed completely and the content of soil organic carbon decreased, δ¹³C value showed a positive trend. Dune soil δ¹³C value was higher than that of meadow, the turnover rate of soil organic carbon in dune was higher than that of meadow, and the soil type had a great impact on the turnover of organic carbon. It is helpful to deeply understand the key process of carbon cycle in sandy meadow alternating areas, and provides a theoretical basis for desertification control.