Soil organic matter is crucial for soil health and sustainability in mountainous areas near Beijing. By studying 165 soil samples, researchers found that soil organic carbon content is influenced by altitude, vegetation, and humidity. Higher altitudes and better vegetation lead to more organic matter in the soil. Organic carbon decreases from the surface to deeper layers, with different rates depending on the type of vegetation cover. Farming soil has less organic carbon variability compared to natural soil, with grasslands showing the most variability. This information is important for protecting mountainous soil and guiding development in these areas.