Identifying carbon sequestration's priority supply areas from the standpoint of ecosystem service flow: A case study for Northwestern China's Shiyang River Basin

Finding important supply areas helps maintain the ecological security of the region and promotes the creation of healthy ecosystems. By considering the ecosystem service flows (ESF), priority provisioning area studies can be approached from a new perspective. This study describes the real supply in terms of flows. The goal was to reveal the priority-ranked supply pattern of ecosystem carbon sequestration services (ECSS) in the Shiyang River Basin (SRB). First and foremost, soil respiration models and Carnegie-Ames-Stanford Approach (CASA) model were used to examine the supply of ECSS, and a combination of natural and human factors was used to determine the demand for ECSS. Second, Python was used to illustrate the ECSS flow trajectories and flows. Lastly, and utilized in conjunction with System Conservation Planning (SCP) to determine supply regions of importance. The results show that, first, the spatial distribution of ECSS supply and demand clearly demonstrates heterogeneity. This is reflected in the spatial characteristics of supply, which are "high in the south and low in the north," and demand, which is "high in the urban areas and low in the suburbs." Second, the middle and lower portions of the basin, where there is little precipitation and little vegetation, are home to the majority of the locations with poor carbon sequestration fluxes. These areas accounted for almost 60 % of the entire watershed area over time. Third, the first priority area of ECSS occupies 19.3 % of the basin's total area, while the second priority area occupies 21.46 %. For the major supply regions, strict ecological protection laws must be implemented going forward in order to ensure the ability to sustain ECSS supply. The long-term growth of SRB as well as ecological and environmental management can benefit from this research's foundational role in policymaking.