Monitoring and assessment of the resource and environmental carrying capacity in the Gannan Yellow River source area

The Gannan Yellow River source area (YRSA) is a typical ecological fragile region. Assessing the temporal and spatial patterns of resource and environmental carrying capacity (RECC) is crucial for both ecological security and sustainable development of the Yellow River Basin and the YRSA. Based on RECC theory, this study developed a novel index system focused on human-livestock-grassland relationships to accurately capture resource and environmental carrying characteristics in pastoral regions. By establishing region-specific evaluation thresholds and using a comprehensive index approach, we analyzed spatial and temporal patterns of resource carrying capacity (RCC), environmental carrying capacity (ECC), and resource and environmental carrying capacity (RECC) in the Gannan region from 2005 to 2020. The results indicate that: 1) The RECC followed an increasing–decreasing–increasing trajectory from 2005 to 2020, with values ranging from 0.30 to 0.69. The RECC in pastoral areas was not only higher but also exhibited greater variability compared to that in agricultural areas. 2) The RCC remained at a low level, with values between 0.06 to 0.098. The index of water consumption per ten thousand Yuan of GDP increased significantly, suggesting that improvements in water use efficiency contributed to the enhancement of RCC. 3) The ECC increased notably, shifting from the middle to a very high level, with values ranging from 0.233 to 0.611. ECC emerged as a key determinant of RECC, exhibiting a temporal trend closely aligned with that of RECC. Changes in ECC were primarily driven by factors such as overgrazing rates, the extent of grassland rodent control, and the area of grassland for reseeding and improvement. Based on these findings, future priorities should include the adoption of efficient water-saving irrigation technologies, the promotion of rotational grazing practices, and the optimization of land management strategies.