The urban belt along the Yellow River in Ningxia, located in the middle and upper reaches of the Yellow River, serves as the population and economic center of Ningxia. Quantitatively analyzing the spatiotemporal distribution characteristics of the fraction of vegetation cover （FVC） in this region and its driving factors is of great significance for promoting ecological protection and the construction of a leading area for high-quality development in the Yellow River Basin. In this study, Landsat satellite remote sensing data were utilized to derive the vegetation cover from 2001 to 2020 in the cities along the Yellow River in Ningxia using a pixel-based binary model. The spatial pattern and spatiotemporal changes were analyzed. Additionally, meteorological data and topographic information for the same period in this region were combined. Sen+Mann-Kendall trend analysis, Hurst index, and parameter-optimized geographical detector models were used to analyze the driving factors. The results indicated： ① From 2001 to 2020, there was a significant overall increasing trend in vegetation cover in the urban belt along the Yellow River in Ningxia （P<0.01）, with a growth rate of 0.25% per annum. The 20-year average FVC was 33.38%, and the vegetation cover was at a relatively low level. In terms of spatial distribution, the vegetation was high in the northeast and low in the southwest, and the main types were very low vegetation coverage and low vegetation coverage. ② During the 20 years, the vegetation condition of the urban belt along the Yellow River in Ningxia had been significantly improved, and the portion of the area with improved vegetation cover accounted for 62.60%, which was much larger than that of the degraded area, and the average coefficient of variation of FVC was 0.098, which was good for the overall stability. ③ The area with H value of FVC less than 0.5 accounted for 66.15%, which showed strong anti-continuance, the area of FVC with improving trend accounted for 34.84%, the area of continuously stable and unchanged area accounted for 7.8%, the area with degrading trend accounted for 52.9%, and the future trend of FVC was uncertain in 9.0% of the area. ④ The analysis of driving factors revealed that land use type was the primary factor influencing the spatial distribution of vegetation cover in the urban belt along the Yellow River in Ningxia. The explanatory power （Q value） of interactions among various factors was higher than that of individual factors, demonstrating synergistic and nonlinear relationships among them, with no independent relationships. Risk detection showed that each driving factor had its appropriate range for impacting vegetation growth in the study area.
Keywords: OPGD model; driving factors; fractional vegetation coverage（FVC）; spatiotemporal variation; trend analysis.