This study examines the influence of rocky desertification and other commonly observed factors on ecosystem quality. This research takes Guizhou Province, the region most severely affected by rocky desertification in China, as a case study and assesses ecosystem quality using the improved remote sensing ecological index (DRSEI). Additionally, the remote sensing rocky desertification index (RSRI) was applied to evaluate the severity of rocky desertification in the region. Finally, the optimal-parameter geographical detector was used to analyze the effects of rocky desertification and other variables on ecosystem quality. The results indicated that the ecosystem in Guizhou Province followed a "degradation-recovery" evolutionary trend throughout the study period. The improvement in ecosystem quality outpaced the progress of rocky desertification control. However, there was a notable lag in the effectiveness of mitigation efforts. The optimal-parameter geographical detector further revealed that the rocky desertification index (RSRI) consistently served as the dominant factor explaining variations in ecosystem quality. However, its dominant role gradually diminished over time. Moreover, although the RSRI showed strong interactions with other variables, its synergistic influence also declined somewhat. This indicates a shift in the ecosystem's driving mechanism from "rocky desertification dominance" to "multi-factor coordination." These findings suggest that rocky desertification should remain a priority in initiatives aimed at enhancing ecosystem quality in Guizhou Province. Furthermore, the interactions between the RSRI and other factors, such as temperature and precipitation, should be carefully considered to improve the effectiveness of desertification control efforts.