## 1 Introduction  
The ecological environment constitutes the material foundation for human survival, serves as the base and core of regional social economic development, and interacts closely with historical development processes [1]. However, the pace of modernization has exerted significant stress on ecosystems. Consequently, objective, scientific, and timely assessments of ecological quality have become critical for effective monitoring of ecological conditions and the sustainable management of natural resources. This also aids in advancing environmental protection and sustainable economic prosperity [2]. Since the 1960s, researchers have explored the evaluation of ecological environment quality, shifting from single-factor surveys to multifaceted evaluations [3]. Advances in remote sensing technology have facilitated the rapid acquisition of a wide range of ecological indicators, surpassing the constraints of traditional manual monitoring, and have been of widespread use in ecological and environmental research [4]. While many studies utilize remote sensing technology to extract indicators such as the Normalized Difference Vegetation Index (NDVI) [5], the Normalized Difference Water Index (NDWI) [6], and the Land Surface Temperature (LST) [7], these singular metrics are insufficient for capturing the complexity of ecological environments. Subsequently, [PERSON] [8] proposed the Remote Sensing Ecological Index (RSEI), which provides an objective evaluation of regional ecological quality across four dimensions: greenness, wetness, heat, and dryness. RSEI's comprehensive and semi-automatic approach has been successfully implemented and validated in various regions, including those of watersheds [9; 10; 11], urban areas [12], and mining zones [13], yielding favorable results. The Qinling Mountains serve as a natural boundary separating the climatic, biological, hydrological, pedological, and geological elements of northern and southern China, playing a vital role in the nation's ecological stability. The forest ecosystem of the Qinling Mountains is pivotal for water conservation, biodiversity preservation, and soil erosion control [14]. The ecological condition here is also crucial for the water supply of the South-to-North Water Diversion Project, significantly impacting the ecological civilization construction and socioeconomic development of the Yangtze and Yellow River basins [15]. Consequently, protecting the Qinling's ecological environment is essential for the ecological security of the nation and surrounding regions [16]. However, frequent human activities have caused significant ecological problems in the Qinling Mountains, including deforestation, soil erosion, and geological disasters [17]. In particular, the extensive illegal construction on the Qinling's northern slopes in Shaanxi province has negatively impacted the area's ecological functions [18]. In response, the Shaanxi government has enforced various ecological protection measures, such as natural forest protection and the Grain for Green (GFG) project, aiding in the ecosystem's recovery [19]. Therefore, investigating the patterns and spatial distribution of changes in the ecological environment quality of the Qinling Mountains as well as analyzing the key drivers behind these changes is crucial for a comprehensive understanding of Qinling's distinct geographic significance. Moreover, extracting and quantifying these drivers is essential for assessing the enduring impact of human activities on the ecosystem in the context of global warming. Recent studies have applied remote sensing technology to investigate vegetation cover, net primary productivity, and land use changes in the Qinling area [16; 20; 21]. Specifically, from 2000 to 2020, the vegetation coverage on the east and west sides of the Qinling remained consistently lower than that in the central areas, yet there was an overall trend of continuous improvement [22].