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Ecological source areas play a pivotal role in nature preservation and soil conservation. These areas are critical in optimizing land-use patterns and fostering the establishment facilitating the establishment of protected ecological source areas. In this study, two types of state layers of ecological source area change were extracted based on land cover data and integrated with an intelligent algorithm to analyze the role of ecological factors contributing to land change. Recommendations are proposed to enhance the optimization of the ecological spatial pattern within the Yellow River Basin. The results indicate key findings: (1) The ecological source areas in the Daxia River Basin experienced Fluctuations between 1990 and 2020 due to the interconversion of grassland and unused land. The change was relatively smooth during 1990–2000, with the ecological source areas increasing slightly by 16.016 km2. From 2000 to 2010, the proportion of unutilized land transferred to grassland was 6.3%, which is significantly higher than the annual transfer average of 1.6%. This is mainly due to the ecological protection measures in the cities of Linxia and Hezuo. Between 2010 and 2020, economic construction resulted in the loss of grassland, and the percentage of grassland turned out was 7.3%, which was significantly higher than the annual average of 1.8%. (2) In the Daxia River Basin, rainfall, sunlight intensity, temperature, and elevation had a greater impact on land change during the period from 1990 to 2020, with contributions of −0.4, 0.09, 0.08, and −0.26, respectively. [ABSTRACT FROM AUTHOR]

We experimentally investigate trap-loss spectra of the cesium 6S1/2(F = 4) → 71P3/2 Rydberg transition by combining the cesium atomic magneto-optical trap with the narrow-linewidth, continuously tunable 318.6 nm ultraviolet laser. Specifically, the atoms in the magneto-optical trap are excited to the Rydberg state due to the ultraviolet laser single-step Rydberg excitation, which leads to the reduction of atomic fluorescence. Based on the trap-loss spectroscopy technology, the Autler–Townes (AT) splitting due to a strong cooling laser is observed, and the parameter dependence of the AT splitting interval of trap-loss spectroscopy is investigated. The effective temperature of cold atoms is measured by using simplified time-of-flight fluorescence imaging. In addition, closed-loop feedback power stabilization of 318.6 nm ultraviolet laser is carried out. This lays the foundation for further experimental research related to the Rydberg atoms using ultraviolet lasers, which is of great significance for the development of quantum computing and quantum information. [ABSTRACT FROM AUTHOR]