The Shendong mining area is the largest coal production base in western China. Due to long-term mining activities, the ecological environment quality (EEQ) of the Shendong mining area has undergone significant changes. Investigating the evolution of EEQ during the process of mineral resource exploitation is of great importance for the sustainable development of the mining area. However, current research lacks a quantitative assessment of the contributions of climate change and human activities to the spatiotemporal variations in EEQ in the Shendong mining area. In this study, the Remote Sensing Ecological Index (RSEI) was used as an EEQ evaluation metric. The Theil–Sen slope estimation and Mann–Kendall test were applied to analyze the spatiotemporal changes of EEQ from 1990 to 2023. Additionally, the partial derivative method was used to investigate the response characteristics of EEQ to climatic factors and human activities and to quantify the relative contributions of these two driving factors. The results indicate that, over the past 34 years, the overall EEQ in the study area has shown an improving trend. Compared to 1990, the proportions of areas with good-grade and excellent-grade EEQ in 2023 increased by 28% and 23.78%, respectively. Additionally, in the second phase (2011–2023), the average RSEI time series value significantly increased compared to the first phase (1990–2010). Among the climatic factors, annual precipitation had the greatest impact on EEQ, with an average contribution rate of 0.085. The conversion of unused land to forestland significantly improved the EEQ, with the area showing a very significant increase in RSEI, accounting for 82.30%. The areas in the mining region showing very significant, significant, and slight increases in RSEI were smaller than the overall study area. In conclusion, the overall EEQ in the study area has shown an improving trend, with climate change being the dominant factor in 71.52% of the areas where RSEI increased, while human activities were the dominant factor in 26.89% of the areas where RSEI decreased.

Considering the characteristics of extremely thick inclined open-pit coal mine with large amount under end slope, large end-slope height, and long exposure time, it is important to study the slope stability research during open-pit mining. This study takes the whole process of excavation descending and steep end-slope mining of an extremely thick inclined open-pit mine as the background. The slope stability factor of the end slopes were calculated for each stage of mining with different coal seam thicknesses by using the strength reduction method. The slope data, such as vertical stress, horizontal stress, and increment of maximum shear strain, are analyzed. The results show that the vertical stress and stability factor are decreasing throughout the mining stage. The horizontal stress shows a pattern of increasing and then decreasing in the excavation descending and steep end-slope mining. The greater the thickness of coal seam, the less the stability of the slope.

Damage deterioration of rocks in cold regions under seasonal changes and daily cycles of freezing and thawing generate a series of engineering geological problems. These problems will seriously affect the safe and efficient production of open-pit mines. In this paper, a freeze–thaw cycle test and uniaxial compression test considering the natural conditions of the slope were carried out. Mechanical properties and damage mechanisms of open-pit mine mudstone under freeze–thaw conditions were investigated based on nuclear magnetic resonance (NMR) technology. The test results show that the microscopic internal pore structure of mudstone was changed under the superimposed effect of freeze–thaw damage and hydration damage. The internal pore size of mudstone increased with the number of freeze–thaw cycles, while the average pore size of the natural mudstone test increased more. Macroscopically, the compressive strength and modulus of elasticity of mudstone varied linearly with the number of freezing cycles, and the compressive strength and modulus of elasticity showed a decreasing trend. The strain-softening characteristics of mudstone samples were significant for more freeze–thaw cycles. The study explains the microscopic causes of mudstone deterioration in open-pit mines in cold regions and offers guidance for solving engineering disasters caused by mudstone deterioration.