The implementation of China’s ex situ poverty alleviation and relocation project has alleviated the further deterioration of the ecological environment in the relocation area. It can create favorable conditions for the management of ecological problems such as the natural restoration of rocky desertification and soil erosion. Panzhou City, Guizhou Province, is one of the key areas for the implementation of ex situ poverty alleviation and relocation projects in the 13th Five-Year Plan for China’s National Economic and Social Development. The typical ecological problem of karst rocky desertification is an important factor hindering the sustainable development of local society, economy, and ecology. Based on the five-phase remote sensing images and relocated population data, the dynamic change rate, transition matrix, and coupling coordination degree model are utilized to analyze the spatiotemporal changes in rocky desertification in Panzhou City. Meanwhile, the cellular automata (CA) Markov model is used to simulate its future scenarios of rocky desertification. The results show that (i) over the past 20 years, the vegetation coverage in Panzhou has generally increased. The implementation of the ex situ poverty alleviation and relocation project has significantly promoted the reduction of the area and degree of rocky desertification. After relocation (2015–2020), the positive improvement rate of rocky desertification accelerated. (ii) After relocation, the potential rocky desertification (PRD), light rocky desertification (LRD), medium rocky desertification (MRD), severe rocky desertification (SRD), and extreme severe rocky desertification (ESRD) showed a trend of transition to the no rocky desertification (NRD). The improvement effect of rocky desertification is remarkable, and the main contribution is from the PRD and LRD. (iii) The greater the relocation intensity is, the more obvious the improvement effect of the rocky desertification area is, and the higher the corresponding coupling coordination level is. The coupling coordination between LRD and relocation intensity is the highest. (iiii) The forecast results show that by 2025 and 2035, rocky desertification in Panzhou will continue to improve.

Vegetation restoration in ecologically fragile areas has a significant carbon sequestration (CS) effect. However, it is usually difficult to achieve quantitative assessment at the regional scale for this part of human activity intervention. The Chinese government's ex‐situ poverty alleviation and relocation (EPAR) project has relocated approximately 10 million people from areas with a fragile ecological environment to urban centralized resettlement, which is a typical case of weakened environmental intervention by human activities (Guizhou Province accounting for approximately 20% of the total relocated population in China). The CS model of vegetation photosynthesis and spatial analysis of geographic information were used to quantify the contribution of human activities to the natural restoration of vegetation CS, based on the data of net primary productivity (NPP) of vegetation from 2000 to 2020. The results show that the implementation of the EPAR project acts as an external force to drive vegetation restoration and CS, which increases the slope of the carbon density change trend (from k = 30.9 to k = 57.41), resulting in an overall carbon density increase of 26.51 tCkm−2. The regional spatial analysis showed that the correlation coefficients between carbon density and relocation intensity in the 5‐year and 10‐year change were r = 0.976 (p < 0.01) and r = 0.949 (p < 0.05), respectively, indicating a significant positive correlation. Based on this, the CS contribution of vegetation in 84 districts in Guizhou Province that implemented EPAR projects was calculated, showing that 79 districts contributed positively, accounting for 94%. The average contribution of CS by vegetation restoration in each district was 0.0556 Tg, and offset CO2 emissions were 0.2059 Tg. The other five districts with a negative contribution to CS were distributed in regions with relatively stable ecosystems and mature forests. This shows that human intervention in the environment changes more significantly in fragile ecological areas.

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