Changes in the functional use of urban land have become an important challenge affecting urban structure and sustainable development. An-Najaf City, Iraq, has experienced substantial functional transformation over the past two decades, including residential expansion, commercial growth, industrial development, and the emergence of informal settlements. This study analyzes functional land-use changes in An-Najaf City and predicts future transformation using a Markov chain model. Land-use data for 2005, 2015, and 2025 were obtained from official records, geographic information system (GIS)-based land-use maps, recent satellite imagery, and field verification. Transition probability matrices were constructed for the 2005–2015 and 2015–2025 periods, and the 2015–2025 matrix was used to predict the functional land-use distribution for 2035. The results show that residential and commercial land uses increased substantially from 2005 to 2025, with commercial land recording the largest increase, from 200.30 ha to 2,204.30 ha. Informal settlements were also identified as an important factor affecting urban functional change. Based on the Markov prediction, residential land is projected to increase to approximately 5,204.7 ha by 2035, slum areas to 482.3 ha, and industrial land to 876.4 ha. By contrast, commercial land is projected to decline to approximately 1,816.1 ha, while the “Others” category is expected to decrease to 204.5 ha. Since the prediction is applied within the defined 2025 study boundary, the total land area remains constant, and the results represent internal functional transformation rather than further physical urban expansion. The findings highlight the need for planning policies that control informal settlement growth, manage residential and industrial expansion, protect supporting urban functions, and promote balanced urban development in An-Najaf City.

Advancing the digital economy and improving eco-efficiency in a coordinated manner are important for high-quality and sustainable regional development. However, the spatio-temporal patterns of their coupling relationship and the factors associated with coordinated development remain insufficiently understood, particularly within the Yangtze River Economic Belt (YREB). To address this gap, the levels of digital economy development and eco-efficiency in 108 YREB cities were evaluated for the period 2011–2022 by integrating the entropy weight method (EWM) and the super epsilon-based measure (Super-EBM) model. The coupling coordination degree (CCD) model was subsequently employed to quantify the degree of coordinated development between the two systems, while the extreme gradient boosting (XGBoost) machine learning algorithm was applied to identify and interpret the major factors associated with the CCD. The results indicate that the digital economy development level exhibited an overall upward, albeit fluctuating, trajectory and was characterized by a distinct spatial gradient of “downstream > midstream > upstream.” In contrast, eco-efficiency remained relatively stable with moderate fluctuations and displayed the opposite spatial distribution. The CCD between the digital economy and eco-efficiency increased steadily throughout the study period. Pronounced spatial heterogeneity was observed, with consistently higher CCD values in downstream cities than in midstream and upstream areas. Improvements in the upstream and midstream regions occurred at a comparatively slower pace, which may be related to disparities in development conditions and resource endowments. Feature importance analysis based on the XGBoost model further showed that openness to the outside world, technological innovation, and urbanization generally made positive contributions to the predicted CCD, whereas government intervention and industrial structure generally made negative contributions. These findings offer new insights into the coordinated evolution of digitalization and ecological sustainability and suggest that better-targeted policy support, strengthened interregional collaboration, enhanced digital infrastructure, innovation-driven development, and deeper integration of digital technologies with green transformation should be promoted to achieve balanced and sustainable development across the YREB.