Unveiling scale effects in human settlement environment suitability through a novel multi-factor weighting approach

Rural human settlement environment suitability is a key indicator for guiding land-use planning and promoting sustainable rural revitalization. This study develops a refined framework for evaluating the natural suitability of rural human settlement environments in central Hunan, China, using GIS-based spatial analysis. We propose an enhanced factor-weighting method that integrates normalized information entropy (NIE) and the coefficient of variation (CV) into a Pearson correlation coefficient (PCC)-driven approach, thereby improving the objectivity and sensitivity of weight determination. Comparative experiments demonstrate that this hybrid method captures the relative influence of natural factors more accurately than traditional PCC-based techniques. Results reveal a pronounced scale effect: as the spatial analysis scale decreases, disparities in factor weights become more evident. The spatial distribution of suitability exhibits a distinct east-high, west-low gradient, reflecting strong spatial heterogeneity across the region. Among all factors, terrain relief emerges as the dominant driver of suitability variations. Based on the calculated suitability index, the study delineates five functional zones and formulates corresponding development strategies tailored to local conditions. These findings offer a scientific basis for optimizing rural spatial planning and promoting sustainable development in central Hunan and similar regions. Beyond the case region, the framework provides a transferable approach for evaluating natural suitability in other mountainous rural areas. It also offers practical guidance for policymakers seeking to balance ecological protection with sustainable land-use development.