Spatiotemporal patterns and structural pathways of area-efficiency dynamics in global urban and rural settlements

Global urban and rural settlement expansion has reshaped ecological systems in recent decades. Urban land extent has tripled, while rural settlements have continued to expand despite declining rural populations. However, limited high-resolution rural settlement data and oversimplified analytical metrics constrain understanding of these dynamics. Here, we used 100 m-resolution Global Urban and Rural Settlements (GURS) and GHS-POP datasets to assess changes in settlement area and efficiency across multiple spatial scales from 2000 to 2020. We also used structural equation modeling (SEM) to estimate direct and indirect socioeconomic effects within a theory-guided framework. Globally, rural settlements consistently occupied at least 1.29 times as much land as urban settlements, although urban settlements expanded faster (2.53% versus 1.56% annually). Efficiency loss was associated with estimated additional expansion of 30.98% for rural settlements and 8.14% for urban settlements. Asia, particularly China and India, had the largest settlement areas and the highest expansion rates. Efficiency declines were pronounced in Asia and Europe, reaching 20% for urban settlements and 30% for rural settlements. Socioeconomic effects differed between urban and rural settlements, but the SEM indicated a consistent pattern: demographic effects were predominantly direct, whereas economic factors often had larger indirect effects. Urban and rural settlement outcomes were positively associated, while area and efficiency were negatively associated within each settlement type. These findings support coordinated governance across spatial scales, with strategies to improve settlement efficiency tailored to regional settlement patterns and demographic conditions.