联合国报告显示——全球城市人口增量将主要来自亚非国家

Core Insights - The report by the United Nations Department of Economic and Social Affairs predicts that by 2050, two-thirds of the global population growth will occur in urban areas, primarily in Asia and Africa [1][2] - It highlights a systematic relationship between urbanization levels and national income, indicating that higher urban population ratios correlate with increased economic productivity and income levels [2][3] Urbanization Trends - The proportion of the global population living in urban areas increased from 20% in 1950 to an expected 45% in 2025, with the number of megacities (over 10 million inhabitants) rising from 8 in 1975 to 33 in 2025, over half of which will be in Asia [1][2] - The report identifies that over half of the urban population growth from 2025 to 2050 will come from seven countries: India, Nigeria, Pakistan, the Democratic Republic of the Congo, Egypt, Bangladesh, and Ethiopia [1] Economic and Social Implications - Urbanization is seen as a fundamental driver of economic development, enhancing labor market activity and providing better access to healthcare, education, and employment opportunities [2][3] - However, rapid urban population growth can lead to significant urban pressures, including housing shortages, traffic congestion, and strained public services [3] Challenges of Urban Expansion - The report warns that unplanned urban expansion has outpaced population growth, leading to increased infrastructure costs, longer commuting times, and the encroachment on agricultural land, threatening food security and ecosystems [3] - Approximately 1 billion people live in informal settlements lacking basic services such as clean water and sanitation [3] Policy Recommendations - The report advocates for comprehensive urbanization strategies at national and city levels, emphasizing the need for coordinated governance to manage urban growth sustainably [4][5] - It suggests prioritizing compact city development to reduce land consumption and emissions while protecting ecosystems, and integrating urban and rural governance to enhance connectivity and reduce disparities [4][5] Addressing Future Challenges - To tackle issues related to population growth, aging, and informal settlements, the report recommends improving housing, transportation, and sanitation facilities in rapidly urbanizing areas [5] - It also calls for the development of "age-friendly cities" and climate-resilient infrastructure to better prepare for climate risks [5]