城市化过程中北京市人口时空演变对生态系统质量的影响

Impacts of population spatio-temporal dynamics on ecosystem quality during fast urbanization in Beijing,China

应用第五、第六次人口普查和MODIS-NDVI遥感数据,从城市、区/县和街道/乡镇3个尺度,分析了2000—2010年北京市人口时空演变特征及其对区域生态系统质量的影响.结果表明：研究期间,北京市总人口增长了43.9%,人口空间分布形成了明显的圈层特征,呈现向近郊转移聚集的趋势;北京市的年最大归一化植被指数（NDVI）呈增加趋势,在5~6环之间却显著降低.城区和远郊区的NDVI变化趋势与人口密度变化率呈显著负相关.城市化带来的人口数量增加不仅没有导致北京整体生态系统质量下降,反而通过城市功能调整和农民进城务工人口转移等方式,提高了城区和远郊区的生态系统质量.不同的功能定位和发展机制是影响北京市人口时空格局变化及其生态影响的主要原因.

The spatio-temporal dynamics of population and its impact on the regional ecosystem quality in Beijing were analyzed at city-county-township hierarchical levels dtaring 2000 to 2010, based on the 5th and 6th population census data and MODIS-NDVI thematic dat~ We found that the resident population of Beijing increased by 43.9% during the study period, and the trend of popula- tion gathering to the urban fringe resulted in an obviously circular distribution. The annual maximum NDVI of Beijing had the trend of increase, however, decreased significantly between the 5th Ring and the 6th Ring. The change trends of NDVI in urban and exurban areas showed significantly nega- tive relationships with the change ratios of population density, respectively. The increment of urban population caused by urbanization did not show negative influence on the regional ecosystem quality of Beijing. On the contrary, the ecosystem quality in urban core and exurban areas was improved, due to the adjustment of city functions and the population transfer from rural to urban area. There- fore, the functional orientation and development mechanism were the main contribution to the evolu- tion of population pattern and its ecological impacts.