京津唐地区城市化对植被物候的影响研究

城市化过程使得土地利用、地表植被覆盖发生着显著的变化,如何定量化描述城市化对植被物候的影响越来越受到各方的关注。基于京津唐地区2001~2006年NDVI时间序列影像,得出了京津唐地区植被物候空间分布格局,计算出北京、天津、唐山3个核心城市城区的距离变量与平均植被物候,并分析了城市化对植被物候指标的影响趋势。结果表明:①2001~2006年,北京城市化使得城区及离城区较近的地方植被生长开始时间提前、结束时间推后、生长季周期变长、NDVI振幅减小;②天津和唐山的城市化使得城区及离城区较近的地方植被生长开始时间延后、结束时间提前、生长季周期变短,NDVI振幅减小;③城市化对植被物候的影响与该地区城市扩张类型存在相关性关系。

Impact of Urbanization on Vegetation Phenology Research in Beijing-Tianjin-Tangshan Region

The processing of urbanization makes land use and vegetation coverage change significantly.The impact of urbanization on vegetation phenology quantitatively causes more and more attention.Based on NDVI time series images from 2001 to 2006 of Beijing-Tianjin-Tangshan region,this paper got the spatial distribution pattern of the vegetation phenology and calculated the metric of vegetation phenology in urban areas and buffer zones of Beijing,Tianjin and Tangshan.Then this study analyzed the trend of urbanization impacts on vegetation phenology metrics.The results showed that from 2001 to 2006,the urbanization of Beijing caused the vegetation in the urban area where had an earlier start of growing season(SOS),later end of growing season(EOS),longer Growing Season Length(GSL) and smaller NDVI amplitude.But the urbanization of Tianjin and Tangshan made the vegetation in the urban area later SOS,earlier EOS,shorter GSL and smaller NDVI amplitude.The result also revealed there is a correlation relationship between the impact of urbanization on vegetation phenology and the type of city expansion.