中国北方农牧交错带城市扩展过程对植被净初级生产力影响研究--以呼包鄂地区为例

Impacts of urban expansion on net primary productivity in the agro-pastoral ecotone in Northern China:a case of Hohhot-Baotou-Ordos region

评价中国北方农牧交错带城市扩展过程对植被净初级生产力(Net Primary Productivity,NPP)的影响是揭示区域城市扩展过程生态效应的基础。以正在经历快速城市化的呼包鄂地区为例,基于空间分辨率为30 m的土地利用/覆盖数据,评价了该地区2000-2015年城市扩展过程对NPP的影响。研究结果表明,呼包鄂地区城市扩展导致NPP明显增加,2000-2015年城市扩展区域NPP均值从429.67 NDVI·PAR增加到489.71 NDVI·PAR,增加了13.97%。呼包鄂地区以城市土地占用草地为主要特征的城市扩展方式是城市扩展区域NPP增加的主要原因。

Assessing the impacts of urban expansion on the Net Primary Productivity （NPP） is essential for un- derstanding the ecological issues caused by urbanization in the drylands in northern China. In this study, we as- sessed the impacts of urban expansion on NPP in Hohhot-Baotou-Ordos （HBO） region a rapidly urbanizing area in the drylandsin northern China. Based on the land use/cover map with a resolution of 30 meters, we exam- ined the spatiotemporal patterns of NPP of urban land in HBO duringthe period of 2009-2013, and compared them with those derived from other land cover types. The results showthat the mean NPP of urban land was 572.50 NDVI. PAR, which was 3.81% higher than the regional average. The largest NPP value of urban land, oc- curring in July, was 123.94 NDVI-PAR, which was 7.33% higher than the regional average. The urban expansion dominated by the conversion from grassland to urban land would increase regional NPP in HBO.