京津冀地区植被净初级生产力时空分布及其与地形因子的关系

Spatiotemporal Distribution of Vegetation Net Primary Productivity and Its Relationship with Topographic Factors in Beijing-tianjin-hebei Region

基于2000-2014年中分辨率成像光谱仪MODIS的MOD17A3数据,分析了京津冀地区植被净初级生产力(net primary productivity,NPP)的时空分布,探讨高程和坡度因子对植被NPP的影响。结果表明,京津冀地区2000-2014年年均NPP主要集中在200~300 gC/(m^2·a)。2000-2014年植被NPP波动变化,并呈增长趋向。15年间植被NPP均值2004年最高,高达356 gC/(m^2·a),其次是2008年,为313 gC/(m^2·a),最低是2001年,为223 gC/(m^2·a)。京津冀北部地区年均NPP与经向地带分异规律一致,由东向西递减;京津冀西部地区年均NPP与纬向地带分异规律一致,由南至北递减。京津冀中部地区太行山东部存在一个高值区。高程和坡度是植被NPP变化重要因子,并且随着高程和坡度升高,植被NPP降低。

Based on MOD17 A3 data of MODIS(moderate-resolution imaging spectroradiometer) from 2000 to 2014, the spatiotemproal distribution and changes of vegetation net primary productivity of Beijing-Tianjin-Hebei region were analyzed, and the effects of two basic topographic factors including elevation and slope on vegetation net primary productivity(NPP) were explored. The results showed that the annual NPP values of Beijing-Tianjin-Hebei region were mainly concentrated at 200~300 gC/(m^2·a). From 2000 to 2014, the NPP of Beijing-Tianjin-Hebei region showed an increasing trend with fluctuating change. The NPP value of vegetation was the highest in 2004, up to 356 gC/(m^2·a). The second was 313 gC/(m^2·a) in 2008. The lowest was 223 gC/(m^2·a) in 2001.The NPP of Beijing-Tianjin-Hebei region was consistent with zonality differentiation. The trend of annual NPP decreasing from east to west in the northern part was in accordance with longitude zonality differentiation. The annual average NPP in the western part decreased from south to north, which was consistent with latitude zonality differentiation. High NPP values appeared in the east of Taihang Mountain in central Beijing-Tianjin-Hebei region. Elevation and slope were important factors influencing vegetation NPP, and the higher elevation and slope were, the lower vegetation NPP values were.