基于半变异函数的环渤海地区NDVI空间格局特征研究

Analysis of spatial patterns of NDVI over the Circum-Bohai Sea region based on semi-variogram

基于环渤海地区1999—2009期间年尺度的NDVI序列数据和半变异函数分析方法,定量研究植被覆盖分布的空间格局特征及其时间变化特征,结论如下:1)辽宁省地形对植被分布的影响强于气候,植被分布整体的连续性最好;而在山东和京津冀区域,温度对植被覆盖空间格局的影响强于水分,且山东植被分布的斑块化最为显著;2)结构性因子对辽宁、京津冀、山东三个分区植被覆盖的影响作用占主导,但均呈减弱趋势;3)辽宁、京津冀、山东三个分区植被覆盖空间变异最小、空间连续性最大的方向分别为东北-西南(30°)、西北-东南(150°)和西北-东南(135°),该方向的差异体现了影响因子类型及其作用的差异性。

The spatial-temporal characteristics of vegetation cover in the Circum-Bohai Sea Region from 1999 to 2009 were studied based on annual NDVI data and semi-variogram. Main conclusions are as follows. 1） The vegetation cover of Liaoning exhibited the highest continuity, while the fragmentization of the vegetation cover in Shandong Province was outstanding; impacts of terrain on the spatial distribution of vegetation cover were stronger than those of climate factors in Liaoning Province, while in Shandong Province and the Beijing-Tianjin-Hebei region, impacts of temperature were stronger than those of moisture; 2） Structural factors are dominating factors that impact on spatial patterns of vegetation cover in Liaoning Province, Shandong Province and Beijing-Tianjin-Hebei region, however, their impacts showed a weakening trend; 3） Directions in which the spatial patterns of vegetation cover were most continuous in Liaoning province, Shandong province and Beijing-Tianjin-Hebei region were northeast-southwest （30°）, northwest-southeast （150°） and northwest-southeast （135°）, respectively, indicating the variability of impact factors＇ distribution and their roles in influencing the spatial patterns of vegetation cover.