Abstract:

Based on MOD17A3 product data for Shandong Province from 2010 to 2022, this study uses univariate regression trend analysis, the coefficient of variation method, partial correlation analysis, and the Hurst index method to investigate the spatiotemporal distribution of vegetation net primary productivity (NPP) for the ecosystem of Shandong Province and analyze the impact of climate factors. Results demonstrate the fluctuating upward trend of vegetation NPP for Shandong Province in recent years, with an annual average of (398.03±150.20) g/(m²·a), higher than the national average and comparable with that of the Beijing-Tianjin-Hebei region. Vegetation NPP varies considerably across different areas. The vegetation NPP in the eastern coastal hilly area is higher than that in the inland plain area. With respect to interannual variation, the overall vegetation NPP in Shandong Province is relatively stable. With regard to the variation trend of vegetation NPP, the areas of positive and negative trends are equivalent. The trend analysis shows that 27.86% of the areas show an increasing trend, whereas 33.49% show a decreasing trend. However, the areas that have shifted from the increasing trend to the decreasing trend are mostly in woodland areas with high vegetation NPP levels, and further research is needed. In general, a positive correlation exists between vegetation NPP and climate factors. Temperature has a wider and more considerable impact on vegetation NPP than precipitation; moreover, the correlation between vegetation NPP and climate factors is poor in plain agricultural areas.

Key words: net primary productivity of vegetation, spatiotemporal variation, climate factors, Shandong Province