Insights into spatiotemporal dynamics and driving mechanisms of vegetation net primary productivity in African terrestrial ecosystems

作者：Liang Liang, Meng Li, Ziru Huang, Qianjie Wang, Zhen Yang, Shuguo Wang · 发表于：International Journal of Applied Earth Observation and Geoinformation · 年份：2025 · DOI：10.1016/j.jag.2025.104824 · 被引用次数：2 · 研究领域：Ecology and Vegetation Dynamics Studies、Land Use and Ecosystem Services、African Botany and Ecology Studies

• The annual variation of NPP in Africa shows an upward trend despite fluctuations. • NPP in Africa exhibits a primary 20-year cycle with two oscillations during 1981–2018. • NPP in Africa demonstrates spatial heterogeneity and anti-persistence. • African NPP is primarily driven by natural factors like rainfall & extreme temperatures. Net Primary Productivity (NPP) is a critical measure of ecosystem vitality. This paper examines the spatiotemporal variation in NPP across Africa during 1981–2018 using Theil-Sen slope estimation and wavelet analysis. Sustainable change characteristics in different regions are analyzed using the Hurst exponent, and the influence of driving factors on African NPP are quantified through a structural equation model (SEM). The analysis revealed that: (1) The annual variation curve of African NPP demonstrated a fluctuating upward trajectory (p = 0.001) throughout the study period. Wavelet analysis revealed a cyclical pattern with a primary period of about 20 years, characterized by two upward and downward transitions during 1981–2018. (2) Spatial analysis indicates the distribution of NPP across Africa is centered around the equator and gradually decreases towards higher latitudes, in which the NPP of tropical rainforest and its adjacent areas increases significantly, covering 40.2 % of Africa’s area. However, Hurst exponent analysis reveals that NPP in Africa generally exhibits anti-sustainability changes, with 52.8 % of the total area potentially s...