The spatiotemporal evolution of net primary productivity, and its
influencing factors in the Yellow River Basin
Abstract
Ecosystem vulnerability in the Yellow River Basin (YRB) is a prominent
concern. An in-depth exploration of net primary productivity (NPP)
serves as an important aspect of assessing and protecting ecosystem
health. We explored spatiotemporal changes and influencing factors of
NPP in the YRB from 2000–2015, using a range of spatial analysis
techniques, and cutting-edge computing-intensive variable importance
decomposition methods. We found that NPP showed a fluctuating growth
trend over time, ranging from 181.0–259.1 gC∙m -2∙a
-1, as well as a clear negative south-north spatial
gradient. Significant spatial clustering patterns were observed, with
Low-Low and High-High clusters being the dominant area classifications
at grid cell, county, and city scales in the study area. We also found
that NPP was statistically significantly affected by both natural
factors (including climate and topography), and human activities, whilst
meteorological factors were the most important factor and explained, on
average, roughly 66% of the variability in NPP. Although the impact of
human activities on NPP was relatively low when compared to natural
factors, the former tended to increase with time and accounted for
roughly 30% of the total variability explained by the model in 2015.
Overall, this study provides an improved technical framework for
undertaking a comprehensive analysis of the spatiotemporal pattern of
NPP and its influencing factors at multiple-spatial scales.