Catalyzing afforestation for enhanced organic matter generation in the vegetation ecosystems of the Yellow River economic zone: Insights derived from gross primary production.

Afforestation is a national policy in China, yet the impact of afforestation on the accumulation of organic matter within this ecosystem of the Yellow River Economic Zone (YREZ) remains somewhat elusive. This study, characterized by its comprehensiveness, included an array of data streams encompassing MODIS-derived gross primary productivity (GPP) data, meteorological insights, topographical particulars, land usage categorizations, population density metrics, and nocturnal luminosity records. The Theil-Sen median estimator, Mann–Kendall significance test, partial correlation coefficient analysis, and geodetector model were applied to assess the spatiotemporal characteristics of GPP and reveal the factors influencing the spatial heterogeneity of GPP within the YREZ and its provinces. The findings revealed a consistent ascending trajectory of GPP within the YREZ from 2000 to 2021. Shaanxi and Shanxi Provinces exhibited notably greater GPP increases, surpassing 80.00%, and outperformed Inner Mongolia and Henan. Spatial heterogeneity was chiefly driven by relative humidity and precipitation, except in Henan, where human factors had a greater influence. The land use category exerted a considerable impact on the spatial arrangement of GPP. The interplay between precipitation and land use type predominantly caused GPP heterogeneity in the economic sphere, while other factors played pivotal roles within the provinces. Precipitation and temperature had predominantly positive effects on GPP variation, with Inner Mongolia and Shanxi experiencing discernible positive effects fueled by precipitation. Overall, this study unravels the trajectory of GPP evolution, engendering an exhaustive understanding of the propelling forces engendering its variegated spatial disparities in the YREZ. • A substantial 97.49% of the YREZ witnessed an increase in GPP. • Human factors dominated the spatial heterogeneity of GPP in Henan. • The interaction between land use type and climate factors took precedence in the YREZ. • GPP in the YREZ exhibited positive correlations with precipitation and temperature. • Urbanization expansion, at the expense of farmland land and forest land, inhibited GPP growth. [ABSTRACT FROM AUTHOR]