Forestry Industry Integration and Forest Ecological Security: Spatial Effects, Heterogeneity, and Transmission Mechanisms in China

Enhancing forest ecological security is essential for achieving carbon neutrality, while the ecological consequences of forestry industry integration provide an important lens through which to understand evolving human–land interactions. Examining the spatio-temporal dynamics of forest ecological security (FES) and identifying the pathways through which forestry industry integration (FII) affects FES are therefore important for maintaining ecological balance and promoting regional sustainability. Using provincial panel data for China from 2005 to 2021, we applied the Herfindahl–Hirschman Index, a comprehensive evaluation framework, a spatial Durbin model, and mediation analysis to assess FES and examine the mechanisms and spatial heterogeneity of the effects of FII on FES. The results show that FES improved overall during the study period, although marked differences persisted among the Southwest, Northeast, Southern, and Northern Forest regions. Provinces with favorable forest resource endowments, including Yunnan, Fujian, and Jilin, exhibited relatively high levels of FES, whereas Jiangsu, Shandong, Ningxia, and Xinjiang recorded comparatively low levels. FII had a significant positive effect on FES, and this effect became stronger at higher quantiles of forest ecological security. Moreover, FII generated positive spatial spillovers, benefiting not only the focal province, but also neighboring regions, with the indirect effect exceeding the direct effect. Mechanism analysis further showed that FII enhanced FES by improving forest resource endowments, alleviating pressure on forest resources, and promoting forestry economic development. These findings suggest that forest ecological security can be strengthened by leveraging agglomeration effects in high-FES regions, enhancing interregional cooperation, promoting coordinated development with neighboring areas, and further advancing forestry industry integration.