ObjectiveThe objectives of this paper is to study the relationship between forest structure and forest productivity and its driving mechanism, so as to improve the forest structure, optimize forest ecosystem function, and improve forest productivity.

MethodThen temperate forests in the Northeastern was taken as the research object and a network of 327 survey plots was established on the seven main mountain ranges distributed in temperate forests, with a total area of 32.7 hm². Based on the field survey data of 26 348 trees, the structural equation model (SEM) was used to study the path and strength of forest productivity based on species diversity and structure diversity under large-scale conditions. Besides, the relationship between climatic factors and forest productivity and their driving mechanism were also analyzed.

Results(1) Both species diversity and structure diversity showed significant positive correlations with forest productivity, and these two factors were strongly correlated. (2) Temperature and precipitation have no direct impact on productivity, but instead act on productivity by adjusting structure diversity and species diversity. (3) Similarly, dominant height of stand put impacts on productivity by adjusting forest structure and showed stronger influence than temperature and precipitation.

ConclusionStructure diversity and species diversity are direct driving factors for forest productivity in temperate forests in Northeast China, while climatic factors and dominant height of stand affect forest productivity by influencing forest structure. The results provide a theoretical basis for the sustainable management and management of temperate forests in Northeast China, showing important practical significance.