Effects of different management models on leaf functional traits and soil physical and chemical properties of natural secondary forest of Quercus mongolica

Abstract

Plant functional traits is a bridge between plants and the environment, and can reflect the mechanisms of plant adaptation to the external environment. The natural secondary forest of Quercus mongolica under three management models in the Danqinghe forest farm in Harbin, Heilongjiang province, was used as the research object, to study the leaf functional traits and the relationship between leaf functional traits and soil physical and chemical properties, which is of great significance in understanding plants' adaptation to the environment and the formation of plant communities. The results showed that: (1) there were no significant differences in the soil physical and chemical properties, and in total soil potassium, available potassium, and organic carbon content, between the different management models of the natural secondary Quercus mongolica forest; (2) the functional traits of the natural secondary Quercus mongolica forest under different management models were obviously different; the individual leaf area in the target tree management model was significantly higher than that in the ecosystem management model and the no-interference model(P <0.01); the leaf area was sidnificantly negatively related with the leaf nitrogen and organic carbon content (P<0.01); and there was significant positive correlation between the leaf nitrogen content and leaf organic carbon content (P<0.01); (3) soil organic carbon had significant influence on the individual leaf area, leaf nitrogen content, leaf phosphorus content, and leaf organic carbon content. Therefore, the ability to self-recover in the natural secondary Quercus mongolica forest under different management models was stronger, and soil nutrients in woodland was not lost by different degrees of tending. Soil organic carbon was the main factor affecting the variation of leaf functional traits in the natural secondary Quercus mongolica forest under different management models. The natural secondary Quercus mongolica forest communities adapt to the environment through the coupling or combination of functional traits. The response of plant functional traits on soil physicochemical properties is an elaborate process; we need to strengthen their long-term monitoring and conduct more research.