Effects on the Close-to-nature Management on Structure and Distribution Pattern of Pinus massoniana Population

This study takes Pinus massoniana forest after close-to-nature management for more than 10 years as the research object, through the investigation of typical sample plots and based on the method of population statistics to explore the effects of close-to-nature management on the population structure and distribution pattern of Pinus massoniana. The results show that: In the control and management of Pinus massoniana population in the study area, the number of young individuals(age class Ⅰ and Ⅱ) is very small, the age class distribution is unreasonable, and the population structure is unstable. Although close-to-nature management can increase the total number of young individuals, the effect is still not ideal. The individual quantity advantage of Pinus massoniana population may be weakened, and the population shows a declining trend. After the development of 6 age classes, the structure of the population gradually showed a steady growth trend. The population of Pinus massoniana showed the characteristics of aggregate distribution, and the aggregation degree of Pinus massoniana population in the control stand was significantly higher than that in the managed stand. With the increase of age class, the population distribution pattern shows the trend of aggregation-uniform-random distribution, and close-to-nature management can accelerate the succession process of population distribution pattern to a more stable random distribution. In summary, the main reason for the unreasonable population structure of Pinus massoniana in the study area is the insufficient number of young individuals. close-to-nature management can improve the population structure and distribution pattern to some extent. Therefore, it is suggested that on the basis of close-to-nature management, combined with artificial promotion of natural renewal, to increase the number of young individuals and speed up the realization of stable and sustainable development of the population.